using System;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using Microsoft.Win32;
using AutoFocusTool.Imaging;

namespace AutoFocusTool
{
    // 抓帧显示 / 实时预览 / 曝光增益 / 光源 / 存图
    public partial class MainWindow
    {
        private byte[] _lastFrame;  // 最近一帧原始 BGR

        /// <summary>抓一帧并刷新显示+清晰度分。返回是否成功。</summary>
        private bool GrabAndShow()
        {
            if (_camera == null) { Log("无相机。"); return false; }
            int r = _camera.GrabRgb();
            if (r != 0) { Log($"抓帧失败(code={r})"); return false; }
            byte[] buf = _camera.GetSourceBuffer();
            _lastFrame = buf;

            // 中心 ROI（画面中央 50%）
            var roi = CenterRoi(_camWidth, _camHeight, 0.5);
            double score = Sharpness.Compute(buf, _camWidth, _camHeight, roi);

            var bmp = ImageConverter.ToBitmapSource(buf, _camWidth, _camHeight);
            Dispatcher.Invoke(() =>
            {
                ImgPreview.Source = bmp;
                TxtScore.Text = $"清晰度: {score:F1}";
                DrawRoiOverlay(roi);
            });
            return true;
        }

        private static System.Drawing.Rectangle CenterRoi(int w, int h, double frac)
        {
            int rw = (int)(w * frac), rh = (int)(h * frac);
            return new System.Drawing.Rectangle((w - rw) / 2, (h - rh) / 2, rw, rh);
        }

        // ── 抓一帧 ──
        private void BtnGrab_Click(object sender, RoutedEventArgs e)
        {
            Task.Run(() => GrabAndShow());
        }

        /// <summary>刷新"当前各参数值"显示(曝光/增益/Z/水平)。在UI线程调用。</summary>
        private void UpdateParamDisplay()
        {
            void Upd()
            {
                int exp = _camera?.Exposure ?? ParseInt(TxtExposure.Text, 0);
                string gain = $"R{ParseInt(TxtGainR.Text, 0)} G{ParseInt(TxtGainG.Text, 0)} B{ParseInt(TxtGainB.Text, 0)}";
                TxtCurValues.Text = $"当前值：曝光 {exp}×100µs({exp / 10.0}ms) | 增益 {gain} | Z {_lastZ} | 水平 {_lastH} | well {(_curWell > 0 ? _curWell.ToString() : "--")}";
            }
            if (Dispatcher.CheckAccess()) Upd(); else Dispatcher.BeginInvoke((Action)Upd);
        }

        // ── 实时预览 ──
        private void TglLive_Click(object sender, RoutedEventArgs e)
        {
            if (TglLive.IsChecked == true)
            {
                _liveCts = new CancellationTokenSource();
                var token = _liveCts.Token;
                Log("实时预览开始。");
                Task.Run(async () =>
                {
                    int frames = 0;
                    var sw = System.Diagnostics.Stopwatch.StartNew();
                    while (!token.IsCancellationRequested)
                    {
                        if (!_busy) GrabAndShow();
                        frames++;
                        if (sw.ElapsedMilliseconds >= 1000)
                        {
                            double fps = frames * 1000.0 / sw.ElapsedMilliseconds;
                            Dispatcher.Invoke(() => TxtFps.Text = $"帧率: {fps:F1} fps");
                            frames = 0; sw.Restart();
                        }
                        await Task.Delay(30, token).ContinueWith(_ => { });
                    }
                }, token);
            }
            else
            {
                _liveCts?.Cancel();
                Log("实时预览停止。");
            }
        }

        // ── 曝光 ──
        private void BtnSetExp_Click(object sender, RoutedEventArgs e)
        {
            if (_camera == null) return;
            int exp = ParseInt(TxtExposure.Text, 400);
            int r = _camera.SetExposure(exp);
            Log($"设置曝光 {exp}×100µs = {exp / 10.0}ms (code={r})");
            UpdateParamDisplay();
            // P0-3: 设曝光后传感器需时间生效，等待+丢弃旧帧，再抓显示当前曝光的画面
            if (TglLive.IsChecked != true)
                Task.Run(() =>
                {
                    Thread.Sleep(Math.Max(200, exp / 5));  // 至少2×曝光时间(单位100µs)
                    if (_camera != null) _camera.GrabRgb();  // 丢弃旧曝光的帧
                    GrabAndShow();
                });
        }

        // ── 增益 ──
        private void BtnSetGain_Click(object sender, RoutedEventArgs e)
        {
            if (_camera == null) return;
            byte rr = (byte)ParseInt(TxtGainR.Text, 25);
            byte gg = (byte)ParseInt(TxtGainG.Text, 14);
            byte bb = (byte)ParseInt(TxtGainB.Text, 25);
            int r = _camera.SetGain(rr, gg, bb);
            Log($"设置增益 R{rr} G{gg} B{bb} (code={r})");
            UpdateParamDisplay();
            if (TglLive.IsChecked != true) Task.Run(() => GrabAndShow());
        }

        // ── 光源 ──
        private void BtnLedOn_Click(object sender, RoutedEventArgs e)
        {
            if (_motor == null) return;
            Task.Run(() => { _busy = true; bool ok = _motor.OpenLED(); _busy = false; Log($"开光源 {(ok ? "OK" : "失败")}"); });
        }

        private void BtnLedOff_Click(object sender, RoutedEventArgs e)
        {
            if (_motor == null) return;
            Task.Run(() => { _busy = true; bool ok = _motor.CloseLED(); _busy = false; Log($"关光源 {(ok ? "OK" : "失败")}"); });
        }

        // ── 存图 ──
        private void BtnSaveImg_Click(object sender, RoutedEventArgs e)
        {
            if (_lastFrame == null) { Log("还没有图像。"); return; }
            var dlg = new SaveFileDialog
            {
                Filter = "BMP 图片|*.bmp",
                FileName = $"house{_current?.HouseSn}_{DateTime.Now:yyyyMMdd_HHmmss}.bmp"
            };
            if (dlg.ShowDialog() == true)
            {
                try
                {
                    ImageConverter.SaveBmp(_lastFrame, _camWidth, _camHeight, dlg.FileName);
                    Log($"已存图: {dlg.FileName}");
                }
                catch (Exception ex) { Log($"存图失败: {ex.Message}"); }
            }
        }
    }
}