namespace FluidExplorer.Navigation;

public enum LocationKind
{
    Home,
    Gallery,
    QuickAccess,
    ThisPc,
    RecycleBin,
    Network,
    Drive,
    Folder,
    Search
}

/// <summary>一个可导航的位置（侧边栏节点、面包屑、标签页都基于它）。</summary>
public sealed record NavigationLocation(LocationKind Kind, string Path, string DisplayName, string Glyph)
{
    public static NavigationLocation Home { get; } = new(LocationKind.Home, Services.Shell.KnownFolders.HomeParsingName, "主页", "\uE80F");
    public static NavigationLocation Gallery { get; } = new(LocationKind.Gallery, Services.Shell.KnownFolders.GalleryParsingName, "图库", "\uE91B");
    public static NavigationLocation ThisPc { get; } = new(LocationKind.ThisPc, Services.Shell.KnownFolders.ThisPcParsingName, "此电脑", "\uE977");
    public static NavigationLocation RecycleBin { get; } = new(LocationKind.RecycleBin, Services.Shell.KnownFolders.RecycleBinParsingName, "回收站", "\uE74D");
    public static NavigationLocation Network { get; } = new(LocationKind.Network, Services.Shell.KnownFolders.NetworkParsingName, "网络", "\uE968");

    public static NavigationLocation FromPath(string path, LocationKind kind = LocationKind.Folder)
    {
        var normalized = Services.FileSystem.PathHelper.NormalizeDisplay(path);
        return new NavigationLocation(kind, normalized, Services.FileSystem.PathHelper.GetName(normalized), "\uE8B7");
    }

    public static NavigationLocation FromDrive(DriveItemInfo drive)
        => new(LocationKind.Drive, drive.RootPath, drive.DisplayName, drive.Glyph);

    /// <summary>是否是外壳虚拟位置（不能用 System.IO 直接枚举，需要走 shell: 视图）。</summary>
    public bool IsVirtual => Kind is LocationKind.Home or LocationKind.Gallery or LocationKind.ThisPc
        or LocationKind.RecycleBin or LocationKind.Network or LocationKind.Search
        || Path.StartsWith("::", StringComparison.Ordinal) || Path.StartsWith("shell:", StringComparison.OrdinalIgnoreCase);
}

public readonly record struct DriveItemInfo(string RootPath, string DisplayName, string Glyph);

/// <summary>前进/后退历史（资源管理器行为：新导航截断前进栈）。</summary>
public sealed class NavigationHistory
{
    private readonly List<NavigationLocation> _back = [];
    private readonly List<NavigationLocation> _forward = [];
    private const int Capacity = 64;

    public bool CanGoBack => _back.Count > 1;
    public bool CanGoForward => _forward.Count > 0;
    public NavigationLocation? Current => _back.Count > 0 ? _back[^1] : null;

    public void Push(NavigationLocation location)
    {
        if (_back.Count > 0 && _back[^1] == location) return;
        _back.Add(location);
        if (_back.Count > Capacity) _back.RemoveAt(0);
        _forward.Clear();
    }

    public NavigationLocation? Back()
    {
        if (!CanGoBack) return null;
        var current = _back[^1];
        _back.RemoveAt(_back.Count - 1);
        _forward.Add(current);
        return _back[^1];
    }

    public NavigationLocation? Forward()
    {
        if (_forward.Count == 0) return null;
        var next = _forward[^1];
        _forward.RemoveAt(_forward.Count - 1);
        _back.Add(next);
        return next;
    }

    public void Reset(NavigationLocation location)
    {
        _back.Clear();
        _forward.Clear();
        _back.Add(location);
    }
}