/**
 * @file Checks.cpp
 * @brief 离屏检查的具体实现（隐藏窗口 + 合成消息，绝不占用真实鼠标/键盘/屏幕）。
 *
 * 检查清单：
 *  * `smoke`     —— 能建隐藏窗口、能加载数据、能画出波形（像素级）。
 *  * `frames`    —— **连续帧抓取**：沿绘图区移动鼠标，逐帧抓 PNG + 哈希 + 耗时；
 *                   并验证"同一状态连续两帧逐像素相同"（渲染确定性）。
 *  * `panels`    —— 7 种实验性功能面板全部展开后的**几何 + 像素基线**，
 *                   支持 `-mode record` / `-mode compare` 做重构前后 A/B。
 *  * `edgestats` —— 边沿统计与**独立参考实现**逐位比对（覆盖阈值变化、缓存稳定性）。
 *  * `perf`      —— 关键路径耗时：整帧、面板几何、边沿统计查询。
 *
 * ⚠️ 所有 `Expect()` 都是"记录并继续"，单个检查跑完仍然给出完整报告。
 */

#include <chrono>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <limits>
#include <string>
#include <vector>

#include "CheckRunner.hpp"

namespace jdi
{
	namespace tools
	{
		namespace
		{
			/** @brief 各检查共用的临时输出目录（相对项目根，已被 .gitignore 忽略）。 */
			const char* const kDefaultOutDir = "../Temp/tools";

			/** @brief 拼路径。 */
			std::string Join(const std::string& directory, const std::string& name)
			{
				if (directory.empty())
				{
					return name;
				}
				const char last = directory.back();
				if (last == '/' || last == '\\')
				{
					return directory + name;
				}
				return directory + "/" + name;
			}

			/** @brief 把 ASCII/本地代码页路径转宽字符串。 */
			std::wstring Widen(const std::string& text)
			{
				const int length = MultiByteToWideChar(CP_ACP, 0, text.c_str(), -1, nullptr, 0);
				if (length <= 1)
				{
					return std::wstring();
				}
				std::wstring wide(static_cast<std::size_t>(length - 1), L'\0');
				MultiByteToWideChar(CP_ACP, 0, text.c_str(), -1, &wide[0], length);
				return wide;
			}

			/** @brief 在路径中取目录部分。 */
			std::string DirectoryOf(const std::string& path)
			{
				const std::size_t slash = path.find_last_of("/\\");
				return (slash == std::string::npos) ? std::string() : path.substr(0, slash);
			}

			/** @brief 扫描信号的有限采样值范围（不依赖统计字段，便于构造探针阈值）。 */
			void FiniteRange(const std::vector<double>& values, double& low, double& high)
			{
				low = std::numeric_limits<double>::infinity();
				high = -std::numeric_limits<double>::infinity();
				for (const double value : values)
				{
					if (!std::isfinite(value))
					{
						continue;
					}
					low = std::min(low, value);
					high = std::max(high, value);
				}
				if (!std::isfinite(low) || !std::isfinite(high))
				{
					low = 0.0;
					high = 1.0;
				}
			}

			/**
			 * @brief 边沿统计的**独立参考实现**（与 `PlotView::EdgeScanFor` 的契约一致）。
			 *
			 * 契约（源码注释与实测共同确认）：
			 *  * 判定量 `delta = 绘制值 - 阈值`；
			 *  * 采样对 `k-1 → k`：`previous < 0 && current >= 0` 记上升沿，
			 *    `previous > 0 && current <= 0` 记下降沿；
			 *  * 任一端为 NaN（缺失值 / 区间外）则该采样对不计入，并**打断连续性**。
			 *
			 * ⚠️ 这里刻意用最朴素的逐点写法：参考实现宁慢勿巧，才有资格当"金标准"。
			 */
			void ReferenceEdgeCounts(const std::vector<double>& values, const SignalStyle& style,
			                         const double threshold, std::size_t& rising, std::size_t& falling)
			{
				rising = 0;
				falling = 0;
				double previous = std::numeric_limits<double>::quiet_NaN();
				for (std::size_t index = 0; index < values.size(); ++index)
				{
					const double raw = values[index];
					double current = std::numeric_limits<double>::quiet_NaN();
					if (std::isfinite(raw))
					{
						const double drawn = ApplyDrawTransform(style, raw);
						if (std::isfinite(drawn))
						{
							current = drawn - threshold;
						}
					}
					if (std::isfinite(previous) && std::isfinite(current))
					{
						if (previous < 0.0 && current >= 0.0)
						{
							++rising;
						}
						else if (previous > 0.0 && current <= 0.0)
						{
							++falling;
						}
					}
					previous = current;
				}
			}

			/** @brief 查询边沿统计直到完成（每次未完成就再出一帧以重置每帧预算）。 */
			bool CollectEdgeCounts(Session& session, const TimeAxis& axis, const SignalData& signal,
			                       const SignalStyle& style, const double threshold, std::size_t& rising,
			                       std::size_t& falling, int& framesUsed)
			{
				rising = 0;
				falling = 0;
				framesUsed = 0;
				bool complete = false;
				const int maxFrames = 4000;
				while (!complete && framesUsed < maxFrames)
				{
					session.App().m_plot.EdgeCountsFor(axis, signal, style, threshold, false, 0.0, 0.0, rising,
					                                   falling, complete);
					if (complete)
					{
						break;
					}
					session.RenderFrame();
					++framesUsed;
				}
				return complete;
			}

