using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;
using AutoFocusTool.Imaging;

namespace AutoFocusTool
{
    // Z序列扫描选层 + 清晰度曲线 + ROI叠加
    public partial class MainWindow
    {
        // ── Z 扫描：逐层移动→等稳→抓帧→算分，画曲线，取全局峰 ──
        private void BtnZScan_Click(object sender, RoutedEventArgs e)
        {
            if (_camera == null || _motor == null) { Log("需要相机+串口都连接。"); return; }
            if (_busy) { Log("串口忙。"); return; }

            int start = ParseInt2(TxtScanStart.Text, 0);
            int step = ParseInt2(TxtScanStep.Text, 128);
            int count = ParseInt2(TxtScanCount.Text, 11);
            int motorDelay = ParseInt2(TxtMotorDelay.Text, 1500);  // UI线程先读好
            if (count < 2) { Log("层数至少2。"); return; }

            _scanCts = new CancellationTokenSource();
            var token = _scanCts.Token;

            Task.Run(() =>
            {
                _busy = true;
                _curve.Clear();
                try
                {
                    if (_motor != null) _motor.MotorDelayMs = motorDelay;
                    Log($"=== Z扫描开始: 起点{start} 层距{step} 层数{count} ===");
                    _motor.OpenLED();
                    Thread.Sleep(200);

                    for (int i = 0; i < count; i++)
                    {
                        if (token.IsCancellationRequested) { Log("扫描已停止。"); break; }
                        int z = start + step * i;

                        // 移动到该层（开环，VerticalMoveTo 内含 motorDelay 等待）
                        if (!_motor.VerticalMoveTo(z))
                            Log($"层{i + 1}: Z移动到{z} 失败（继续）");

                        // P0-2: 移动后相机缓冲区可能是移动前的旧帧，丢弃第1帧用第2帧
                        if (_camera.GrabRgb() != 0) { Log($"层{i + 1}: 抓帧失败"); continue; }
                        int gr = _camera.GrabRgb();
                        if (gr != 0) { Log($"层{i + 1}: 抓帧失败"); continue; }
                        byte[] buf = _camera.GetSourceBuffer();

                        // ROI统一：先检well圆用圆内0.95r ROI(与精对焦一致)，检不出降级中央40%
                        var circle = WellDetector.Detect(buf, _camWidth, _camHeight);
                        var roi = circle.Found
                            ? new System.Drawing.Rectangle(
                                Math.Max(0, (int)(circle.Cx - circle.Radius * 0.95)),
                                Math.Max(0, (int)(circle.Cy - circle.Radius * 0.95)),
                                (int)(circle.Radius * 1.9), (int)(circle.Radius * 1.9))
                            : CenterRoi(_camWidth, _camHeight, 0.4);
                        double score = Sharpness.Compute(buf, _camWidth, _camHeight, roi);
                        _curve.Add((z, score));
                        Log($"层{i + 1}/{count}: Z={z} 清晰度={score:F1}{(circle.Found ? "" : "(全图降级:未检出圆)")}");

                        // 实时刷新画面+曲线
                        var bmp = ImageConverter.ToBitmapSource(buf, _camWidth, _camHeight);
                        Dispatcher.Invoke(() =>
                        {
                            ImgPreview.Source = bmp;
                            TxtScore.Text = $"清晰度: {score:F1}";
                            TxtZ.Text = $"Z: {z}";
                            DrawCurve();
                        });
                    }

                    _motor.CloseLED();

                    // 选层：全局峰 + 单峰/全糊判据
                    AnalyzeCurve();
                }
                catch (Exception ex) { Log($"扫描异常: {ex.Message}"); }
                finally { _busy = false; }
            }, token);
        }

        private void BtnStop_Click(object sender, RoutedEventArgs e)
        {
            _scanCts?.Cancel();
            _liveCts?.Cancel();
            _calibCts?.Cancel();
            Log("已请求停止。");
        }

