# Copyright (c) 2025 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import math
import warnings
from dataclasses import dataclass
from typing import Any, Callable, Dict, List, Optional, Tuple, Union

import numpy as np
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.nn import CrossEntropyLoss
from torch.nn.init import _calculate_fan_in_and_fan_out
from transformers.activations import ACT2FN, GELUActivation
from transformers.cache_utils import (
    Cache,
    DynamicCache,
)
from transformers.masking_utils import create_causal_mask
from transformers.generation import GenerationMixin
from transformers.integrations import use_kernel_forward_from_hub
from transformers.modeling_attn_mask_utils import AttentionMaskConverter
from transformers.modeling_layers import GradientCheckpointingLayer
from transformers.modeling_outputs import (
    BaseModelOutput,
    BaseModelOutputWithPast,
    BaseModelOutputWithPooling,
    CausalLMOutputWithPast,
)
from transformers.modeling_rope_utils import ROPE_INIT_FUNCTIONS, dynamic_rope_update
from transformers.modeling_utils import (
    ALL_ATTENTION_FUNCTIONS,
    PreTrainedModel,
    sdpa_attention_forward,
)
from transformers.processing_utils import Unpack
from transformers.utils import (
    ModelOutput,
    TransformersKwargs,
    auto_docstring,
    can_return_tuple,
    is_flash_attn_2_available,
    torch_int,
)
from transformers.utils.generic import check_model_inputs

if is_flash_attn_2_available():
    from flash_attn import flash_attn_varlen_func
    from flash_attn.layers.rotary import apply_rotary_emb
else:
    flash_attn_varlen_func = None
    apply_rotary_emb = None

from .configuration_paddleocr_vl import PaddleOCRVisionConfig, PaddleOCRVLConfig


class RotaryEmbedding(nn.Module):
    def __init__(self, config: PaddleOCRVLConfig, device=None):
        super().__init__()
        self.rope_kwargs = {}

        # BC: "rope_type" was originally "type"
        if config.rope_scaling is not None:
            self.rope_type = config.rope_scaling.get(
                "rope_type", config.rope_scaling.get("type")
            )
        else:
            self.rope_type = "default"
        self.max_seq_len_cached = config.max_position_embeddings
        self.original_max_seq_len = config.max_position_embeddings

        # BC: "rope_type" was originally "type"
        if hasattr(config, "rope_scaling") and config.rope_scaling is not None:
            self.rope_type = config.rope_scaling.get(
                "rope_type", config.rope_scaling.get("type")
            )
        else:
            self.rope_type = "default"
        self.max_seq_len_cached = config.max_position_embeddings
        self.original_max_seq_len = config.max_position_embeddings

        self.config = config
        self.rope_init_fn = ROPE_INIT_FUNCTIONS[self.rope_type]

        inv_freq, self.attention_scaling = self.rope_init_fn(self.config, device)
        self.register_buffer("inv_freq", inv_freq, persistent=False)
        self.original_inv_freq = self.inv_freq

    def _dynamic_frequency_update(self, position_ids, device):
        """
        dynamic RoPE layers should recompute `inv_freq` in the following situations:
        1 - growing beyond the cached sequence length (allow scaling)
        2 - the current sequence length is in the original scale (avoid losing precision with small sequences)
        """
        seq_len = torch.max(position_ids) + 1
        if seq_len > self.max_seq_len_cached:
            inv_freq, self.attention_scaling = self.rope_init_fn(
                self.config, device, seq_len=seq_len, **self.rope_kwargs
            )
            self.register_buffer("inv_freq", inv_freq, persistent=False)
            self.max_seq_len_cached = seq_len

        if (
            seq_len < self.original_max_seq_len
            and self.max_seq_len_cached > self.original_max_seq_len
        ):
            self.register_buffer("inv_freq", self.original_inv_freq, persistent=False)
            self.max_seq_len_cached = self.original_max_seq_len

    @torch.no_grad()
    def forward(self, x, position_ids):
        if "dynamic" in self.rope_type:
            self._dynamic_frequency_update(position_ids, device=x.device)

        inv_freq_expanded = (
            self.inv_freq[None, None, :, None]
            .float()
            .expand(3, position_ids.shape[1], -1, 1)
        )
        position_ids_expanded = position_ids[
            :, :, None, :
        ].float()  # shape (3, bs, 1, positions)
        # Force float32 (see https://github.com/huggingface/transformers/pull/29285)
        device_type = x.device.type
        device_type = (
            device_type
            if isinstance(device_type, str) and device_type != "mps"
            else "cpu"
        )
        with torch.autocast(device_type=device_type, enabled=False):
            freqs = (
                inv_freq_expanded.float() @ position_ids_expanded.float()
            ).transpose(2, 3)
            emb = torch.cat((freqs, freqs), dim=-1)
            cos = emb.cos()
            sin = emb.sin()

        # Advanced RoPE types (e.g. yarn) apply a post-processing scaling factor, equivalent to scaling attention
        cos = cos * self.attention_scaling
        sin = sin * self.attention_scaling

        return cos.to(dtype=x.dtype), sin.to(dtype=x.dtype)

    def rope_init(self):
        inv_freq, self.attention_scaling = self.rope_init_fn(
            self.config, device=None, **self.rope_kwargs
        )
        self.register_buffer("inv_freq", inv_freq, persistent=False)
        self.original_inv_freq = self.inv_freq


class Ernie4_5RotaryEmbedding(nn.Module):
    def __init__(self, config: PaddleOCRVLConfig, device=None):
        super().__init__()
        # BC: "rope_type" was originally "type"
        if hasattr(config, "rope_scaling") and isinstance(config.rope_scaling, dict):
            self.rope_type = config.rope_scaling.get(
                "rope_type", config.rope_scaling.get("type")
            )
        else:
            self.rope_type = "default"
        self.max_seq_len_cached = config.max_position_embeddings
        self.original_max_seq_len = config.max_position_embeddings

        self.config = config
        self.rope_init_fn = ROPE_INIT_FUNCTIONS[self.rope_type]

        inv_freq, self.attention_scaling = self.rope_init_fn(self.config, device)
        self.register_buffer("inv_freq", inv_freq, persistent=False)
        self.original_inv_freq = self.inv_freq

    @torch.no_grad()
    @dynamic_rope_update  # power user: used with advanced RoPE types (e.g. dynamic rope)
    def forward(self, x, position_ids):
        inv_freq_expanded = (
            self.inv_freq[None, :, None]
            .float()
            .expand(position_ids.shape[0], -1, 1)
            .to(x.device)
        )
        position_ids_expanded = position_ids[:, None, :].float()
        device_type = (
            x.device.type
            if isinstance(x.device.type, str) and x.device.type != "mps"
            else "cpu"
        )
        with torch.autocast(device_type=device_type, enabled=False):  # Force float32
            freqs = (
                inv_freq_expanded.float() @ position_ids_expanded.float()
            ).transpose(1, 2)
            emb = torch.cat((freqs, freqs), dim=-1)
            cos = emb.cos() * self.attention_scaling
            sin = emb.sin() * self.attention_scaling

        # keeping it in full precision
        return cos, sin


class Ernie4_5MLP(nn.Module):
    def __init__(self, config: PaddleOCRVLConfig):
        super().__init__()
        self.config = config
        self.hidden_size = config.hidden_size
        self.intermediate_size = config.intermediate_size

        self.gate_proj = nn.Linear(
            self.hidden_size, self.intermediate_size, bias=config.use_bias
        )
        self.up_proj = nn.Linear(
            self.hidden_size, self.intermediate_size, bias=config.use_bias
        )
        self.down_proj = nn.Linear(
            self.intermediate_size, self.hidden_size, bias=config.use_bias
        )
        self.act_fn = ACT2FN[config.hidden_act]

    def forward(self, x):
        down_proj = self.down_proj(self.act_fn(self.gate_proj(x)) * self.up_proj(x))
        return down_proj


def repeat_kv(hidden_states: torch.Tensor, n_rep: int) -> torch.Tensor:
    """
    This is the equivalent of torch.repeat_interleave(x, dim=1, repeats=n_rep). The hidden states go from (batch,
    num_key_value_heads, seqlen, head_dim) to (batch, num_attention_heads, seqlen, head_dim)
    """
    batch, num_key_value_heads, slen, head_dim = hidden_states.shape
    if n_rep == 1:
        return hidden_states
    hidden_states = hidden_states[:, :, None, :, :].expand(
        batch, num_key_value_heads, n_rep, slen, head_dim
    )
    return hidden_states.reshape(batch, num_key_value_heads * n_rep, slen, head_dim)


def eager_attention_forward_ernie(
    module: nn.Module,
    query: torch.Tensor,
    key: torch.Tensor,
    value: torch.Tensor,
    attention_mask: Optional[torch.Tensor],
    scaling: float,
    dropout: float = 0.0,
    **kwargs: Unpack[TransformersKwargs],
):
    key_states = repeat_kv(key, module.num_key_value_groups)
    value_states = repeat_kv(value, module.num_key_value_groups)

    attn_weights = torch.matmul(query, key_states.transpose(2, 3)) * scaling
    if attention_mask is not None:
        causal_mask = attention_mask[:, :, :, : key_states.shape[-2]]
        attn_weights = attn_weights + causal_mask

    attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(
        query.dtype
    )
    attn_weights = nn.functional.dropout(
        attn_weights, p=dropout, training=module.training
    )
    attn_output = torch.matmul(attn_weights, value_states)
    attn_output = attn_output.transpose(1, 2).contiguous()

    return attn_output, attn_weights


def apply_rotary_pos_emb(q, k, cos, sin, position_ids=None, unsqueeze_dim=1):
    """Applies Rotary Position Embedding to the query and key tensors.

    Args:
        q (`torch.Tensor`): The query tensor.
        k (`torch.Tensor`): The key tensor.
        cos (`torch.Tensor`): The cosine part of the rotary embedding.
        sin (`torch.Tensor`): The sine part of the rotary embedding.
        position_ids (`torch.Tensor`, *optional*):
            Deprecated and unused.
        unsqueeze_dim (`int`, *optional*, defaults to 1):
            The 'unsqueeze_dim' argument specifies the dimension along which to unsqueeze cos[position_ids] and
            sin[position_ids] so that they can be properly broadcasted to the dimensions of q and k. For example, note
            that cos[position_ids] and sin[position_ids] have the shape [batch_size, seq_len, head_dim]. Then, if q and
            k have the shape [batch_size, heads, seq_len, head_dim], then setting unsqueeze_dim=1 makes
            cos[position_ids] and sin[position_ids] broadcastable to the shapes of q and k. Similarly, if q and k have
            the shape [batch_size, seq_len, heads, head_dim], then set unsqueeze_dim=2.
    Returns:
        `tuple(torch.Tensor)` comprising of the query and key tensors rotated using the Rotary Position Embedding.
    """
    # glm rope style (with full dim) and full precision
    original_dtype = q.dtype
    cos = cos.unsqueeze(unsqueeze_dim)
    sin = sin.unsqueeze(unsqueeze_dim)

    # Interleave them instead of usual shape
    cos = cos[..., : cos.shape[-1] // 2].repeat_interleave(2, dim=-1)
    sin = sin[..., : sin.shape[-1] // 2].repeat_interleave(2, dim=-1)

    q_embed = (q.float() * cos) + (rotate_half(q).float() * sin)
    k_embed = (k.float() * cos) + (rotate_half(k).float() * sin)

    return q_embed.to(original_dtype), k_embed.to(original_dtype)


def apply_multimodal_rotary_pos_emb(q, k, cos, sin, mrope_section, unsqueeze_dim=1):
    """Applies Rotary Position Embedding with Multimodal Sections to the query and key tensors (https://qwenlm.github.io/blog/qwen2-vl/).

