using Ink_Canvas.Helpers;
using System;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Ink;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Controls;
using Newtonsoft.Json;
using System.Collections.Generic;
using System.IO;

namespace Ink_Canvas {
    public partial class MainWindow : Window {
        private StrokeCollection[] strokeCollections = new StrokeCollection[101];
        private bool[] whiteboadLastModeIsRedo = new bool[101];
        private StrokeCollection lastTouchDownStrokeCollection = new StrokeCollection();

        private int CurrentWhiteboardIndex = 1;
        private int WhiteboardTotalCount = 1;
        private TimeMachineHistory[][] TimeMachineHistories = new TimeMachineHistory[101][]; //最多99页，0用来存储非白板时的墨迹以便还原

        // 保存每页白板图片信息
        private void SaveStrokes(bool isBackupMain = false) {
            if (isBackupMain) {
                var timeMachineHistory = timeMachine.ExportTimeMachineHistory();
                TimeMachineHistories[0] = timeMachineHistory;
                timeMachine.ClearStrokeHistory();
            } else {
                // 新增：提交所有图片元素到时间机器历史记录
                foreach (var child in inkCanvas.Children)
                {
                    if (child is Image img)
                    {
                        timeMachine.CommitElementInsertHistory(img);
                    }
                }
                
                var timeMachineHistory = timeMachine.ExportTimeMachineHistory();
                TimeMachineHistories[CurrentWhiteboardIndex] = timeMachineHistory;
                timeMachine.ClearStrokeHistory();
                // 保存当前页图片信息
                var elementInfos = new List<CanvasElementInfo>();
                foreach (var child in inkCanvas.Children)
                {
                    if (child is Image img && img.Source is BitmapImage bmp)
                    {
                        elementInfos.Add(new CanvasElementInfo
                        {
                            Type = "Image",
                            SourcePath = bmp.UriSource?.LocalPath ?? "",
                            Left = InkCanvas.GetLeft(img),
                            Top = InkCanvas.GetTop(img),
                            Width = img.Width,
                            Height = img.Height
                        });
                    }
                }
                var savePath = Settings.Automation.AutoSavedStrokesLocation;
                if (!Directory.Exists(savePath)) Directory.CreateDirectory(savePath);
                File.WriteAllText(System.IO.Path.Combine(savePath, $"elements_page{CurrentWhiteboardIndex}.json"), JsonConvert.SerializeObject(elementInfos, Formatting.Indented));
            }
        }

        private void ClearStrokes(bool isErasedByCode) {
            _currentCommitType = CommitReason.ClearingCanvas;
            if (isErasedByCode) _currentCommitType = CommitReason.CodeInput;
            inkCanvas.Strokes.Clear();
            _currentCommitType = CommitReason.UserInput;
        }

        // 恢复每页白板图片信息
        private void RestoreStrokes(bool isBackupMain = false) {
            try {
                if (TimeMachineHistories[CurrentWhiteboardIndex] == null) return; //防止白板打开后不居中
                if (isBackupMain) {
                    timeMachine.ImportTimeMachineHistory(TimeMachineHistories[0]);
                    foreach (var item in TimeMachineHistories[0]) ApplyHistoryToCanvas(item);
                } else {
                    timeMachine.ImportTimeMachineHistory(TimeMachineHistories[CurrentWhiteboardIndex]);
                    // 新增：通过时间机器历史恢复图片
                    foreach (var item in TimeMachineHistories[CurrentWhiteboardIndex])
                    {
                        if (item.CommitType == TimeMachineHistoryType.ElementInsert)
                        {
                            inkCanvas.Children.Add(item.InsertedElement);
                        }
                    }
                    foreach (var item in TimeMachineHistories[CurrentWhiteboardIndex]) ApplyHistoryToCanvas(item);
                    // 恢复当前页图片信息
                    inkCanvas.Children.Clear();
                    var savePath = Settings.Automation.AutoSavedStrokesLocation;
                    var elementsFile = System.IO.Path.Combine(savePath, $"elements_page{CurrentWhiteboardIndex}.json");
                    if (File.Exists(elementsFile))
                    {
                        var elementInfos = JsonConvert.DeserializeObject<List<CanvasElementInfo>>(File.ReadAllText(elementsFile));
                        foreach (var info in elementInfos)
                        {
                            if (info.Type == "Image" && File.Exists(info.SourcePath))
                            {
                                var img = new Image
                                {
                                    Source = new BitmapImage(new Uri(info.SourcePath)),
                                    Width = info.Width,
                                    Height = info.Height,
                                    Stretch = Enum.TryParse<Stretch>(info.Stretch, out var stretch) ? stretch : Stretch.Fill
                                };
                                InkCanvas.SetLeft(img, info.Left);
                                InkCanvas.SetTop(img, info.Top);
                                inkCanvas.Children.Add(img);
                            }
                        }
                    }
                }
            }
            catch {
                // ignored
            }
        }

