import logging
import os
import uuid
from pathlib import Path
from typing import Optional
from urllib.parse import quote

from fastapi import (
    APIRouter,
    Depends,
    File,
    HTTPException,
    Request,
    UploadFile,
    status,
    Query,
)
from fastapi.responses import FileResponse, StreamingResponse
from open_webui.constants import ERROR_MESSAGES
from open_webui.env import SRC_LOG_LEVELS
from open_webui.models.files import (
    FileForm,
    FileModel,
    FileModelResponse,
    Files,
)
from open_webui.routers.knowledge import get_knowledge, get_knowledge_list
from open_webui.routers.retrieval import ProcessFileForm, process_file
from open_webui.routers.audio import transcribe
from open_webui.storage.provider import Storage
from open_webui.utils.auth import get_admin_user, get_verified_user
from pydantic import BaseModel

log = logging.getLogger(__name__)
log.setLevel(SRC_LOG_LEVELS["MODELS"])


router = APIRouter()

############################
# Check if the current user has access to a file through any knowledge bases the user may be in.
############################
async def check_user_has_access_to_file_via_any_knowledge_base(file_id: Optional[str], access_type: str, user=Depends(get_verified_user)) -> bool:
    file = Files.get_file_by_id(file_id)
    log.debug(f"Checking if user has {access_type} access to file")

    if not file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    
    has_access = False
    knowledge_base_id = file.meta.get("collection_name") if file.meta else None
    log.debug(f"Knowledge base associated with file: {knowledge_base_id}")
    if knowledge_base_id:
        if access_type == "read":
            user_access = await get_knowledge(user=user) # get_knowledge checks for read access
        elif access_type == "write":
            user_access = await get_knowledge_list(user=user) # get_knowledge_list checks for write access
        else:
            user_access = list()
        
        for knowledge_base in user_access:
            if knowledge_base.id == knowledge_base_id:
                log.debug(f"User knowledge base with {access_type} access {knowledge_base.id} == File knowledge base {knowledge_base_id}")
                has_access = True
                break

    
    log.debug(f"Does user have {access_type} access to file: {has_access}")

    return has_access
    


############################
# Upload File
############################


@router.post("/", response_model=FileModelResponse)
def upload_file(
    request: Request,
    file: UploadFile = File(...),
    user=Depends(get_verified_user),
    file_metadata: dict = {},
    process: bool = Query(True),
):
    log.info(f"file.content_type: {file.content_type}")
    try:
        unsanitized_filename = file.filename
        filename = os.path.basename(unsanitized_filename)

        # replace filename with uuid
        id = str(uuid.uuid4())
        name = filename
        filename = f"{id}_{filename}"
        contents, file_path = Storage.upload_file(file.file, filename)

        file_item = Files.insert_new_file(
            user.id,
            FileForm(
                **{
                    "id": id,
                    "filename": name,
                    "path": file_path,
                    "meta": {
                        "name": name,
                        "content_type": file.content_type,
                        "size": len(contents),
                        "data": file_metadata,
                    },
                }
            ),
        )
        if process:
            try:
                if file.content_type in [
                    "audio/mpeg",
                    "audio/wav",
                    "audio/ogg",
                    "audio/x-m4a",
                ]:
                    file_path = Storage.get_file(file_path)
                    result = transcribe(request, file_path)
                    process_file(
                        request,
                        ProcessFileForm(file_id=id, content=result.get("text", "")),
                        user=user,
                    )
                elif file.content_type not in ["image/png", "image/jpeg", "image/gif"]:
                    process_file(request, ProcessFileForm(file_id=id), user=user)
                    file_item = Files.get_file_by_id(id=id)
            except Exception as e:
                log.exception(e)
                log.error(f"Error processing file: {file_item.id}")
                file_item = FileModelResponse(
                    **{
                        **file_item.model_dump(),
                        "error": str(e.detail) if hasattr(e, "detail") else str(e),
                    }
                )

        if file_item:
            return file_item
        else:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail=ERROR_MESSAGES.DEFAULT("Error uploading file"),
            )

    except Exception as e:
        log.exception(e)
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.DEFAULT(e),
        )


