using System.Collections;

namespace AibisDream.SaveSystem
{
    /// <summary>
    /// 快照层对外 API：Capture / Restore，不涉及文件与 UI。
    /// 游戏逻辑应优先使用 <see cref="SaveRestoreOrchestrator"/> 完成存读档流程。
    /// </summary>
    public static class SnapshotService
    {
        /// <summary>捕获当前运行时快照。</summary>
        public static SaveSnapshot Capture()
        {
            SnapshotRegistry.EnsureInitialized();
            return SnapshotCapture.Capture(YarnVariableStorage.Instance);
        }

        /// <summary>
        /// 还原快照。默认在 provider 还原后继续执行 <see cref="SnapshotRestore.RestoreAnchor"/>。
        /// </summary>
        /// <param name="restoreAnchor">为 false 时仅还原状态，不重进 Yarn 节点（供 P4 编排使用）。</param>
        public static IEnumerator Restore(SaveSnapshot snapshot, bool restoreAnchor = true)
        {
            if (snapshot == null)
            {
                yield break;
            }

            SnapshotRegistry.EnsureInitialized();
            yield return SnapshotRestore.Restore(YarnVariableStorage.Instance, snapshot);

            if (restoreAnchor)
            {
                yield return SnapshotRestore.RestoreAnchor(snapshot);
            }
        }
    }
}