        private async void BtnWhiteBoardPageIndex_Click(object sender, EventArgs e) {
            if (sender == BtnLeftPageListWB) {
                if (BoardBorderLeftPageListView.Visibility == Visibility.Visible) {
                    AnimationsHelper.HideWithSlideAndFade(BoardBorderLeftPageListView);
                } else {
                    AnimationsHelper.HideWithSlideAndFade(BoardBorderRightPageListView);
                    RefreshBlackBoardSidePageListView();
                    AnimationsHelper.ShowWithSlideFromBottomAndFade(BoardBorderLeftPageListView);
                    await Task.Delay(1);
                    ScrollViewToVerticalTop(
                        (ListViewItem)BlackBoardLeftSidePageListView.ItemContainerGenerator.ContainerFromIndex(
                            CurrentWhiteboardIndex - 1), BlackBoardLeftSidePageListScrollViewer);
                }
            } else if (sender == BtnRightPageListWB)
            {
                if (BoardBorderRightPageListView.Visibility == Visibility.Visible) {
                    AnimationsHelper.HideWithSlideAndFade(BoardBorderRightPageListView);
                } else {
                    AnimationsHelper.HideWithSlideAndFade(BoardBorderLeftPageListView);
                    RefreshBlackBoardSidePageListView();
                    AnimationsHelper.ShowWithSlideFromBottomAndFade(BoardBorderRightPageListView);
                    await Task.Delay(1);
                    ScrollViewToVerticalTop(
                        (ListViewItem)BlackBoardRightSidePageListView.ItemContainerGenerator.ContainerFromIndex(
                            CurrentWhiteboardIndex - 1), BlackBoardRightSidePageListScrollViewer);
                }
            }

        }

        private void BtnWhiteBoardSwitchPrevious_Click(object sender, EventArgs e) {
            if (CurrentWhiteboardIndex <= 1) return;

            SaveStrokes();

            ClearStrokes(true);
            CurrentWhiteboardIndex--;

            RestoreStrokes();

            UpdateIndexInfoDisplay();
        }

        private void BtnWhiteBoardSwitchNext_Click(object sender, EventArgs e) {
            Trace.WriteLine("113223234");

            if (Settings.Automation.IsAutoSaveStrokesAtClear &&
                inkCanvas.Strokes.Count > Settings.Automation.MinimumAutomationStrokeNumber) SaveScreenShot(true);
            if (CurrentWhiteboardIndex >= WhiteboardTotalCount) {
                // 在最后一页时，点击“新页面”按钮直接新增一页
                BtnWhiteBoardAdd_Click(sender, e);
                return;
            }

            SaveStrokes();

            ClearStrokes(true);
            CurrentWhiteboardIndex++;

            RestoreStrokes();

            UpdateIndexInfoDisplay();
        }

        private void BtnWhiteBoardAdd_Click(object sender, EventArgs e) {
            if (WhiteboardTotalCount >= 99) return;
            if (Settings.Automation.IsAutoSaveStrokesAtClear &&
                inkCanvas.Strokes.Count > Settings.Automation.MinimumAutomationStrokeNumber) SaveScreenShot(true);
            SaveStrokes();
            ClearStrokes(true);

