#include "TabBar.hpp"

#include "UiControls.hpp"
#include <algorithm>
#include <cmath>
#include <functional>

#include "UiDebugBounds.hpp"
#include "Utf8Util.hpp"

namespace jdi
{

	namespace
	{
		const float kTabHeight = 32.0f;			/**< 标签高度（逻辑像素）。 */
		const float kTopMargin = 4.0f;			/**< 标签顶部留白。 */
		const float kLeftPadding = 8.0f;		/**< 左侧留白。 */
		const float kTabPadding = 14.0f;		/**< 标签文本左右内边距。 */
		const float kCloseSize = 16.0f;			/**< 关闭按钮尺寸。 */
		const float kCloseGap = 6.0f;			/**< 文本与关闭按钮间距。 */
		const float kAddSize = 24.0f;			/**< 新建按钮尺寸。 */
		const float kAddGap = 6.0f;				/**< 新建按钮与末个标签的间距。 */
		const float kCorner = 5.0f;				/**< 标签圆角半径。 */
		const float kMaxTabWidth = 200.0f;		/**< 单个标签最大宽度（逻辑像素）。 */
		const float kEditingTabWidth = 320.0f;	/**< 重命名输入时标签的最大宽度（便于看清长名称）。 */
		const float kMinTabWidth = 70.0f;		/**< 单个标签最小宽度（逻辑像素）。 */

		/**
		 * @brief 单个标签页控件：只负责"把这一格画出来"。
		 *
		 * 手势语义（自行判双击 / 拖拽排序 / 关闭 ✕ 的"移开取消"）仍留在 `TabBar` 里 ——
		 * 那些是多年补丁叠出的隐式约定，迁移控件时**不能顺手重写**。
		 */
		class TabItemWidget : public UiWidget
		{
		public:
			void Configure(const UiFonts* fonts, const Theme* theme, float scale)
			{
				m_fonts = fonts;
				m_theme = theme;
				m_scale = scale;
			}

			/** @brief 更新这一格的显示状态（名称 / 激活 / 编辑态 / 关闭按钮几何）。 */
			void SetState(std::wstring name, bool active, gd::RectF closeRect, bool editing,
			              const TextEdit* edit, gd::RectF editRect)
			{
				const bool changed = (m_name != name) || (m_active != active) || (m_editing != editing);
				m_name = std::move(name);
				m_active = active;
				m_closeRect = closeRect;
				m_editing = editing;
				m_edit = edit;
				m_editRect = editRect;
				if (changed)
				{
					Invalidate(Bounds());
				}
				else
				{
					// 几何/编辑框位置变化也要重画（重命名时标签会随输入变宽）。
					Invalidate(Bounds());
				}
			}

			/** @brief 关闭按钮矩形（`TabBar` 用于手势命中；绘制与命中同源）。 */
			const gd::RectF& CloseRect() const { return m_closeRect; }

			gd::SizeF OnMeasure(const UiMeasureContext& ctx) override
			{
				(void)ctx;
				return gd::SizeF(Bounds().Width, Bounds().Height);
			}

			void OnPaint(UiPaintContext& ctx) override
			{
				if (m_theme == nullptr || m_fonts == nullptr || ctx.g == nullptr)
				{
					return;
				}
				const gd::RectF& rect = Bounds();
				int hoverX = 0;
				int hoverY = 0;
				const bool hovered = HoverPoint(hoverX, hoverY);
				const bool closeHot =
				    hovered && UiPointInRect(m_closeRect, static_cast<float>(hoverX),
				                             static_cast<float>(hoverY));

				std::uint32_t background = m_theme->panelBg;
				if (m_active)
				{
					background = m_theme->cardBg;
				}
				else if (hovered)
				{
					background = m_theme->hover;
				}
				UiFillRoundRect(*ctx.g, rect, kCorner * m_scale, background);

				if (!m_active)
				{
					UiDrawRoundRect(*ctx.g, rect, kCorner * m_scale, m_theme->border, 1.0f);
				}
				else
				{
					// 激活页使用顶部强调条指示。
					UiFillRoundRect(*ctx.g,
					                gd::RectF(rect.X + kCorner * m_scale, rect.Y,
					                          rect.Width - kCorner * 2.0f * m_scale, 2.5f * m_scale),
					                1.0f * m_scale, m_theme->accent);
				}