			/** @brief 简单 key=value 基线文件的读取。 */
			std::vector<std::pair<std::string, std::string>> ParseBaseline(const std::string& text)
			{
				std::vector<std::pair<std::string, std::string>> entries;
				std::size_t cursor = 0;
				while (cursor < text.size())
				{
					std::size_t end = text.find('\n', cursor);
					if (end == std::string::npos)
					{
						end = text.size();
					}
					std::string line = text.substr(cursor, end - cursor);
					cursor = end + 1;
					while (!line.empty() && (line.back() == '\r' || line.back() == ' '))
					{
						line.pop_back();
					}
					if (line.empty() || line[0] == '#')
					{
						continue;
					}
					const std::size_t equals = line.find('=');
					if (equals == std::string::npos)
					{
						continue;
					}
					entries.emplace_back(line.substr(0, equals), line.substr(equals + 1));
				}
				return entries;
			}

			/** @brief 面板种类名（打印 / 基线文件键名）。 */
			const char* PanelKindName(const EdgePanelKind kind)
			{
				switch (kind)
				{
				case EdgePanelKind::COUNT:
					return "count";
				case EdgePanelKind::CENTER:
					return "center";
				case EdgePanelKind::MEAN:
					return "mean";
				case EdgePanelKind::PEAK:
					return "peak";
				case EdgePanelKind::MARK:
					return "mark";
				case EdgePanelKind::RESAMPLE:
					return "resample";
				case EdgePanelKind::CLIP:
					return "clip";
				}
				return "unknown";
			}

			/** @brief 确保某个实验性功能已开启（`Toggle*` 是开关语义）。 */
			void EnsureLaneFeature(PlotView& plot, const int laneIndex, const EdgePanelKind kind)
			{
				switch (kind)
				{
				case EdgePanelKind::COUNT:
					if (!plot.LaneEdgeCount(laneIndex))
					{
						plot.ToggleLaneEdgeCount(laneIndex);
					}
					break;
				case EdgePanelKind::CENTER:
					if (!plot.LaneEdgeCenterCount(laneIndex))
					{
						plot.ToggleLaneEdgeCenterCount(laneIndex);
					}
					break;
				case EdgePanelKind::MEAN:
					if (!plot.LaneMeanFilter(laneIndex))
					{
						plot.ToggleLaneMeanFilter(laneIndex);
					}
					break;
				case EdgePanelKind::PEAK:
					if (!plot.LaneWeakPeak(laneIndex))
					{
						plot.ToggleLaneWeakPeak(laneIndex);
					}
					break;
				case EdgePanelKind::MARK:
					if (!plot.LaneFreeMarker(laneIndex))
					{
						plot.ToggleLaneFreeMarker(laneIndex);
					}
					break;
				case EdgePanelKind::RESAMPLE:
					if (!plot.LaneResample(laneIndex))
					{
						plot.ToggleLaneResample(laneIndex);
					}
					break;
				case EdgePanelKind::CLIP:
					if (!plot.LaneClip(laneIndex))
					{
						plot.ToggleLaneClip(laneIndex);
					}
					break;
				}
			}

			// ---- 检查实现 -------------------------------------------------------

			int CheckSmoke(Session& session, const CheckOptions& options)
			{
				int clientWidth = 0;
				int clientHeight = 0;
				session.ClientSize(clientWidth, clientHeight);
				EmitLine("[smoke] client=%dx%d lanes=%d\n", clientWidth, clientHeight, session.LaneCount());

				session.ShowFirstSignals(3);
				Expect(session.RenderFrame(), "render frame");
				Expect(session.LaneCount() > 0, "at least one lane after showing signals");

				const Frame& frame = session.LastFrame();
				Expect(frame.Valid(), "captured frame is valid");

				const PixelRect plot = ToPixelRect(session.PlotArea());
				const int ink = CountInk(frame, plot);
				EmitLine("[smoke] plot rect=(%d,%d,%dx%d) ink=%d render=%.2fms\n", plot.x, plot.y, plot.width,
				         plot.height, ink, session.LastRenderMs());
				Expect(plot.width > 100 && plot.height > 100, "plot area is reasonable");
				Expect(ink > 1000, "plot area has drawn content");

				if (options.savePng)
				{
					const std::string path = Join(options.outDir, "smoke.png");
					Expect(SavePng(frame, path), "save smoke.png");
					EmitLine("[smoke] saved %s\n", path.c_str());
				}

				// 同一状态再渲染一帧：必须逐像素相同（渲染确定性；也验证缓存没有"半帧"状态）
				const Frame first = session.LastFrame();
				Expect(session.RenderFrame(), "render frame again");
				const PixelRect whole{0, 0, session.LastFrame().width, session.LastFrame().height};
				const int drift = CountDiff(first, session.LastFrame(), whole, 0);
				EmitLine("[smoke] determinism: differing pixels between two identical frames = %d\n", drift);
				Expect(drift == 0, "two identical frames are pixel-identical");
				return CheckFailed();
			}

			int CheckFrames(Session& session, const CheckOptions& options)
			{
				session.ShowFirstSignals(2);
				Expect(session.RenderFrame(), "initial render");

				const PixelRect plot = ToPixelRect(session.PlotArea());
				Expect(plot.width > 100, "plot area is wide enough");