    Explanation:
        Multimodal 3D rotary position embedding is an extension to 1D rotary position embedding. The input embedding
        sequence contains vision (images / videos) embedding and text embedding or just contains text embedding. For
        vision embedding part, we apply rotary position embedding on temporal, height and width dimension separately.
        Here we split the channel dimension to 3 chunks for the temporal, height and width rotary position embedding.
        For text embedding part, we just apply 1D rotary position embedding. The three rotary position index (temporal,
        height and width) of text embedding is always the same, so the text embedding rotary position embedding has no
        difference with modern LLMs.

    Args:
        q (`torch.Tensor`): The query tensor.
        k (`torch.Tensor`): The key tensor.
        cos (`torch.Tensor`): The cosine part of the rotary embedding.
        sin (`torch.Tensor`): The sine part of the rotary embedding.
        position_ids (`torch.Tensor`):
            The position indices of the tokens corresponding to the query and key tensors. For example, this can be
            used to pass offsetted position ids when working with a KV-cache.
        mrope_section(`List(int)`):
            Multimodal rope section is for channel dimension of temporal, height and width in rope calculation.
        unsqueeze_dim (`int`, *optional*, defaults to 1):
            The 'unsqueeze_dim' argument specifies the dimension along which to unsqueeze cos[position_ids] and
            sin[position_ids] so that they can be properly broadcasted to the dimensions of q and k. For example, note
            that cos[position_ids] and sin[position_ids] have the shape [batch_size, seq_len, head_dim]. Then, if q and
            k have the shape [batch_size, heads, seq_len, head_dim], then setting unsqueeze_dim=1 makes
            cos[position_ids] and sin[position_ids] broadcastable to the shapes of q and k. Similarly, if q and k have
            the shape [batch_size, seq_len, heads, head_dim], then set unsqueeze_dim=2.
    Returns:
        `tuple(torch.Tensor)` comprising of the query and key tensors rotated using the Rotary Position Embedding.
    """
    mrope_section = mrope_section * 2
    cos = torch.cat(
        [m[i % 3] for i, m in enumerate(cos.split(mrope_section, dim=-1))], dim=-1
    ).unsqueeze(unsqueeze_dim)
    sin = torch.cat(
        [m[i % 3] for i, m in enumerate(sin.split(mrope_section, dim=-1))], dim=-1
    ).unsqueeze(unsqueeze_dim)

    q_embed = (q * cos) + (rotate_half(q) * sin)
    k_embed = (k * cos) + (rotate_half(k) * sin)
    return q_embed, k_embed


class Ernie4_5Attention(nn.Module):
    """Multi-headed attention from 'Attention Is All You Need' paper"""

    def __init__(self, config: PaddleOCRVLConfig, layer_idx: int):
        super().__init__()
        self.config = config
        self.layer_idx = layer_idx
        self.head_dim = getattr(
            config, "head_dim", config.hidden_size // config.num_attention_heads
        )
        self.num_key_value_groups = (
            config.num_attention_heads // config.num_key_value_heads
        )
        self.scaling = self.head_dim**-0.5
        self.rope_scaling = config.rope_scaling
        self.attention_dropout = 0.0
        self.is_causal = True
        self.q_proj = nn.Linear(
            config.hidden_size,
            config.num_attention_heads * self.head_dim,
            bias=config.use_bias,
        )
        self.k_proj = nn.Linear(
            config.hidden_size,
            config.num_key_value_heads * self.head_dim,
            bias=config.use_bias,
        )
        self.v_proj = nn.Linear(
            config.hidden_size,
            config.num_key_value_heads * self.head_dim,
            bias=config.use_bias,
        )
        self.o_proj = nn.Linear(
            config.num_attention_heads * self.head_dim,
            config.hidden_size,
            bias=config.use_bias,
        )

    def forward(
        self,
        hidden_states: torch.Tensor,
        position_embeddings: tuple[torch.Tensor, torch.Tensor],
        attention_mask: Optional[torch.Tensor],
        past_key_value: Optional[Cache] = None,
        cache_position: Optional[torch.LongTensor] = None,
        **kwargs: Unpack[TransformersKwargs],
    ) -> tuple[torch.Tensor, torch.Tensor]:
        input_shape = hidden_states.shape[:-1]
        hidden_shape = (*input_shape, -1, self.head_dim)

        query_states = self.q_proj(hidden_states).view(hidden_shape).transpose(1, 2)
        key_states = self.k_proj(hidden_states).view(hidden_shape).transpose(1, 2)
        value_states = self.v_proj(hidden_states).view(hidden_shape).transpose(1, 2)

        if "position_ids" in kwargs and kwargs["position_ids"] is not None:
            position_ids = kwargs["position_ids"]
            if position_ids.dim() == 3 and position_ids.shape[0] > 1:
                kwargs["position_ids"] = position_ids[0:1]

        cos, sin = position_embeddings
        query_states, key_states = apply_multimodal_rotary_pos_emb(
            query_states, key_states, cos, sin, self.rope_scaling["mrope_section"]
        )

        if past_key_value is not None:
            # sin and cos are specific to RoPE models; cache_position needed for the static cache
            cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position}
            key_states, value_states = past_key_value.update(
                key_states, value_states, self.layer_idx, cache_kwargs
            )

        attention_interface: Callable = eager_attention_forward_ernie
        if self.config._attn_implementation != "eager":
            attention_interface = ALL_ATTENTION_FUNCTIONS[
                self.config._attn_implementation
            ]

        attn_output, attn_weights = attention_interface(
            self,
            query_states,
            key_states,
            value_states,
            attention_mask,
            dropout=0.0 if not self.training else self.attention_dropout,
            scaling=self.scaling,
            **kwargs,
        )

        attn_output = attn_output.reshape(*input_shape, -1).contiguous()
        attn_output = self.o_proj(attn_output)
        return attn_output, attn_weights


@use_kernel_forward_from_hub("RMSNorm")
class Ernie4_5RMSNorm(nn.Module):
    def __init__(self, hidden_size, eps=1e-6):
        """
        Ernie4_5RMSNorm is equivalent to T5LayerNorm
        """
        super().__init__()
        self.weight = nn.Parameter(torch.ones(hidden_size))
        self.variance_epsilon = eps

    def forward(self, hidden_states):
        input_dtype = hidden_states.dtype
        hidden_states = hidden_states.to(torch.float32)
        variance = hidden_states.pow(2).mean(-1, keepdim=True)
        hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon)
        return self.weight * hidden_states.to(input_dtype)

    def extra_repr(self):
        return f"{tuple(self.weight.shape)}, eps={self.variance_epsilon}"


class Ernie4_5DecoderLayer(GradientCheckpointingLayer):
    def __init__(self, config: PaddleOCRVLConfig, layer_idx: int):
        super().__init__()
        self.hidden_size = config.hidden_size

        self.self_attn = Ernie4_5Attention(config=config, layer_idx=layer_idx)

        self.mlp = Ernie4_5MLP(config)
        self.input_layernorm = Ernie4_5RMSNorm(
            config.hidden_size, eps=config.rms_norm_eps
        )
        self.post_attention_layernorm = Ernie4_5RMSNorm(
            config.hidden_size, eps=config.rms_norm_eps
        )

    def forward(
        self,
        hidden_states: torch.Tensor,
        attention_mask: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.LongTensor] = None,
        past_key_value: Optional[Cache] = None,
        use_cache: Optional[bool] = False,
        cache_position: Optional[torch.LongTensor] = None,
        position_embeddings: Optional[
            tuple[torch.Tensor, torch.Tensor]
        ] = None,  # necessary, but kept here for BC
        **kwargs: Unpack[TransformersKwargs],
    ) -> tuple[torch.Tensor]:
        residual = hidden_states
        hidden_states = self.input_layernorm(hidden_states)
        # Self Attention
        hidden_states, _ = self.self_attn(
            hidden_states=hidden_states,
            attention_mask=attention_mask,
            position_ids=position_ids,
            past_key_value=past_key_value,
            use_cache=use_cache,
            cache_position=cache_position,
            position_embeddings=position_embeddings,
            **kwargs,
        )
        hidden_states = residual + hidden_states

        # Fully Connected
        residual = hidden_states
        hidden_states = self.post_attention_layernorm(hidden_states)
        hidden_states = self.mlp(hidden_states)
        hidden_states = residual + hidden_states
        return hidden_states


@auto_docstring
class Ernie4_5PreTrainedModel(PreTrainedModel):
    config: PaddleOCRVLConfig
    base_model_prefix = "model"
    supports_gradient_checkpointing = True
    _no_split_modules = ["Ernie4_5DecoderLayer"]
    _skip_keys_device_placement = ["past_key_values"]
    _supports_flash_attn = True
    _supports_sdpa = True
    _supports_flex_attn = True

    _can_compile_fullgraph = True
    _supports_attention_backend = True
    _can_record_outputs = {
        "hidden_states": Ernie4_5DecoderLayer,
        "attentions": Ernie4_5Attention,
    }


@auto_docstring
class Ernie4_5Model(Ernie4_5PreTrainedModel):
    def __init__(self, config: PaddleOCRVLConfig):
        super().__init__(config)
        self.padding_idx = config.pad_token_id
        self.vocab_size = config.vocab_size

        self.embed_tokens = nn.Embedding(
            config.vocab_size, config.hidden_size, self.padding_idx
        )
        self.layers = nn.ModuleList(
            [
                Ernie4_5DecoderLayer(config, layer_idx)
                for layer_idx in range(config.num_hidden_layers)
            ]
        )
        self.norm = Ernie4_5RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
        self.rotary_emb = RotaryEmbedding(config=config)
        self.gradient_checkpointing = False

        # Initialize weights and apply final processing
        self.post_init()

    @check_model_inputs
    def forward(
        self,
        input_ids: Optional[torch.LongTensor] = None,
        attention_mask: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.LongTensor] = None,
        past_key_values: Optional[Cache] = None,
        inputs_embeds: Optional[torch.FloatTensor] = None,
        cache_position: Optional[torch.LongTensor] = None,
        use_cache: Optional[bool] = None,
        output_attentions: Optional[bool] = None,
        **kwargs: Unpack[TransformersKwargs],
    ) -> BaseModelOutputWithPast:
        if (input_ids is None) ^ (inputs_embeds is not None):
            raise ValueError(
                "You must specify exactly one of input_ids or inputs_embeds"
            )

        if inputs_embeds is None:
            inputs_embeds: torch.Tensor = self.embed_tokens(input_ids)

        if use_cache and past_key_values is None:
            past_key_values = DynamicCache()

        if cache_position is None:
            past_seen_tokens = (
                past_key_values.get_seq_length() if past_key_values is not None else 0
            )
            cache_position: torch.Tensor = torch.arange(
                past_seen_tokens,
                past_seen_tokens + inputs_embeds.shape[1],
                device=inputs_embeds.device,
            )

        if position_ids is None:
            position_ids = cache_position.view(1, 1, -1).expand(
                3, inputs_embeds.shape[0], -1
            )
        elif position_ids.dim() == 2:
            position_ids = position_ids[None, ...].expand(3, position_ids.shape[0], -1)

        causal_mask = create_causal_mask(
            config=self.config,
            inputs_embeds=inputs_embeds,
            attention_mask=attention_mask,
            past_key_values=past_key_values,
            position_ids=position_ids,
            cache_position=cache_position,
        )

        hidden_states = inputs_embeds
        position_embeddings = self.rotary_emb(hidden_states, position_ids)

        for decoder_layer in self.layers[: self.config.num_hidden_layers]:
            hidden_states = decoder_layer(
                hidden_states,
                attention_mask=causal_mask,
                position_ids=position_ids,
                past_key_value=past_key_values,
                cache_position=cache_position,
                position_embeddings=position_embeddings,
                **kwargs,
            )

        hidden_states = self.norm(hidden_states)
        return BaseModelOutputWithPast(
            last_hidden_state=hidden_states,
            past_key_values=past_key_values,
        )


class Ernie4_5ForCausalLM(Ernie4_5PreTrainedModel, GenerationMixin):
    _tied_weights_keys = ["lm_head.weight"]
    _tp_plan = {"lm_head": "colwise_rep"}
    _pp_plan = {"lm_head": (["hidden_states"], ["logits"])}

    def __init__(self, config):
        super().__init__(config)
        self.model = Ernie4_5Model(config)
        self.vocab_size = config.vocab_size
        self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False)

