# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project

# Adapted from
# https://github.com/zai-org/CogAgent
"""Inference-only CogAgent model compatible with THUDM weights."""

from argparse import Namespace
from collections.abc import Iterator, Mapping, Sequence
from typing import Annotated, Literal

import numpy as np
import torch
from torch import nn
from torch.nn import LayerNorm
from transformers import BatchFeature

from vllm.config import VllmConfig
from vllm.config.multimodal import BaseDummyOptions
from vllm.distributed import get_tensor_model_parallel_world_size
from vllm.model_executor.layers.activation import SiluAndMul, get_act_fn
from vllm.model_executor.layers.attention import MMEncoderAttention
from vllm.model_executor.layers.conv import Conv2dLayer
from vllm.model_executor.layers.linear import (
    ColumnParallelLinear,
    MergedColumnParallelLinear,
    QKVParallelLinear,
    ReplicatedLinear,
    RowParallelLinear,
)
from vllm.model_executor.layers.quantization import QuantizationConfig
from vllm.model_executor.models.module_mapping import MultiModelKeys
from vllm.multimodal import MULTIMODAL_REGISTRY
from vllm.multimodal.inputs import (
    MultiModalDataDict,
    MultiModalFeatureSpec,
    MultiModalFieldConfig,
    MultiModalKwargsItems,
)
from vllm.multimodal.parse import MultiModalDataItems
from vllm.multimodal.processing import (
    BaseDummyInputsBuilder,
    BaseMultiModalProcessor,
    BaseProcessingInfo,
    PromptReplacement,
    PromptUpdate,
)
from vllm.sequence import IntermediateTensors
from vllm.transformers_utils.configs.chatglm import ChatGLMConfig
from vllm.transformers_utils.processors.glm4v import (
    GLM4VImageProcessorFast,
    GLM4VProcessor,
)
from vllm.utils.tensor_schema import TensorSchema, TensorShape

from .chatglm import ChatGLMBaseModel, ChatGLMModel, GLMTransformer
from .interfaces import (
    MultiModalEmbeddings,
    SupportsLoRA,
    SupportsMRoPE,
    SupportsMultiModal,
    SupportsPP,
)


class GLMVImagePixelInputs(TensorSchema):
    """
    Dimensions:
        - b: Batch size
        - c: Number of channels (3)
        - h: Height of image
        - w: Width of image
    """

    type: Literal["pixel_values"] = "pixel_values"
    data: Annotated[torch.Tensor, TensorShape("b", 3, "h", "w")]


class EVA2CLIPPatchEmbedding(nn.Module):
    def __init__(self, config):
        super().__init__()
        self.proj = Conv2dLayer(
            config.in_channels,
            config.hidden_size,
            kernel_size=config.patch_size,
            stride=config.patch_size,
        )
        self.cls_embedding = nn.Parameter(torch.zeros(1, config.hidden_size))
        self.position_embedding = nn.Embedding(config.num_positions, config.hidden_size)

    def forward(self, images: torch.Tensor) -> torch.Tensor:
        """
        Parameters:
        images : torch.Tensor
            Input image tensor with shape (B, C, H, W)

        Returns:
        torch.Tensor
            Transformed tensor with shape (B, L, D)
        """
        images = images.to(device=self.proj.weight.device, dtype=self.proj.weight.dtype)
        x = self.proj(images)
        x = x.flatten(2).transpose(1, 2)
        cls_token = self.cls_embedding.expand(x.shape[0], -1, -1)
        x = torch.cat((cls_token, x), dim=1)
        x += self.position_embedding.weight.unsqueeze(0)
        return x


class EVA2CLIPAttention(nn.Module):
    def __init__(
        self,
        config,
        quant_config: QuantizationConfig | None = None,
        prefix: str = "",
    ):
        super().__init__()
        self.hidden_size = config.hidden_size
        self.tp_size = get_tensor_model_parallel_world_size()
        self.num_heads_per_rank = config.num_heads // self.tp_size
        self.head_dim = config.hidden_size // config.num_heads
        self.scale = self.head_dim**-0.5

