using System;
using System.Collections.Generic;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media.Imaging;
using Microsoft.Win32;
using System.Drawing;
using System.IO;
using System.Xml.Serialization;
using System.Threading.Tasks;
using System.Threading;

namespace ConstRectCropImage
{
    enum EnumResultImgType
    {
        OrigImgWithCropRect,
        CroppedImg,
    }

    /// <summary>
    /// MainWindow.xaml 的交互逻辑
    /// </summary>
    public partial class MainWindow : Window
    {

        #region private variables

        private BitmapImage _origimg;
        private volatile int _currentIndex = 0;
        private string _currentImgFolder;

        private List<ImgInfoForSegEntity> _cropdatas = new List<ImgInfoForSegEntity>();

        private System.Windows.Media.Brush _roiColor = System.Windows.Media.Brushes.Orange;
        private System.Drawing.Point _startpoint;
        private System.Drawing.Point _endpoint;
        private System.Drawing.Rectangle _drawingroi = System.Drawing.Rectangle.Empty;
        private readonly ManualResetEvent _drawFinishEvent = new ManualResetEvent(false);

        #endregion

        public MainWindow()
        {
            InitializeComponent();
            _origimg = null;
            OrigImage.Source = _origimg;
        }

        private void OnLoadMultiImagesClick(object sender, RoutedEventArgs e)
        {
            if (_cropdatas.Count > 0)
            {
                MessageBox.Show("请先完成已加载的图像.");
                return;
            }
            System.Windows.Forms.FolderBrowserDialog folderDialog = new System.Windows.Forms.FolderBrowserDialog();
            folderDialog.Description = "请选择需要裁切的文件夹";
            if (folderDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                if (string.IsNullOrEmpty(folderDialog.SelectedPath))
                {
                    MessageBox.Show("保存裁切后图像的文件夹不能为空！");
                    return;
                }
                _currentImgFolder = folderDialog.SelectedPath;
                DirectoryInfo selectedFolder = new DirectoryInfo(folderDialog.SelectedPath);
                Queue<DirectoryInfo> foldersToSearch = new Queue<DirectoryInfo>();
                foldersToSearch.Enqueue(selectedFolder);
                while (foldersToSearch.Count > 0)
                {
                    DirectoryInfo folder = foldersToSearch.Dequeue();
                    if (!folder.Exists)
                    {
                        continue;
                    }
                    // 搜索子文件夹
                    DirectoryInfo[] subFolders = folder.GetDirectories();
                    foreach (DirectoryInfo subFolder in subFolders)
                    {
                        foldersToSearch.Enqueue(new DirectoryInfo(subFolder.FullName));
                    }
                    // 遍历当前文件夹中所有图片
                    FileInfo[] files = folder.GetFiles();
                    foreach (FileInfo file in files)
                    {
                        string fileName = file.FullName;
                        string fileLocalPath = fileName.Substring(_currentImgFolder.Length + 1);
                        string imgId = Path.GetFileNameWithoutExtension(fileName);
                        ImgInfoForSegEntity imgInfo = new ImgInfoForSegEntity
                        {
                            ImgId = imgId,
                            ImgLocalPath = fileLocalPath,
                        };
                        _cropdatas.Add(imgInfo);
                    }
                }
                _currentIndex = 0;
                CurrentIndexUpdated();
            }
        }

        private void Canvas_SizeChanged(object sender, SizeChangedEventArgs e)
        {
            MyCanvas.Width = GridOrigImg.ActualWidth;
            MyCanvas.Height = GridOrigImg.ActualHeight;
            ImageUpdated();
            DrawingROIUpdated();
        }

        private void Canvas_MouseLeftBtnDown(object sender, MouseButtonEventArgs e)
        {
            int x = Convert.ToInt32(e.GetPosition(OrigImage).X / OrigImage.ActualWidth * _origimg.Width);
            int y = Convert.ToInt32(e.GetPosition(OrigImage).Y / OrigImage.ActualHeight * _origimg.Height);
            _startpoint = new System.Drawing.Point(x, y);
        }

        private void Canvas_MouseMove(object sender, MouseEventArgs e)
        {
            int x = Convert.ToInt32(e.GetPosition(OrigImage).X / OrigImage.ActualWidth * _origimg.Width);
            int y = Convert.ToInt32(e.GetPosition(OrigImage).Y / OrigImage.ActualHeight * _origimg.Height);
            MousePosition.Text = x.ToString() + "," + y.ToString();

            if (e.LeftButton == MouseButtonState.Pressed)
            {
                _endpoint = new System.Drawing.Point(x, y);
                DrawingROIUpdated();
            }
        }

