"""
Router "file" provides:

- listing files
- finding files by name prefix
- getting files by name prefix
"""

import re
from io import BytesIO
from logging import getLogger
from typing import Iterator

from fastapi import APIRouter, Depends
from fastapi.responses import StreamingResponse
from magic import Magic

from ...dav_common import webdav_ensure_files, webdav_ensure_path
from ...dav_file import DavFile
from ._common import FileNameLister, PrefixFinder, PrefixUnique

_logger = getLogger(__name__)
_magic = Magic(mime=True)

router = APIRouter(prefix="/file", tags=["file"])

file_lister = FileNameLister(
    path_name="file_dir",
    re=re.compile(
        r"[^/]$",
        flags=re.IGNORECASE,
    ),
)

file_finder = PrefixFinder(file_lister)
file_unique = PrefixUnique(file_finder)


@router.on_event("startup")
async def start_router() -> None:
    _logger.debug(f"{router.prefix} router starting.")

    if not webdav_ensure_path(await file_lister.remote_path):
        webdav_ensure_files(
            await file_lister.remote_path,
            "logo.svg",
        )


@router.get(
    "/list",
    response_model=list[str],
    responses=file_lister.responses,
)
async def list_files(
    names: Iterator[str] = Depends(file_lister),
) -> list[str]:
    return list(names)


@router.get(
    "/find/{prefix}",
    response_model=list[str],
    responses=file_finder.responses,
)
async def find_files(
    names: Iterator[str] = Depends(file_finder),
) -> list[str]:
    return list(names)


@router.get(
    "/get/{prefix}",
    response_class=StreamingResponse,
    responses=file_unique.responses,
)
async def get_file(
    prefix: str,
    name: str = Depends(file_unique),
) -> StreamingResponse:
    dav_file = DavFile(f"{await file_lister.remote_path}/{name}")
    buffer = BytesIO(await dav_file.as_bytes)

    mime = _magic.from_buffer(buffer.read(2048))
    buffer.seek(0)

    return StreamingResponse(
        content=buffer,
        media_type=mime,
        headers={
            "Content-Disposition": f"filename={prefix}"
        },
    )