        self.query_key_value = QKVParallelLinear(
            config.hidden_size,
            self.head_dim,
            config.num_heads,
            quant_config=quant_config,
            prefix=f"{prefix}.query_key_value",
        )
        self.dense = RowParallelLinear(
            config.hidden_size,
            config.hidden_size,
            quant_config=quant_config,
            prefix=f"{prefix}.dense",
        )

        self.attn = MMEncoderAttention(
            self.num_heads_per_rank,
            self.head_dim,
            self.scale,
            prefix=f"{prefix}.attn",
        )
        self.output_dropout = torch.nn.Dropout(config.dropout_prob)

    def forward(self, x: torch.Tensor) -> torch.Tensor:
        qkv, _ = self.query_key_value(x)  # B, L, 3 * H * D
        q, k, v = qkv.chunk(3, dim=-1)

        out = self.attn(q, k, v)
        output, _ = self.dense(out)
        output = self.output_dropout(output)
        return output


class EVA2CLIPMLP(nn.Module):
    def __init__(
        self,
        config,
        quant_config: QuantizationConfig | None = None,
        prefix: str = "",
    ):
        super().__init__()
        self.config = config
        self.activation_fn = get_act_fn(config.hidden_act)
        self.fc1 = ColumnParallelLinear(
            config.hidden_size,
            config.intermediate_size,
            quant_config=quant_config,
            prefix=f"{prefix}.fc1",
        )
        self.fc2 = RowParallelLinear(
            config.intermediate_size,
            config.hidden_size,
            quant_config=quant_config,
            prefix=f"{prefix}.fc2",
        )

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


class EVA2CLIPTransformerLayer(nn.Module):
    def __init__(
        self,
        config,
        quant_config: QuantizationConfig | None = None,
        prefix: str = "",
    ):
        super().__init__()
        self.input_layernorm = LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
        self.attention = EVA2CLIPAttention(
            config, quant_config=quant_config, prefix=f"{prefix}.attention"
        )
        self.mlp = EVA2CLIPMLP(
            config, quant_config=quant_config, prefix=f"{prefix}.mlp"
        )
        self.post_attention_layernorm = LayerNorm(
            config.hidden_size, eps=config.layer_norm_eps
        )

    def forward(self, hidden_states):
        attention_input = hidden_states
        attention_output = self.input_layernorm(self.attention(attention_input))
        hidden_states = attention_input + attention_output
        mlp_input = hidden_states
        mlp_output = self.post_attention_layernorm(self.mlp(mlp_input))
        output = mlp_input + mlp_output
        return output


class EVA2CLIPTransformer(nn.Module):
    def __init__(
        self,
        config,
        quant_config: QuantizationConfig | None = None,
        prefix: str = "",
    ):
        super().__init__()
        self.layers = nn.ModuleList(
            [
                EVA2CLIPTransformerLayer(
                    config,
                    quant_config=quant_config,
                    prefix=f"{prefix}.layers.{layer_idx}",
                )
                for layer_idx in range(config.num_hidden_layers)
            ]
        )

    def forward(self, hidden_states):
        for layer_module in self.layers:
            hidden_states = layer_module(hidden_states)
        return hidden_states


class EVA2CLIPGLU(nn.Module):
    def __init__(
        self,
        config,
        in_features,
        quant_config: QuantizationConfig | None = None,
        prefix: str = "",
    ):
        """
        The original implementation is the same as:
        ```python
        self.dense_h_to_4h = ColumnParallelLinear(
            config.hidden_size,
            config.ffn_hidden_size,
            bias=False,
            quant_config=quant_config,
        )

        self.gate_proj = ColumnParallelLinear(
            config.hidden_size,
            config.ffn_hidden_size,
            bias=False,
            quant_config=quant_config,
        )
        ```
        ```
        gate_proj_output, _ = self.gate_proj(x)
        dense_h_to_4h_output, _ = self.dense_h_to_4h(x)
        x = torch.cat([gate_proj_output, dense_h_to_4h_output], dim=-1)
        ```