        /// <summary>分析曲线：取全局峰，判断是否"全糊"。</summary>
        private void AnalyzeCurve()
        {
            if (_curve.Count == 0) { Log("无数据。"); return; }
            var scores = _curve.Select(c => c.score).ToList();
            double max = scores.Max();
            double mean = scores.Average();
            int peakIdx = scores.IndexOf(max);
            int peakZ = _curve[peakIdx].z;

            // 全糊判据：峰值/均值接近1 且 曲线平 → 没有明显焦点
            double ratio = mean > 1e-6 ? max / mean : 1;
            bool allBlur = ratio < 1.15; // 经验阈值，真机标定

            if (allBlur)
            {
                Log($"⚠ 整组偏糊：最高分层{peakIdx + 1}(Z={peakZ}) 分={max:F1}，但 max/mean={ratio:F2} 偏低，可能无真实焦点（需扩范围搜索或空孔）。");
            }
            else
            {
                Log($"★ 最清晰层 = 第{peakIdx + 1}层 Z={peakZ} 分={max:F1}（max/mean={ratio:F2}）");
                // 移动到最清晰层
                Task.Run(() =>
                {
                    _busy = true;
                    try { _motor.VerticalMoveTo(peakZ); Log($"已移动到最清晰层 Z={peakZ}"); }
                    finally { _busy = false; }
                    RefreshPositions();
                });
            }
            Dispatcher.Invoke(() => DrawCurve(peakIdx));
        }

        // ── 曲线绘制 ──
        private void DrawCurve(int peakIdx = -1)
        {
            var canvas = CurveCanvas;
            canvas.Children.Clear();
            if (_curve.Count < 2) return;

            double w = canvas.ActualWidth, h = canvas.ActualHeight;
            if (w < 10 || h < 10) return;

            double min = _curve.Min(c => c.score);
            double max = _curve.Max(c => c.score);
            double range = max - min;
            if (range < 1e-6) range = 1;

            double dx = w / (_curve.Count - 1);
            var poly = new Polyline { Stroke = Brushes.Aqua, StrokeThickness = 2 };
            for (int i = 0; i < _curve.Count; i++)
            {
                double x = i * dx;
                double y = h - 10 - (_curve[i].score - min) / range * (h - 20);
                poly.Points.Add(new Point(x, y));

                var dot = new Ellipse { Width = 6, Height = 6, Fill = (i == peakIdx) ? Brushes.Orange : Brushes.Aqua };
                Canvas.SetLeft(dot, x - 3); Canvas.SetTop(dot, y - 3);
                canvas.Children.Add(dot);
            }
            canvas.Children.Add(poly);

            if (peakIdx >= 0)
            {
                double px = peakIdx * dx;
                var line = new Line { X1 = px, Y1 = 0, X2 = px, Y2 = h, Stroke = Brushes.Orange, StrokeThickness = 1, StrokeDashArray = new DoubleCollection { 3, 3 } };
                canvas.Children.Add(line);
            }
        }

        // ── ROI 叠加框 ──
        private void DrawRoiOverlay(System.Drawing.Rectangle roi)
        {
            OverlayCanvas.Children.Clear();
            double iw = ImgPreview.ActualWidth, ih = ImgPreview.ActualHeight;
            if (iw < 10 || ih < 10) return;
            // 图像按 Uniform 缩放，ROI 同比例映射
            double sx = iw / _camWidth, sy = ih / _camHeight;
            double s = Math.Min(sx, sy);
            double offX = (iw - _camWidth * s) / 2, offY = (ih - _camHeight * s) / 2;

            var rect = new Rectangle
            {
                Stroke = Brushes.Lime,
                StrokeThickness = 2,
                Width = roi.Width * s,
                Height = roi.Height * s,
                StrokeDashArray = new DoubleCollection { 4, 2 }
            };
            Canvas.SetLeft(rect, offX + roi.X * s);
            Canvas.SetTop(rect, offY + roi.Y * s);
            OverlayCanvas.Children.Add(rect);
        }
    }
}