				// 抓帧同时扫过**信号列表**：行悬停会改变行底色，因此每帧像素必然不同
				//（比“在空白绘图区里移动鼠标”更能证明“帧序列真的拍到了状态变化”）。
				const gd::RectF panelArea = session.App().m_panel.Area();
				const int panelX = static_cast<int>(panelArea.X + panelArea.Width * 0.5f);
				const int panelTop = static_cast<int>(panelArea.Y) + 60;

				const int frames = std::max(1, options.frames);
				int identicalPairs = 0;
				std::uint64_t previousHash = 0;
				double totalMs = 0.0;
				double worstMs = 0.0;

				for (int index = 0; index < frames; ++index)
				{
					// 沿信号列表纵向移动“鼠标”（合成消息，不动真实光标）
					const int y = panelTop + index * 34;
					session.MouseMove(panelX, y);
					Expect(session.RenderFrame(), "render frame while moving");

					const Frame& frame = session.LastFrame();
					const std::uint64_t hash = HashRegion(frame, plot);

					char name[64] = {};
					std::snprintf(name, sizeof(name), "frame-%03d.png", index);
					if (options.savePng)
					{
						if (!SavePng(frame, Join(options.outDir, name)))
						{
							Expect(false, "save frame png");
						}
					}

					EmitLine("[frames] #%02d mouse=(%d,%d) plot-hash=%016llX render=%.2fms file=%s\n", index, panelX,
					         y, static_cast<unsigned long long>(hash), session.LastRenderMs(), name);

					totalMs += session.LastRenderMs();
					worstMs = std::max(worstMs, session.LastRenderMs());
					if (index > 0 && hash == previousHash)
					{
						++identicalPairs;
						EmitLine("[frames] WARNING: frame %d pixel-identical to previous\n", index);
					}
					previousHash = hash;
				}

				EmitLine("[frames] average=%.2fms worst=%.2fms identical_pairs=%d\n",
				         totalMs / static_cast<double>(frames), worstMs, identicalPairs);
				Expect(totalMs / static_cast<double>(frames) < 500.0, "average frame time below 500ms");
				// 至少要有一次可见变化（某些 y 落在筛选框/空白带，重复是正常的）
				Expect(identicalPairs < frames - 1, "frame sequence captures at least one visual change");
				return CheckFailed();
			}

			int CheckPanels(Session& session, const CheckOptions& options)
			{
				// 单信号单网格：7 个面板都落在同一个网格上，便于逐面板取几何
				session.ShowFirstSignals(1);
				Expect(session.LaneCount() == 1, "exactly one lane");

				Application& app = session.App();
				PlotView& plot = app.m_plot;

				// 「选区截取」要求双光标，先切到双光标模式
				if (app.ActiveTab().CursorMode() != PlotCursorMode::DOUBLE)
				{
					const int guard = 4;
					for (int step = 0; step < guard && app.ActiveTab().CursorMode() != PlotCursorMode::DOUBLE; ++step)
					{
						plot.CycleCursorMode();
					}
				}

				static const EdgePanelKind kinds[] = {EdgePanelKind::COUNT,   EdgePanelKind::CENTER,
				                                      EdgePanelKind::MEAN,    EdgePanelKind::PEAK,
				                                      EdgePanelKind::MARK,    EdgePanelKind::RESAMPLE,
				                                      EdgePanelKind::CLIP};
				for (const EdgePanelKind kind : kinds)
				{
					EnsureLaneFeature(plot, 0, kind);
				}

				Expect(session.RenderFrame(), "render with all panels open");

				const PixelRect plotRect = ToPixelRect(session.PlotArea());
				std::string content;

				for (const EdgePanelKind kind : kinds)
				{
					const PlotView::EdgePanelLayout layout = plot.EdgePanelLayoutFor(0, kind);
					const PixelRect rect = ToPixelRect(layout.panel);
					const Lane& lane = app.ActiveTab().Lanes()[0];
					const bool enabled = LanePanelEnabled(lane, kind);
					const bool open = LanePanelStateOf(lane, kind).open;
					EmitLine("[panels] %-8s enabled=%d open=%d rect=(%d,%d,%dx%d) hash=%016llX\n",
					         PanelKindName(kind), enabled ? 1 : 0, open ? 1 : 0, rect.x, rect.y, rect.width,
					         rect.height, static_cast<unsigned long long>(HashRegion(session.LastFrame(), rect)));

					Expect(enabled, std::string("feature enabled: ") + PanelKindName(kind));
					Expect(rect.width > 0 && rect.height > 0,
					       std::string("panel has size: ") + PanelKindName(kind));

					// 不变式：面板必须被绘图区夹住（这是历史上"面板超出绘图区"缺陷的护栏）
					const bool inside = rect.x >= plotRect.x - 1 && rect.y >= plotRect.y - 1 &&
					                    rect.x + rect.width <= plotRect.x + plotRect.width + 1 &&
					                    rect.y + rect.height <= plotRect.y + plotRect.height + 1;
					Expect(inside, std::string("panel inside plot area: ") + PanelKindName(kind));