        We merge two ColumnParallelLinear into one MergedColumnParallelLinear:
        ```
        self.merged_proj = MergedColumnParallelLinear(
            config.hidden_size,
            [config.ffn_hidden_size] * 2,
            bias=False,
            quant_config=quant_config,
        )
        ```
        ```
        x, _ = self.merged_proj(x)
        ```
        """
        super().__init__()
        self.linear_proj = ReplicatedLinear(
            in_features,
            config.hidden_size,
            bias=False,
            quant_config=quant_config,
            prefix=f"{prefix}.linear_proj",
        )
        self.norm1 = nn.LayerNorm(config.hidden_size)
        self.act1 = nn.GELU()
        self.act2 = SiluAndMul()

        self.merged_proj = MergedColumnParallelLinear(
            config.hidden_size,
            [config.ffn_hidden_size] * 2,
            bias=False,
            quant_config=quant_config,
            prefix=f"{prefix}.merged_proj",
        )

        self.dense_4h_to_h = RowParallelLinear(
            config.ffn_hidden_size,
            config.hidden_size,
            bias=False,
            quant_config=quant_config,
            prefix=f"{prefix}.dense_4h_to_h",
        )

    def forward(self, x):
        x, _ = self.linear_proj(x)
        x = self.act1(self.norm1(x))
        x, _ = self.merged_proj(x)
        x = self.act2(x)
        x, _ = self.dense_4h_to_h(x)
        return x


class EVA2CLIPModel(nn.Module):
    def __init__(
        self,
        config,
        quant_config: QuantizationConfig | None = None,
        prefix: str = "",
    ):
        super().__init__()
        vision_config = Namespace(**config.vision_config)
        self.patch_embedding = EVA2CLIPPatchEmbedding(vision_config)
        self.transformer = EVA2CLIPTransformer(
            vision_config, quant_config=quant_config, prefix=f"{prefix}.transformer"
        )
        self.linear_proj = EVA2CLIPGLU(
            config,
            in_features=config.hidden_size,
            quant_config=quant_config,
            prefix=f"{prefix}.linear_proj",
        )
        self.conv = Conv2dLayer(
            in_channels=vision_config.hidden_size,
            out_channels=config.hidden_size,
            kernel_size=2,
            stride=2,
        )
        self.boi = nn.Parameter(torch.zeros(1, 1, config.hidden_size))
        self.eoi = nn.Parameter(torch.zeros(1, 1, config.hidden_size))
        self.scaling_factor = vision_config.scaling_factor

    def forward(self, images: torch.Tensor) -> torch.Tensor:
        """
        Parameters:
        images : torch.Tensor
            Input image tensor with shape (B, C, H, W)

        Returns:
        torch.Tensor
            Transformed tensor with shape (B, L, D)
        """
        x = self.patch_embedding(images)
        x = self.transformer(x)
        x = x[:, 1:]

        b, s, h = x.shape
        grid_size = int(s**0.5)
        x = x.view(b, grid_size, grid_size, h).permute(0, 3, 1, 2)
        x = self.conv(x)

        x = x.flatten(2).transpose(1, 2)
        x = self.linear_proj(x)
        boi = self.boi.expand(x.shape[0], -1, -1)
        eoi = self.eoi.expand(x.shape[0], -1, -1)
        x = torch.cat((boi, x, eoi), dim=1)
        x = x / self.scaling_factor
        return x


class GLM4VModel(ChatGLMModel):
    def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
        super().__init__(vllm_config=vllm_config, prefix=prefix)

        quant_config = vllm_config.quant_config

        self.vision = EVA2CLIPModel(
            self.config, quant_config, prefix=f"{prefix}.vision"
        )


class GLM4VProcessingInfo(BaseProcessingInfo):
    def get_hf_config(self):
        return self.ctx.get_hf_config(ChatGLMConfig)

    def get_image_processor(self, **kwargs):
        config = self.get_hf_config()
        vision_config = config.vision_config

        image_size = vision_config["image_size"]
        kwargs.setdefault("size", {"width": image_size, "height": image_size})

        return GLM4VImageProcessorFast(**kwargs)

    def get_hf_processor(self, **kwargs: object) -> GLM4VProcessor:
        return self.ctx.init_processor(
            GLM4VProcessor,
            tokenizer=self.get_tokenizer(),
            image_processor=self.get_image_processor(**kwargs),
        )

