using Microsoft.Win32;
using PDF_Office.CustomControl.SystemControl;
using PDF_Office.Model;
using PDF_Office.EventAggregators;
using PDF_Office.Views;
using Prism.Commands;
using Prism.Events;
using Prism.Mvvm;
using Prism.Regions;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Controls;
using ComPDFKitViewer.PdfViewer;
using Dragablz;
using System.Windows;
using Prism.Ioc;
using PDF_Office.CustomControl;

namespace PDF_Office.ViewModels
{
    public class MainWindowViewModel : BindableBase
    {
        private MainContent selectedItem;

        public MainContent SelectedItem
        {
            get { return selectedItem; }
            set {
                SetProperty(ref selectedItem, value);
                if (SelectedItem!=null)
                {
                    var pdfviewer = (SelectedItem.DataContext as MainContentViewModel).PDFViewer;
                    if(pdfviewer!=null)
                    {
                        CurrentPDFViewer = pdfviewer;
                    }
                    else
                    {
                        CurrentPDFViewer = null;
                    }
                }
            }
        }

        private double processvalue = 0;
        /// <summary>
        /// 进度条当前值
        /// </summary>
        public double Value
        {
            get { return processvalue; }
            set
            {
                SetProperty(ref processvalue, value);
            }
        }

        private double maxValue = 100;
        /// <summary>
        /// 进度条最大值
        /// </summary>
        public double MaxValue
        {
            get { return maxValue; }
            set
            {
                SetProperty(ref maxValue, value);
            }
        }


        private Visibility isProcessVisible = Visibility.Collapsed;
        /// <summary>
        /// OCR进度条是否显示
        /// </summary>
        public Visibility IsProcessVisible
        {
            get { return isProcessVisible; }
            set
            {
                SetProperty(ref isProcessVisible, value);
            }
        }

        private bool isCloseAllEnable = false;

        public bool IsCloseAllEnable
        {
            get { return isCloseAllEnable; }
            set
            {
                SetProperty(ref isCloseAllEnable, value);
            }
        }

        public DelegateCommand CloseAllTabCommand { get; set; }


        /// <summary>
        /// 进度条关闭的事件
        /// </summary>
        public Action ProcessCloseAction;


        private CPDFViewer pdfViewer;

        /// <summary>
        /// 当前页签的PdfViewer对象
        /// </summary>
        public CPDFViewer CurrentPDFViewer
        {
            get { return pdfViewer; }
            set { pdfViewer = value; }
        }

        public DelegateCommand AddTab { get; set; }

        /// <summary>
        /// 关闭OCR进度条
        /// </summary>
        public DelegateCommand CloseOCRCommand { get; set; }

        public IRegionManager region;

        public IEventAggregator eventer;

        private IContainerProvider containerProvider;

        public IInterTabClient InterTabClient { get; }

        public MainWindowViewModel(IRegionManager regionManager, IEventAggregator eventAggregator, IContainerProvider container)
        {
            if (App.mainWindowViewModel == null)
            {
                //加载第一个窗体时 先赋值静态对象
                App.mainWindowViewModel = this;
            }

            region = regionManager;

            eventer = eventAggregator;

            containerProvider = container;

            InterTabClient = new InterTabClient(container);

            AddTab = new DelegateCommand(AddTabItem);
            CloseOCRCommand = new DelegateCommand(closeocr);
            CloseAllTabCommand = new DelegateCommand(()=> { closeAllTabItem(); });

            //第一次打开时需要自动加载Home页
            if (App.IsFirstOpen)
            {
                System.Windows.Application.Current.Dispatcher.BeginInvoke(System.Windows.Threading.DispatcherPriority.Send, new Action(() =>
                {
                    region.RequestNavigate(RegionNames.MainRegion, "MainContent");
                }
                ));
                App.IsFirstOpen = false;
            }
        }

        /// <summary>
        /// 关闭OCR
        /// </summary>
        private void closeocr()
        {
            if(ProcessCloseAction!=null)
            {
                ProcessCloseAction.Invoke();
            }
        }

        /// <summary>
        /// 单击+号时添加页签
        /// </summary>
        private void AddTabItem()
        {
            region.RequestNavigate(RegionNames.MainRegion, "MainContent");
            CheckViewsCount();
        }