        # Initialize weights and apply final processing
        self.post_init()

    def set_decoder(self, decoder):
        self.model = decoder

    def get_decoder(self):
        return self.model

    @can_return_tuple
    def forward(
        self,
        input_ids: Optional[torch.LongTensor] = None,
        attention_mask: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.LongTensor] = None,
        past_key_values: Optional[Cache] = None,
        inputs_embeds: Optional[torch.FloatTensor] = None,
        labels: Optional[torch.LongTensor] = None,
        use_cache: Optional[bool] = None,
        cache_position: Optional[torch.LongTensor] = None,
        logits_to_keep: Union[int, torch.Tensor] = 0,
        **kwargs: Unpack[TransformersKwargs],
    ) -> CausalLMOutputWithPast:
        r"""
        labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
            Labels for computing the masked language modeling loss. Indices should either be in `[0, ...,
            config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored
            (masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`.
        """
        outputs: BaseModelOutputWithPast = self.model(
            input_ids=input_ids,
            attention_mask=attention_mask,
            position_ids=position_ids,
            past_key_values=past_key_values,
            inputs_embeds=inputs_embeds,
            use_cache=use_cache,
            cache_position=cache_position,
            **kwargs,
        )

        hidden_states = outputs.last_hidden_state
        # Only compute necessary logits, and do not upcast them to float if we are not computing the loss
        slice_indices = (
            slice(-logits_to_keep, None)
            if isinstance(logits_to_keep, int)
            else logits_to_keep
        )
        logits = self.lm_head(hidden_states[:, slice_indices, :])

        loss = None
        if labels is not None:
            loss = self.loss_function(
                logits=logits,
                labels=labels,
                vocab_size=self.config.vocab_size,
                **kwargs,
            )

        return CausalLMOutputWithPast(
            loss=loss,
            logits=logits,
            past_key_values=outputs.past_key_values,
            hidden_states=outputs.hidden_states,
            attentions=outputs.attentions,
        )


def _trunc_normal_(tensor, mean, std, a, b):
    # Cut & paste from PyTorch official master until it's in a few official releases - RW
    # Method based on https://people.sc.fsu.edu/~jburkardt/presentations/truncated_normal.pdf
    def norm_cdf(x):
        # Computes standard normal cumulative distribution function
        return (1.0 + math.erf(x / math.sqrt(2.0))) / 2.0

    if (mean < a - 2 * std) or (mean > b + 2 * std):
        warnings.warn(
            "mean is more than 2 std from [a, b] in nn.init.trunc_normal_. "
            "The distribution of values may be incorrect.",
            stacklevel=2,
        )

    # Values are generated by using a truncated uniform distribution and
    # then using the inverse CDF for the normal distribution.
    # Get upper and lower cdf values
    l = norm_cdf((a - mean) / std)
    u = norm_cdf((b - mean) / std)

    # Uniformly fill tensor with values from [l, u], then translate to
    # [2l-1, 2u-1].
    tensor.uniform_(2 * l - 1, 2 * u - 1)

    # Use inverse cdf transform for normal distribution to get truncated
    # standard normal
    tensor.erfinv_()

    # Transform to proper mean, std
    tensor.mul_(std * math.sqrt(2.0))
    tensor.add_(mean)

    # Clamp to ensure it's in the proper range
    tensor.clamp_(min=a, max=b)


def trunc_normal_tf_(
    tensor: torch.Tensor,
    mean: float = 0.0,
    std: float = 1.0,
    a: float = -2.0,
    b: float = 2.0,
) -> torch.Tensor:
    """Fills the input Tensor with values drawn from a truncated
    normal distribution. The values are effectively drawn from the
    normal distribution :math:`\\mathcal{N}(\text{mean}, \text{std}^2)`
    with values outside :math:`[a, b]` redrawn until they are within
    the bounds. The method used for generating the random values works
    best when :math:`a \\leq \text{mean} \\leq b`.

    NOTE: this 'tf' variant behaves closer to Tensorflow / JAX impl where the
    bounds [a, b] are applied when sampling the normal distribution with mean=0, std=1.0
    and the result is subsequently scaled and shifted by the mean and std args.

    Args:
        tensor: an n-dimensional `torch.Tensor`
        mean: the mean of the normal distribution
        std: the standard deviation of the normal distribution
        a: the minimum cutoff value
        b: the maximum cutoff value
    """
    with torch.no_grad():
        _trunc_normal_(tensor, 0, 1.0, a, b)
        tensor.mul_(std).add_(mean)


def variance_scaling_(tensor, scale=1.0, mode="fan_in", distribution="normal"):
    fan_in, fan_out = _calculate_fan_in_and_fan_out(tensor)
    if mode == "fan_in":
        denom = fan_in
    elif mode == "fan_out":
        denom = fan_out
    elif mode == "fan_avg":
        denom = (fan_in + fan_out) / 2

    variance = scale / denom

    if distribution == "truncated_normal":
        # constant is stddev of standard normal truncated to (-2, 2)
        trunc_normal_tf_(tensor, std=math.sqrt(variance) / 0.87962566103423978)
    elif distribution == "normal":
        with torch.no_grad():
            tensor.normal_(std=math.sqrt(variance))
    elif distribution == "uniform":
        bound = math.sqrt(3 * variance)
        with torch.no_grad():
            tensor.uniform_(-bound, bound)
    else:
        raise ValueError(f"invalid distribution {distribution}")


def lecun_normal_(tensor):
    variance_scaling_(tensor, mode="fan_in", distribution="truncated_normal")


def default_flax_embed_init(tensor):
    variance_scaling_(tensor, mode="fan_in", distribution="normal")


class Projector(nn.Module):

    def __init__(self, text_config: PaddleOCRVLConfig, vision_config: PaddleOCRVisionConfig):
        super().__init__()
        self.text_config = text_config
        self.vision_config = vision_config
        self.merge_kernel_size = (2, 2)

        self.hidden_size = (
            self.vision_config.hidden_size
            * self.merge_kernel_size[0]
            * self.merge_kernel_size[1]
        )

        self.pre_norm = torch.nn.LayerNorm(self.vision_config.hidden_size, eps=1e-05)
        self.linear_1 = nn.Linear(self.hidden_size, self.hidden_size, bias=True)
        self.act = GELUActivation()
        self.linear_2 = nn.Linear(
            self.hidden_size, self.text_config.hidden_size, bias=True
        )

    def forward(
        self, image_features: torch.Tensor, image_grid_thw: List[Tuple[int, int, int]]
    ) -> torch.Tensor:
        m1, m2 = self.merge_kernel_size
        if isinstance(image_features, (list, tuple)):
            processed_features = list()
            for image_feature, image_grid in zip(image_features, image_grid_thw):
                image_feature = self.pre_norm(image_feature)
                t, h, w = image_grid
                from einops import rearrange

                image_feature = rearrange(
                    image_feature,
                    "(t h p1 w p2) d -> (t h w) (p1 p2 d)",
                    t=t,
                    h=h // m1,
                    p1=m1,
                    w=w // m2,
                    p2=m2,
                )
                hidden_states = self.linear_1(image_feature)
                hidden_states = self.act(hidden_states)
                hidden_states = self.linear_2(hidden_states)
                processed_features.append(hidden_states)

            return processed_features

        dims = image_features.shape[:-1]
        dim = image_features.shape[-1]
        image_features = image_features.view(np.prod(dims), dim)
        hidden_states = self.pre_norm(image_features).view(-1, self.hidden_size)
        hidden_states = self.linear_1(hidden_states)
        hidden_states = self.act(hidden_states)
        hidden_states = self.linear_2(hidden_states)

        return hidden_states.view(*dims, -1)


class PaddleOCRVisionEmbeddings(nn.Module):
    def __init__(self, config: PaddleOCRVisionConfig):
        super().__init__()
        self.config = config
        self.embed_dim = config.hidden_size
        self.image_size = config.image_size
        self.patch_size = config.patch_size

        self.patch_embedding = nn.Conv2d(
            in_channels=config.num_channels,
            out_channels=self.embed_dim,
            kernel_size=self.patch_size,
            stride=self.patch_size,
            padding="valid",
        )

        self.num_patches = (self.image_size // self.patch_size) ** 2
        self.num_positions = self.num_patches
        self.cache_position_embedding = dict()
        self.cache_position_count = dict()
        self.position_embedding = nn.Embedding(self.num_positions, self.embed_dim)
        self.packing_position_embedding = nn.Embedding(32768, self.embed_dim)

        self.register_buffer(
            "position_ids",
            torch.arange(self.num_positions).expand((1, -1)),
            persistent=False,
        )

    def interpolate_pos_encoding(
        self,
        embeddings: torch.Tensor,
        height: int,
        width: int,
        is_after_patchify: bool = False,
    ) -> torch.Tensor:
        """
        This method allows to interpolate the pre-trained position encodings, to be able to use the model on higher resolution
        images. This method is also adapted to support torch.jit tracing and no class embeddings.

