"""Local backup/restore. Run from backend/: python tests/test_local_backup.py"""
from __future__ import annotations

import json
import os
import sqlite3
import sys
import tempfile
import zipfile
from pathlib import Path

ROOT = Path(__file__).resolve().parents[1]
sys.path.insert(0, str(ROOT))

from local_backup import BackupError, create_backup, restore_backup, verify_archive


def expect(ok: bool, message: str) -> None:
    if not ok:
        raise SystemExit(f"FAIL: {message}")
    print(f"OK  {message}")


def write_db(path: Path, value: str) -> None:
    conn = sqlite3.connect(path)
    conn.execute("CREATE TABLE IF NOT EXISTS note (id INTEGER PRIMARY KEY, body TEXT)")
    conn.execute("DELETE FROM note")
    conn.execute("INSERT INTO note (body) VALUES (?)", (value,))
    conn.commit()
    conn.close()


def read_db(path: Path) -> str:
    conn = sqlite3.connect(path)
    row = conn.execute("SELECT body FROM note").fetchone()
    conn.close()
    return row[0] if row else ""


def main() -> None:
    with tempfile.TemporaryDirectory(prefix="kansho-backup-test-") as raw:
        base = Path(raw)
        db = base / "live" / "kansho.sqlite"
        media = base / "live" / "media"
        out = base / "archives"
        db.parent.mkdir(parents=True)
        media.mkdir(parents=True)
        write_db(db, "original-body")
        sample = media / "profile" / "shot.png"
        sample.parent.mkdir(parents=True)
        sample.write_bytes(b"png-bytes")
        secret = base / "live" / ".env"
        secret.write_text("KANSHO_PROVIDER_KEY=sk-secret\n", encoding="utf-8")

        archive = out / "first.zip"
        created = create_backup(archive, db_path=db, media_root=media)
        expect(archive.is_file(), "backup file created")
        expect(created["manifest"]["kind"] == "kansho.local_backup", "manifest kind")
        expect("persönliche, unverschlüsselte" in created["manifest"]["warning"].lower() or "unverschl" in created["manifest"]["warning"], "personal-data warning")
        verified = verify_archive(archive)
        expect(verified["manifest"]["checksums"]["kansho.sqlite"], "sqlite checksum present")
        with zipfile.ZipFile(archive) as zf:
            names = zf.namelist()
            expect("kansho.sqlite" in names, "sqlite in archive")
            expect("media/profile/shot.png" in names, "media in archive")
            expect(".env" not in names, ".env excluded")
            expect(all("sk-secret" not in zf.read(name).decode("latin1", errors="ignore") for name in names if name.endswith(".json") or name.endswith(".txt")), "no secret in manifest/readme")

        try:
            restore_backup(archive, db_path=db, media_root=media, confirm=False)
            expect(False, "restore without confirm must fail")
        except BackupError as exc:
            expect(exc.code == "confirm_required", "restore requires explicit confirm")

        try:
            restore_backup(archive, db_path=db, media_root=media, confirm=True, allow_overwrite=False)
            expect(False, "restore must not silently overwrite")
        except BackupError as exc:
            expect(exc.code == "would_overwrite", "restore refuses existing data without replace")

        target_db = base / "restore" / "kansho.sqlite"
        target_media = base / "restore" / "media"
        restored = restore_backup(
            archive,
            db_path=target_db,
            media_root=target_media,
            confirm=True,
            allow_overwrite=False,
            safety_dir=out,
        )
        expect(read_db(target_db) == "original-body", "restored sqlite content")
        expect((target_media / "profile" / "shot.png").read_bytes() == b"png-bytes", "restored media")
        expect(restored["safety_backup"] is None, "empty target needs no safety backup")

        write_db(target_db, "changed-live")
        (target_media / "profile" / "extra.bin").write_bytes(b"extra")
        replaced = restore_backup(
            archive,
            db_path=target_db,
            media_root=target_media,
            confirm=True,
            allow_overwrite=True,
            safety_dir=out,
        )
        expect(read_db(target_db) == "original-body", "replace restores snapshot")
        expect(not (target_media / "profile" / "extra.bin").exists(), "extra live media not kept")
        expect(Path(replaced["safety_backup"]).is_file(), "safety backup written before replace")
        safety = verify_archive(Path(replaced["safety_backup"]))
        expect(safety["manifest"]["kind"] == "kansho.local_backup", "safety backup is a real archive")

        broken = out / "broken.zip"
        with zipfile.ZipFile(archive) as src, zipfile.ZipFile(broken, "w") as dest:
            for info in src.infolist():
                data = src.read(info.filename)
                if info.filename == "kansho.sqlite":
                    data = data + b"tamper"
                dest.writestr(info, data)
        before = read_db(target_db)
        try:
            restore_backup(broken, db_path=target_db, media_root=target_media, confirm=True, allow_overwrite=True)
            expect(False, "tampered archive must fail")
        except BackupError as exc:
            expect(exc.code == "checksum_mismatch", "tamper detected before restore")
        expect(read_db(target_db) == before, "failed restore leaves current db")

        extra_zip = out / "extra.zip"
        with zipfile.ZipFile(archive) as src, zipfile.ZipFile(extra_zip, "w") as dest:
            for info in src.infolist():
                dest.writestr(info, src.read(info.filename))
            dest.writestr("notes.txt", "not in manifest")
        extra_verified = verify_archive(extra_zip)
        expect("notes.txt" in extra_verified["skipped_extra"], "extra archive files are skipped deterministically")

        locked_db = base / "locked" / "kansho.sqlite"
        locked_media = base / "locked" / "media"
        locked_db.parent.mkdir()
        locked_media.mkdir()
        write_db(locked_db, "locked")
        holder = sqlite3.connect(str(locked_db), timeout=1)
        holder.execute("BEGIN EXCLUSIVE")
        try:
            restore_backup(
                archive,
                db_path=locked_db,
                media_root=locked_media,
                confirm=True,
                allow_overwrite=True,
                safety_dir=out,
            )
            expect(False, "in-use db must abort")
        except BackupError as exc:
            expect(exc.code in {"db_in_use", "db_unavailable", "backup_exists", "would_overwrite"} or "in_use" in exc.code or "unavailable" in exc.code, f"busy db fail-closed ({exc.code})")
        finally:
            holder.rollback()
            holder.close()

    expect(True, "backup tests used only temporary directories")


if __name__ == "__main__":
    main()