    def get_supported_mm_limits(self) -> Mapping[str, int | None]:
        return {"image": 1}

    def get_num_image_tokens(self) -> int:
        hf_config = self.get_hf_config()
        vision_config = hf_config.vision_config

        image_size = vision_config["image_size"]
        patch_size = vision_config["patch_size"]
        grid_length = image_size // patch_size // 2
        return grid_length * grid_length

    def get_num_image_feature_tokens(self) -> int:
        # EVA2CLIPModel has embeddings for boi and eoi tokens as well
        return self.get_num_image_tokens() + 2


class GLM4VDummyInputsBuilder(BaseDummyInputsBuilder[GLM4VProcessingInfo]):
    def get_dummy_text(self, mm_counts: Mapping[str, int]) -> str:
        num_images = mm_counts.get("image", 0)

        base_text = "<|begin_of_image|><|endoftext|><|end_of_image|>"

        return base_text * num_images

    def get_dummy_mm_data(
        self,
        seq_len: int,
        mm_counts: Mapping[str, int],
        mm_options: Mapping[str, BaseDummyOptions],
    ) -> MultiModalDataDict:
        hf_config = self.info.get_hf_config()
        vision_config = hf_config.vision_config

        target_width = target_height = vision_config["image_size"]
        num_images = mm_counts.get("image", 0)

        image_overrides = mm_options.get("image")

        return {
            "image": self._get_dummy_images(
                width=target_width,
                height=target_height,
                num_images=num_images,
                overrides=image_overrides,
            )
        }


class GLM4VMultiModalProcessor(BaseMultiModalProcessor[GLM4VProcessingInfo]):
    def _hf_processor_applies_updates(
        self,
        prompt_text: str,
        mm_items: MultiModalDataItems,
        hf_processor_mm_kwargs: Mapping[str, object],
        tokenization_kwargs: Mapping[str, object],
    ) -> bool:
        return False

    def _get_mm_fields_config(
        self,
        hf_inputs: BatchFeature,
        hf_processor_mm_kwargs: Mapping[str, object],
    ) -> Mapping[str, MultiModalFieldConfig]:
        return dict(pixel_values=MultiModalFieldConfig.batched("image"))

    def _get_prompt_updates(
        self,
        mm_items: MultiModalDataItems,
        hf_processor_mm_kwargs: Mapping[str, object],
        out_mm_kwargs: MultiModalKwargsItems,
    ) -> Sequence[PromptUpdate]:
        hf_config = self.info.get_hf_config()

        boi_token_id = hf_config.boi_token_id
        image_token_id = hf_config.pad_token_id
        eoi_token_id = hf_config.eoi_token_id

        def get_replacement(item_idx: int):
            num_image_tokens = self.info.get_num_image_tokens()
            image_tokens = [image_token_id] * num_image_tokens

            return [boi_token_id] + image_tokens + [eoi_token_id]

        return [
            PromptReplacement(
                modality="image",
                target=[boi_token_id, image_token_id, eoi_token_id],
                replacement=get_replacement,
            ),
        ]


@MULTIMODAL_REGISTRY.register_processor(
    GLM4VMultiModalProcessor,
    info=GLM4VProcessingInfo,
    dummy_inputs=GLM4VDummyInputsBuilder,
)
class GLM4VForCausalLM(
    ChatGLMBaseModel, SupportsMultiModal, SupportsLoRA, SupportsPP, SupportsMRoPE
):
    packed_modules_mapping = {
        "query_key_value": ["query_key_value"],
        "dense_h_to_4h": ["dense_h_to_4h"],
        "merged_proj": ["gate_proj", "dense_h_to_4h"],
    }

    def get_mm_mapping(self) -> MultiModelKeys:
        """
        Get the module prefix in multimodal models
        """
        return MultiModelKeys.from_string_field(
            language_model="transformer.encoder",
            connector="transformer.vision.linear_proj",
            tower_model="transformer.vision.transformer",
        )