        Adapted from:
        - https://github.com/facebookresearch/dino/blob/de9ee3df6cf39fac952ab558447af1fa1365362a/vision_transformer.py#L174-L194, and
        - https://github.com/facebookresearch/dinov2/blob/e1277af2ba9496fbadf7aec6eba56e8d882d1e35/dinov2/models/vision_transformer.py#L179-L211
        """
        num_positions = self.position_embedding.weight.shape[0]

        patch_pos_embed = self.position_embedding.weight.unsqueeze(0)

        dim = embeddings.shape[-1]

        if is_after_patchify:
            new_height = height
            new_width = width
        else:
            new_height = height // self.patch_size
            new_width = width // self.patch_size

        sqrt_num_positions = torch_int(num_positions**0.5)
        patch_pos_embed = patch_pos_embed.reshape(
            1, sqrt_num_positions, sqrt_num_positions, dim
        )
        patch_pos_embed = patch_pos_embed.permute(0, 3, 1, 2)

        patch_pos_embed = nn.functional.interpolate(
            patch_pos_embed,
            size=(new_height, new_width),
            mode="bilinear",
            align_corners=False,
        )

        patch_pos_embed = patch_pos_embed.permute(0, 2, 3, 1).view(1, -1, dim)
        return patch_pos_embed

    @staticmethod
    def flatten_list(image_grid_thw):
        tmp_image_grid_thw = list()
        for image_grid in image_grid_thw:
            if isinstance(image_grid, list):
                tmp_image_grid_thw.extend(image_grid)
            else:
                tmp_image_grid_thw.append(image_grid)
        return tmp_image_grid_thw

    def fetch_position_embedding_lfu_cache(self, embeddings, h, w, max_cache=20):
        grid = (h, w)
        if grid in self.cache_position_embedding:
            self.cache_position_count[grid] += 1
            return self.cache_position_embedding[grid]

        if len(self.cache_position_embedding) >= max_cache:
            min_hit_grid = min(
                self.cache_position_count, key=self.cache_position_count.get
            )
            self.cache_position_count.pop(min_hit_grid)
            self.cache_position_embedding.pop(min_hit_grid)

        position_embedding = self.interpolate_pos_encoding(embeddings, h, w, True)
        self.cache_position_count[grid] = 1
        self.cache_position_embedding[grid] = position_embedding
        return position_embedding

    def forward(
        self,
        pixel_values: torch.FloatTensor,
        position_ids: Optional[torch.Tensor] = None,
        image_grid_thw: Optional[
            List[Union[Tuple[int, int, int], List[Tuple[int, int, int]]]]
        ] = None,
        interpolate_pos_encoding=False,
    ) -> torch.Tensor:
        if pixel_values.dim() == 5:
            assert position_ids is not None
            from einops import rearrange

            batch_size, squence_len, channel, height, width = pixel_values.shape
            target_dtype = self.patch_embedding.weight.dtype
            pixel_values = rearrange(pixel_values, "b l c h w -> (b l) c h w")
            patch_embeds = self.patch_embedding(
                pixel_values.to(dtype=target_dtype)
            )  # shape = [*, width, grid, grid]
            embeddings = patch_embeds.flatten(-2).squeeze(-1)
            embeddings = rearrange(
                embeddings, "(b l) d -> b l d", b=batch_size, l=squence_len
            )

            # todo: not dubug
            if interpolate_pos_encoding and image_grid_thw is not None:
                flatten_image_grid_thw = self.flatten_list(image_grid_thw)
                assert batch_size == 1
                start = 0
                image_embedding_list = list()
                assert (
                    sum([np.prod(x) for x in flatten_image_grid_thw])
                    == embeddings.shape[1]
                ), (flatten_image_grid_thw, embeddings.shape)
                embeddings = embeddings.squeeze(0)
                tmp_embeddings = list()
                for image_grid in image_grid_thw:
                    t, h, w = image_grid
                    end = start + t * h * w
                    image_embeddings = embeddings[start:end, :]
                    position_embedding = (
                        self.interpolate_pos_encoding(image_embeddings, h, w, True)
                        .squeeze(0)
                        .repeat(t, 1)
                    )
                    image_embeddings = image_embeddings + position_embedding
                    tmp_embeddings.append(image_embeddings)
                    start = end
                embeddings = torch.concat(tmp_embeddings, dim=0).unsqueeze(0)
            else:
                embeddings = embeddings + self.packing_position_embedding(position_ids)
            return embeddings
        else:
            raise NotImplementedError(str(pixel_values.shape))


def eager_attention_forward(
    module: nn.Module,
    query: torch.Tensor,
    key: torch.Tensor,
    value: torch.Tensor,
    attention_mask: Optional[torch.Tensor],
    scaling: float,
    dropout: float = 0.0,
    **kwargs,
):
    attn_weights = torch.matmul(query, key.transpose(-1, -2)) * scaling
    if attention_mask is not None:
        attn_weights = attn_weights + attention_mask

    attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(
        query.dtype
    )
    attn_weights = nn.functional.dropout(
        attn_weights, p=dropout, training=module.training
    )

    attn_output = torch.matmul(attn_weights, value)
    attn_output = attn_output.transpose(1, 2).contiguous()

    return attn_output, attn_weights


class PaddleOCRAttention(nn.Module):
    """Multi-headed attention from 'Attention Is All You Need' paper"""

    def __init__(self, config: PaddleOCRVisionConfig):
        super().__init__()
        self.config = config
        self.embed_dim = config.hidden_size
        self.num_heads = config.num_attention_heads
        self.head_dim = self.embed_dim // self.num_heads
        if self.head_dim * self.num_heads != self.embed_dim:
            raise ValueError(
                f"embed_dim must be divisible by num_heads (got `embed_dim`: {self.embed_dim} and `num_heads`:"
                f" {self.num_heads})."
            )
        self.scale = self.head_dim**-0.5
        self.dropout = config.attention_dropout
        self.is_causal = False

        self.k_proj = nn.Linear(self.embed_dim, self.embed_dim)
        self.v_proj = nn.Linear(self.embed_dim, self.embed_dim)
        self.q_proj = nn.Linear(self.embed_dim, self.embed_dim)
        self.out_proj = nn.Linear(self.embed_dim, self.embed_dim)

    def forward(
        self,
        hidden_states: torch.Tensor,
        attention_mask: Optional[torch.Tensor] = None,
        output_attentions: Optional[bool] = False,
        cu_seqlens: Optional[List[torch.Tensor]] = None,
        rope_emb: Optional[Tuple[torch.Tensor, torch.Tensor]] = None,
    ) -> Tuple[torch.Tensor, Optional[torch.Tensor]]:
        """Input shape: Batch x Time x Channel"""

        use_flash_attn = (
            cu_seqlens is not None
        ) and self.config._attn_implementation == "flash_attention_2"

        batch_size, seq_length, embed_dim = hidden_states.shape

        queries = self.q_proj(hidden_states)
        keys = self.k_proj(hidden_states)
        values = self.v_proj(hidden_states)

        if rope_emb is None:
            queries = queries.view(
                batch_size, seq_length, self.num_heads, self.head_dim
            ).transpose(1, 2)
            keys = keys.view(
                batch_size, seq_length, self.num_heads, self.head_dim
            ).transpose(1, 2)
            values = values.view(
                batch_size, seq_length, self.num_heads, self.head_dim
            ).transpose(1, 2)
        else:
            assert cu_seqlens is not None, "Rope support flash attn only."
            cos, sin = rope_emb
            queries = queries.view(
                batch_size, seq_length, self.num_heads, self.head_dim
            )
            keys = keys.view(batch_size, seq_length, self.num_heads, self.head_dim)
            if use_flash_attn:
                queries, keys = apply_rotary_pos_emb_flashatt(queries, keys, cos, sin)
            else:
                queries, keys = apply_rotary_pos_emb_vision(queries, keys, cos, sin)
            queries = queries.transpose(1, 2)
            keys = keys.transpose(1, 2)
            values = values.view(
                batch_size, seq_length, self.num_heads, self.head_dim
            ).transpose(1, 2)

        if not use_flash_attn:
            attention_interface: Callable = eager_attention_forward
            if self.config._attn_implementation != "eager":
                if self.config._attn_implementation == "sdpa" and output_attentions:
                    warnings.warn(
                        "`torch.nn.functional.scaled_dot_product_attention` does not support `output_attentions=True`. Falling back to "
                        'eager attention. This warning can be removed using the argument `attn_implementation="eager"` when loading the model.'
                    )
                elif self.config._attn_implementation == "sdpa":
                    attention_interface = sdpa_attention_forward

            attn_output, attn_weights = attention_interface(
                self,
                queries,
                keys,
                values,
                attention_mask,
                is_causal=self.is_causal,
                scaling=self.scale,
                dropout=0.0 if not self.training else self.dropout,
            )
            attn_output = attn_output.reshape(
                batch_size, seq_length, embed_dim
            ).contiguous()
        else:
            assert batch_size == 1, hidden_states.shape
            queries = queries.transpose(1, 2).squeeze(0)
            keys = keys.transpose(1, 2).squeeze(0)
            values = values.transpose(1, 2).squeeze(0)

            max_seqlen_q = (cu_seqlens[1:] - cu_seqlens[:-1]).max().item()
            max_seqlen_k = (cu_seqlens[1:] - cu_seqlens[:-1]).max().item()
            assert (
                cu_seqlens[-1].item()
                == queries.shape[0]
                == keys.shape[0]
                == values.shape[0]
            ), (cu_seqlens, queries.shape, keys.shape, values.shape)

            attn_output = flash_attn_varlen_func(
                queries,
                keys,
                values,
                cu_seqlens,
                cu_seqlens,
                max_seqlen_q,
                max_seqlen_k,
                causal=False,
                softmax_scale=self.scale,
            )
            attn_output = attn_output.flatten(-2).unsqueeze(0)
            attn_weights = None

        attn_output = self.out_proj(attn_output)

        if not output_attentions:
            attn_weights = None

        return attn_output, attn_weights


# Copied from transformers.models.clip.modeling_clip.CLIPMLP with CLIP->PaddleOCR
class PaddleOCRMLP(nn.Module):
    def __init__(self, config):
        super().__init__()
        self.config = config
        self.activation_fn = ACT2FN[config.hidden_act]
        self.fc1 = nn.Linear(config.hidden_size, config.intermediate_size)
        self.fc2 = nn.Linear(config.intermediate_size, config.hidden_size)

    def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
        hidden_states = self.fc1(hidden_states)
        hidden_states = self.activation_fn(hidden_states)
        hidden_states = self.fc2(hidden_states)
        return hidden_states


class PaddleOCREncoderLayer(nn.Module):
    def __init__(self, config: PaddleOCRVisionConfig):
        super().__init__()
        self.embed_dim = config.hidden_size
        self.layer_norm1 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
        self.self_attn = PaddleOCRAttention(config)
        self.layer_norm2 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
        self.mlp = PaddleOCRMLP(config)

    def forward(
        self,
        hidden_states: torch.Tensor,
        attention_mask: torch.Tensor,
        output_attentions: Optional[bool] = False,
        cu_seqlens: Optional[List[torch.Tensor]] = None,
        rope_emb: Optional[Tuple[torch.Tensor, torch.Tensor]] = None,
    ) -> Tuple[torch.FloatTensor]:
        """
        Args:
            hidden_states (`torch.FloatTensor`):
                Input to the layer of shape `(batch, seq_len, embed_dim)`.
            attention_mask (`torch.FloatTensor`):
                Attention mask of shape `(batch, 1, q_len, k_v_seq_len)` where padding elements are indicated by very large negative values.
            output_attentions (`bool`, *optional*, defaults to `False`):
                Whether or not to return the attentions tensors of all attention layers. See `attentions` under
                returned tensors for more detail.
        """
        residual = hidden_states

        hidden_states = self.layer_norm1(hidden_states)
        hidden_states, attn_weights = self.self_attn(
            hidden_states=hidden_states,
            attention_mask=attention_mask,
            output_attentions=output_attentions,
            cu_seqlens=cu_seqlens,
            rope_emb=rope_emb,
        )
        hidden_states = residual + hidden_states

        residual = hidden_states
        hidden_states = self.layer_norm2(hidden_states)
        hidden_states = self.mlp(hidden_states)
        hidden_states = residual + hidden_states

        outputs = (hidden_states,)

        if output_attentions:
            outputs += (attn_weights,)

        return outputs


class PaddleOCRPreTrainedModel(PreTrainedModel):
    config_class = PaddleOCRVLConfig
    base_model_prefix = "PaddleOCR"
    supports_gradient_checkpointing = True