				const float textLeft = rect.X + kTabPadding * m_scale;
				const float textWidth = m_closeRect.X - kCloseGap * m_scale - textLeft;

				if (m_editing && m_edit != nullptr)
				{
					// 重命名编辑态：在标签本体之上叠加输入框（标签底色与边框仍然保留）。
					UiDrawEditField(*ctx.g, m_editRect, *m_edit, m_fonts->ui, m_scale);
				}
				else
				{
					const std::wstring label =
					    UiEllipsize(m_name, m_fonts->ui, std::max(8.0f, textWidth));
					UiText(*ctx.g, label, m_active ? m_fonts->uiBold : m_fonts->ui,
					       gd::RectF(textLeft, rect.Y, std::max(8.0f, textWidth), rect.Height),
					       m_active ? m_theme->textStrong : m_theme->text, TextAlign::LEFT);
				}

				// 关闭按钮：悬停时显示底色，图标始终可见。
				const float closeIconSize = 8.0f * m_scale;
				if (closeHot)
				{
					UiFillRoundRect(*ctx.g, m_closeRect, 3.0f * m_scale, m_theme->pressed);
				}
				const float cx = m_closeRect.X + m_closeRect.Width * 0.5f;
				const float cy = m_closeRect.Y + m_closeRect.Height * 0.5f;
				const std::uint32_t iconColor = closeHot
				                                    ? m_theme->danger
				                                    : (m_active ? m_theme->text : m_theme->textMuted);
				UiDrawLine(*ctx.g, cx - closeIconSize * 0.5f, cy - closeIconSize * 0.5f,
				           cx + closeIconSize * 0.5f, cy + closeIconSize * 0.5f, iconColor,
				           1.4f * m_scale);
				UiDrawLine(*ctx.g, cx + closeIconSize * 0.5f, cy - closeIconSize * 0.5f,
				           cx - closeIconSize * 0.5f, cy + closeIconSize * 0.5f, iconColor,
				           1.4f * m_scale);
			}

		private:
			const UiFonts* m_fonts = nullptr;		/**< 字体。 */
			const Theme* m_theme = nullptr;			/**< 主题。 */
			float m_scale = 1.0f;					/**< 缩放系数。 */
			std::wstring m_name;					/**< 标签名称。 */
			bool m_active = false;					/**< 是否激活。 */
			bool m_editing = false;					/**< 是否处于重命名编辑态。 */
			const TextEdit* m_edit = nullptr;		/**< 编辑模型（编辑态时非空）。 */
			gd::RectF m_editRect;					/**< 编辑框矩形。 */
			gd::RectF m_closeRect;					/**< 关闭按钮矩形。 */
		};

		/** @brief 「+」新建按钮控件。 */
		class TabAddWidget : public UiWidget
		{
		public:
			void Configure(const UiFonts* fonts, const Theme* theme, float scale)
			{
				m_fonts = fonts;
				m_theme = theme;
				m_scale = scale;
			}

			gd::SizeF OnMeasure(const UiMeasureContext& ctx) override
			{
				(void)ctx;
				return gd::SizeF(Bounds().Width, Bounds().Height);
			}

			void OnPaint(UiPaintContext& ctx) override
			{
				if (m_theme == nullptr || ctx.g == nullptr)
				{
					return;
				}
				const gd::RectF& rect = Bounds();
				const bool hovered = Hovered();
				const std::uint32_t addBg = hovered ? m_theme->hover : m_theme->panelBg;
				UiFillRoundRect(*ctx.g, rect, kCorner * m_scale, addBg);
				UiDrawRoundRect(*ctx.g, rect, kCorner * m_scale, m_theme->border, 1.0f);

				const float ax = rect.X + rect.Width * 0.5f;
				const float ay = rect.Y + rect.Height * 0.5f;
				const float armLength = 4.5f * m_scale;
				const std::uint32_t addColor = hovered ? m_theme->accent : m_theme->text;
				UiDrawLine(*ctx.g, ax - armLength, ay, ax + armLength, ay, addColor, 1.6f * m_scale);
				UiDrawLine(*ctx.g, ax, ay - armLength, ax, ay + armLength, addColor, 1.6f * m_scale);
			}

		private:
			const UiFonts* m_fonts = nullptr;		/**< 字体（当前未使用，保留给将来的图标）。 */
			const Theme* m_theme = nullptr;			/**< 主题。 */
			float m_scale = 1.0f;					/**< 缩放系数。 */
		};

