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
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 = {},
):
    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,
                    },
                }
            ),
        )

        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,
                )
            else:
                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)):
    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 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,
        )