    _no_split_modules = [
        "PaddleOCRTextEmbeddings",
        "PaddleOCREncoderLayer",
        "PaddleOCRVisionEmbeddings",
        "PaddleOCRMultiheadAttentionPoolingHead",
    ]
    _supports_flash_attn_2 = True
    _supports_sdpa = True

    def _init_weights(self, module):
        """Initialize the weights"""
        if isinstance(module, PaddleOCRVisionEmbeddings):
            width = (
                self.config.vision_config.hidden_size
                if isinstance(self.config, PaddleOCRVLConfig)
                else self.config.hidden_size
            )
            nn.init.normal_(module.position_embedding.weight, std=1 / np.sqrt(width))
        elif isinstance(module, nn.Embedding):
            default_flax_embed_init(module.weight)
        elif isinstance(module, PaddleOCRAttention):
            nn.init.xavier_uniform_(module.q_proj.weight)
            nn.init.xavier_uniform_(module.k_proj.weight)
            nn.init.xavier_uniform_(module.v_proj.weight)
            nn.init.xavier_uniform_(module.out_proj.weight)
            nn.init.zeros_(module.q_proj.bias)
            nn.init.zeros_(module.k_proj.bias)
            nn.init.zeros_(module.v_proj.bias)
            nn.init.zeros_(module.out_proj.bias)
        elif isinstance(module, PaddleOCRMLP):
            nn.init.xavier_uniform_(module.fc1.weight)
            nn.init.xavier_uniform_(module.fc2.weight)
            nn.init.normal_(module.fc1.bias, std=1e-6)
            nn.init.normal_(module.fc2.bias, std=1e-6)
        elif isinstance(module, PaddleOCRMultiheadAttentionPoolingHead):
            nn.init.xavier_uniform_(module.probe.data)
            nn.init.xavier_uniform_(module.attention.in_proj_weight.data)
            nn.init.zeros_(module.attention.in_proj_bias.data)
        elif isinstance(module, (nn.Linear, nn.Conv2d)):
            lecun_normal_(module.weight)
            if module.bias is not None:
                nn.init.zeros_(module.bias)
        elif isinstance(module, nn.LayerNorm):
            module.bias.data.zero_()
            module.weight.data.fill_(1.0)


# Copied from transformers.models.altclip.modeling_altclip.AltCLIPEncoder with AltCLIP->PaddleOCR
class PaddleOCREncoder(nn.Module):
    """
    Transformer encoder consisting of `config.num_hidden_layers` self attention layers. Each layer is a
    [`PaddleOCREncoderLayer`].

    Args:
        config: PaddleOCRVLConfig
    """

    def __init__(self, config: PaddleOCRVLConfig):
        super().__init__()
        self.config = config
        embed_dim = config.hidden_size
        num_heads = config.num_attention_heads
        head_dim = embed_dim // num_heads
        self.layers = nn.ModuleList(
            [PaddleOCREncoderLayer(config) for _ in range(config.num_hidden_layers)]
        )
        self.rotary_pos_emb = SigLIPRotaryEmbedding(head_dim // 2)
        self.gradient_checkpointing = False

    @staticmethod
    def flatten_list(image_grid_thw):
        tmp_image_grid_thw = list()
        for image_grid in image_grid_thw:
            if isinstance(image_grid, list):
                tmp_image_grid_thw.extend(image_grid)
            else:
                tmp_image_grid_thw.append(image_grid)
        return tmp_image_grid_thw

    def build_window_index(self, image_grid, window_size, device):
        from einops import rearrange

        window_indices = list()
        pad_values = -100
        start_window_index = 0
        cu_seqlens_within_windows = list()

        for t, h, w in image_grid:
            window_index = torch.arange(t * h * w, device=device).reshape(t, h, w)
            pad_h = (-h) % window_size
            pad_w = (-w) % window_size
            assert pad_h >= 0 and pad_w >= 0, (pad_h, pad_w)
            window_index = F.pad(window_index, (0, pad_w, 0, pad_h), value=pad_values)
            window_index = rearrange(
                window_index,
                "t (h p1) (w p2) -> t (h w) (p1 p2)",
                p1=window_size,
                p2=window_size,
            )
            window_seqlens = (window_index != pad_values).long().sum(-1).reshape(-1)
            window_index = window_index.reshape(-1)
            window_index = window_index[window_index != pad_values]
            window_indices.append(window_index + start_window_index)
            cu_seqlens_within_windows.append(
                window_seqlens.cumsum(0) + start_window_index
            )
            start_window_index += t * h * w
        window_indices = torch.concat(window_indices, dim=0)
        cu_seqlens_within_windows = torch.concat(cu_seqlens_within_windows, dim=0)
        cu_seqlens_within_windows = F.pad(
            cu_seqlens_within_windows, (1, 0), value=0
        ).to(torch.int32)
        return window_indices, cu_seqlens_within_windows

    # Ignore copy
    # @can_return_tuple
    def forward(
        self,
        inputs_embeds,
        attention_mask: Optional[torch.Tensor] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        cu_seqlens: Optional[List[torch.Tensor]] = None,
        image_grid_thw: Optional[
            List[Union[Tuple[int, int, int], List[Tuple[int, int, int]]]]
        ] = None,
        height_position_ids: Optional[torch.Tensor] = None,
        width_position_ids: Optional[torch.Tensor] = None,
        use_rope: Optional[bool] = False,
        window_size: Optional[bool] = -1,
        vision_or_text: str = "vision",
    ) -> BaseModelOutput:
        r"""
        Args:
            inputs_embeds (`torch.FloatTensor` of shape `(batch_size, sequence_length, hidden_size)`):
                Optionally, instead of passing `input_ids` you can choose to directly pass an embedded representation.
                This is useful if you want more control over how to convert `input_ids` indices into associated vectors
                than the model's internal embedding lookup matrix.
            attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
                Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`:

                - 1 for tokens that are **not masked**,
                - 0 for tokens that are **masked**.

                [What are attention masks?](../glossary#attention-mask)
            output_attentions (`bool`, *optional*):
                Whether or not to return the attentions tensors of all attention layers. See `attentions` under
                returned tensors for more detail.
            output_hidden_states (`bool`, *optional*):
                Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors
                for more detail.
            return_dict (`bool`, *optional*):
                Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
        """

        vision_or_text = "vision"
        assert vision_or_text in ["vision", "text"]
        use_window_attn = window_size > 0 and vision_or_text == "vision"
        use_rope = (use_rope is True) and (vision_or_text == "vision")
        output_attentions = (
            output_attentions
            if output_attentions is not None
            else self.config.output_attentions
        )
        output_hidden_states = (
            output_hidden_states
            if output_hidden_states is not None
            else self.config.output_hidden_states
        )

        encoder_states = () if output_hidden_states else None
        all_attentions = () if output_attentions else None

        device = inputs_embeds.device
        hidden_states = inputs_embeds
        attention_mask = (
            attention_mask.to(inputs_embeds.dtype)
            if attention_mask is not None
            else None
        )
        if use_rope is True:
            flatten_image_grid_thw = self.flatten_list(image_grid_thw)
            assert (
                sum([np.prod(x) for x in flatten_image_grid_thw])
                == hidden_states.shape[1]
            ), (flatten_image_grid_thw, hidden_states.shape)

            if width_position_ids is None or height_position_ids is None:
                split_hids = list()
                split_wids = list()
                for t, h, w in flatten_image_grid_thw:
                    image_pids = torch.arange(t * h * w, device=device) % (h * w)
                    sample_hids = image_pids // w
                    sample_wids = image_pids % w
                    split_hids.append(sample_hids)
                    split_wids.append(sample_wids)
                width_position_ids = torch.concat(split_wids, dim=0)
                height_position_ids = torch.concat(split_hids, dim=0)

            window_indices, cu_seqlens_within_windows = None, None

            if use_window_attn:
                window_indices, cu_seqlens_within_windows = self.build_window_index(
                    flatten_image_grid_thw, window_size, device
                )
                reversed_window_indices = window_indices.argsort()
                height_position_ids = height_position_ids[window_indices]
                width_position_ids = width_position_ids[window_indices]

            pids = torch.stack([height_position_ids, width_position_ids], dim=-1)
            max_grid_size = pids.max() + 1
            rope_emb_max_grid = self.rotary_pos_emb(max_grid_size)
            rope_emb = rope_emb_max_grid[pids].flatten(1)
            rope_emb = rope_emb.repeat(1, 2)
            rope_emb = (rope_emb.cos(), rope_emb.sin())
        else:

            rope_emb = None
            window_indices, cu_seqlens_within_windows = None, None

            if use_window_attn:
                flatten_image_grid_thw = self.flatten_list(image_grid_thw)
                assert (
                    sum([np.prod(x) for x in flatten_image_grid_thw])
                    == hidden_states.shape[1]
                ), (flatten_image_grid_thw, hidden_states.shape)

                window_indices, cu_seqlens_within_windows = self.build_window_index(
                    flatten_image_grid_thw, window_size, device
                )
                reversed_window_indices = window_indices.argsort()

        if use_window_attn:
            assert cu_seqlens_within_windows is not None
            attn_cu_seqlens = cu_seqlens_within_windows
            hidden_states = hidden_states[:, window_indices, :]
        else:
            attn_cu_seqlens = cu_seqlens

        for encoder_layer in self.layers:
            if output_hidden_states:
                encoder_states = encoder_states + (
                    (hidden_states[:, reversed_window_indices, :],)
                    if use_window_attn
                    else (hidden_states,)
                )
            if self.gradient_checkpointing and self.training:
                layer_outputs = self._gradient_checkpointing_func(
                    encoder_layer.__call__,
                    hidden_states,
                    attention_mask,
                    output_attentions,
                    attn_cu_seqlens,
                    rope_emb,
                )
            else:
                layer_outputs = encoder_layer(
                    hidden_states,
                    attention_mask,
                    output_attentions=output_attentions,
                    cu_seqlens=attn_cu_seqlens,
                    rope_emb=rope_emb,
                )

            hidden_states = layer_outputs[0]

            if output_attentions:
                all_attentions = all_attentions + (layer_outputs[1],)

        if use_window_attn:
            hidden_states = hidden_states[:, reversed_window_indices, :]

        if output_hidden_states:
            encoder_states = encoder_states + (hidden_states,)

        return BaseModelOutput(
            last_hidden_state=hidden_states,
            hidden_states=encoder_states,
            attentions=all_attentions,
        )


class PaddleOCRVisionTransformer(nn.Module):
    def __init__(self, config: PaddleOCRVisionConfig):
        super().__init__()
        self.config = config
        embed_dim = config.hidden_size

        self.embeddings = PaddleOCRVisionEmbeddings(config)
        self.encoder = PaddleOCREncoder(config)
        self.post_layernorm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
        self.use_head = (
            True if not hasattr(config, "vision_use_head") else config.vision_use_head
        )
        if self.use_head:
            self.head = PaddleOCRMultiheadAttentionPoolingHead(config)

    # @can_return_tuple
    def forward(
        self,
        pixel_values,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        interpolate_pos_encoding: Optional[bool] = False,
        attention_mask: Optional[torch.Tensor] = None,
        sample_indices: Optional[torch.Tensor] = None,
        image_indices: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.Tensor] = None,
        height_position_ids: Optional[torch.Tensor] = None,
        width_position_ids: Optional[torch.Tensor] = None,
        cu_seqlens: Optional[List[torch.Tensor]] = None,
        padding_mask: Optional[torch.Tensor] = None,
        vision_return_embed_list: Optional[bool] = False,
        image_grid_thw: Optional[
            List[Union[Tuple[int, int, int], List[Tuple[int, int, int]]]]
        ] = None,
        return_pooler_output: Optional[bool] = True,
        use_rope: Optional[bool] = False,
        window_size: Optional[bool] = -1,
    ) -> BaseModelOutputWithPooling:
        r"""
        Returns:

