using System.Diagnostics;
using System.Runtime.InteropServices;
using WinForms = System.Windows.Forms;

namespace Zcbot.WindowsNode;

internal sealed class TrayHost : IDisposable
{
    private readonly NodeApplicationController controller;
    private readonly MainWindow window;
    private readonly Action shutdown;
    private readonly WinForms.NotifyIcon tray;
    private readonly WinForms.ToolStripMenuItem statusItem;
    private readonly WinForms.ToolStripMenuItem exitItem;
    private NodeStatus current = NodeStatus.Create(NodeState.NotRegistered, "尚未注册");
    private bool exiting;
    private bool disposed;

    internal TrayHost(
        NodeApplicationController controller,
        MainWindow window,
        Action shutdown)
    {
        this.controller = controller;
        this.window = window;
        this.shutdown = shutdown;

        statusItem = new WinForms.ToolStripMenuItem("尚未注册") { Enabled = false };
        exitItem = new WinForms.ToolStripMenuItem("退出节点");
        exitItem.Click += async (_, _) => await ExitNodeAsync();
        var menu = new WinForms.ContextMenuStrip();
        menu.Items.Add(statusItem);
        menu.Items.Add(new WinForms.ToolStripSeparator());
        menu.Items.Add("打开主窗口", null, (_, _) => ShowMainWindow());
        menu.Items.Add("立即重连", null, (_, _) => RestartConnection());
        menu.Items.Add(new WinForms.ToolStripSeparator());
        menu.Items.Add(exitItem);

        tray = new WinForms.NotifyIcon
        {
            ContextMenuStrip = menu,
            Icon = TrayIconFactory.Create(NodeState.NotRegistered),
            Text = "zcbot Windows Node - 尚未注册",
            Visible = true,
        };
        tray.DoubleClick += (_, _) => ShowMainWindow();

        window.ViewModel.CopyDiagnosticsRequested += CopyDiagnostics;
        window.ViewModel.HideRequested += window.Hide;
        window.ViewModel.ExitRequested += ExitNodeAsync;
        window.ViewModel.RegisterRequested += RegisterFromWpfAsync;
        window.ViewModel.ReconnectRequested += ReconnectFromWpfAsync;
        window.ViewModel.ResetIdentityRequested += ResetIdentityFromWpfAsync;
        window.ViewModel.SoftwarePage.ChooseLocationRequested += ChooseSoftwareLocation;
        window.ViewModel.SoftwarePage.ConfirmInstallRequested += ConfirmRuntimeInstall;
        window.ViewModel.AcceptancePage.ChooseReportDirectoryRequested +=
            ChooseAcceptanceReportDirectory;
        window.ViewModel.AcceptancePage.ConfirmRunRequested += ConfirmAnsysAcceptance;
        window.ViewModel.AcceptancePage.ConfirmEnableGateRequested += ConfirmEnableAnsysGate;
        window.ViewModel.DataRootPage.ChooseTargetRequested += ChooseDataRootTarget;
        window.ViewModel.DataRootPage.ConfirmMigrationRequested += ConfirmDataRootMigration;
        window.ViewModel.DataRootPage.MigrationRequested += MigrateDataRootFromWpfAsync;
        window.ViewModel.DataRootPage.MigrationCompleted += CompleteDataRootMigration;
        window.ViewModel.DataRootPage.OpenRequested += OpenDataRoot;
        controller.StatusChanged += PostStatus;
    }

    internal void Start()
    {
        controller.Start();
        UpdateStatus(controller.CurrentStatus);
        if (current.State is NodeState.NotRegistered or NodeState.AuthenticationRequired)
        {
            ShowMainWindow();
        }
    }

    public void Dispose()
    {
        if (disposed) return;
        disposed = true;
        controller.StatusChanged -= PostStatus;
        window.ViewModel.CopyDiagnosticsRequested -= CopyDiagnostics;
        window.ViewModel.HideRequested -= window.Hide;
        window.ViewModel.ExitRequested -= ExitNodeAsync;
        window.ViewModel.RegisterRequested -= RegisterFromWpfAsync;
        window.ViewModel.ReconnectRequested -= ReconnectFromWpfAsync;
        window.ViewModel.ResetIdentityRequested -= ResetIdentityFromWpfAsync;
        window.ViewModel.SoftwarePage.ChooseLocationRequested -= ChooseSoftwareLocation;
        window.ViewModel.SoftwarePage.ConfirmInstallRequested -= ConfirmRuntimeInstall;
        window.ViewModel.AcceptancePage.ChooseReportDirectoryRequested -=
            ChooseAcceptanceReportDirectory;
        window.ViewModel.AcceptancePage.ConfirmRunRequested -= ConfirmAnsysAcceptance;
        window.ViewModel.AcceptancePage.ConfirmEnableGateRequested -= ConfirmEnableAnsysGate;
        window.ViewModel.DataRootPage.ChooseTargetRequested -= ChooseDataRootTarget;
        window.ViewModel.DataRootPage.ConfirmMigrationRequested -= ConfirmDataRootMigration;
        window.ViewModel.DataRootPage.MigrationRequested -= MigrateDataRootFromWpfAsync;
        window.ViewModel.DataRootPage.MigrationCompleted -= CompleteDataRootMigration;
        window.ViewModel.DataRootPage.OpenRequested -= OpenDataRoot;
        window.ViewModel.Dispose();
        controller.Dispose();
        tray.Visible = false;
        tray.Icon?.Dispose();
        tray.Dispose();
    }