					// 不变式：`EdgePanelLayout` 的**平行数组长度必须全部等于行数**。
					// 这 13 个按行平行的 vector 每个分支都要按同一顺序 push 恰好 13 项，
					// 漏一项就会让某一列读到别的行的矩形（"改布局就出错"的典型机制）。
					// ⚠️ 「重采样」专属的 4 个数组（最大/最小间隔、间隔/频率输入框）在**其它**
					//    面板里允许为空（没人读），但只要非空就必须同样与行数对齐。
					// 成本极低（O(1) 比长度），但能挡住整类错位缺陷。
					const std::size_t rowCount = layout.rowRefs.size();
					const std::size_t coreSizes[] = {
					    layout.rowRefs.size(),        layout.rowHeaders.size(),
					    layout.rowNameRects.size(),   layout.rowTriangles.size(),
					    layout.rowChecks.size(),      layout.rowPoints.size(),
					    layout.rowIterations.size(),  layout.rowStats.size(),
					    layout.rowLevelTracks.size(), layout.rowLevelValues.size(),
					    layout.rowLevelResets.size(), layout.rowIterTracks.size(),
					    layout.rowIterValues.size(),  layout.rowIterResets.size()};
					bool parallel = true;
					for (const std::size_t size : coreSizes)
					{
						if (size != rowCount)
						{
							parallel = false;
							break;
						}
					}
					const std::size_t resampleSizes[] = {
					    layout.rowInfoMaxInterval.size(), layout.rowInfoMinInterval.size(),
					    layout.rowIntervalField.size(),   layout.rowFrequencyField.size()};
					bool resampleParallel = true;
					for (const std::size_t size : resampleSizes)
					{
						if (size != 0 && size != rowCount)
						{
							resampleParallel = false;
							break;
						}
					}
					if (!parallel || !resampleParallel)
					{
						EmitLine("[panels] %s row arrays: refs=%d hdr=%d name=%d tri=%d chk=%d pts=%d it=%d "
						         "stat=%d lvl=%d/%d/%d iter=%d/%d/%d info=%d/%d fld=%d/%d\n",
						         PanelKindName(kind), static_cast<int>(layout.rowRefs.size()),
						         static_cast<int>(layout.rowHeaders.size()),
						         static_cast<int>(layout.rowNameRects.size()),
						         static_cast<int>(layout.rowTriangles.size()),
						         static_cast<int>(layout.rowChecks.size()),
						         static_cast<int>(layout.rowPoints.size()),
						         static_cast<int>(layout.rowIterations.size()),
						         static_cast<int>(layout.rowStats.size()),
						         static_cast<int>(layout.rowLevelTracks.size()),
						         static_cast<int>(layout.rowLevelValues.size()),
						         static_cast<int>(layout.rowLevelResets.size()),
						         static_cast<int>(layout.rowIterTracks.size()),
						         static_cast<int>(layout.rowIterValues.size()),
						         static_cast<int>(layout.rowIterResets.size()),
						         static_cast<int>(layout.rowInfoMaxInterval.size()),
						         static_cast<int>(layout.rowInfoMinInterval.size()),
						         static_cast<int>(layout.rowIntervalField.size()),
						         static_cast<int>(layout.rowFrequencyField.size()));
					}
					Expect(parallel, std::string("row arrays have identical lengths: ") + PanelKindName(kind));
					Expect(resampleParallel,
					       std::string("resample row arrays empty-or-aligned: ") + PanelKindName(kind));

					char buffer[160] = {};
					std::snprintf(buffer, sizeof(buffer), "%s=%016llX,%d,%d,%d,%d\n", PanelKindName(kind),
					              static_cast<unsigned long long>(HashRegion(session.LastFrame(), rect)), rect.x,
					              rect.y, rect.width, rect.height);
					content += buffer;
				}

				const std::string baselinePath = Join(options.outDir, "panels-baseline.txt");
				if (options.mode == "record")
				{
					Expect(WriteTextFile(baselinePath, content), "write panels baseline");
					EmitLine("[panels] baseline recorded: %s\n", baselinePath.c_str());
				}
				else if (options.mode == "compare")
				{
					const std::string baseline = ReadTextFile(baselinePath);
					Expect(!baseline.empty(), "panels baseline exists (run -mode record first)");
					const std::vector<std::pair<std::string, std::string>> entries = ParseBaseline(baseline);
					const std::vector<std::pair<std::string, std::string>> current = ParseBaseline(content);
					ExpectEqual(static_cast<long long>(current.size()), static_cast<long long>(entries.size()),
					            "panel count matches baseline");
					for (const auto& expected : entries)
					{
						bool found = false;
						for (const auto& actual : current)
						{
							if (actual.first != expected.first)
							{
								continue;
							}
							found = true;
							if (actual.second != expected.second)
							{
								EmitLine("[panels] MISMATCH %s: baseline=%s current=%s\n", expected.first.c_str(),
								         expected.second.c_str(), actual.second.c_str());
								Expect(false, std::string("panel pixel hash unchanged: ") + expected.first);
							}
							break;
						}
						if (!found)
						{
							Expect(false, std::string("panel present in baseline: ") + expected.first);
						}
					}
					EmitLine("[panels] compare done against %s\n", baselinePath.c_str());
				}
				else
				{
					// verify：没有基线也要守住"几何不变式"，并把当前哈希打出来便于人工比对
					EmitLine("[panels] (hint) use -mode record / -mode compare for pixel A/B\n");
				}

				if (options.savePng)
				{
					Expect(SavePng(session.LastFrame(), Join(options.outDir, "panels.png")),
					       "save panels.png");
				}
				return CheckFailed();
			}