        """
        output_attentions = (
            output_attentions
            if output_attentions is not None
            else self.config.output_attentions
        )
        output_hidden_states = (
            output_hidden_states
            if output_hidden_states is not None
            else self.config.output_hidden_states
        )
        hidden_states = self.embeddings(
            pixel_values,
            interpolate_pos_encoding=interpolate_pos_encoding,
            position_ids=position_ids,
            image_grid_thw=image_grid_thw,
        )

        encoder_outputs: BaseModelOutput = self.encoder(
            inputs_embeds=hidden_states,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            attention_mask=attention_mask,
            cu_seqlens=cu_seqlens,
            image_grid_thw=image_grid_thw,
            use_rope=use_rope,
            height_position_ids=height_position_ids,
            width_position_ids=width_position_ids,
            window_size=window_size,
            vision_or_text="vision",
        )

        last_hidden_state = encoder_outputs.last_hidden_state
        last_hidden_state = self.post_layernorm(last_hidden_state)

        if return_pooler_output is True:
            if sample_indices is not None:
                assert self.use_head is True
                dim = last_hidden_state.shape[-1]
                sample_hidden_state_list = list()

                hidden_state = last_hidden_state.squeeze(0)
                sample_index = sample_indices
                unique_sample_index = torch.unique(sample_index).sort().values.unbind(0)
                unique_sample_index = list(unique_sample_index)
                if len(unique_sample_index) > 0 and unique_sample_index[0] == -1:
                    unique_sample_index = unique_sample_index[1:]
                for sample_idx in unique_sample_index:
                    token_indices = (sample_index == sample_idx).nonzero().flatten()
                    sample_hidden_state = hidden_state[token_indices]
                    sample_hidden_state_list.append(sample_hidden_state)

                if not vision_return_embed_list:
                    max_length = max(
                        [_state.shape[0] for _state in sample_hidden_state_list]
                    )
                    tmp_sample_hidden_state_list = list()
                    padding_mask = list()
                    for idx, _state in enumerate(sample_hidden_state_list):
                        padding_length = max_length - _state.shape[0]
                        mask = _state.new_zeros(size=(max_length,), dtype=torch.int64)
                        mask[-padding_length:] = 1
                        padding_mask.append(mask)
                        padding = _state.new_zeros(size=(padding_length, dim))
                        new_state = torch.concat([_state, padding], dim=0)
                        tmp_sample_hidden_state_list.append(new_state)
                    sample_hidden_state = torch.stack(
                        tmp_sample_hidden_state_list, dim=0
                    )
                    padding_mask = (
                        torch.stack(padding_mask, dim=0)
                        .float()
                        .to(last_hidden_state.dtype)
                    )
                    pooler_output = self.head(
                        sample_hidden_state, key_padding_mask=padding_mask
                    )
                else:
                    pooler_output = list()
                    for state in sample_hidden_state_list:
                        sample_pooler_output = self.head(state.unsqueeze(0))
                        pooler_output.append(sample_pooler_output)
                    pooler_output = torch.concat(pooler_output, dim=0)
                    sample_hidden_state = sample_hidden_state_list

                return BaseModelOutputWithPooling(
                    last_hidden_state=sample_hidden_state,
                    pooler_output=pooler_output,
                    hidden_states=encoder_outputs.hidden_states,
                    attentions=encoder_outputs.attentions,
                )
            else:
                pooler_output = self.head(last_hidden_state) if self.use_head else None

            return BaseModelOutputWithPooling(
                last_hidden_state=last_hidden_state,
                pooler_output=pooler_output,
                hidden_states=encoder_outputs.hidden_states,
                attentions=encoder_outputs.attentions,
            )

        sample_hidden_state = list()
        assert cu_seqlens is not None
        for i in range(cu_seqlens.shape[0] - 1):
            start = cu_seqlens[i]
            end = cu_seqlens[i + 1]
            tensor = last_hidden_state[:, start:end, :].squeeze(0)
            sample_hidden_state.append(tensor)

        return BaseModelOutputWithPooling(
            last_hidden_state=sample_hidden_state,
            pooler_output=None,
            hidden_states=encoder_outputs.hidden_states,
            attentions=encoder_outputs.attentions,
        )


class PaddleOCRMultiheadAttentionPoolingHead(nn.Module):
    """Multihead Attention Pooling."""

    def __init__(self, config: PaddleOCRVisionConfig):
        super().__init__()

        self.probe = nn.Parameter(torch.randn(1, 1, config.hidden_size))
        self.attention = torch.nn.MultiheadAttention(
            config.hidden_size, config.num_attention_heads, batch_first=True
        )
        self.layernorm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
        self.mlp = PaddleOCRMLP(config)

    def forward(self, hidden_state, key_padding_mask=None):
        batch_size = hidden_state.shape[0]
        probe = self.probe.repeat(batch_size, 1, 1)

        hidden_state = self.attention(
            probe, hidden_state, hidden_state, key_padding_mask=key_padding_mask
        )[0]

        residual = hidden_state
        hidden_state = self.layernorm(hidden_state)
        hidden_state = residual + self.mlp(hidden_state)

        return hidden_state[:, 0]


class PaddleOCRVisionModel(PaddleOCRPreTrainedModel):
    config_class = PaddleOCRVisionConfig
    main_input_name = "pixel_values"

    def __init__(self, config: PaddleOCRVisionConfig):
        super().__init__(config)

        self.vision_model = PaddleOCRVisionTransformer(config)

        # Initialize weights and apply final processing
        self.post_init()

    def get_input_embeddings(self) -> nn.Module:
        return self.vision_model.embeddings.patch_embedding

    # @can_return_tuple
    def forward(
        self,
        pixel_values,
        sample_indices: Optional[torch.Tensor] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        interpolate_pos_encoding: bool = False,
        position_ids: Optional[torch.Tensor] = None,
        vision_return_embed_list: Optional[bool] = False,
        image_grid_thw: Optional[
            List[Union[Tuple[int, int, int], List[Tuple[int, int, int]]]]
        ] = None,
        cu_seqlens: Optional[List[torch.Tensor]] = None,
        return_pooler_output: Optional[bool] = True,
        use_rope: Optional[bool] = False,
        window_size: Optional[bool] = -1,
    ) -> BaseModelOutputWithPooling:
        return self.vision_model(
            pixel_values=pixel_values,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            interpolate_pos_encoding=interpolate_pos_encoding,
            position_ids=position_ids,
            vision_return_embed_list=vision_return_embed_list,
            image_grid_thw=image_grid_thw,
            sample_indices=sample_indices,
            cu_seqlens=cu_seqlens,
            return_pooler_output=return_pooler_output,
            use_rope=use_rope,
            window_size=window_size,
        )


def apply_rotary_pos_emb_flashatt(
    q: torch.Tensor, k: torch.Tensor, cos: torch.Tensor, sin: torch.Tensor
) -> Tuple[torch.Tensor, torch.Tensor]:
    cos = cos.chunk(2, dim=-1)[0].contiguous()
    sin = sin.chunk(2, dim=-1)[0].contiguous()
    q_embed = apply_rotary_emb(q.float(), cos.float(), sin.float()).type_as(q)
    k_embed = apply_rotary_emb(k.float(), cos.float(), sin.float()).type_as(k)
    return q_embed, k_embed


def rotate_half(x):
    """Rotates half the hidden dims of the input."""
    x1 = x[..., : x.shape[-1] // 2]
    x2 = x[..., x.shape[-1] // 2 :]
    return torch.cat((-x2, x1), dim=-1)


def apply_rotary_pos_emb_vision(
    q: torch.Tensor, k: torch.Tensor, cos: torch.Tensor, sin: torch.Tensor
) -> Tuple[torch.Tensor, torch.Tensor]:
    orig_q_dtype = q.dtype
    orig_k_dtype = k.dtype
    q, k = q.float(), k.float()
    cos, sin = cos.unsqueeze(-2).float(), sin.unsqueeze(-2).float()
    q_embed = (q * cos) + (rotate_half(q) * sin)
    k_embed = (k * cos) + (rotate_half(k) * sin)
    q_embed = q_embed.to(orig_q_dtype)
    k_embed = k_embed.to(orig_k_dtype)
    return q_embed, k_embed


class SigLIPRotaryEmbedding(nn.Module):
    def __init__(self, dim: int, theta: float = 10000.0) -> None:
        super().__init__()
        self.dim = dim
        self.theta = theta
        self.rope_init()

    def rope_init(self):
        inv_freq = 1.0 / (
            self.theta ** (torch.arange(0, self.dim, 2, dtype=torch.float) / self.dim)
        )
        self.register_buffer("inv_freq", inv_freq, persistent=False)

    def forward(self, seqlen: int) -> torch.Tensor:
        seq = torch.arange(
            seqlen, device=self.inv_freq.device, dtype=self.inv_freq.dtype
        )
        freqs = torch.outer(seq, self.inv_freq)
        return freqs


@dataclass
class PaddleOCRVLCausalLMOutputWithPast(ModelOutput):
    """
    Base class for PaddleOCRVL causal language model (or autoregressive) outputs.

    Args:
        loss (`torch.FloatTensor` of shape `(1,)`, *optional*, returned when `labels` is provided):
            Language modeling loss (for next-token prediction).
        logits (`torch.FloatTensor` of shape `(batch_size, sequence_length, config.vocab_size)`):
            Prediction scores of the language modeling head (scores for each vocabulary token before SoftMax).
        past_key_values (`tuple(tuple(torch.FloatTensor))`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`):
            Tuple of `tuple(torch.FloatTensor)` of length `config.n_layers`, with each tuple having 2 tensors of shape
            `(batch_size, num_heads, sequence_length, embed_size_per_head)`)

            Contains pre-computed hidden-states (key and values in the self-attention blocks) that can be used (see
            `past_key_values` input) to speed up sequential decoding.
        hidden_states (`tuple(torch.FloatTensor)`, *optional*, returned when `output_hidden_states=True` is passed or when `config.output_hidden_states=True`):
            Tuple of `torch.FloatTensor` (one for the output of the embeddings, if the model has an embedding layer, +
            one for the output of each layer) of shape `(batch_size, sequence_length, hidden_size)`.

            Hidden-states of the model at the output of each layer plus the optional initial embedding outputs.
        attentions (`tuple(torch.FloatTensor)`, *optional*, returned when `output_attentions=True` is passed or when `config.output_attentions=True`):
            Tuple of `torch.FloatTensor` (one for each layer) of shape `(batch_size, num_heads, sequence_length,
            sequence_length)`.

            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
            heads.
        rope_deltas (`torch.LongTensor` of shape `(batch_size, )`, *optional*):
            The rope index difference between sequence length and multimodal rope.
    """

    loss: Optional[torch.FloatTensor] = None
    logits: torch.FloatTensor = None
    past_key_values: Optional[List[torch.FloatTensor]] = None
    hidden_states: Optional[Tuple[torch.FloatTensor]] = None
    attentions: Optional[Tuple[torch.FloatTensor]] = None
    rope_deltas: Optional[torch.LongTensor] = None


class PaddleOCRVLForConditionalGeneration(Ernie4_5PreTrainedModel, GenerationMixin):
    _tied_weights_keys = ["lm_head.weight"]
    config_class = PaddleOCRVLConfig
    _no_split_modules = ["Ernie4_5_DecoderLayer", "PaddleOCREncoderLayer"]

    def __init__(self, config):
        super().__init__(config)
        self.mlp_AR = Projector(config, config.vision_config)
        self.visual = PaddleOCRVisionModel(config.vision_config)
        self.model = Ernie4_5Model(config)
        self.vocab_size = config.vocab_size
        self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False)
        self.rope_deltas = None

        self.post_init()

    def get_input_embeddings(self):
        return self.model.embed_tokens

    def set_input_embeddings(self, value):
        self.model.embed_tokens = value

    def get_output_embeddings(self):
        return self.lm_head

    def set_output_embeddings(self, new_embeddings):
        self.lm_head = new_embeddings

    def set_decoder(self, decoder):
        self.model = decoder

    def get_decoder(self):
        return self.model

    def get_rope_index(
        self,
        input_ids: Optional[torch.LongTensor] = None,
        image_grid_thw: Optional[torch.LongTensor] = None,
        video_grid_thw: Optional[torch.LongTensor] = None,
        second_per_grid_ts: Optional[torch.Tensor] = None,
        attention_mask: Optional[torch.Tensor] = None,
    ) -> Tuple[torch.Tensor, torch.Tensor]:
        """
        Calculate the 3D rope index based on image and video's temporal, height and width in LLM.

