using Basler.Pylon;
using Microsoft.Win32;
using Microsoft.WindowsAPICodePack.Dialogs;
using System;
using System.IO;
using System.Threading.Tasks;

using System.Windows;
using System.Windows.Media.Imaging;

namespace WpfApp1
{
    public partial class MainWindow : Window
    {
        private Camera _camera;
        private string _saveFolder = @"C:\CapturedImages";
        private ICameraInfo? _selectedCameraInfo;
        private bool _isCameraStarted = false;

        public MainWindow()
        {
            InitializeComponent();
            WindowStyle = WindowStyle.None;
            ResizeMode = ResizeMode.NoResize;
            WindowState = WindowState.Maximized;

            ButtonPanel1.IsEnabled = false;
            StatusText.Text = "正在初始化相机...请稍后";
            Task.Run(() => InitializeCameraAsync());
        }

        private async Task InitializeCameraAsync()
        {
            try
            {
                var cameras = CameraFinder.Enumerate();
                if (cameras.Count == 0)
                {
                    Dispatcher.Invoke(() =>
                    {
                        ButtonPanel1.IsEnabled = true;
                        StatusText.Text = "未检测到相机";
                    });
                    return;
                }

                _selectedCameraInfo = cameras[0];

                await Task.CompletedTask;

                Dispatcher.Invoke(() =>
                {
                    ButtonPanel1.IsEnabled = true;
                    StatusText.Text = "相机初始化完成，请选择相机并随后‘开启推流’开始取流";
                    StartCameraButton.Content = "开启推流";
                });
            }
            catch (Exception ex)
            {
                Dispatcher.Invoke(() => MessageBox.Show("初始化失败: " + ex.Message));
            }
        }

        private void StartCameraButton_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                // 确保相机已打开
                if ((_camera == null || !_camera.IsOpen) && _selectedCameraInfo != null)
                {
                    if (_camera != null)
                    {
                        try
                        {
                            _camera.StreamGrabber.Stop();
                            _camera.StreamGrabber.ImageGrabbed -= OnImageGrabbed;
                            _camera.Close();
                        }
                        catch { }
                        finally { _camera = null; }
                    }

                    _camera = new Camera(_selectedCameraInfo);
                    _camera.Open();
                    _camera.Parameters[PLCamera.AcquisitionMode].SetValue(PLCamera.AcquisitionMode.Continuous);
                }

                if (_camera == null || !_camera.IsOpen)
                {
                    StatusText.Text = "请先选择一个相机";
                    return;
                }

                if (!_isCameraStarted)
                {
                    _camera.StreamGrabber.ImageGrabbed += OnImageGrabbed;
                    _camera.StreamGrabber.Start(GrabStrategy.LatestImages, GrabLoop.ProvidedByStreamGrabber);
                    _isCameraStarted = true;
                    StatusText.Text = "推流已开启";
                    StartCameraButton.Content = "关闭推流";
                }
                else
                {
                    try
                    {
                        _camera.StreamGrabber.Stop();
                        _camera.StreamGrabber.ImageGrabbed -= OnImageGrabbed;
                        _isCameraStarted = false;
                        StatusText.Text = "推流已关闭";
                        StartCameraButton.Content = "开启推流";
                    }
                    catch (Exception ex)
                    {
                        StatusText.Text = "关闭推流失败：" + ex.Message;
                    }
                }
            }
            catch (Exception ex)
            {
                StatusText.Text = "推流切换失败：" + ex.Message;
            }
        }

        private void OnImageGrabbed(object sender, ImageGrabbedEventArgs e)
        {
            try
            {
                using (IGrabResult result = e.GrabResult)
                {
                    if (!result.GrabSucceeded) return;

                    var converter = new PixelDataConverter();
                    converter.OutputPixelFormat = PixelType.BGRA8packed;

                    byte[] buffer = new byte[result.Width * result.Height * 4];
                    converter.Convert(buffer, result);