    @classmethod
    def get_placeholder_str(cls, modality: str, i: int) -> str | None:
        if modality.startswith("image"):
            return "<|begin_of_image|><|endoftext|><|end_of_image|>"

        raise ValueError("Only image modality is supported")

    def __init__(
        self,
        *,
        vllm_config: VllmConfig,
        prefix: str = "",
        transformer_type: type[GLM4VModel] = GLM4VModel,
    ) -> None:
        with self._mark_composite_model(
            vllm_config,
            language_targets=GLMTransformer,
            tower_targets={"image": EVA2CLIPModel},
        ):
            super().__init__(
                vllm_config=vllm_config,
                prefix=prefix,
                transformer_type=transformer_type,
            )

        self.transformer: GLM4VModel

    def _parse_and_validate_image_input(
        self, **kwargs: object
    ) -> GLMVImagePixelInputs | None:
        pixel_values = kwargs.pop("pixel_values", None)

        if pixel_values is not None:
            expected_h = expected_w = self.config.vision_config["image_size"]
            return GLMVImagePixelInputs(
                type="pixel_values",
                data=pixel_values,
                resolve_bindings={"h": expected_h, "w": expected_w},
            )

        return None

    def _process_image_input(self, image_input: GLMVImagePixelInputs) -> torch.Tensor:
        pixel_values = image_input["data"].to(dtype=self.config.dtype)

        return self.transformer.vision(pixel_values)

    def iter_mm_grid_thw(
        self, mm_features: list[MultiModalFeatureSpec]
    ) -> Iterator[tuple[int, int, int, int]]:
        hf_config = self.config
        spatial_merge_size = hf_config.vision_config.spatial_merge_size
        for mm_feature in sorted(mm_features, key=lambda f: f.mm_position.offset):
            offset = mm_feature.mm_position.offset
            if mm_feature.modality == "image":
                t, h, w = mm_feature.data["image_grid_thw"].data.tolist()
                assert t == 1, f"Image must have 1 frame, got {t}"
                yield offset, t, h // spatial_merge_size, w // spatial_merge_size
            else:
                # glm4v only supports image modality
                raise ValueError(f"Unsupported modality: {mm_feature.modality}")

    def get_mrope_input_positions(
        self,
        input_tokens: list[int],
        mm_features: list[MultiModalFeatureSpec],
    ) -> tuple[torch.Tensor, int]:
        llm_pos_ids_list: list = []
        st = 0
        for (
            offset,
            llm_grid_t,
            llm_grid_h,
            llm_grid_w,
        ) in self.iter_mm_grid_thw(mm_features):
            text_len = offset - st
            st_idx = llm_pos_ids_list[-1].max() + 1 if len(llm_pos_ids_list) > 0 else 0
            llm_pos_ids_list.append(
                np.broadcast_to(np.arange(text_len), (3, text_len)) + st_idx
            )
            grid_indices = np.indices((llm_grid_t, llm_grid_h, llm_grid_w)).reshape(
                3, -1
            )
            llm_pos_ids_list.append(grid_indices + text_len + st_idx)
            # EVA2CLIPModel has embeddings for boi and eoi tokens as well
            st = offset + 1 + llm_grid_t * llm_grid_h * llm_grid_w + 1

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

        llm_positions = np.concatenate(llm_pos_ids_list, axis=1).reshape(3, -1)
        mrope_position_delta = (llm_positions.max() + 1 - len(input_tokens)).item()
        return torch.from_numpy(llm_positions), mrope_position_delta

    embed_input_ids = SupportsMultiModal.embed_input_ids

    def embed_multimodal(self, **kwargs: object) -> MultiModalEmbeddings:
        image_input = self._parse_and_validate_image_input(**kwargs)
        if image_input is None:
            return []

        vision_embeddings = self._process_image_input(image_input)
        return vision_embeddings

    def forward(
        self,
        input_ids: torch.Tensor | None,
        positions: torch.Tensor,
        intermediate_tensors: IntermediateTensors | None = None,
        inputs_embeds: torch.Tensor | None = None,
        **kwargs: object,
    ) -> torch.Tensor | IntermediateTensors:
        if intermediate_tensors is not None:
            inputs_embeds = None

        hidden_states = self.transformer(
            input_ids, positions, intermediate_tensors, inputs_embeds
        )

        return hidden_states