        Explanation:
            Each embedding sequence contains vision embedding and text embedding or just contains text embedding.

            For pure text embedding sequence, the rotary position embedding has no difference with modern LLMs.
            Examples:
                input_ids: [T T T T T], here T is for text.
                temporal position_ids: [0, 1, 2, 3, 4]
                height position_ids: [0, 1, 2, 3, 4]
                width position_ids: [0, 1, 2, 3, 4]

            For vision and text embedding sequence, we calculate 3D rotary position embedding for vision part
            and 1D rotary position embedding for text part.
            Examples:
                Temporal (Time): 3 patches, representing different segments of the video in time.
                Height: 2 patches, dividing each frame vertically.
                Width: 2 patches, dividing each frame horizontally.
                We also have some important parameters:
                fps (Frames Per Second): The video's frame rate, set to 1. This means one frame is processed each second.
                tokens_per_second: This is a crucial parameter. It dictates how many "time-steps" or "temporal tokens" are conceptually packed into a one-second interval of the video. In this case, we have 25 tokens per second. So each second of the video will be represented with 25 separate time points. It essentially defines the temporal granularity.
                temporal_patch_size: The number of frames that compose one temporal patch. Here, it's 2 frames.
                interval: The step size for the temporal position IDs, calculated as tokens_per_second * temporal_patch_size / fps. In this case, 25 * 2 / 1 = 50. This means that each temporal patch will be have a difference of 50 in the temporal position IDs.
                input_ids: [V V V V V V V V V V V V T T T T T], here V is for vision.
                vision temporal position_ids: [0, 0, 0, 0, 50, 50, 50, 50, 100, 100, 100, 100]
                vision height position_ids: [0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1]
                vision width position_ids: [0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1]
                text temporal position_ids: [101, 102, 103, 104, 105]
                text height position_ids: [101, 102, 103, 104, 105]
                text width position_ids: [101, 102, 103, 104, 105]
                Here we calculate the text start position_ids as the max vision position_ids plus 1.

        Args:
            input_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`):
                Indices of input sequence tokens in the vocabulary. Padding will be ignored by default should you provide
                it.
            image_grid_thw (`torch.LongTensor` of shape `(num_images, 3)`, *optional*):
                The temporal, height and width of feature shape of each image in LLM.
            video_grid_thw (`torch.LongTensor` of shape `(num_videos, 3)`, *optional*):
                The temporal, height and width of feature shape of each video in LLM.
            second_per_grid_ts (`torch.Tensor` of shape `(num_videos)`, *optional*):
                The time interval (in seconds) for each grid along the temporal dimension in the 3D position IDs.
            attention_mask (`torch.Tensor` of shape `(batch_size, sequence_length)`, *optional*):
                Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`:

                - 1 for tokens that are **not masked**,
                - 0 for tokens that are **masked**.

        Returns:
            position_ids (`torch.LongTensor` of shape `(3, batch_size, sequence_length)`)
            mrope_position_deltas (`torch.Tensor` of shape `(batch_size)`)
        """
        spatial_merge_size = self.config.vision_config.spatial_merge_size
        image_token_id = self.config.image_token_id
        video_token_id = self.config.video_token_id
        vision_start_token_id = self.config.vision_start_token_id
        mrope_position_deltas = []
        if input_ids is not None and (
            image_grid_thw is not None or video_grid_thw is not None
        ):
            total_input_ids = input_ids
            if attention_mask is None:
                attention_mask = torch.ones_like(total_input_ids)
            position_ids = torch.ones(
                3,
                input_ids.shape[0],
                input_ids.shape[1],
                dtype=input_ids.dtype,
                device=input_ids.device,
            )
            image_index, video_index = 0, 0
            attention_mask = attention_mask.to(total_input_ids.device)
            for i, input_ids in enumerate(total_input_ids):
                input_ids = input_ids[attention_mask[i] == 1]
                image_nums, video_nums = 0, 0
                vision_start_indices = torch.argwhere(
                    input_ids == vision_start_token_id
                ).squeeze(1)
                vision_tokens = input_ids[vision_start_indices + 1]
                image_nums = (vision_tokens == image_token_id).sum()
                video_nums = (vision_tokens == video_token_id).sum()
                input_tokens = input_ids.tolist()
                llm_pos_ids_list: list = []
                st = 0
                remain_images, remain_videos = image_nums, video_nums
                for _ in range(image_nums + video_nums):
                    if image_token_id in input_tokens and remain_images > 0:
                        ed_image = input_tokens.index(image_token_id, st)
                    else:
                        ed_image = len(input_tokens) + 1
                    if video_token_id in input_tokens and remain_videos > 0:
                        ed_video = input_tokens.index(video_token_id, st)
                    else:
                        ed_video = len(input_tokens) + 1
                    if ed_image < ed_video:
                        t, h, w = (
                            image_grid_thw[image_index][0],
                            image_grid_thw[image_index][1],
                            image_grid_thw[image_index][2],
                        )
                        second_per_grid_t = 0
                        image_index += 1
                        remain_images -= 1
                        ed = ed_image

                    else:
                        t, h, w = (
                            video_grid_thw[video_index][0],
                            video_grid_thw[video_index][1],
                            video_grid_thw[video_index][2],
                        )
                        if second_per_grid_ts is not None:
                            second_per_grid_t = second_per_grid_ts[video_index]
                        else:
                            second_per_grid_t = 1.0
                        video_index += 1
                        remain_videos -= 1
                        ed = ed_video
                    llm_grid_t, llm_grid_h, llm_grid_w = (
                        t.item(),
                        h.item() // spatial_merge_size,
                        w.item() // spatial_merge_size,
                    )
                    text_len = ed - st

                    st_idx = (
                        llm_pos_ids_list[-1].max() + 1
                        if len(llm_pos_ids_list) > 0
                        else 0
                    )
                    llm_pos_ids_list.append(
                        torch.arange(text_len).view(1, -1).expand(3, -1) + st_idx
                    )

                    if torch.is_tensor(second_per_grid_t):
                        second_per_grid_t = second_per_grid_t.detach().item()
                    range_tensor = torch.arange(llm_grid_t).view(-1, 1)
                    expanded_range = range_tensor.expand(-1, llm_grid_h * llm_grid_w)

                    time_tensor = (
                        expanded_range
                        * second_per_grid_t
                        * self.config.vision_config.tokens_per_second
                    )

                    time_tensor_long = time_tensor.long()
                    t_index = time_tensor_long.flatten()

                    h_index = (
                        torch.arange(llm_grid_h)
                        .view(1, -1, 1)
                        .expand(llm_grid_t, -1, llm_grid_w)
                        .flatten()
                    )
                    w_index = (
                        torch.arange(llm_grid_w)
                        .view(1, 1, -1)
                        .expand(llm_grid_t, llm_grid_h, -1)
                        .flatten()
                    )
                    llm_pos_ids_list.append(
                        torch.stack([t_index, h_index, w_index]) + text_len + st_idx
                    )
                    st = ed + llm_grid_t * llm_grid_h * llm_grid_w

                if st < len(input_tokens):
                    st_idx = (
                        llm_pos_ids_list[-1].max() + 1
                        if len(llm_pos_ids_list) > 0
                        else 0
                    )
                    text_len = len(input_tokens) - st
                    llm_pos_ids_list.append(
                        torch.arange(text_len).view(1, -1).expand(3, -1) + st_idx
                    )

                llm_positions = torch.cat(llm_pos_ids_list, dim=1).reshape(3, -1)
                position_ids[..., i, attention_mask[i] == 1] = llm_positions.to(
                    position_ids.device
                )
                mrope_position_deltas.append(
                    llm_positions.max() + 1 - len(total_input_ids[i])
                )
            mrope_position_deltas = torch.tensor(
                mrope_position_deltas, device=input_ids.device
            ).unsqueeze(1)
            return position_ids, mrope_position_deltas
        else:
            if attention_mask is not None:
                position_ids = attention_mask.long().cumsum(-1) - 1
                position_ids.masked_fill_(attention_mask == 0, 1)
                position_ids = (
                    position_ids.unsqueeze(0)
                    .expand(3, -1, -1)
                    .to(attention_mask.device)
                )
                max_position_ids = position_ids.max(0, keepdim=False)[0].max(
                    -1, keepdim=True
                )[0]
                mrope_position_deltas = max_position_ids + 1 - attention_mask.shape[-1]
            else:
                position_ids = (
                    torch.arange(input_ids.shape[1], device=input_ids.device)
                    .view(1, 1, -1)
                    .expand(3, input_ids.shape[0], -1)
                )
                mrope_position_deltas = torch.zeros(
                    [input_ids.shape[0], 1],
                    device=input_ids.device,
                    dtype=input_ids.dtype,
                )

            return position_ids, mrope_position_deltas

    def forward(
        self,
        input_ids: torch.LongTensor = None,
        attention_mask: Optional[torch.Tensor] = None,
        position_ids: Optional[torch.LongTensor] = None,
        past_key_values: Optional[List[torch.FloatTensor]] = None,
        inputs_embeds: Optional[torch.FloatTensor] = None,
        labels: Optional[torch.LongTensor] = None,
        use_cache: Optional[bool] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        return_dict: Optional[bool] = None,
        pixel_values: Optional[torch.Tensor] = None,
        pixel_values_videos: Optional[torch.FloatTensor] = None,
        image_grid_thw: Optional[torch.LongTensor] = None,
        video_grid_thw: Optional[torch.LongTensor] = None,
        rope_deltas: Optional[torch.LongTensor] = None,
        cache_position: Optional[torch.LongTensor] = None,
        second_per_grid_ts: Optional[torch.Tensor] = None,
        **kwargs,
    ) -> Union[Tuple, PaddleOCRVLCausalLMOutputWithPast]:
        r"""
        Returns:
        """
        output_attentions = (
            output_attentions
            if output_attentions is not None
            else self.config.output_attentions
        )
        output_hidden_states = (
            output_hidden_states
            if output_hidden_states is not None
            else self.config.output_hidden_states
        )
        return_dict = (
            return_dict if return_dict is not None else self.config.use_return_dict
        )

        if inputs_embeds is None:
            inputs_embeds = self.model.embed_tokens(input_ids)
            if pixel_values is not None:
                pixel_values = pixel_values.type(self.visual.dtype)
                pixel_values = pixel_values.unsqueeze(0)
                siglip_position_ids = list()
                image_grid_hws = list()
                sample_indices = list()
                cu_seqlens = [0]

                pro = 0
                for idx, thw in enumerate(image_grid_thw):
                    thw_tuple = tuple(thw.detach().cpu().numpy().tolist())
                    numel = np.prod(thw_tuple)
                    image_grid_hws.append(thw_tuple)
                    image_position_ids = torch.arange(numel) % np.prod(thw_tuple[1:])
                    siglip_position_ids.append(image_position_ids)
                    sample_indices.append(torch.full((numel,), idx, dtype=torch.int64))
                    cu_seqlens.append(cu_seqlens[-1] + numel)