			/**
			 * @brief 面板**内容滚动**的行为检查（每一类面板都要能被滚动，且几何随之一致移动）。
			 *
			 * 为什么单独一项：面板滚动量过去由 7 个近乎重复的设置函数 + 2 条按种类分派的
			 * `switch`/`if` 链共同维护，历史上出现过"滚轮能滚、拖滚动条滚不动"与
			 * "读的是 A 面板的偏移、写进了 B 面板"。本检查对 7 种面板逐一：
			 *  1. 取布局 → 若可滚动，记录初始 `scrollOffset`；
			 *  2. 通过**统一入口** `SetLanePanelScroll` 滚到底；
			 *  3. 断言 `scrollOffset` 等于 `maxScroll`、滑块位置真的移到了轨道底部；
			 *  4. 再滚回顶部，断言滑块回到轨道顶部。
			 */
			int CheckPanelScroll(Session& session, const CheckOptions& options)
			{
				Application& app = session.App();
				PlotView& plot = app.m_plot;

				// 让面板内容**必定超高**：显示全部信号并合并成一个网格
				//（真实场景见历史缺陷：283 条信号合并到同一网格、开实验性功能）。
				int totalSignals = 0;
				for (int groupIndex = 0; groupIndex < static_cast<int>(app.m_dataSet.GroupCount()); ++groupIndex)
				{
					const SignalGroup* group = app.m_dataSet.GroupAt(groupIndex);
					if (group != nullptr)
					{
						totalSignals += static_cast<int>(group->signals.size());
					}
				}
				session.ShowFirstSignals(0);
				if (session.LaneCount() > 1)
				{
					app.ExecuteToolbarAction(ToolbarAction::MERGE_LANES);
				}
				EmitLine("[panelscroll] signals=%d lanes=%d\n", totalSignals, session.LaneCount());
				Expect(totalSignals > 0, "loaded at least one signal");

				if (app.ActiveTab().CursorMode() != PlotCursorMode::DOUBLE)
				{
					for (int step = 0; step < 4 && app.ActiveTab().CursorMode() != PlotCursorMode::DOUBLE; ++step)
					{
						plot.CycleCursorMode();
					}
				}

				static const EdgePanelKind kinds[] = {EdgePanelKind::COUNT,   EdgePanelKind::CENTER,
				                                      EdgePanelKind::MEAN,    EdgePanelKind::PEAK,
				                                      EdgePanelKind::MARK,    EdgePanelKind::RESAMPLE,
				                                      EdgePanelKind::CLIP};
				for (const EdgePanelKind kind : kinds)
				{
					EnsureLaneFeature(plot, 0, kind);
				}
				session.RenderFrame();

				int scrollableKinds = 0;
				for (const EdgePanelKind kind : kinds)
				{
					const char* name = PanelKindName(kind);
					const PlotView::EdgePanelLayout initial = plot.EdgePanelLayoutFor(0, kind);
					const float maxScroll =
					    std::max(0.0f, initial.markerContentHeight - initial.content.Height);
					EmitLine("[panelscroll] %-8s content=%.1f view=%.1f maxScroll=%.1f scrollable=%d rows=%d\n",
					         name, initial.markerContentHeight, initial.content.Height, maxScroll,
					         initial.scrollTrack.Width > 0.0f ? 1 : 0,
					         static_cast<int>(initial.rowRefs.size()));

					// 多信号场景下额外守住"平行数组长度一致"（本轮新增，成本 O(1)）。
					{
						const std::size_t rows = initial.rowRefs.size();
						const std::size_t sizes[] = {initial.rowHeaders.size(),      initial.rowNameRects.size(),
						                             initial.rowTriangles.size(),    initial.rowChecks.size(),
						                             initial.rowPoints.size(),       initial.rowIterations.size(),
						                             initial.rowStats.size(),        initial.rowLevelTracks.size(),
						                             initial.rowLevelValues.size(),  initial.rowLevelResets.size(),
						                             initial.rowIterTracks.size(),   initial.rowIterValues.size(),
						                             initial.rowIterResets.size(),   initial.rowInfoMaxInterval.size(),
						                             initial.rowInfoMinInterval.size(),
						                             initial.rowIntervalField.size(),
						                             initial.rowFrequencyField.size()};
						bool aligned = true;
						for (const std::size_t size : sizes)
						{
							// 「重采样」专属数组在其它面板允许为空（见 `panels` 检查的说明）。
							if (size != rows && size != 0)
							{
								aligned = false;
								break;
							}
						}
						Expect(aligned, std::string("row arrays aligned with rows: ") + name);
					}

					if (maxScroll <= 1.0f)
					{
						// 内容没超出可视高度（例如单信号文件）：不可滚动是正确行为。
						Expect(initial.scrollTrack.Width <= 0.0f,
						       std::string("no scrollbar when content fits: ") + name);
						ExpectNear(initial.scrollOffset, 0.0, 0.5,
						           std::string("scroll offset stays 0: ") + name);
						continue;
					}
					++scrollableKinds;

					Expect(initial.scrollTrack.Width > 0.0f,
					       std::string("scrollbar appears when content overflows: ") + name);

					// 滚到底
					Expect(plot.SetLanePanelScroll(0, kind, maxScroll + 500.0f),
					       std::string("set scroll to bottom: ") + name);
					const PlotView::EdgePanelLayout bottom = plot.EdgePanelLayoutFor(0, kind);
					ExpectNear(bottom.scrollOffset, maxScroll, 0.5,
					           std::string("scroll offset clamps to maxScroll: ") + name);
					const float travel = initial.scrollTrack.Height - initial.scrollThumb.Height;
					ExpectNear(bottom.scrollThumb.Y, initial.scrollTrack.Y + travel, 1.0,
					           std::string("thumb reaches track bottom: ") + name);
					// 内容区几何不能随滚动改变
					ExpectNear(bottom.content.Y, initial.content.Y, 0.01,
					           std::string("content area stays put when scrolling: ") + name);