        private void SaveCropDatasClick(object sender, RoutedEventArgs e)
        {
            if (_cropdatas.Count <= 0)
            {
                MessageBox.Show("未找到需保存的数据");
                return;
            }
            if (!_cropdatas[_currentIndex].SegSucceed)
            {
                if (!UseCurrentRoi())
                {
                    return;
                }
            }
            EnumResultImgType resulttype = EnumResultImgType.OrigImgWithCropRect;
            if (RadioBtnResultCropped.IsChecked ?? false)
            {
                resulttype = EnumResultImgType.CroppedImg;
            }
            System.Windows.Forms.FolderBrowserDialog dstFolderD = new System.Windows.Forms.FolderBrowserDialog();
            dstFolderD.Description = "请选择保存裁切后图像的文件夹";
            if (dstFolderD.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                if (string.IsNullOrEmpty(dstFolderD.SelectedPath))
                {
                    MessageBox.Show("保存裁切后图像的文件夹不能为空！");
                    return;
                }
                Task.Run(() =>
                {
                    try
                    {
                        foreach (ImgInfoForSegEntity img in _cropdatas)
                        {
                            string filename = img.ImgLocalPath;
                            Bitmap img_orig = new Bitmap(Bitmap.FromFile(_currentImgFolder + "\\" + filename));
                            int imgWidth = img_orig.Width;
                            int imgHeight = img_orig.Height;
                            if (!img.SegSucceed || (img.Left == 0 && img.Right == 0 && img.Top == 0 && img.Bottom == 0))
                            {
                                if (imgWidth <= _drawingroi.Right || imgHeight <= _drawingroi.Height)
                                {
                                    _drawFinishEvent.Reset();
                                    MessageBox.Show("请重新画框！");
                                    _drawFinishEvent.WaitOne();
                                }
                                img.Left = _drawingroi.Left;
                                img.Top = _drawingroi.Top;
                                img.Right = _drawingroi.Right;
                                img.Bottom = _drawingroi.Bottom;
                                img.SegSucceed = true;
                            }

                            Bitmap dstimg = null;
                            if (resulttype == EnumResultImgType.CroppedImg)
                            {
                                dstimg = new Bitmap(_drawingroi.Width, _drawingroi.Height, img_orig.PixelFormat);
                                using (var g = Graphics.FromImage(dstimg))
                                {
                                    g.DrawImage(img_orig, new System.Drawing.Rectangle(0, 0, _drawingroi.Width, _drawingroi.Height),
                                        new System.Drawing.Rectangle(_drawingroi.Left, _drawingroi.Top, _drawingroi.Width, _drawingroi.Height),
                                        GraphicsUnit.Pixel);
                                    g.Dispose();
                                }
                            }
                            if (resulttype == EnumResultImgType.OrigImgWithCropRect)
                            {
                                dstimg = img_orig.Clone(new Rectangle(0, 0, img_orig.Width, img_orig.Height), img_orig.PixelFormat);
                                using (var g = Graphics.FromImage(dstimg))
                                {
                                    g.DrawRectangle(new System.Drawing.Pen(System.Drawing.Color.Yellow, 8), _drawingroi);
                                    g.Dispose();
                                }
                            }
                            string fileRawName = Path.GetFileNameWithoutExtension(filename);
                            dstimg.Save(dstFolderD.SelectedPath + "\\" + fileRawName+".jpg",System.Drawing.Imaging.ImageFormat.Jpeg);
                            dstimg.Dispose();
                            img_orig.Dispose();
                            _currentIndex += 1;
                        }

                        XmlSerializer xmls = new XmlSerializer(_cropdatas.GetType());
                        FileInfo fileinfo = new FileInfo(dstFolderD.SelectedPath + "\\croppeddatas.xml");
                        if (fileinfo.Exists)
                        {
                            fileinfo.Delete();
                        }
                        using (Stream s = fileinfo.OpenWrite())
                        {
                            xmls.Serialize(s, _cropdatas);
                        }
                        _cropdatas.Clear();
                        MessageBox.Show("完成");
                    }
                    catch (Exception excep)
                    {
                        MessageBox.Show("出错了！" + excep);
                    }
                });
            }
        }

        private bool UseCurrentRoi()
        {
            if (!_startpoint.IsEmpty && !_endpoint.IsEmpty)
            {
                int roileft = Math.Min(_startpoint.X, _endpoint.X);
                int roiright = Math.Max(_startpoint.X, _endpoint.X);
                int roitop = Math.Min(_startpoint.Y, _endpoint.Y);
                int roibottom = Math.Max(_startpoint.Y, _endpoint.Y);
                if (roileft == roiright || roitop == roibottom)
                {
                    MessageBox.Show("绘制的矩形框尺寸不能为0.");
                    return false;
                }
                _drawingroi = new System.Drawing.Rectangle(roileft, roitop, roiright - roileft, roibottom - roitop);
                _cropdatas[_currentIndex].Left = roileft;
                _cropdatas[_currentIndex].Top = roitop;
                _cropdatas[_currentIndex].Right = roiright;
                _cropdatas[_currentIndex].Bottom = roibottom;
                _cropdatas[_currentIndex].SegSucceed = true;
                return true;
            }
            else
            {
                MessageBox.Show("请先加载待测图像并绘制有效的ROI");
                return false;
            }
        }

        private void DrawingROIUpdated()
        {
            if (null == _origimg)
            {
                return;
            }