		/**
		 * @brief 覆盖层控件：画"拖拽插入指示条 + 底部分隔线"。
		 *
		 * 它必须**最后绘制**（在标签与「+」之后），因此作为根节点的最后一个子节点，
		 * 且**命中透明**（纯装饰，不参与命中与光标链）。
		 */
		class TabOverlayWidget : public UiWidget
		{
		public:
			gd::SizeF OnMeasure(const UiMeasureContext& ctx) override
			{
				(void)ctx;
				return gd::SizeF(Bounds().Width, Bounds().Height);
			}

			void OnPaint(UiPaintContext& ctx) override
			{
				if (ctx.g == nullptr)
				{
					return;
				}
				if (paintOverlay)
				{
					paintOverlay(*ctx.g, Bounds());
				}
			}

			/** @brief 由 `TabBar` 注入的覆盖层绘制回调（拖拽指示条 + 分隔线）。 */
			std::function<void(gd::Graphics&, const gd::RectF&)> paintOverlay;
		};

		/** @brief 标签栏根：只负责底色（其余交给子节点按 z 序绘制）。 */
		class TabRootWidget : public UiWidget
		{
		public:
			void Configure(const Theme* theme)
			{
				m_theme = theme;
			}

			gd::SizeF OnMeasure(const UiMeasureContext& ctx) override
			{
				(void)ctx;
				return gd::SizeF(Bounds().Width, Bounds().Height);
			}

			void OnPaint(UiPaintContext& ctx) override
			{
				if (m_theme == nullptr || ctx.g == nullptr || !UiRectHasArea(Bounds()))
				{
					return;
				}
				UiFillRect(*ctx.g, Bounds(), m_theme->panelBg);
			}

		private:
			const Theme* m_theme = nullptr;		/**< 主题。 */
		};

	} // namespace

	TabBar::TabBar() = default;

	// 控件树用 `std::unique_ptr<UiWidget>` 持有，而具体根类型只在本 TU 可见
	// ⇒ 析构函数必须在这里显式定义。
	TabBar::~TabBar() = default;

	void TabBar::Setup(const UiFonts* fonts, const Theme* theme)
	{
		m_fonts = fonts;
		m_theme = theme;
	}

	void TabBar::SetScale(float scale)
	{
		m_scale = (scale > 0.1f) ? scale : 1.0f;
	}

	void TabBar::SetTabs(const std::vector<std::wstring>& names)
	{
		m_tabs.clear();
		m_tabs.resize(names.size());
		for (std::size_t index = 0; index < names.size(); ++index)
		{
			m_tabs[index].name = names[index];
		}
		if (m_activeIndex >= static_cast<int>(m_tabs.size()))
		{
			m_activeIndex = m_tabs.empty() ? -1 : static_cast<int>(m_tabs.size()) - 1;
		}
		// 标签数量变化 ⇒ 重建控件树（旧控件里缓存的几何与名称全部作废）。
		RebuildWidgets();
	}

	void TabBar::SetActiveIndex(int index)
	{
		if (m_activeIndex == index)
		{
			return;
		}
		m_activeIndex = index;
		ArrangeWidgets();
	}

	float TabBar::DesiredHeight() const
	{
		return (kTabHeight + kTopMargin) * m_scale;
	}

	void TabBar::RebuildWidgets()
	{
		m_root = std::make_unique<TabRootWidget>();
		static_cast<TabRootWidget*>(m_root.get())->Configure(m_theme);

		for (std::size_t index = 0; index < m_tabs.size(); ++index)
		{
			auto widget = std::make_unique<TabItemWidget>();
			static_cast<TabItemWidget*>(widget.get())->Configure(m_fonts, m_theme, m_scale);
			m_root->AddChild(std::move(widget));
		}

		auto add = std::make_unique<TabAddWidget>();
		static_cast<TabAddWidget*>(add.get())->Configure(m_fonts, m_theme, m_scale);
		m_root->AddChild(std::move(add));