					// 滚回顶部
					Expect(plot.SetLanePanelScroll(0, kind, -100.0f),
					       std::string("set scroll back to top: ") + name);
					const PlotView::EdgePanelLayout top = plot.EdgePanelLayoutFor(0, kind);
					ExpectNear(top.scrollOffset, 0.0, 0.5, std::string("scroll offset back to 0: ") + name);
					ExpectNear(top.scrollThumb.Y, initial.scrollTrack.Y, 1.0,
					           std::string("thumb back to track top: ") + name);
				}

				EmitLine("[panelscroll] scrollable kinds: %d / %d\n", scrollableKinds,
				         static_cast<int>(sizeof(kinds) / sizeof(kinds[0])));
				// 用大文件（如 MF4-Record.MF4，283 信号）时必须至少有一类面板真的能滚：
				// 否则这条检查会退化成"全是 0 == 0"的空转。
				if (totalSignals >= 50)
				{
					Expect(scrollableKinds > 0, "with many signals at least one panel is scrollable");
				}

				session.RenderFrame();
				if (options.savePng)
				{
					Expect(SavePng(session.LastFrame(), Join(options.outDir, "panelscroll.png")),
					       "save panelscroll.png");
				}
				return CheckFailed();
			}

			int CheckEdgeStats(Session& session, const CheckOptions& options)
			{
				session.ShowFirstSignals(1);
				Expect(session.LaneCount() >= 1, "one lane");

				const Application& app = session.App();
				SignalRef ref{0, 0};
				const DataSet& dataSet = app.m_dataSet;
				const SignalGroup* group = dataSet.GroupAt(0);
				Expect(group != nullptr && !group->signals.empty(), "group has signals");
				if (group == nullptr || group->signals.empty())
				{
					return CheckFailed();
				}

				// 挑一条"最有起伏"的信号：常量信号（只有 1 个不同取值）上任何阈值都得不到边沿，
				// 断言会退化成"0 == 0"的空转（MF4 的第一条信号就是常量）。
				const SignalData* chosen = nullptr;
				double chosenSpan = -1.0;
				for (const SignalData& candidate : group->signals)
				{
					double low = 0.0;
					double high = 1.0;
					FiniteRange(candidate.values, low, high);
					const double span = high - low;
					if (candidate.values.size() >= 4 && span > chosenSpan)
					{
						chosen = &candidate;
						chosenSpan = span;
					}
				}
				Expect(chosen != nullptr && chosenSpan > 0.0, "found a non-constant signal");
				if (chosen == nullptr || !(chosenSpan > 0.0))
				{
					return CheckFailed();
				}
				const SignalData& signal = *chosen;
				const TimeAxis& axis = group->AxisOf(signal);
				const SignalStyle& style = signal.style;

				double low = 0.0;
				double high = 1.0;
				FiniteRange(signal.values, low, high);
				EmitLine("[edgestats] signal=%d samples min=%.6g max=%.6g\n",
				         static_cast<int>(signal.values.size()), low, high);

				const double thresholds[] = {low + (high - low) * 0.25, (low + high) * 0.5,
				                             low + (high - low) * 0.75};
				for (const double threshold : thresholds)
				{
					std::size_t rising = 0;
					std::size_t falling = 0;
					int framesUsed = 0;
					const bool complete = CollectEdgeCounts(session, axis, signal, style, threshold, rising,
					                                        falling, framesUsed);
					Expect(complete, "edge scan completes");

					std::size_t expectedRising = 0;
					std::size_t expectedFalling = 0;
					ReferenceEdgeCounts(signal.values, style, threshold, expectedRising, expectedFalling);

					EmitLine("[edgestats] threshold=%.6g frames=%d got=(%llu,%llu) expected=(%llu,%llu)\n",
					         threshold, framesUsed, static_cast<unsigned long long>(rising),
					         static_cast<unsigned long long>(falling),
					         static_cast<unsigned long long>(expectedRising),
					         static_cast<unsigned long long>(expectedFalling));

					ExpectEqual(static_cast<long long>(rising), static_cast<long long>(expectedRising),
					            "rising edge count matches reference");
					ExpectEqual(static_cast<long long>(falling), static_cast<long long>(expectedFalling),
					            "falling edge count matches reference");

					// 缓存稳定性：同参数再查一次必须给出同一份完整结果
					std::size_t againRising = 0;
					std::size_t againFalling = 0;
					bool againComplete = false;
					app.m_plot.EdgeCountsFor(axis, signal, style, threshold, false, 0.0, 0.0, againRising,
					                         againFalling, againComplete);
					Expect(againComplete, "repeat query completes immediately");
					ExpectEqual(static_cast<long long>(againRising), static_cast<long long>(rising),
					            "repeat query rising stable");
					ExpectEqual(static_cast<long long>(againFalling), static_cast<long long>(falling),
					            "repeat query falling stable");
				}

