from __future__ import annotations

import json
import os
import shutil
import uuid
from dataclasses import dataclass
from pathlib import Path
from typing import Any


BACKEND_DIR = Path(__file__).resolve().parent
DEFAULT_DATA_ROOT = BACKEND_DIR / "data"


@dataclass(frozen=True)
class DataPaths:
    data_root: Path
    playground_dir: Path
    playground_ref_dir: Path
    playground_metadata_file: Path
    playground_speakers_file: Path
    audio_root: Path
    video_root: Path
    post_root: Path


def get_data_paths() -> DataPaths:
    configured_root = os.getenv("OMNIVOICE_DATA_ROOT", "").strip()
    data_root = Path(configured_root).resolve() if configured_root else DEFAULT_DATA_ROOT
    paths = DataPaths(
        data_root=data_root,
        playground_dir=data_root / "playground",
        playground_ref_dir=data_root / "playground" / "ref",
        playground_metadata_file=data_root / "playground" / "metadata.json",
        playground_speakers_file=data_root / "playground" / "speakers.json",
        audio_root=data_root / "audio",
        video_root=data_root / "video",
        post_root=data_root / "post",
    )
    ensure_paths(paths)
    return paths


def ensure_paths(paths: DataPaths) -> None:
    paths.playground_ref_dir.mkdir(parents=True, exist_ok=True)
    paths.audio_root.mkdir(parents=True, exist_ok=True)
    paths.video_root.mkdir(parents=True, exist_ok=True)
    paths.post_root.mkdir(parents=True, exist_ok=True)


def make_id(prefix: str) -> str:
    return f"{prefix}_{uuid.uuid4().hex[:10]}"


def read_json_file(path: Path, default: Any) -> Any:
    if not path.exists():
        return default
    try:
        return json.loads(path.read_text(encoding="utf-8"))
    except Exception:
        return default


def write_json_file(path: Path, payload: Any) -> None:
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(
        json.dumps(payload, ensure_ascii=False, indent=2),
        encoding="utf-8",
    )


def reset_directory(path: Path) -> None:
    if path.exists():
        shutil.rmtree(path)
    path.mkdir(parents=True, exist_ok=True)