from fastapi import FastAPI, File, UploadFile, HTTPException
from fastapi.responses import FileResponse, PlainTextResponse
from sqlalchemy import exists
import hashlib
import db
import os

def compute_hash(data: bytes, algorithm="sha256") -> str:
    h = hashlib.new(algorithm)
    h.update(data)
    return h.hexdigest()

app = FastAPI()

FILES_DIR = "./files"

@app.get("/")
def root():
    return {"message": "hiii from sfs"}

@app.get("/{filename}")
def get_file(filename: str, raw: bool = False):
    file_path = os.path.join(FILES_DIR, filename)

    if not os.path.exists(file_path):
        raise HTTPException(status_code=404, detail="File not found")
    if raw:
        with open(file_path, "r", encoding="utf-8", errors="ignore") as f:
            return PlainTextResponse(f.read())

    return FileResponse(file_path, filename=filename)


@app.post("/")
async def save_file(file: UploadFile = File(...)):
    contents = await file.read()
    
    hash = compute_hash(contents)

    existed_url = db.file_exists(file.size, hash)

    if not existed_url:
        file_url = db.add_file(file.filename, file.content_type, file.size, hash)
    
        print(f"{FILES_DIR}/{file_url}")
        with open(f"{FILES_DIR}/{file_url}", "wb") as f:
            f.write(contents)
        return {"status": "saved", "filename": file_url}
    else:
        return {"status": "file_exists", "filename": existed_url}

@app.get("/healthchecker")
def healthchecker():
    return {"message": "Howdy :3"}