############################
# List Files
############################


@router.get("/", response_model=list[FileModelResponse])
async def list_files(user=Depends(get_verified_user)):
    if user.role == "admin":
        files = Files.get_files()
    else:
        files = Files.get_files_by_user_id(user.id)
    return files


############################
# Delete All Files
############################


@router.delete("/all")
async def delete_all_files(user=Depends(get_admin_user)):
    result = Files.delete_all_files()
    if result:
        try:
            Storage.delete_all_files()
        except Exception as e:
            log.exception(e)
            log.error("Error deleting files")
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail=ERROR_MESSAGES.DEFAULT("Error deleting files"),
            )
        return {"message": "All files deleted successfully"}
    else:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=ERROR_MESSAGES.DEFAULT("Error deleting files"),
        )


############################
# Get File By Id
############################


@router.get("/{id}", response_model=Optional[FileModel])
async def get_file_by_id(id: str, user=Depends(get_verified_user)):
    file = Files.get_file_by_id(id)

    if not file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    
    has_read_access: bool = await check_user_has_access_to_file_via_any_knowledge_base(id, "read", user)

    if file.user_id == user.id or user.role == "admin" or has_read_access:
        return file
    else:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


############################
# Get File Data Content By Id
############################


@router.get("/{id}/data/content")
async def get_file_data_content_by_id(id: str, user=Depends(get_verified_user)):
    file = Files.get_file_by_id(id)

    if not file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    
    has_read_access: bool = await check_user_has_access_to_file_via_any_knowledge_base(id, "read", user)

    if file.user_id == user.id or user.role == "admin" or has_read_access:
        return {"content": file.data.get("content", "")}
    else:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


############################
# Update File Data Content By Id
############################


class ContentForm(BaseModel):
    content: str


@router.post("/{id}/data/content/update")
async def update_file_data_content_by_id(
    request: Request, id: str, form_data: ContentForm, user=Depends(get_verified_user)
):
    file = Files.get_file_by_id(id)

    if not file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    
    has_write_access: bool = await check_user_has_access_to_file_via_any_knowledge_base(id, "write", user)

    if file.user_id == user.id or user.role == "admin" or has_write_access:
        try:
            process_file(
                request,
                ProcessFileForm(file_id=id, content=form_data.content),
                user=user,
            )
            file = Files.get_file_by_id(id=id)
        except Exception as e:
            log.exception(e)
            log.error(f"Error processing file: {file.id}")

        return {"content": file.data.get("content", "")}
    else:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


############################
# Get File Content By Id
############################


@router.get("/{id}/content")
async def get_file_content_by_id(
    id: str, user=Depends(get_verified_user), attachment: bool = Query(False)
):
    file = Files.get_file_by_id(id)

    if not file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    
    has_read_access: bool = await check_user_has_access_to_file_via_any_knowledge_base(id, "read", user)

    if file.user_id == user.id or user.role == "admin" or has_read_access:
        try:
            file_path = Storage.get_file(file.path)
            file_path = Path(file_path)

            # Check if the file already exists in the cache
            if file_path.is_file():
                # Handle Unicode filenames
                filename = file.meta.get("name", file.filename)
                encoded_filename = quote(filename)  # RFC5987 encoding

                content_type = file.meta.get("content_type")
                filename = file.meta.get("name", file.filename)
                encoded_filename = quote(filename)
                headers = {}

                if attachment:
                    headers["Content-Disposition"] = (
                        f"attachment; filename*=UTF-8''{encoded_filename}"
                    )
                else:
                    if content_type == "application/pdf" or filename.lower().endswith(
                        ".pdf"
                    ):
                        headers["Content-Disposition"] = (
                            f"inline; filename*=UTF-8''{encoded_filename}"
                        )
                        content_type = "application/pdf"
                    elif content_type != "text/plain":
                        headers["Content-Disposition"] = (
                            f"attachment; filename*=UTF-8''{encoded_filename}"
                        )

