using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using DevExpress.Utils.MVVM;
using DevExpress.Mvvm.POCO;
using DevExpress.Mvvm;
using DevExpress.XtraSplashScreen;
using DevExpress.XtraBars.Alerter;
using DevExpress.XtraBars.ToastNotifications;
using System.Windows.Forms;
using DevExpress.XtraWaitForm;
using System.Threading;
using DevExpress.XtraEditors;
using DevExpress.Utils.MVVM.Services;


/// <summary>
/// <para>ViewModel基类</para>
/// <para>GetService方法不是线程安全的,避免后台线程调用,可使用BeginInvoke切换到UI线程</para>
/// </summary>
public abstract class BaseVm
{
    /// <summary>
    /// 切换到UI线程直接委托
    /// </summary>
    /// <param name="action">UI线程要执行的委托</param>
    public void Invoke(Action action)
    {
        try
        {
            IDispatchService.Invoke(action);
        }
        catch (Exception)
        {
            //退出时这里可能会出错,此时可忽略
        }
    }
    /// <summary>
    /// 切换到UI线程直接委托
    /// </summary>
    /// <param name="action">UI线程要执行的委托</param>
    public async void BeginInvoke(Action action)
    {
        await IDispatchService.BeginInvoke(action);
    }
    /// <summary>
    /// 向其它ViewModel发送数据
    /// </summary>
    /// <typeparam name="T">数据泛型类型,需要和Register中的类型一致</typeparam>
    /// <param name="data">数据</param>
    /// <param name="token">令牌,需要和Register中的令牌一致</param>
    public void Send<T>(T data, string token)
    {
        DevExpress.Mvvm.Messenger.Default.Send(data, token);
    }

    /// <summary>
    /// <para>注册接收其它ViewModel数据的回调</para>
    /// <para>需要注意callback执行线程可能不是UI线程,callback操作绑定对象需要调用Invoke或BeginInvoke</para>
    /// </summary>
    /// <typeparam name="T">数据泛型类型,需要和Send中的类型一致</typeparam>
    /// <param name="callback">数据</param>
    /// <param name="token">令牌,需要和Send中的令牌一致</param>
    public void Register<T>(Action<T> callback, string token)
    {
        DevExpress.Mvvm.Messenger.Default.Register(this, token, callback);
    }
    protected DialogResult DialogResult;
    public void UnRegister()
    {
        DevExpress.Mvvm.Messenger.Default.Unregister(this);
    }
    /// <summary>
    /// 选择目录(取消则返回null)
    /// </summary>
    /// <returns></returns>
    public string DialogChooseDir()
    {
        if (!IFolderService.ShowDialog()) return null;
        return IFolderService.ResultPath;
    }

    /// <summary>
    /// 选择文件(取消则返回null)
    /// </summary>
    /// <param name="filter">such as "文本文件|*.txt"</param>
    /// <param name="multiselect">是否支持多选</param>
    /// <returns></returns>
    public string DialogChooseFile(string filter = "文本文件|*.txt", bool multiselect = false)
    {
        IOpenFileService.Filter = filter;
        IOpenFileService.Multiselect = multiselect;
        if (!IOpenFileService.ShowDialog()) return null;
        return IOpenFileService.GetFullFileName();
    }

    /// <summary>
    /// 保存文件(取消则返回null)
    /// </summary>
    /// <param name="fileName"></param>
    /// <returns></returns>
    public string DialogSaveFile(string fileName)
    {
        if (!ISaveFileService.ShowDialog(null, "", fileName)) return null;
        return ISaveFileService.GetFullFileName();
    }

    /// <summary>
    /// 从右下角弹出通知
    /// </summary>
    /// <param name="msg"></param>
    public void ShowNotify(string msg)
    {
        Invoke(async () =>
        {
            var notify = INotifyService.CreatePredefinedNotification("消息", "\r\n" + " " + msg, null);
            await notify.ShowAsync();
        });
    }

    /// <summary>
    /// 从右下角弹出通知
    /// </summary>
    /// <param name="msg"></param>
    public void ShowNotifyError(string msg)
    {
        Invoke(async () =>
        {
            var notify = INotifyService.CreatePredefinedNotification("错误", "\r\n" + " " + msg, null);
            await notify.ShowAsync();
        });

    }

    /// <summary>
    /// 显示提示消息
    /// </summary>
    /// <param name="msg"></param>
    public void ShowMsg(string msg)
    {
        Invoke(() =>
        {
            IMsgBoxService.ShowMessage(msg, "提示", MessageButton.OK, MessageIcon.Information);

