from datetime import datetime
from pathlib import Path
from typing import Awaitable, Callable

from fastapi import FastAPI, Request, Response
from fastapi.responses import FileResponse, JSONResponse
from pydantic import DirectoryPath, FilePath
from pydantic_settings import BaseSettings


class Settings(BaseSettings):
    deck_json_file: FilePath = Path("../state/deck.json")
    scrape_dir: DirectoryPath = Path("../state/scrape")
    snapshots_dir: DirectoryPath = Path("../state/snapshots")


settings = Settings()
app = FastAPI()


@app.middleware("http")
async def cache_control_middleware(
    request: Request, call_next: Callable[[Request], Awaitable[Response]]
) -> Response:
    response = await call_next(request)
    response.headers["Cache-Control"] = "no-cache"
    return response


@app.get("/api/deck")
def get_deck() -> Response:
    return FileResponse(settings.deck_json_file, media_type="application/json")


@app.get("/api/scrapes/{scrape_id}/thumb")
def get_scrape_thumb(scrape_id: str) -> Response:
    image_path = settings.scrape_dir / scrape_id / "derived" / "thumb.png"
    return FileResponse(image_path, media_type="image/png")


@app.get("/api/scrapes/{scrape_id}/tiles/{tile_index}")
def get_scrape_tile(scrape_id: str, tile_index: int) -> Response:
    image_path = (
        settings.scrape_dir / scrape_id / "derived" / "tiles" / f"{tile_index}.png"
    )
    return FileResponse(image_path, media_type="image/png")


@app.get("/api/snapshots")
def list_snapshots() -> Response:
    snapshots: list[str] = []
    for snapshot_path in settings.snapshots_dir.iterdir():
        if snapshot_path.name.endswith(".json"):
            snapshot_id = snapshot_path.name.removesuffix(".json")
            snapshots.append(snapshot_id)
    snapshots.sort(reverse=True)
    return JSONResponse({"snapshots": snapshots})


@app.post("/api/snapshots")
async def post_snapshot(request: Request) -> JSONResponse:
    snapshot_id = datetime.now().strftime("%Y%m%dT%H%M%S")
    with open(settings.snapshots_dir / f"{snapshot_id}.json", "wb") as fh:
        fh.write(await request.body())
    return JSONResponse({"id": snapshot_id})


@app.get("/api/snapshots/{snapshot_id}")
def get_snapshot(snapshot_id: str) -> Response:
    snapshot_file = settings.snapshots_dir / f"{snapshot_id}.json"
    return FileResponse(snapshot_file, media_type="application/json")