                return FileResponse(file_path, headers=headers, media_type=content_type)

            else:
                raise HTTPException(
                    status_code=status.HTTP_404_NOT_FOUND,
                    detail=ERROR_MESSAGES.NOT_FOUND,
                )
        except Exception as e:
            log.exception(e)
            log.error("Error getting file content")
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail=ERROR_MESSAGES.DEFAULT("Error getting file content"),
            )
    else:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


@router.get("/{id}/content/html")
async def get_html_file_content_by_id(id: str, user=Depends(get_verified_user)):
    file = Files.get_file_by_id(id)

    if not file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    
    has_read_access: bool = await check_user_has_access_to_file_via_any_knowledge_base(id, "read", user)

    if file.user_id == user.id or user.role == "admin" or has_read_access:
        try:
            file_path = Storage.get_file(file.path)
            file_path = Path(file_path)

            # Check if the file already exists in the cache
            if file_path.is_file():
                log.info(f"file_path: {file_path}")
                return FileResponse(file_path)
            else:
                raise HTTPException(
                    status_code=status.HTTP_404_NOT_FOUND,
                    detail=ERROR_MESSAGES.NOT_FOUND,
                )
        except Exception as e:
            log.exception(e)
            log.error("Error getting file content")
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail=ERROR_MESSAGES.DEFAULT("Error getting file content"),
            )
    else:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


@router.get("/{id}/content/{file_name}")
async def get_file_content_by_id(id: str, user=Depends(get_verified_user)):
    file = Files.get_file_by_id(id)

    if not file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    
    has_read_access: bool = await check_user_has_access_to_file_via_any_knowledge_base(id, "read", user)

    if file.user_id == user.id or user.role == "admin" or has_read_access:
        file_path = file.path

        # Handle Unicode filenames
        filename = file.meta.get("name", file.filename)
        encoded_filename = quote(filename)  # RFC5987 encoding
        headers = {
            "Content-Disposition": f"attachment; filename*=UTF-8''{encoded_filename}"
        }

        if file_path:
            file_path = Storage.get_file(file_path)
            file_path = Path(file_path)

            # Check if the file already exists in the cache
            if file_path.is_file():
                return FileResponse(file_path, headers=headers)
            else:
                raise HTTPException(
                    status_code=status.HTTP_404_NOT_FOUND,
                    detail=ERROR_MESSAGES.NOT_FOUND,
                )
        else:
            # File path doesn’t exist, return the content as .txt if possible
            file_content = file.content.get("content", "")
            file_name = file.filename

            # Create a generator that encodes the file content
            def generator():
                yield file_content.encode("utf-8")

            return StreamingResponse(
                generator(),
                media_type="text/plain",
                headers=headers,
            )
    else:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )


############################
# Delete File By Id
############################


@router.delete("/{id}")
async def delete_file_by_id(id: str, user=Depends(get_verified_user)):
    file = Files.get_file_by_id(id)

    if not file:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )
    
    has_write_access: bool = await check_user_has_access_to_file_via_any_knowledge_base(id, "write", user)

    if file.user_id == user.id or user.role == "admin" or has_write_access:
        # We should add Chroma cleanup here

        result = Files.delete_file_by_id(id)
        if result:
            try:
                Storage.delete_file(file.path)
            except Exception as e:
                log.exception(e)
                log.error("Error deleting files")
                raise HTTPException(
                    status_code=status.HTTP_400_BAD_REQUEST,
                    detail=ERROR_MESSAGES.DEFAULT("Error deleting files"),
                )
            return {"message": "File deleted successfully"}
        else:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail=ERROR_MESSAGES.DEFAULT("Error deleting file"),
            )
    else:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=ERROR_MESSAGES.NOT_FOUND,
        )