        });
    }

    /// <summary>
    /// 显示警告消息
    /// </summary>
    /// <param name="msg"></param>
    public void ShowWarning(string msg)
    {
        Invoke(() =>
        {
            IMsgBoxService.ShowMessage(msg, "警告", MessageButton.OK, MessageIcon.Warning);
        });
    }

    /// <summary>
    /// 显示错误消息
    /// </summary>
    /// <param name="msg"></param>
    public void ShowError(string msg)
    {
        Invoke(() =>
        {
            IMsgBoxService.ShowMessage(msg, "错误", MessageButton.OK, MessageIcon.Error);
        });

    }

    /// <summary>
    /// 显示确认消息
    /// </summary>
    /// <param name="msg"></param>
    /// <returns></returns>
    public bool ShowConfirm(string msg)
    {
        bool res = false;
        Invoke(() =>
        {
            if (!msg.Contains("?") && !msg.Contains("？")) msg += "?";
            res = IMsgBoxService.ShowMessage(msg, "确认", MessageButton.YesNo, MessageIcon.Question) == MessageResult.Yes;
        });
        return res;
    }

    /// <summary>
    /// 显示Overlay窗体
    /// </summary>
    public void ShowOverlayForm()
    {
        Invoke(IOverlayService.ShowOverlayForm);
    }

    /// <summary>
    /// 关闭Overlay窗体
    /// </summary>
    public void CloseOverlayForm()
    {
        Invoke(IOverlayService.CloseOverlayForm);
    }

    /// <summary>
    /// 显示SplashScreen等待窗体
    /// </summary>
    /// <param name="caption"></param>
    public void ShowWaitForm(string caption)
    {
        IScreenService.SetSplashScreenState(new string[] { "请稍后", caption });
        IScreenService.ShowSplashScreen("MyWaitForm");
    }

    /// <summary>
    /// 关闭SplashScreen等待窗体
    /// </summary>
    public void CloseWaitForm()
    {
        Invoke(IScreenService.HideSplashScreen);
    }

    /// <summary>
    /// 显示ViewModel对应的View
    /// </summary>
    public void ShowCurrentView()
    {
        ChildViewCancel = true;
        Invoke(ICurrentWindowService.Show);
    }

    /// <summary>
    /// 隐藏ViewModel对应的View
    /// </summary>
    public void HideCurrentView()
    {
        Invoke(ICurrentWindowService.Hide);
    }
    /// <summary>
    /// 子窗体关闭时是否为取消操作状态.默认true
    /// </summary>
    public bool ChildViewCancel { get; set; } = true;

    /// <summary>
    /// 窗体是否为取消状态.默认true
    /// </summary>
    public bool IsCancel { get; set; } = true;

    /// <summary>
    /// 关闭ViewModel对应的View
    /// </summary>
    public void CloseCurrentView()
    {
        Invoke(ICurrentWindowService.Close);
        var pVm = this.GetParentViewModel<BaseVm>();
        pVm.ChildViewCancel = IsCancel;
    }

    /// <summary>
    /// 显示指定的View
    /// </summary>
    public void ShowView(string view, string title, object parameter)
    {
        ChildViewCancel = true;
        IWindowService.Title = title;
        IWindowService.Show(view, parameter, this);
    }


    /// <summary>
    /// 隐藏ShowView指定的View
    /// </summary>
    public void HideView()
    {
        IWindowService.Hide();
    }

    /// <summary>
    /// 关闭ShowView指定的View
    /// </summary>
    public void CloseView()
    {
        IWindowService.Title = "UserClosed";
        IWindowService.Close();
        var pVm = this.GetParentViewModel<BaseVm>();
        pVm.ChildViewCancel = IsCancel;
    }

    public MessageResult ShowDialogView(string view, string title, MessageButton btn = MessageButton.OKCancel)
    {
        return IDialogService.ShowDialog(MessageButton.OKCancel, title, view, this);
    }
    #region service
    IDispatcherService IDispatchService => this.GetService<IDispatcherService>();
    INotificationService INotifyService => this.GetService<INotificationService>();
    IMessageBoxService IMsgBoxService => this.GetService<IMessageBoxService>();
    IOverlayFormService IOverlayService => this.GetService<IOverlayFormService>();
    ISplashScreenService IScreenService => this.GetService<ISplashScreenService>();
    IFolderBrowserDialogService IFolderService => this.GetService<IFolderBrowserDialogService>();
    ISaveFileDialogService ISaveFileService => this.GetService<ISaveFileDialogService>();
    IOpenFileDialogService IOpenFileService => this.GetService<IOpenFileDialogService>();
    ICurrentWindowService ICurrentWindowService => this.GetService<ICurrentWindowService>();
    IWindowService IWindowService => this.GetService<IWindowService>();
    IDialogService IDialogService => this.GetService<IDialogService>();
    #endregion
}