            WhiteboardTotalCount++;
            CurrentWhiteboardIndex++;

            if (CurrentWhiteboardIndex != WhiteboardTotalCount)
                for (var i = WhiteboardTotalCount; i > CurrentWhiteboardIndex; i--)
                    TimeMachineHistories[i] = TimeMachineHistories[i - 1];

            UpdateIndexInfoDisplay();

            if (WhiteboardTotalCount >= 99) BtnWhiteBoardAdd.IsEnabled = false;

            if (BlackBoardLeftSidePageListView.Visibility == Visibility.Visible) {
                RefreshBlackBoardSidePageListView();
            }
        }

        private void BtnWhiteBoardDelete_Click(object sender, RoutedEventArgs e) {
            ClearStrokes(true);

            if (CurrentWhiteboardIndex != WhiteboardTotalCount)
                for (var i = CurrentWhiteboardIndex; i <= WhiteboardTotalCount; i++)
                    TimeMachineHistories[i] = TimeMachineHistories[i + 1];
            else
                CurrentWhiteboardIndex--;

            WhiteboardTotalCount--;

            RestoreStrokes();

            UpdateIndexInfoDisplay();

            if (WhiteboardTotalCount < 99) BtnWhiteBoardAdd.IsEnabled = true;
        }

        private void UpdateIndexInfoDisplay() {
            TextBlockWhiteBoardIndexInfo.Text =
                $"{CurrentWhiteboardIndex}/{WhiteboardTotalCount}";

            bool isLastPage = CurrentWhiteboardIndex == WhiteboardTotalCount;
            bool isMaxPage = WhiteboardTotalCount >= 99;

            // 设置按钮文本
            BtnLeftWhiteBoardSwitchNextLabel.Text = isLastPage ? "新页面" : "下一页";
            BtnRightWhiteBoardSwitchNextLabel.Text = isLastPage ? "新页面" : "下一页";

            // 始终允许点击“下一页/新页面”按钮（除非已达最大页数）
            BtnWhiteBoardSwitchNext.IsEnabled = !isMaxPage;

            // 保持按钮常亮（高亮）
            BtnLeftWhiteBoardSwitchNextGeometry.Brush = new SolidColorBrush(Color.FromArgb(255, 24, 24, 27));
            BtnLeftWhiteBoardSwitchNextLabel.Opacity = 1;
            BtnRightWhiteBoardSwitchNextGeometry.Brush = new SolidColorBrush(Color.FromArgb(255, 24, 24, 27));
            BtnRightWhiteBoardSwitchNextLabel.Opacity = 1;

            BtnWhiteBoardSwitchPrevious.IsEnabled = true;

            if (CurrentWhiteboardIndex == 1) {
                BtnWhiteBoardSwitchPrevious.IsEnabled = false;
                BtnLeftWhiteBoardSwitchPreviousGeometry.Brush = new SolidColorBrush(Color.FromArgb(127, 24, 24, 27));
                BtnLeftWhiteBoardSwitchPreviousLabel.Opacity = 0.5;
                BtnRightWhiteBoardSwitchPreviousGeometry.Brush = new SolidColorBrush(Color.FromArgb(127, 24, 24, 27));
                BtnRightWhiteBoardSwitchPreviousLabel.Opacity = 0.5;
            } else {
                BtnLeftWhiteBoardSwitchPreviousGeometry.Brush = new SolidColorBrush(Color.FromArgb(255, 24, 24, 27));
                BtnLeftWhiteBoardSwitchPreviousLabel.Opacity = 1;
                BtnRightWhiteBoardSwitchPreviousGeometry.Brush = new SolidColorBrush(Color.FromArgb(255, 24, 24, 27));
                BtnRightWhiteBoardSwitchPreviousLabel.Opacity = 1;
            }

            BtnWhiteBoardDelete.IsEnabled = WhiteboardTotalCount != 1;
        }
    }
}