from __future__ import annotations

import hashlib
from pathlib import Path
from uuid import uuid4

from fastapi import UploadFile

from app.common.config.settings import get_settings


settings = get_settings()


class LocalStorageService:
    def __init__(self) -> None:
        self.root = settings.storage_root
        self.root.mkdir(parents=True, exist_ok=True)

    def build_public_url(self, storage_key: str) -> str:
        base = settings.storage_public_base_url.rstrip("/")
        normalized_key = storage_key.replace("\\", "/")
        return f"{base}/{normalized_key}"

    def save_upload(self, upload: UploadFile, *, folder: str) -> dict:
        ext = Path(upload.filename or "file.bin").suffix
        storage_key = f"{folder}/{uuid4().hex}{ext}"
        path = self.root / storage_key
        path.parent.mkdir(parents=True, exist_ok=True)
        content = upload.file.read()
        path.write_bytes(content)
        return {
            "storage_key": storage_key,
            "file_size": len(content),
            "sha256": hashlib.sha256(content).hexdigest(),
            "public_url": self.build_public_url(storage_key),
        }

    def save_bytes(self, content: bytes, *, filename: str, folder: str) -> dict:
        ext = Path(filename).suffix or ".bin"
        storage_key = f"{folder}/{uuid4().hex}{ext}"
        path = self.root / storage_key
        path.parent.mkdir(parents=True, exist_ok=True)
        path.write_bytes(content)
        return {
            "storage_key": storage_key,
            "file_size": len(content),
            "sha256": hashlib.sha256(content).hexdigest(),
            "public_url": self.build_public_url(storage_key),
        }


storage_service = LocalStorageService()