		auto overlay = std::make_unique<TabOverlayWidget>();
		TabOverlayWidget* overlayRaw = static_cast<TabOverlayWidget*>(overlay.get());
		overlayRaw->SetHitTransparent(true);
		overlayRaw->paintOverlay = [this](gd::Graphics& g, const gd::RectF& area)
		{
			// 拖拽排序时在插入位置绘制强调色指示条。
			if (m_dragIndex >= 0 && m_dragMoved && !m_tabs.empty() && m_theme != nullptr)
			{
				const int drop = DropIndexAt(m_dragMouseX);
				float markerX = m_addRect.X;
				if (drop < static_cast<int>(m_tabs.size()))
				{
					markerX = m_tabs[static_cast<std::size_t>(drop)].rect.X - kAddGap * m_scale * 0.5f;
				}
				const float top = area.Y + kTopMargin * m_scale;
				const float bottom = top + kTabHeight * m_scale;
				UiFillRoundRect(g,
				                gd::RectF(markerX - 1.5f * m_scale, top, 3.0f * m_scale, bottom - top),
				                1.5f * m_scale, m_theme->accent);
			}
			// 底部分隔线。
			if (m_theme != nullptr)
			{
				UiDrawLine(g, area.X, area.Y + area.Height - 1.0f, area.X + area.Width,
				           area.Y + area.Height - 1.0f, m_theme->border, 1.0f);
			}
		};
		m_root->AddChild(std::move(overlay));
	}

	void TabBar::Layout(const gd::RectF& area)
	{
		m_area = area;
		if (m_fonts == nullptr || m_fonts->ui == nullptr)
		{
			return;
		}
		if (m_root == nullptr)
		{
			RebuildWidgets();
		}

		const float tabHeight = kTabHeight * m_scale;
		const float top = area.Y + kTopMargin * m_scale;
		const float closeSize = kCloseSize * m_scale;
		const float minWidth = kMinTabWidth * m_scale;
		const float addSize = kAddSize * m_scale;

		// 标签宽度按「加粗字体」测量：激活页用 uiBold 绘制，
		// 若按常规字体测量，加粗后的长名称会在激活时被省略号截断（预览过短）。
		std::vector<float> desired;
		desired.reserve(m_tabs.size());
		float total = kLeftPadding * m_scale;
		for (std::size_t index = 0; index < m_tabs.size(); ++index)
		{
			const bool editing = (static_cast<int>(index) == m_editIndex);

			// 重命名过程中按「正在输入的文本」测量，标签才能随输入逐步变宽；
			// 否则始终按已提交的旧名称算宽度，长名称会被挤成很短的一截（预览过短）。
			const std::wstring& measureText = editing ? m_edit.Text() : m_tabs[index].name;
			const float boldWidth = UiMeasureTextWidth(m_fonts->uiBold, measureText);
			const float regularWidth = UiMeasureTextWidth(m_fonts->ui, measureText);
			const float textWidth = std::max(boldWidth, regularWidth);

			const float maxWidth = (editing ? kEditingTabWidth : kMaxTabWidth) * m_scale;

			float width = kTabPadding * 2.0f * m_scale + textWidth + kCloseGap * m_scale + closeSize;
			width = std::max(minWidth, std::min(width, maxWidth));
			desired.push_back(width);
			total += width + kAddGap * m_scale;
		}
		total += addSize;

		// 标签总宽超出可用宽度时整体等比收缩，保证「+」按钮始终可见。
		const float available = area.Width - kLeftPadding * m_scale;
		float shrink = 1.0f;
		if (total > available && total > 0.0f)
		{
			shrink = available / total;
		}

		float cursorX = area.X + kLeftPadding * m_scale;
		for (std::size_t index = 0; index < m_tabs.size(); ++index)
		{
			TabItem& tab = m_tabs[index];
			float width = std::max(minWidth * shrink, desired[index] * shrink);

			// 收缩后仍要保证「文本 + 关闭按钮」有最小可用空间。
			width = std::max(width, closeSize + kTabPadding * m_scale + 8.0f * m_scale);

			tab.rect = gd::RectF(cursorX, top, width, tabHeight);
			tab.closeRect = gd::RectF(cursorX + width - kTabPadding * m_scale - closeSize,
			                          top + (tabHeight - closeSize) * 0.5f, closeSize, closeSize);

			cursorX += width + kAddGap * m_scale;
		}

		m_addRect = gd::RectF(std::min(cursorX, area.X + area.Width - addSize - 2.0f * m_scale),
		                      top + (tabHeight - addSize) * 0.5f, addSize, addSize);

