#include "Toolbar.hpp"

#include <cmath>

#include "Utf8Util.hpp"

namespace jdi
{

	namespace
	{
		const float kButtonHeight = 30.0f;		/**< 按钮高度（逻辑像素）。 */
		const float kButtonGap = 6.0f;			/**< 按钮间距。 */
		const float kButtonPadding = 14.0f;		/**< 按钮左右内边距。 */
		const float kGroupGap = 18.0f;			/**< 分组间距。 */
		const float kButtonRadius = 5.0f;		/**< 按钮圆角半径。 */
		const float kSidePadding = 12.0f;		/**< 工具栏左右留白。 */
		const float kTopPadding = 8.0f;			/**< 工具栏上下留白。 */
	}

	Toolbar::Toolbar() = default;

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

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

	void Toolbar::SetDocumentLoaded(bool hasDocument)
	{
		m_documentLoaded = hasDocument;
	}

	void Toolbar::SetStatusText(const std::wstring& text)
	{
		m_statusText = text;
	}

	float Toolbar::DesiredHeight() const
	{
		return (kButtonHeight + kTopPadding * 2.0f) * m_scale;
	}

	bool Toolbar::IsEnabled(const Button& button) const
	{
		return button.needsDocument ? m_documentLoaded : true;
	}

	void Toolbar::Layout(const gd::RectF& area)
	{
		m_area = area;
		m_buttons.clear();

		if (m_fonts == nullptr || m_fonts->ui == nullptr)
		{
			return;
		}

		struct Spec
		{
			ToolbarAction action;
			const wchar_t* label;
			bool primary;
			bool needsDocument;
		};

		const Spec specs[] = {
		    {ToolbarAction::OPEN_FILE, L"打开 CSV", true, false},
		    {ToolbarAction::FIT_ALL, L"适应窗口", false, true},
		    {ToolbarAction::FIT_TIME, L"适应时间", false, true},
		    {ToolbarAction::ZOOM_IN, L"放大", false, true},
		    {ToolbarAction::ZOOM_OUT, L"缩小", false, true},
		    {ToolbarAction::MERGE_LANES, L"合并网格", false, true},
		    {ToolbarAction::SPLIT_LANES, L"每信号一格", false, true},
		};

		// 按钮宽度先按固定预算计算，避免依赖绘图上下文。
		float cursorX = area.X + kSidePadding * m_scale;
		const float top = area.Y + kTopPadding * m_scale;
		const float height = kButtonHeight * m_scale;

		for (const Spec& spec : specs)
		{
			Button button;
			button.action = spec.action;
			button.label = spec.label;
			button.primary = spec.primary;
			button.needsDocument = spec.needsDocument;
			button.width = (kButtonPadding * 2.0f +
			                static_cast<float>(button.label.size()) * 13.0f) * m_scale;
			button.rect = gd::RectF(cursorX, top, button.width, height);
			cursorX += button.width + kButtonGap * m_scale;

			if (spec.action == ToolbarAction::OPEN_FILE || spec.action == ToolbarAction::ZOOM_OUT ||
			    spec.action == ToolbarAction::SPLIT_LANES)
			{
				cursorX += kGroupGap * m_scale;
			}

			m_buttons.push_back(std::move(button));
		}
	}

	void Toolbar::Paint(gd::Graphics& g)
	{
		if (m_theme == nullptr || m_fonts == nullptr)
		{
			return;
		}