				// 中心轴统计：只验证"能完成且结果稳定"（独立参考实现需要复刻窗口语义，
				// 收益不大；普通计数已覆盖 `EdgeScanFor` 的共享状态机）
				{
					std::size_t rising = 0;
					std::size_t falling = 0;
					bool complete = false;
					int guard = 0;
					while (!complete && guard < 4000)
					{
						app.m_plot.EdgeCenterCountsFor(axis, signal, style, 5, 1, false, 0.0, 0.0, rising,
						                              falling, complete);
						if (complete)
						{
							break;
						}
						session.RenderFrame();
						++guard;
					}
					Expect(complete, "centre edge scan completes");
					EmitLine("[edgestats] centre (points=5,iterations=1) rising=%llu falling=%llu frames=%d\n",
					         static_cast<unsigned long long>(rising),
					         static_cast<unsigned long long>(falling), guard);
					(void)ref;
				}
				return CheckFailed();
			}

			int CheckPerf(Session& session, const CheckOptions& options)
			{
				session.ShowFirstSignals(8);
				Expect(session.RenderFrame(), "warm-up render");

				// 1) 整帧渲染耗时（取 7 帧中位数，第一帧可能是预热）
				std::vector<double> renderTimes;
				for (int iteration = 0; iteration < 7; ++iteration)
				{
					if (!session.RenderFrame())
					{
						Expect(false, "render frame");
						break;
					}
					renderTimes.push_back(session.LastRenderMs());
				}
				std::sort(renderTimes.begin(), renderTimes.end());
				const double medianRender =
				    renderTimes.empty() ? 0.0 : renderTimes[renderTimes.size() / 2];
				EmitLine("[perf] render median=%.2fms lanes=%d\n", medianRender, session.LaneCount());
				Expect(medianRender < 500.0, "full frame below 500ms");

				// 2) 面板几何：`EdgePanelLayoutFor` 在鼠标移动的高频路径上，必须是"微秒级"
				Application& app = session.App();
				PlotView& plot = app.m_plot;
				static const EdgePanelKind kinds[] = {EdgePanelKind::COUNT, EdgePanelKind::CENTER,
				                                      EdgePanelKind::MEAN,  EdgePanelKind::PEAK,
				                                      EdgePanelKind::MARK,  EdgePanelKind::RESAMPLE,
				                                      EdgePanelKind::CLIP};
				for (const EdgePanelKind kind : kinds)
				{
					EnsureLaneFeature(plot, 0, kind);
				}
				session.RenderFrame();

				const int iterations = 2000;
				double totalMicroseconds = 0.0;
				LARGE_INTEGER frequency = {};
				LARGE_INTEGER start = {};
				LARGE_INTEGER stop = {};
				QueryPerformanceFrequency(&frequency);
				QueryPerformanceCounter(&start);
				float sink = 0.0f;
				for (int iteration = 0; iteration < iterations; ++iteration)
				{
					for (const EdgePanelKind kind : kinds)
					{
						const PlotView::EdgePanelLayout layout = plot.EdgePanelLayoutFor(0, kind);
						sink += layout.panel.Width + layout.title.Height;
					}
				}
				QueryPerformanceCounter(&stop);
				totalMicroseconds = static_cast<double>(stop.QuadPart - start.QuadPart) * 1000000.0 /
				                    static_cast<double>(frequency.QuadPart);
				const double perCall =
				    totalMicroseconds / static_cast<double>(iterations * static_cast<int>(sizeof(kinds) / sizeof(kinds[0])));
				EmitLine("[perf] EdgePanelLayoutFor: %.3f us/call (x%d calls) sink=%.1f\n", perCall,
				         iterations * static_cast<int>(sizeof(kinds) / sizeof(kinds[0])), sink);
				Expect(perCall < 200.0, "panel layout below 200us per call");

				// 3) 边沿统计查询：**多信号**时的"状态查找"成本
				//    （第 33 轮报告建议把 `m_edgeScans` 的线性扫描改哈希索引，改的就是这条路径）
				const DataSet& dataSet = app.m_dataSet;
				struct QueryTarget
				{
					const SignalData* signal = nullptr;
					const TimeAxis* axis = nullptr;
					double threshold = 0.0;
				};
				std::vector<QueryTarget> targets;
				for (int groupIndex = 0; groupIndex < static_cast<int>(dataSet.GroupCount()); ++groupIndex)
				{
					const SignalGroup* group = dataSet.GroupAt(groupIndex);
					if (group == nullptr)
					{
						continue;
					}
					for (const SignalData& signal : group->signals)
					{
						if (signal.values.size() < 2)
						{
							continue;
						}
						double low = 0.0;
						double high = 1.0;
						FiniteRange(signal.values, low, high);
						QueryTarget target;
						target.signal = &signal;
						target.axis = &group->AxisOf(signal);
						target.threshold = (low + high) * 0.5;
						targets.push_back(target);
						if (targets.size() >= 200)
						{
							break;
						}
					}
					if (targets.size() >= 200)
					{
						break;
					}
				}

				if (!targets.empty())
				{
					// 预热：把所有累积状态都建起来并扫完（否则测到的是"扫描成本"而不是"查找成本"）
					for (int guard = 0; guard < 400; ++guard)
					{
						bool allComplete = true;
						for (const QueryTarget& target : targets)
						{
							std::size_t r = 0;
							std::size_t f = 0;
							bool complete = false;
							plot.EdgeCountsFor(*target.axis, *target.signal, target.signal->style,
							                    target.threshold, false, 0.0, 0.0, r, f, complete);
							if (!complete)
							{
								allComplete = false;
							}
						}
						if (allComplete)
						{
							break;
						}
						session.RenderFrame();
					}
					EmitLine("[perf] edge states=%d targets=%d\n", static_cast<int>(plot.m_edgeScans.size()),
					         static_cast<int>(targets.size()));

