from typing import Literal, List
from fastapi import FastAPI
from fastapi import APIRouter, Depends, HTTPException, Request, UploadFile, Response
from pydantic import BaseModel

from private_gpt.server.ingest.ingest_service import IngestService
from private_gpt.server.ingest.model import IngestedDoc
from private_gpt.server.utils.authentication import get_current_user
ingest_router = APIRouter(prefix="/v1", dependencies=[Depends(get_current_user)])

from fastapi import APIRouter, File, UploadFile, HTTPException, Depends
from fastapi.requests import Request

class IngestResponse(BaseModel):
    object: Literal["list"]
    model: Literal["private-gpt"]
    data: list[IngestedDoc]



@ingest_router.post("/ingest", tags=["Ingestion"])
def ingest(request: Request, files: List[UploadFile]) -> IngestResponse:
    """Ingests and processes files, storing their chunks to be used as context."""

    # Check total file count (including existing files)
    service = request.state.injector.get(IngestService)

    existing_documents = service.list_ingested_filenames()

    if len(existing_documents) + len(files) > 5:
        raise HTTPException(403, "File limit reached. Maximum 5 files allowed.")

    # Limit on number of files:
    if len(files) > 5:
        raise HTTPException(400, "File limit reached (maximum 5 files allowed)")

    # Limit on file extensions:
    allowed_extensions = {"pdf", "csv"}
    for file in files:
        if file.filename.lower().split(".")[-1] not in allowed_extensions:
            raise HTTPException(400, "Invalid file type. Please upload PDF or CSV files only.")

    service = request.state.injector.get(IngestService)
    ingested_documents = []
    for file in files:
        if file.filename is None:
            raise HTTPException(400, "No file name provided")
        ingested_documents.extend(service.ingest_bin_data(file.filename, file.file))

    return IngestResponse(object="list", model="private-gpt", data=ingested_documents)


@ingest_router.get("/ingest/list", tags=["Ingestion"])
def list_ingested(request: Request) -> IngestResponse:
    """Lists already ingested Documents including their Document ID and metadata.

    Those IDs can be used to filter the context used to create responses
    in `/chat/completions`, `/completions`, and `/chunks` APIs.
    """
    service = request.state.injector.get(IngestService)
    ingested_documents = service.list_ingested()
    return IngestResponse(object="list", model="private-gpt", data=ingested_documents)


@ingest_router.delete("/ingest", tags=["Ingestion"])
def delete_ingested(request: Request, file_names: List[str]) -> None:
    """Deletes ingested Documents with the specified file names.

    Accepts a list of file names in the request body and deletes
    all documents associated with those file names.
    """

    service = request.state.injector.get(IngestService)

    # Find documents to delete for each file name
    documents_to_delete = []
    for file_name in file_names:
        ingested_documents = service.list_ingested()
        docs_for_file = [doc.doc_id for doc in ingested_documents if doc.doc_metadata.get("file_name") == file_name]
        documents_to_delete.extend(docs_for_file)

    # Delete the documents
    for doc_id_to_delete in documents_to_delete:
        service.delete(doc_id_to_delete)

    return Response(status_code=204)  # No content



@ingest_router.get("/ingest/list_filenames", tags=["Ingestion"], response_model=List[str])
def list_ingested(request: Request) -> List[str]:
    """Lists already ingested Documents including their Document ID and metadata.

    Those IDs can be used to filter the context used to create responses
    in `/chat/completions`, `/completions`, and `/chunks` APIs.
    """
    service = request.state.injector.get(IngestService)
    ingested_documents: List[IngestedDoc] = service.list_ingested()

    # Extract unique filenames
    unique_filenames = set(doc.doc_metadata.get("file_name", "") for doc in ingested_documents)
    unique_filenames_list = list(unique_filenames)

    return unique_filenames_list