import Foundation
import IndieBackup

/// Backup configuration for IndieBackup (files-only).
///
/// IndieBackup backs up the entire iCloud container `Documents` folder
/// (`backupRoot`, the package default) — exactly where the source of truth
/// lives (`Records/`, `Stubs/`). The SwiftData cache is rebuildable and not
/// part of the backup; it's regenerated from the restored files via
/// `rebuildCacheAfterRestore`.
struct NotesBackupConfiguration: BackupConfiguration {
    /// The sync engine whose observers are suspended during restore and whose
    /// cache is rebuilt afterwards.
    let syncEngine: SyncEngine

    var backupFileExtension: String { "notesbackup" }
    var backupDisplayName: String { "Notes Backup" }

    /// Suspend the metadata observers for the whole restore so the bulk file
    /// replacement isn't processed as a flood of live sync events.
    func prepareForRestore() async {
        await syncEngine.suspendForRestore()
    }

    /// Restart fresh observers once the restored files have settled — a new
    /// NSMetadataQuery re-baselines on gather, so nothing replays.
    func finishRestore() async {
        await syncEngine.resumeAfterRestore()
    }

    /// Rebuild the SwiftData cache so it exactly mirrors the restored files.
    func rebuildCacheAfterRestore(progress: @escaping (Double, String) -> Void) async throws {
        progress(0.0, "Rebuilding notes…")
        await syncEngine.rebuildCache()
        progress(1.0, "Rebuilt")
    }
}