		UiFillRect(g, m_area, m_theme->toolbarBg);

		for (const Button& button : m_buttons)
		{
			const bool enabled = IsEnabled(button);
			std::uint32_t background = 0;
			std::uint32_t border = 0;
			std::uint32_t textColor = 0;

			if (button.primary)
			{
				background = enabled ? m_theme->accent : MixColor(m_theme->accent, m_theme->toolbarBg, 0.6);
				if (button.pressed)
				{
					background = MixColor(m_theme->accent, 0xFF000000u, 0.12);
				}
				else if (enabled && button.hover)
				{
					background = MixColor(m_theme->accent, 0xFFFFFFFFu, 0.12);
				}
				border = background;
				textColor = m_theme->textOnAccent;
			}
			else
			{
				background = m_theme->toolbarBg;
				if (button.pressed)
				{
					background = m_theme->pressed;
				}
				else if (enabled && button.hover)
				{
					background = m_theme->hover;
				}
				border = MixColor(m_theme->border, m_theme->toolbarBg, enabled ? 0.0 : 0.5);
				textColor = enabled ? m_theme->text : m_theme->textMuted;
			}

			if (background != m_theme->toolbarBg)
			{
				UiFillRoundRect(g, button.rect, kButtonRadius * m_scale, background);
			}
			if (!button.primary)
			{
				UiDrawRoundRect(g, button.rect, kButtonRadius * m_scale, border, 1.0f);
			}

			UiText(g, button.label, m_fonts->ui, button.rect, textColor, TextAlign::CENTER);
		}

		// 右侧状态文本。
		if (!m_statusText.empty())
		{
			const float rightPadding = kSidePadding * m_scale;
			gd::RectF textRect(m_area.X, m_area.Y, m_area.Width - rightPadding, m_area.Height);
			UiText(g, m_statusText, m_fonts->uiSmall, textRect, m_theme->textMuted, TextAlign::RIGHT);
		}

		// 底部分隔线。
		UiDrawLine(g, m_area.X, m_area.Y + m_area.Height - 1.0f, m_area.X + m_area.Width,
		           m_area.Y + m_area.Height - 1.0f, m_theme->border, 1.0f);
	}

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

	bool Toolbar::OnMouseMove(int x, int y)
	{
		int hoverIndex = -1;
		for (std::size_t index = 0; index < m_buttons.size(); ++index)
		{
			if (UiPointInRect(m_buttons[index].rect, static_cast<float>(x), static_cast<float>(y)))
			{
				hoverIndex = static_cast<int>(index);
				break;
			}
		}

		if (hoverIndex == m_hoverIndex)
		{
			return false;
		}
		m_hoverIndex = hoverIndex;
		return true;
	}

	bool Toolbar::OnLButtonDown(int x, int y, ToolbarAction& action)
	{
		action = ToolbarAction::NONE;

		for (std::size_t index = 0; index < m_buttons.size(); ++index)
		{
			Button& button = m_buttons[index];
			if (!UiPointInRect(button.rect, static_cast<float>(x), static_cast<float>(y)))
			{
				continue;
			}
			if (!IsEnabled(button))
			{
				return false;
			}

			m_pressedIndex = static_cast<int>(index);
			button.pressed = true;
			action = button.action;
			return true;
		}
		return false;
	}

	bool Toolbar::OnLButtonUp(int x, int y, ToolbarAction& action)
	{
		action = ToolbarAction::NONE;
		if (m_pressedIndex < 0)
		{
			return false;
		}

		const int index = m_pressedIndex;
		m_pressedIndex = -1;
		if (index >= static_cast<int>(m_buttons.size()))
		{
			return false;
		}

		Button& button = m_buttons[static_cast<std::size_t>(index)];
		button.pressed = false;

		const bool inside = UiPointInRect(button.rect, static_cast<float>(x), static_cast<float>(y));
		m_hoverIndex = inside ? index : -1;
		if (inside && IsEnabled(button))
		{
			action = button.action;
		}
		return true;
	}

	bool Toolbar::OnMouseLeave()
	{
		bool changed = false;
		if (m_hoverIndex >= 0)
		{
			m_hoverIndex = -1;
			changed = true;
		}
		if (m_pressedIndex >= 0)
		{
			if (m_pressedIndex < static_cast<int>(m_buttons.size()))
			{
				m_buttons[static_cast<std::size_t>(m_pressedIndex)].pressed = false;
			}
			m_pressedIndex = -1;
			changed = true;
		}
		return changed;
	}

} // namespace jdi