"""Backup/restore endpoints for PersistentLearningStore and state data."""

from __future__ import annotations

import json
import shutil
from datetime import datetime, timezone
from pathlib import Path
from typing import Any

from fastapi import APIRouter
from fastapi.responses import FileResponse

from fusionagi._logger import logger

router = APIRouter()

BACKUP_DIR = Path("backups")


@router.post("/backup")
def create_backup(body: dict[str, Any] | None = None) -> dict[str, Any]:
    """Create a backup of learning data and state."""
    BACKUP_DIR.mkdir(parents=True, exist_ok=True)
    timestamp = datetime.now(timezone.utc).strftime("%Y%m%d_%H%M%S")
    backup_id = f"backup_{timestamp}"
    backup_path = BACKUP_DIR / backup_id

    backup_path.mkdir(parents=True, exist_ok=True)

    # Backup PersistentLearningStore
    learning_store_path = Path("data/learning_store.json")
    if learning_store_path.exists():
        shutil.copy2(learning_store_path, backup_path / "learning_store.json")

    # Backup state files
    state_path = Path("data/state.json")
    if state_path.exists():
        shutil.copy2(state_path, backup_path / "state.json")

    # Write manifest
    manifest = {
        "backup_id": backup_id,
        "timestamp": datetime.now(timezone.utc).isoformat(),
        "files": [f.name for f in backup_path.iterdir() if f.is_file()],
    }
    (backup_path / "manifest.json").write_text(json.dumps(manifest, indent=2))

    logger.info("Backup created", extra={"backup_id": backup_id, "path": str(backup_path)})
    return manifest


@router.get("/backups")
def list_backups() -> dict[str, Any]:
    """List available backups."""
    if not BACKUP_DIR.exists():
        return {"backups": []}

    backups = []
    for d in sorted(BACKUP_DIR.iterdir(), reverse=True):
        if d.is_dir():
            manifest_path = d / "manifest.json"
            if manifest_path.exists():
                manifest = json.loads(manifest_path.read_text())
                backups.append(manifest)
            else:
                backups.append({"backup_id": d.name, "files": []})
    return {"backups": backups}


@router.post("/restore/{backup_id}")
def restore_backup(backup_id: str) -> dict[str, Any]:
    """Restore data from a backup."""
    backup_path = BACKUP_DIR / backup_id
    if not backup_path.exists():
        return {"error": f"Backup not found: {backup_id}"}

    data_dir = Path("data")
    data_dir.mkdir(parents=True, exist_ok=True)

    restored = []
    for f in backup_path.iterdir():
        if f.is_file() and f.name != "manifest.json":
            shutil.copy2(f, data_dir / f.name)
            restored.append(f.name)

    logger.info("Backup restored", extra={"backup_id": backup_id, "files": restored})
    return {"backup_id": backup_id, "restored_files": restored, "status": "ok"}


@router.get("/backup/{backup_id}/download")
def download_backup(backup_id: str) -> Any:
    """Download a backup as a zip archive."""
    backup_path = BACKUP_DIR / backup_id
    if not backup_path.exists():
        return {"error": f"Backup not found: {backup_id}"}

    zip_path = BACKUP_DIR / f"{backup_id}.zip"
    shutil.make_archive(str(zip_path.with_suffix("")), "zip", str(backup_path))
    return FileResponse(str(zip_path), media_type="application/zip", filename=f"{backup_id}.zip")