		ArrangeWidgets();
	}

	void TabBar::ArrangeWidgets()
	{
		if (m_root == nullptr || m_root->Children().size() != m_tabs.size() + 2)
		{
			RebuildWidgets();
		}
		if (m_root == nullptr)
		{
			return;
		}

		m_root->Arrange(m_area);
		const std::vector<std::unique_ptr<UiWidget>>& children = m_root->Children();
		for (std::size_t index = 0; index < m_tabs.size(); ++index)
		{
			TabItemWidget* widget = static_cast<TabItemWidget*>(children[index].get());
			const TabItem& tab = m_tabs[index];
			const bool editing = (static_cast<int>(index) == m_editIndex);
			widget->Arrange(tab.rect);
			widget->SetState(tab.name, static_cast<int>(index) == m_activeIndex, tab.closeRect, editing,
			                 editing ? &m_edit : nullptr, EditRect());
		}
		static_cast<TabAddWidget*>(children[m_tabs.size()].get())->Arrange(m_addRect);
		static_cast<TabOverlayWidget*>(children[m_tabs.size() + 1].get())->Arrange(m_area);
	}

	void TabBar::Paint(gd::Graphics& g)
	{
		if (m_theme == nullptr || m_fonts == nullptr)
		{
			return;
		}
		if (m_root == nullptr)
		{
			RebuildWidgets();
			ArrangeWidgets();
		}
		if (m_root == nullptr)
		{
			return;
		}

		UiPaintContext ctx;
		ctx.g = &g;
		ctx.clip = m_area;
		ctx.scale = m_scale;
		m_root->Paint(ctx);
	}

	bool TabBar::HitTest(int x, int y) const
	{
		return UiPointInRect(m_area, static_cast<float>(x), static_cast<float>(y));
	}

	void TabBar::CollectDebugBoxes(UiDebugBoxList& boxes)
	{
		UiComponent::CollectDebugBoxes(boxes);
		if (m_root != nullptr)
		{
			// ⚠️ 跳过根控件：它的矩形与标签栏区域完全重合（已被上一层登记过）。
			// 从控件树的**子节点**（各标签条 / 新建按钮）开始，层级 1。
			for (const std::unique_ptr<UiWidget>& child : m_root->Children())
			{
				if (child != nullptr)
				{
					child->CollectDebugBoxes(boxes, 1);
				}
			}
		}
		// 关闭按钮是「标签条内部的子块」，控件树里没有对应节点（由标签条控件自绘）⇒ 单独登记。
		for (const TabItem& tab : m_tabs)
		{
			boxes.Add(tab.closeRect, 2, L"x");
		}
	}

	int TabBar::TabAtPoint(int x, int y) const
	{
		const float fx = static_cast<float>(x);
		const float fy = static_cast<float>(y);
		for (std::size_t index = 0; index < m_tabs.size(); ++index)
		{
			if (UiPointInRect(m_tabs[index].rect, fx, fy))
			{
				return static_cast<int>(index);
			}
		}
		return -1;
	}

	bool TabBar::OnMouseMove(int x, int y)
	{
		// 拖动排序中：只跟踪鼠标位置，由覆盖层绘制插入指示。
		if (m_dragIndex >= 0)
		{
			if (x != m_dragMouseX)
			{
				m_dragMouseX = x;
				m_dragMoved = true;
				return true;
			}
			return false;
		}

		if (m_root == nullptr)
		{
			return false;
		}
		UiEvent event;
		event.kind = UiEventKind::MOUSE_MOVE;
		event.x = x;
		event.y = y;
		// 悬停链切换会通过 `Invalidate` 冒泡到根 ⇒ 用脏区判断是否需要重绘
		//（与旧实现"悬停下标/关闭/新建变化才重绘"等价，但不再手工维护三个下标）。
		return m_root->DispatchRedraw(event);
	}

	bool TabBar::OnLButtonDown(int x, int y)
	{
		m_pressedIndex = -1;
		m_pressedClose = false;
		m_pressedAdd = false;