        /// <summary>
        /// 选择多文档打开时
        /// </summary>
        /// <param name="filePath"></param>
        public void AddTabItem(string filePath)
        {
            NavigationParameters parameters = new NavigationParameters
            {
                { ParameterNames.FilePath, filePath }
            };
            region.RequestNavigate(RegionNames.MainRegion, "MainContent", parameters);
            CheckViewsCount();
        }


        /// <summary>
        /// 关闭所有页签
        /// </summary>
        public bool closeAllTabItem()
        {
            while (region.Regions[RegionNames.MainRegion].Views.Count() > 0)
            {
                if (CurrentPDFViewer!=null&&CurrentPDFViewer.UndoManager.CanSave)
                {
                    ContentResult result = ShowSaveDialog((SelectedItem.DataContext as MainContentViewModel).viewContentViewModel);
                    if (result == ContentResult.Cancel)
                        return false;
                    App.OpenedFileList.Remove(CurrentPDFViewer.Document.FilePath);
                    CurrentPDFViewer.CloseDocument();
                }
                if (selectedItem != null)
                {
                    region.Regions[RegionNames.MainRegion].Remove(selectedItem);
                }

                //多窗体情况下，单个窗体的所有页签均已关闭时，返回true，允许关闭窗体
                if(selectedItem==null)
                {
                    return true;
                }
            }
            return true;
        }

        public void CloseTabItem(object item)
        {
            //获取x号所在的maincontentviewmodel对象
            var maincontentViewModel = (item as MainContent).DataContext as MainContentViewModel;
            //如果已经有打开文档，先切换到目标页签
            if (maincontentViewModel.PDFViewer != null)
            {
                SelectItem(maincontentViewModel.PDFViewer.Document.FilePath);
            }
            if (maincontentViewModel.PDFViewer != null &&maincontentViewModel.PDFViewer.UndoManager.CanSave)
            {
                ContentResult result = ShowSaveDialog(maincontentViewModel.viewContentViewModel);
                if (result == ContentResult.Cancel)
                {
                    return;
                }
                App.OpenedFileList.Remove(maincontentViewModel.PDFViewer.Document.FilePath);
                if (maincontentViewModel.PDFViewer.Document != null)
                {
                    maincontentViewModel.PDFViewer.CloseDocument();
                }

            }
            if (region.Regions[RegionNames.MainRegion].Views.Count() > 1)
            {
                region.Regions[RegionNames.MainRegion].Remove(item);
                CheckViewsCount();
            }
            else
            {
           
                if (maincontentViewModel.PDFViewer != null)
                {
                    //如果是打开文档的页签 则回到首页
                    region.Regions[RegionNames.MainRegion].Remove(item);
                    region.RequestNavigate(RegionNames.MainRegion, "MainContent");
                }
                else
                {
                    //如果是关闭首页则关闭软件
                    region.Regions[RegionNames.MainRegion].Remove(item);
                    App.Current.MainWindow.Close();
                }
            }
            return;

        }

        /// <summary>
        /// 检查页签个数 更新close allcommand 命令状态
        /// </summary>
        private void CheckViewsCount()
        {
            if(region.Regions[RegionNames.MainRegion].Views.Count()>1)
            {
                IsCloseAllEnable = true;
            }
            else
            {
                IsCloseAllEnable = false;
            }
        }

        public void SelectItem(string filepath)
        {
            var item = region.Regions[RegionNames.MainRegion].Views.Where(t => ((t as MainContent).DataContext as MainContentViewModel).FilePath == filepath).FirstOrDefault() as MainContent;
            if (item == null)
                return;

            region.Regions[RegionNames.MainRegion].Activate(item);
            var behavior = region.Regions[RegionNames.MainRegion].Behaviors[DragablzWindowBehavior.BehaviorKey] as DragablzWindowBehavior;
            if(behavior!=null)
            {
                behavior.ActivateView(item);
            }
        }

        /// <summary>
        /// 显示关闭询问弹窗
        /// </summary>
        /// <param name="pdfViewer"></param>
        /// <returns></returns>
        private ContentResult ShowSaveDialog(ViewContentViewModel viewContentViewModel)
        {
            AlertsMessage alertsMessage = new AlertsMessage();
            alertsMessage.ShowDialog("关闭提示","当前文档有为保存的操作，是否需要保存？","Cancel","No","Ok");
            var result = alertsMessage.result;

            if (result == ContentResult.Ok)
            {
                var isSave = viewContentViewModel.saveFile();
                if (isSave == false)
                    result = ContentResult.Cancel;
            }
            return result;
        }
    }
}