    private void PostStatus(NodeStatus status)
    {
        if (window.Dispatcher.CheckAccess())
        {
            UpdateStatus(status);
        }
        else
        {
            _ = window.Dispatcher.InvokeAsync(() => UpdateStatus(status));
        }
    }

    private void UpdateStatus(NodeStatus status)
    {
        current = status;
        window.ViewModel.ApplyStatus(status, controller.CurrentConfig);
        statusItem.Text = CompactMenuText(status.Message, 24);
        tray.Text = Limit($"zcbot Windows Node - {status.Message}", 63);
        var oldIcon = tray.Icon;
        tray.Icon = TrayIconFactory.Create(status.State);
        oldIcon?.Dispose();
    }

    private void ShowMainWindow() => window.ShowAndActivate();

    private async void RestartConnection()
    {
        if (!await controller.ReconnectAsync())
        {
            ShowMainWindow();
        }
    }

    private static bool CopyDiagnostics(string text)
    {
        try
        {
            WinForms.Clipboard.SetText(text);
            return true;
        }
        catch (ExternalException)
        {
            return false;
        }
    }

    private Task RegisterFromWpfAsync(EnrollOptions options) =>
        controller.RegisterAsync(options);

    private Task<bool> ReconnectFromWpfAsync() => controller.ReconnectAsync();

    private async Task<bool> ResetIdentityFromWpfAsync()
    {
        if (WinForms.MessageBox.Show(
                "这会删除本机加密身份，随后需要使用新注册码重新注册。请先在管理后台删除或禁用云端旧节点。是否继续？",
                "清除本机节点身份",
                WinForms.MessageBoxButtons.YesNo,
                WinForms.MessageBoxIcon.Warning,
                WinForms.MessageBoxDefaultButton.Button2) != WinForms.DialogResult.Yes)
        {
            return false;
        }

        await controller.ResetIdentityAsync();
        return true;
    }

    private string? ChooseSoftwareLocation(
        SoftwarePathKind pathKind,
        string displayName,
        string requiredRelativePath)
    {
        if (pathKind == SoftwarePathKind.Executable)
        {
            using var dialog = new WinForms.OpenFileDialog
            {
                Title = $"选择 {displayName} 可执行文件",
                Filter = $"{requiredRelativePath}|{requiredRelativePath}|可执行文件 (*.exe)|*.exe",
                CheckFileExists = true,
                Multiselect = false,
            };
            return dialog.ShowDialog() == WinForms.DialogResult.OK
                ? dialog.FileName
                : null;
        }
        if (pathKind == SoftwarePathKind.Directory)
        {
            using var dialog = new WinForms.FolderBrowserDialog
            {
                Description = $"选择 {displayName} 安装根目录",
                UseDescriptionForTitle = true,
                ShowNewFolderButton = false,
            };
            return dialog.ShowDialog() == WinForms.DialogResult.OK
                ? dialog.SelectedPath
                : null;
        }
        return null;
    }

    private static string? ChooseAcceptanceReportDirectory()
    {
        using var dialog = new WinForms.FolderBrowserDialog
        {
            Description = "选择保存 ANSYS 验收报告的父目录",
            UseDescriptionForTitle = true,
            ShowNewFolderButton = true,
        };
        return dialog.ShowDialog() == WinForms.DialogResult.OK
            ? dialog.SelectedPath
            : null;
    }

    private static bool ConfirmAnsysAcceptance() => WinForms.MessageBox.Show(
        "程序会使用内置标准试件执行一次进程树取消和连续 20 次真实静力求解，期间会获取并释放 ANSYS 许可证，可能耗时较长。确认开始？",
        "开始 ANSYS 真机验收",
        WinForms.MessageBoxButtons.YesNo,
        WinForms.MessageBoxIcon.Warning,
        WinForms.MessageBoxDefaultButton.Button2) == WinForms.DialogResult.Yes;

    private static bool ConfirmEnableAnsysGate() => WinForms.MessageBox.Show(
        "请先在许可证管理端确认正常求解和取消后的席位均已释放。开启后需要完全退出并重新启动 Node 才会进入实际调度。确认开启机器级执行门？",
        "开启 ANSYS 执行门",
        WinForms.MessageBoxButtons.YesNo,
        WinForms.MessageBoxIcon.Warning,
        WinForms.MessageBoxDefaultButton.Button2) == WinForms.DialogResult.Yes;

