#!/bin/sh
set -eu
umask 077
if [ "${3:-}" != "--confirm-restore" ]; then
  echo 'Refusing restore: pass --confirm-restore explicitly.' >&2
  exit 2
fi
SOURCE=${1:-}
TARGET=${2:-${PROSPECT_API_DB:-${DATA_DIR:-/data}/prospects.db}}
BACKUP_DIR=${BACKUP_DIR:-$(dirname -- "$SOURCE")}
case "$SOURCE$TARGET" in *secret*|*credentials*|*.env*) echo 'refusing secret-like path' >&2; exit 2;; esac
[ -f "$SOURCE" ] || { echo 'restore source does not exist' >&2; exit 2; }
case "$TARGET" in /*) ;; *) echo 'restore target must be an absolute path' >&2; exit 2;; esac
mkdir -p -- "$BACKUP_DIR"
if [ -f "$TARGET" ]; then
  pre_restore=$("$(dirname -- "$0")/backup_sqlite.sh" "$TARGET" "$BACKUP_DIR" 30)
  pre_restore_db=$(printf '%s\n' "$pre_restore" | tail -n 1)
  pre_restore_name="$BACKUP_DIR/pre-restore-$(date -u +%Y%m%dT%H%M%SZ)-$$.db"
  mv -- "$pre_restore_db" "$pre_restore_name"
  if [ -f "$pre_restore_db.sha256" ]; then mv -- "$pre_restore_db.sha256" "$pre_restore_name.sha256"; fi
fi
python3 - "$SOURCE" "$TARGET" <<'PY'
import hashlib, os, sqlite3, sys, tempfile
from pathlib import Path
source, target = Path(sys.argv[1]).resolve(), Path(sys.argv[2]).resolve()
if not source.is_file(): raise SystemExit('restore source must be a regular file')
sidecar = Path(str(source)+'.sha256')
if sidecar.exists():
    expected = sidecar.read_text(encoding='ascii').split()[0]
    actual = hashlib.sha256(source.read_bytes()).hexdigest()
    if expected != actual: raise SystemExit('restore checksum mismatch')
target.parent.mkdir(parents=True, exist_ok=True)
fd, tmp = tempfile.mkstemp(prefix='.restore-', suffix='.tmp', dir=target.parent); os.close(fd)
try:
    with sqlite3.connect(f'file:{source}?mode=ro', uri=True) as src, sqlite3.connect(tmp) as dst:
        src.backup(dst); result = dst.execute('PRAGMA integrity_check').fetchone()[0]
        if result != 'ok': raise SystemExit('restored database integrity check failed')
        dst.commit()
    os.chmod(tmp, 0o600); os.replace(tmp, target)
    print(target)
finally:
    Path(tmp).unlink(missing_ok=True)
PY