                siglip_position_ids = torch.concat(siglip_position_ids, dim=0).to(
                    pixel_values.device
                )
                cu_seqlens = torch.tensor(cu_seqlens, dtype=torch.int32).to(
                    pixel_values.device
                )
                sample_indices = torch.concat(sample_indices, dim=0).to(
                    pixel_values.device
                )

                vision_outputs = self.visual(
                    pixel_values=pixel_values,
                    image_grid_thw=image_grid_hws,
                    position_ids=siglip_position_ids,
                    vision_return_embed_list=True,
                    interpolate_pos_encoding=True,
                    sample_indices=sample_indices,
                    cu_seqlens=cu_seqlens,
                    return_pooler_output=False,
                    use_rope=True,
                    window_size=-1,
                )
                image_embeds = vision_outputs.last_hidden_state

                image_embeds = self.mlp_AR(image_embeds, image_grid_thw)

                n_image_tokens = (input_ids == self.config.image_token_id).sum().item()
                # image_embeds is a list of tensor, each tensor is a image feature,I want to concat them all into a tensor
                image_embeds = torch.cat(image_embeds, dim=0)
                n_image_features = image_embeds.shape[0]
                if n_image_tokens != n_image_features:
                    raise ValueError(
                        f"Image features and image tokens do not match: tokens: {n_image_tokens}, features {n_image_features}"
                    )

                mask = input_ids == self.config.image_token_id
                mask_unsqueezed = mask.unsqueeze(-1)
                mask_expanded = mask_unsqueezed.expand_as(inputs_embeds)
                image_mask = mask_expanded.to(inputs_embeds.device)

                image_embeds = image_embeds.to(
                    inputs_embeds.device, inputs_embeds.dtype
                )

                inputs_embeds = inputs_embeds.masked_scatter(image_mask, image_embeds)

            if attention_mask is not None:
                attention_mask = attention_mask.to(inputs_embeds.device)
        # position_ids = None
        # if we get 4D attention mask we cannot calculate rope deltas anymore. TODO @raushan fixme
        if position_ids is None and (
            attention_mask is None or attention_mask.ndim == 2
        ):
            # calculate RoPE index once per generation in the pre-fill stage only
            if (
                (cache_position is not None and cache_position[0] == 0)
                or self.rope_deltas is None
                or (past_key_values is None or past_key_values.get_seq_length() == 0)
            ):
                position_ids, rope_deltas = self.get_rope_index(
                    input_ids,
                    image_grid_thw,
                    video_grid_thw,
                    second_per_grid_ts,
                    attention_mask,
                )
                self.rope_deltas = rope_deltas
            # then use the prev pre-calculated rope-deltas to get the correct position ids
            else:
                batch_size, seq_length, _ = inputs_embeds.shape
                delta = (
                    (cache_position[0] + self.rope_deltas).to(inputs_embeds.device)
                    if cache_position is not None
                    else 0
                )
                position_ids = torch.arange(seq_length, device=inputs_embeds.device)
                position_ids = position_ids.view(1, -1).expand(batch_size, -1)
                if cache_position is not None:  # otherwise `deltas` is an int `0`
                    delta = delta.repeat_interleave(batch_size // delta.shape[0], dim=0)
                position_ids = position_ids.add(delta)
                position_ids = position_ids.unsqueeze(0).expand(3, -1, -1)

        outputs = self.model(
            input_ids=None,
            position_ids=position_ids,
            attention_mask=attention_mask,
            past_key_values=past_key_values,
            inputs_embeds=inputs_embeds,
            use_cache=use_cache,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            return_dict=return_dict,
            **kwargs,
        )

        hidden_states = outputs[0]
        logits = self.lm_head(hidden_states)

        loss = None
        if labels is not None:
            # Upcast to float if we need to compute the loss to avoid potential precision issues
            logits = logits.float()
            # Shift so that tokens < n predict n
            shift_logits = logits[..., :-1, :].contiguous()
            shift_labels = labels[..., 1:].contiguous()
            # Flatten the tokens
            loss_fct = CrossEntropyLoss()
            shift_logits = shift_logits.view(-1, self.config.vocab_size)
            shift_labels = shift_labels.view(-1)
            # Enable model parallelism
            shift_labels = shift_labels.to(shift_logits.device)
            loss = loss_fct(shift_logits, shift_labels)

        if not return_dict:
            output = (logits,) + outputs[1:]
            return (loss,) + output if loss is not None else output

        return PaddleOCRVLCausalLMOutputWithPast(
            loss=loss,
            logits=logits,
            past_key_values=outputs.past_key_values,
            hidden_states=outputs.hidden_states,
            attentions=outputs.attentions,
            rope_deltas=self.rope_deltas,
        )

    def prepare_inputs_for_generation(
        self,
        input_ids,
        past_key_values=None,
        attention_mask=None,
        inputs_embeds=None,
        cache_position=None,
        position_ids=None,
        use_cache=True,
        pixel_values=None,
        pixel_values_videos=None,
        image_grid_thw=None,
        video_grid_thw=None,
        second_per_grid_ts=None,
        **kwargs,
    ):
        # Overwritten -- in specific circumstances we don't want to forward image inputs to the model

        model_inputs = super().prepare_inputs_for_generation(
            input_ids,
            past_key_values=past_key_values,
            attention_mask=attention_mask,
            inputs_embeds=inputs_embeds,
            cache_position=cache_position,
            position_ids=position_ids,
            pixel_values=pixel_values,
            pixel_values_videos=pixel_values_videos,
            image_grid_thw=image_grid_thw,
            video_grid_thw=video_grid_thw,
            second_per_grid_ts=second_per_grid_ts,
            use_cache=use_cache,
            **kwargs,
        )

        model_inputs["position_ids"] = None

        if cache_position[0] != 0:
            model_inputs["pixel_values"] = None
            model_inputs["pixel_values_videos"] = None

        return model_inputs

    def _get_image_nums_and_video_nums(
        self,
        input_ids: Optional[torch.LongTensor],
    ) -> Tuple[torch.Tensor, torch.Tensor]:
        """
        Get the number of images and videos for each sample to calculate the separation length of the sample tensor.
        These parameters are not passed through the processor to avoid unpredictable impacts from interface modifications.

        Args:
            input_ids (`torch.LongTensor` of shape `(batch_size, sequence_length)`):
                Indices of input sequence tokens in the vocabulary.

        Returns:
            image_nums (`torch.LongTensor` of shape `(batch_size, num_images_sample)`)
            video_nums (`torch.LongTensor` of shape `(batch_size, num_videos_sample)`)
        """
        image_token_id = self.config.image_token_id
        video_token_id = self.config.video_token_id
        vision_start_token_id = self.config.vision_start_token_id

        vision_start_mask = input_ids == vision_start_token_id
        vision_first_mask = torch.roll(vision_start_mask, shifts=1, dims=1)
        image_mask = input_ids == image_token_id
        video_mask = input_ids == video_token_id
        image_nums = torch.sum(vision_first_mask & image_mask, dim=1)
        video_nums = torch.sum(vision_first_mask & video_mask, dim=1)

        return image_nums, video_nums

    def _expand_inputs_for_generation(
        self,
        expand_size: int = 1,
        is_encoder_decoder: bool = False,
        input_ids: Optional[torch.LongTensor] = None,
        **model_kwargs,
    ) -> Tuple[torch.LongTensor, Dict[str, Any]]:
        # Overwritten -- Support for expanding tensors without a batch size dimension
        # e.g., pixel_values, image_grid_thw, pixel_values_videos, video_grid_thw, second_per_grid_t
        # pixel_values.shape[0] is sum(seqlen_images for samples)
        # image_grid_thw.shape[0] is sum(num_images for samples)

        if expand_size == 1:
            return input_ids, model_kwargs

        visual_keys = [
            "pixel_values",
            "image_grid_thw",
            "pixel_values_videos",
            "video_grid_thw",
            "second_per_grid_ts",
        ]

        def _expand_dict_for_generation_visual(dict_to_expand):
            image_grid_thw = model_kwargs.get("image_grid_thw", None)
            video_grid_thw = model_kwargs.get("video_grid_thw", None)
            image_nums, video_nums = self._get_image_nums_and_video_nums(input_ids)

            def _repeat_interleave_samples(x, lengths, repeat_times):
                samples = torch.split(x, lengths)
                repeat_args = [repeat_times] + [1] * (x.dim() - 1)
                result = torch.cat(
                    [sample.repeat(*repeat_args) for sample in samples], dim=0
                )
                return result

            for key in dict_to_expand:
                if key == "pixel_values":
                    # split images into samples
                    samples = torch.split(image_grid_thw, list(image_nums))
                    # compute the sequence length of images for each sample
                    lengths = [torch.prod(sample, dim=1).sum() for sample in samples]
                    dict_to_expand[key] = _repeat_interleave_samples(
                        dict_to_expand[key], lengths=lengths, repeat_times=expand_size
                    )
                elif key == "image_grid_thw":
                    # get the num of images for each sample
                    lengths = list(image_nums)
                    dict_to_expand[key] = _repeat_interleave_samples(
                        dict_to_expand[key], lengths=lengths, repeat_times=expand_size
                    )
                elif key == "pixel_values_videos":
                    samples = torch.split(video_grid_thw, list(video_nums))
                    lengths = [torch.prod(sample, dim=1).sum() for sample in samples]
                    dict_to_expand[key] = _repeat_interleave_samples(
                        dict_to_expand[key], lengths=lengths, repeat_times=expand_size
                    )
                elif key == "video_grid_thw":
                    lengths = list(video_nums)
                    dict_to_expand[key] = _repeat_interleave_samples(
                        dict_to_expand[key], lengths=lengths, repeat_times=expand_size
                    )
                elif key == "second_per_grid_ts":
                    if not isinstance(dict_to_expand[key], list):
                        raise TypeError(
                            f"Expected value for key '{key}' to be a list, but got {type(dict_to_expand[key])} instead."
                        )
                    tensor = torch.tensor(dict_to_expand[key])
                    lengths = list(video_nums)
                    tensor = _repeat_interleave_samples(
                        tensor, lengths=lengths, repeat_times=expand_size
                    )
                    dict_to_expand[key] = tensor.tolist()
            return dict_to_expand

        def _expand_dict_for_generation(dict_to_expand):
            for key in dict_to_expand:
                if (
                    key != "cache_position"
                    and dict_to_expand[key] is not None
                    and isinstance(dict_to_expand[key], torch.Tensor)
                    and key not in visual_keys
                ):
                    dict_to_expand[key] = dict_to_expand[key].repeat_interleave(
                        expand_size, dim=0
                    )
            return dict_to_expand

        # input_ids is required for expanding visual inputs
        # If input_ids is unavailable, visual inputs will not be used; therefore, there is no need to expand visual inputs.
        if input_ids is not None and input_ids.numel() != 0:
            model_kwargs = _expand_dict_for_generation_visual(model_kwargs)

        if input_ids is not None:
            input_ids = input_ids.repeat_interleave(expand_size, dim=0)

        model_kwargs = _expand_dict_for_generation(model_kwargs)

        if is_encoder_decoder:
            if model_kwargs.get("encoder_outputs") is None:
                raise ValueError(
                    "If `is_encoder_decoder` is True, make sure that `encoder_outputs` is defined."
                )
            model_kwargs["encoder_outputs"] = _expand_dict_for_generation(
                model_kwargs["encoder_outputs"]
            )

        return input_ids, model_kwargs