					const int rounds = 20;
					QueryPerformanceCounter(&start);
					for (int round = 0; round < rounds; ++round)
					{
						for (const QueryTarget& target : targets)
						{
							std::size_t r = 0;
							std::size_t f = 0;
							bool complete = false;
							plot.EdgeCountsFor(*target.axis, *target.signal, target.signal->style,
							                    target.threshold, false, 0.0, 0.0, r, f, complete);
							sink += static_cast<float>(r + f);
						}
					}
					QueryPerformanceCounter(&stop);
					const double total = static_cast<double>(stop.QuadPart - start.QuadPart) * 1000000.0 /
					                     static_cast<double>(frequency.QuadPart);
					const double perQuery = total / (static_cast<double>(rounds) *
					                                 static_cast<double>(targets.size()));
					EmitLine("[perf] EdgeCountsFor sweep: %.3f us/query (%d targets x %d rounds) sink=%.1f\n",
					         perQuery, static_cast<int>(targets.size()), rounds, sink);
					Expect(perQuery < 20.0, "edge count query below 20us with 200 states");
				}

				if (options.savePng)
				{
					Expect(SavePng(session.LastFrame(), Join(options.outDir, "perf.png")), "save perf.png");
				}
				return CheckFailed();
			}
		} // namespace

		const std::vector<CheckDescriptor>& AvailableChecks()
		{
			static const std::vector<CheckDescriptor> checks = {
			    {"smoke", "offscreen init + load + render + determinism + save png", CheckSmoke},
			    {"frames", "capture consecutive frames while moving mouse (png + hash + timing)", CheckFrames},
			    {"panels", "all 7 experiment panels: geometry invariants + pixel baseline A/B", CheckPanels},
			    {"panelscroll", "panel content scrolling: every kind scrolls, clamps, and keeps content fixed",
			     CheckPanelScroll},
			    {"edgestats", "edge counts vs independent reference implementation", CheckEdgeStats},
			    {"perf", "render / panel layout / edge query timings", CheckPerf},
			};
			return checks;
		}

		const CheckDescriptor* FindCheck(const std::string& name)
		{
			for (const CheckDescriptor& descriptor : AvailableChecks())
			{
				if (name == descriptor.name)
				{
					return &descriptor;
				}
			}
			return nullptr;
		}

		int& CheckTotal()
		{
			static int total = 0;
			return total;
		}

		int& CheckFailed()
		{
			static int failed = 0;
			return failed;
		}

		void Expect(const bool ok, const std::string& what)
		{
			++CheckTotal();
			if (!ok)
			{
				++CheckFailed();
				EmitLine("  [FAIL] %s\n", what.c_str());
			}
		}

		void ExpectEqual(const long long actual, const long long expected, const std::string& what)
		{
			++CheckTotal();
			if (actual != expected)
			{
				++CheckFailed();
				EmitLine("  [FAIL] %s: actual=%lld expected=%lld\n", what.c_str(), actual, expected);
			}
		}

		void ExpectNear(const double actual, const double expected, const double tolerance,
		                const std::string& what)
		{
			const double delta = (actual > expected) ? (actual - expected) : (expected - actual);
			++CheckTotal();
			if (!(delta <= tolerance))
			{
				++CheckFailed();
				EmitLine("  [FAIL] %s: actual=%.17g expected=%.17g\n", what.c_str(), actual, expected);
			}
		}

		std::string ReadTextFile(const std::string& path)
		{
			const std::wstring wide = Widen(path);
			if (wide.empty())
			{
				return std::string();
			}
			HANDLE handle = CreateFileW(wide.c_str(), GENERIC_READ, FILE_SHARE_READ, nullptr, OPEN_EXISTING,
			                            FILE_ATTRIBUTE_NORMAL, nullptr);
			if (handle == INVALID_HANDLE_VALUE)
			{
				return std::string();
			}
			LARGE_INTEGER size = {};
			if (!GetFileSizeEx(handle, &size) || size.QuadPart <= 0 || size.QuadPart > (1ll << 26))
			{
				CloseHandle(handle);
				return std::string();
			}
			std::string content(static_cast<std::size_t>(size.QuadPart), '\0');
			DWORD read = 0;
			const BOOL ok = ReadFile(handle, &content[0], static_cast<DWORD>(content.size()), &read, nullptr);
			CloseHandle(handle);
			if (!ok)
			{
				return std::string();
			}
			content.resize(read);
			return content;
		}

		bool WriteTextFile(const std::string& path, const std::string& content)
		{
			EnsureDirectory(DirectoryOf(path));
			const std::wstring wide = Widen(path);
			if (wide.empty())
			{
				return false;
			}
			HANDLE handle = CreateFileW(wide.c_str(), GENERIC_WRITE, 0, nullptr, CREATE_ALWAYS,
			                            FILE_ATTRIBUTE_NORMAL, nullptr);
			if (handle == INVALID_HANDLE_VALUE)
			{
				return false;
			}
			DWORD written = 0;
			const BOOL ok = WriteFile(handle, content.data(), static_cast<DWORD>(content.size()), &written,
			                          nullptr);
			CloseHandle(handle);
			return ok != FALSE && written == content.size();
		}
	} // namespace tools
} // namespace jdi