    private static string? ChooseDataRootTarget(string currentRoot)
    {
        using var dialog = new WinForms.FolderBrowserDialog
        {
            Description = "选择新的 zcbot Windows Node 数据目录（必须为空）",
            UseDescriptionForTitle = true,
            SelectedPath = currentRoot,
            ShowNewFolderButton = true,
        };
        return dialog.ShowDialog() == WinForms.DialogResult.OK
            ? dialog.SelectedPath
            : null;
    }

    private Task<NodeDataMigrationResult> MigrateDataRootFromWpfAsync(string target) =>
        controller.MigrateDataRootAsync(target);

    private static bool ConfirmDataRootMigration(string target) =>
        WinForms.MessageBox.Show(
            $"Node 将先停止接收任务，把现有数据复制并校验到：\n{target}\n\n"
            + "校验成功后切换目录并重启；旧目录不会自动删除。是否继续？",
            "迁移数据目录",
            WinForms.MessageBoxButtons.YesNo,
            WinForms.MessageBoxIcon.Warning,
            WinForms.MessageBoxDefaultButton.Button2) == WinForms.DialogResult.Yes;

    private static void CompleteDataRootMigration(NodeDataMigrationResult result)
    {
        WinForms.MessageBox.Show(
            $"数据目录迁移完成：{result.FileCount} 个文件。\n"
            + $"新目录：{result.TargetDirectory}\n\n旧目录仍保留：{result.SourceDirectory}\n"
            + "确认新节点运行正常后，可由管理员手工清理旧目录。Node 现在将重启。",
            "迁移完成",
            WinForms.MessageBoxButtons.OK,
            WinForms.MessageBoxIcon.Information);
        WinForms.Application.Restart();
    }

    private static void OpenDataRoot(string path)
    {
        try
        {
            Directory.CreateDirectory(path);
            var startInfo = new ProcessStartInfo
            {
                FileName = Path.Combine(
                    Environment.GetFolderPath(Environment.SpecialFolder.Windows),
                    "explorer.exe"),
                UseShellExecute = false,
            };
            startInfo.ArgumentList.Add(path);
            Process.Start(startInfo);
        }
        catch (Exception exception) when (
            exception is IOException or UnauthorizedAccessException or InvalidOperationException)
        {
            WinForms.MessageBox.Show(
                exception.Message,
                "无法打开数据目录",
                WinForms.MessageBoxButtons.OK,
                WinForms.MessageBoxIcon.Error);
        }
    }

    private static bool ConfirmRuntimeInstall(string displayName) =>
        WinForms.MessageBox.Show(
            $"将为 {displayName} 创建独立 Python 3.12 运行环境并安装固定依赖。是否继续？",
            "安装专业软件运行环境",
            WinForms.MessageBoxButtons.YesNo,
            WinForms.MessageBoxIcon.Question,
            WinForms.MessageBoxDefaultButton.Button2) == WinForms.DialogResult.Yes;

    private async Task ExitNodeAsync()
    {
        if (exiting) return;

        var activeJobs = controller.ActiveJobCount;
        var cancelJobs = false;
        if (activeJobs > 0)
        {
            var choice = WinForms.MessageBox.Show(
                $"当前有 {activeJobs} 个本机任务尚未结束。\n\n"
                + "选择“是”：停止接收新任务，等待现有任务完成后退出。\n"
                + "选择“否”：取消现有任务并退出。\n"
                + "选择“取消”：返回，不退出。",
                "退出 zcbot Windows Node",
                WinForms.MessageBoxButtons.YesNoCancel,
                WinForms.MessageBoxIcon.Warning,
                WinForms.MessageBoxDefaultButton.Button1);
            if (choice == WinForms.DialogResult.Cancel) return;
            cancelJobs = choice == WinForms.DialogResult.No;
            if (cancelJobs && WinForms.MessageBox.Show(
                    "取消任务会终止正在运行的专业软件进程，未完成结果不会上传。确认取消任务并退出？",
                    "确认取消任务",
                    WinForms.MessageBoxButtons.YesNo,
                    WinForms.MessageBoxIcon.Warning,
                    WinForms.MessageBoxDefaultButton.Button2) != WinForms.DialogResult.Yes)
            {
                return;
            }
        }

        exiting = true;
        window.ViewModel.BeginExit();
        window.IsEnabled = false;
        exitItem.Enabled = false;
        if (tray.ContextMenuStrip is not null) tray.ContextMenuStrip.Enabled = false;
        await controller.StopAsync(
            cancelJobs ? NodeShutdownMode.CancelJobs : NodeShutdownMode.WaitForJobs);
        tray.Visible = false;
        window.AllowClose = true;
        window.Close();
        shutdown();
    }

    private static string Limit(string value, int length) =>
        value.Length <= length ? value : value[..length];

    private static string CompactMenuText(string value, int length)
    {
        var singleLine = value.Replace('\r', ' ').Replace('\n', ' ').Trim();
        return singleLine.Length <= length
            ? singleLine
            : singleLine[..(length - 1)] + "…";
    }
}