		// 编辑态下点击其它位置先提交重命名。
		if (IsEditing())
		{
			TabBarResult ignored;
			OnEditKey(VK_RETURN, ignored);
		}

		if (UiPointInRect(m_addRect, static_cast<float>(x), static_cast<float>(y)))
		{
			m_pressedAdd = true;
			return true;
		}

		const int index = TabAtPoint(x, y);
		if (index < 0)
		{
			return false;
		}

		m_pressedIndex = index;
		m_dragIndex = index;
		m_dragMouseX = x;
		m_pressedX = x;
		m_dragMoved = false;
		m_pressedClose = UiPointInRect(m_tabs[static_cast<std::size_t>(index)].closeRect,
		                              static_cast<float>(x), static_cast<float>(y));

		// 自行判定双击：不依赖系统 WM_LBUTTONDBLCLK，行为在不同环境下更一致。
		const DWORD now = GetTickCount();
		const bool sameTab = (index == m_lastClickIndex);
		const DWORD elapsed = now - m_lastClickTick;
		if (!m_pressedClose && sameTab && elapsed <= GetDoubleClickTime())
		{
			m_lastClickIndex = -1;
			OnDoubleClick(x, y);
			return true;
		}
		m_lastClickIndex = m_pressedClose ? -1 : index;
		m_lastClickTick = now;
		return true;
	}

	bool TabBar::OnLButtonUp(int x, int y, TabBarResult& result)
	{
		result = TabBarResult();

		if (m_pressedAdd)
		{
			m_pressedAdd = false;
			if (UiPointInRect(m_addRect, static_cast<float>(x), static_cast<float>(y)))
			{
				result.type = TabBarResult::Type::ADD;
			}
			return true;
		}

		if (m_pressedIndex < 0)
		{
			m_dragIndex = -1;
			return false;
		}

		const int index = m_pressedIndex;
		const bool wasClose = m_pressedClose;
		const bool dragged = m_dragMoved && (std::abs(x - m_pressedX) > 3);
		m_pressedIndex = -1;
		m_pressedClose = false;
		m_dragIndex = -1;
		m_dragMoved = false;

		// 拖动超过阈值：按释放位置重新排序。
		if (dragged && !wasClose)
		{
			const int target = DropIndexAt(x);
			if (target >= 0 && target != index && target != index + 1)
			{
				result.type = TabBarResult::Type::REORDER;
				result.index = index;
				result.targetIndex = target;
			}
			return true;
		}

		if (TabAtPoint(x, y) != index)
		{
			return true;
		}

		if (wasClose)
		{
			// 关闭 ✕ 只在"按下后仍在 ✕ 上抬起"时生效：按住后移开再松开视为放弃
			// （与信号面板的分组/信号 ✕ 保持一致的交互语义）。
			if (UiPointInRect(m_tabs[static_cast<std::size_t>(index)].closeRect,
			                  static_cast<float>(x), static_cast<float>(y)))
			{
				result.type = TabBarResult::Type::CLOSE;
				result.index = index;
			}
		}
		else
		{
			result.type = TabBarResult::Type::SELECT;
			result.index = index;
		}
		return true;
	}

	int TabBar::DropIndexAt(int x) const
	{
		const float fx = static_cast<float>(x);
		for (std::size_t index = 0; index < m_tabs.size(); ++index)
		{
			const gd::RectF& rect = m_tabs[index].rect;
			if (fx < rect.X + rect.Width * 0.5f)
			{
				return static_cast<int>(index);
			}
		}
		return static_cast<int>(m_tabs.size());
	}

	bool TabBar::OnDoubleClick(int x, int y)
	{
		const int index = TabAtPoint(x, y);
		if (index < 0)
		{
			return false;
		}
		// 双击关闭按钮不进入重命名。
		if (UiPointInRect(m_tabs[static_cast<std::size_t>(index)].closeRect, static_cast<float>(x),
		                  static_cast<float>(y)))
		{
			return false;
		}

		m_editIndex = index;
		m_edit.Begin(m_tabs[static_cast<std::size_t>(index)].name, true, EditFilter::ANY, 0u);
		return true;
	}

	bool TabBar::OnEditChar(wchar_t character)
	{
		if (m_editIndex < 0)
		{
			return false;
		}