                    Dispatcher.Invoke(() =>
                    {
                        CameraImage.Source = BitmapSource.Create(
                            result.Width, result.Height, 96, 96,
                            System.Windows.Media.PixelFormats.Bgra32,
                            null, buffer, result.Width * 4);
                    });
                }
            }
            catch
            {
                // 忽略异常
            }
        }

        private void CaptureButton_Click(object sender, RoutedEventArgs e)
        {
            if (CameraImage.Source == null)
            {
                StatusText.Text = "没有图像可保存";
                return;
            }

            try
            {
                string filePath = Path.Combine(_saveFolder,
                    $"Capture_{DateTime.Now:yyyyMMdd_HHmmss}.png");

                SaveImage(CameraImage.Source as BitmapSource, filePath);

                StatusText.Text = $"图像已保存到：{filePath}";
            }
            catch (Exception ex)
            {
                StatusText.Text = "保存失败：" + ex.Message;
            }
        }

        private void SaveImage(BitmapSource bitmap, string filePath)
        {
            var encoder = new PngBitmapEncoder();
            encoder.Frames.Add(BitmapFrame.Create(bitmap));

            using (FileStream stream = new FileStream(filePath, FileMode.Create))
            {
                encoder.Save(stream);
            }
        }

        private void ChangeFolderButton_Click(object sender, RoutedEventArgs e)
        {
            var selected = FolderHelper.SelectFolder();

            if (selected != null)
            {
                _saveFolder = selected;
                StatusText.Text = $"保存目录已切换为：{_saveFolder}";
            }
        }

        protected override void OnClosing(System.ComponentModel.CancelEventArgs e)
        {
            base.OnClosing(e);

            if (_camera != null)
            {
                try
                {
                    _camera.StreamGrabber.Stop();
                    _camera.StreamGrabber.ImageGrabbed -= OnImageGrabbed;
                    _camera.Close();
                }
                catch (Exception ex)
                {
                    StatusText.Text = "关闭相机时出错：" + ex.Message;
                }
                finally
                {
                    _camera = null;
                    _isCameraStarted = false;
                }
            }
        }

        private void SelectCameraButton_Click(object sender, RoutedEventArgs e)
        {
            var dlg = new SelectCamera();
            dlg.Owner = this;

            if (dlg.ShowDialog() == true)
            {
                var selectedInfo = dlg.SelectedCameraInfo;
                _selectedCameraInfo = selectedInfo;

                // 关闭旧相机，打开新相机，但不取流
                try
                {
                    if (_camera != null)
                    {
                        try
                        {
                            _camera.StreamGrabber.Stop();
                            _camera.StreamGrabber.ImageGrabbed -= OnImageGrabbed;
                            _camera.Close();
                        }
                        catch { }
                        finally { _camera = null; _isCameraStarted = false; }
                    }

                    _camera = new Camera(_selectedCameraInfo);
                    _camera.Open();
                    _camera.Parameters[PLCamera.AcquisitionMode].SetValue(PLCamera.AcquisitionMode.Continuous);

                    _isCameraStarted = false;
                    StatusText.Text = $"已选择并打开相机：{selectedInfo[CameraInfoKey.SerialNumber]}（未取流）。点击‘开启推流’开始/停止推流";
                    StartCameraButton.Content = "开启推流";
                }
                catch (Exception ex)
                {
                    StatusText.Text = "打开相机失败：" + ex.Message;
                }
            }
        }

        private void ExitButton_Click(object sender, RoutedEventArgs e)
        {
            Close();
        }

        private void TimedCaptureButton_Click(object sender, RoutedEventArgs e)
        {
            // 定时拍摄只要求相机已打开，无需取流
            if (_camera == null || !_camera.IsOpen)
            {
                MessageBox.Show("请先选择相机（会自动打开但不取流）");
                return;
            }
            var dlg = new TimedCapture(_camera);
            dlg.Owner = this;
            dlg.ShowDialog();
        }
    }
}