            System.Windows.Shapes.Rectangle drawingroi = MyCanvas.FindName("drawingroi") as System.Windows.Shapes.Rectangle;
            if (drawingroi != null)
            {
                MyCanvas.Children.Remove(drawingroi);
                MyCanvas.UnregisterName("drawingroi");
            }

            if (_startpoint.IsEmpty || _endpoint.IsEmpty)
            {
                return;
            }

            // 在原始图像上的坐标
            int roileft = Math.Min(_startpoint.X, _endpoint.X);
            int roiright = Math.Max(_startpoint.X, _endpoint.X);
            int roitop = Math.Min(_startpoint.Y, _endpoint.Y);
            int roibottom = Math.Max(_startpoint.Y, _endpoint.Y);

            ROI.Text = roileft.ToString() + "," + roitop + "," + roiright.ToString() + "," + roibottom.ToString();

            // 求在画布上的坐标
            double boxTopInCanvas = roitop * OrigImgScaleTramsform.ScaleY;
            double boxLeftInCanvas = roileft * OrigImgScaleTramsform.ScaleX;
            double boxWidthInCanvas = (roiright - roileft) * OrigImgScaleTramsform.ScaleX;
            double boxHeghtInCanvas = (roibottom - roitop) * OrigImgScaleTramsform.ScaleY;

            // 在画布上画矩形
            drawingroi = new System.Windows.Shapes.Rectangle();
            drawingroi.StrokeThickness = 3;
            drawingroi.Stroke = _roiColor;
            drawingroi.Width = boxWidthInCanvas;
            drawingroi.Height = boxHeghtInCanvas;
            Canvas.SetLeft(drawingroi, boxLeftInCanvas);
            Canvas.SetTop(drawingroi, boxTopInCanvas);
            MyCanvas.Children.Add(drawingroi);
            MyCanvas.RegisterName("drawingroi", drawingroi);
        }

        private void ImageUpdated()
        {
            if (null == _origimg)
            {
                return;
            }

            // 缩放
            double ratioW = GridOrigImg.ActualWidth / _origimg.Width;
            double ratioH = GridOrigImg.ActualHeight / _origimg.Height;
            double ratio = ratioW < ratioH ? ratioW : ratioH;
            OrigImgScaleTramsform.CenterX = 0;
            OrigImgScaleTramsform.CenterY = 0;
            OrigImgScaleTramsform.ScaleX = ratio;
            OrigImgScaleTramsform.ScaleY = ratio;

            // 使图像居中，需要平移
            double translateX = 0;
            double translateY = 0;
            if (Math.Abs(ratio - ratioW) < 0.0001)
            {
                translateY = 0.5 * (ratioH - ratio) * _origimg.Height;
            }
            else
            {
                translateX = 0.5 * (ratioW - ratio) * _origimg.Width;
            }

            // 更新画布尺寸，使其刚好只覆盖图像区域
            MyCanvas.Width = ratio * _origimg.Width;
            MyCanvas.Height = ratio * _origimg.Height;
            Canvas.SetLeft(MyCanvas, translateX);
            Canvas.SetTop(MyCanvas, translateY);
            MyCanvas.ClipToBounds = true;

            OrigImage.Source = _origimg;
        }

        private void CurrentIndexUpdated()
        {
            ImgInfoForSegEntity imginfo = _cropdatas[_currentIndex];
            Bitmap image = new Bitmap(_currentImgFolder + "\\" + imginfo.ImgLocalPath);
            _origimg = ImageUtility.BitmapToBitmapImage(image);
            if (imginfo.Left != 0 || imginfo.Right != 0 || imginfo.Top != 0 || imginfo.Bottom != 0)
            {
                _startpoint = new System.Drawing.Point(imginfo.Left, imginfo.Top);
                _endpoint = new System.Drawing.Point(imginfo.Right, imginfo.Bottom);
                _drawingroi = new System.Drawing.Rectangle(imginfo.Left, imginfo.Top, imginfo.Right - imginfo.Left, imginfo.Bottom - imginfo.Top);
            }
            ImageUpdated();
            DrawingROIUpdated();
            ROI.Text = string.Empty;
        }

        private void UseCurrentRoiClick(object sender, RoutedEventArgs e)
        {
            if (UseCurrentRoi())
            {
                _drawFinishEvent.Set();
            }
        }
    }
}