		// 剪贴板与全选快捷键经 WM_CHAR 送达（Ctrl+C/X/V/A 分别对应 3/24/22/1）。
		switch (character)
		{
		case 0x03: // Ctrl+C
			m_edit.CopyToClipboard(m_host);
			return false;
		case 0x18: // Ctrl+X
			return m_edit.CutToClipboard(m_host);
		case 0x16: // Ctrl+V
			return m_edit.PasteFromClipboard(m_host);
		case 0x01: // Ctrl+A
			m_edit.SelectAll();
			return true;
		default:
			break;
		}

		if (character == L'\r' || character == L'\n')
		{
			TabBarResult result;
			OnEditKey(VK_RETURN, result);
			return true;
		}
		// 退格/删除已由 WM_KEYDOWN 的 OnEditKey 处理，此处忽略全部控制字符。
		if (character < L' ' || character == 0x7F)
		{
			return false;
		}
		return m_edit.Insert(character);
	}

	bool TabBar::OnEditKey(WPARAM key, TabBarResult& result)
	{
		result = TabBarResult();
		if (m_editIndex < 0)
		{
			return false;
		}

		const int index = m_editIndex;
		const bool shift = (GetKeyState(VK_SHIFT) & 0x8000) != 0;
		const bool control = (GetKeyState(VK_CONTROL) & 0x8000) != 0;

		switch (key)
		{
		case VK_RETURN:
		{
			const std::wstring text = Trim(m_edit.Text());
			m_editIndex = -1;
			m_edit.End();
			if (!text.empty())
			{
				result.type = TabBarResult::Type::RENAME;
				result.index = index;
				result.text = text;
			}
			return true;
		}
		case VK_ESCAPE:
			m_editIndex = -1;
			m_edit.End();
			return true;
		case VK_BACK:
			return m_edit.Backspace();
		case VK_DELETE:
			return m_edit.DeleteForward();
		case VK_LEFT:
			return m_edit.MoveCaret(-1, shift);
		case VK_RIGHT:
			return m_edit.MoveCaret(1, shift);
		case VK_HOME:
			return m_edit.MoveHome(shift);
		case VK_END:
			return m_edit.MoveEnd(shift);
		case 'A':
			if (control)
			{
				m_edit.SelectAll();
			}
			return true;
		default:
			break;
		}
		return true;
	}

	bool TabBar::CollapseEditSelectionToEnd()
	{
		if (m_editIndex < 0)
		{
			return false;
		}
		return m_edit.DeselectToEnd();
	}

	gd::RectF TabBar::EditRect() const
	{
		if (m_editIndex < 0 || m_editIndex >= static_cast<int>(m_tabs.size()))
		{
			return gd::RectF();
		}
		const TabItem& tab = m_tabs[static_cast<std::size_t>(m_editIndex)];
		const float pad = 4.0f * m_scale;
		const float textLeft = tab.rect.X + kTabPadding * m_scale;
		const float textRight = tab.closeRect.X - kCloseGap * m_scale;
		return gd::RectF(textLeft, tab.rect.Y + pad, std::max(8.0f, textRight - textLeft),
		                 tab.rect.Height - pad * 2.0f);
	}

	bool TabBar::OnEditMouseDown(int x, int y)
	{
		if (m_editIndex < 0)
		{
			return false;
		}
		if (!UiPointInRect(EditRect(), static_cast<float>(x), static_cast<float>(y)))
		{
			return false;
		}
		UiEditFieldMouseDown(m_fonts->ui, EditRect(), m_edit, m_scale, x, y);
		return true;
	}

	bool TabBar::OnEditMouseMove(int x)
	{
		if (m_editIndex < 0)
		{
			return false;
		}
		UiEditFieldMouseMove(m_fonts->ui, EditRect(), m_edit, m_scale, x);
		return true;
	}

	bool TabBar::OnEditMouseUp()
	{
		if (m_editIndex < 0)
		{
			return false;
		}
		m_edit.EndDrag();
		return true;
	}

	bool TabBar::OnRButtonDown(int x, int y, int screenX, int screenY, TabBarResult& result)
	{
		result = TabBarResult();

		const int index = TabAtPoint(x, y);
		if (index < 0)
		{
			return false;
		}

		result.type = TabBarResult::Type::CONTEXT;
		result.index = index;
		result.screenX = screenX;
		result.screenY = screenY;
		return true;
	}

	bool TabBar::OnMouseLeave()
	{
		if (m_root == nullptr)
		{
			return false;
		}
		UiEvent event;
		event.kind = UiEventKind::MOUSE_LEAVE;
		event.x = 0;
		event.y = 0;
		m_root->Dispatch(event);
		return UiRectHasArea(m_root->TakeDirty());
	}

} // namespace jdi