#include "WindowAppItemIsometricLine.h"


WindowAppItemIsometricLine::WindowAppItemIsometricLine(const UI_ISOLINE_INFO& lineInfo) :
	m_isoLineInfo(lineInfo)
{

}


/// <summary>
/// 绘制线条
/// </summary>
/// <param name="painter"></param>
/// <param name="option"></param>
/// <param name="widget"></param>
void WindowAppItemIsometricLine::paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget /*= nullptr*/)
{
	Q_UNUSED(option);
	Q_UNUSED(widget);

	painter->setRenderHint(QPainter::Antialiasing, true);

	painter->save();

	// 绘制等宽线条
	this->drawIsoLines(painter);

	painter->restore();
}


/// <summary>
/// 绘制两个端点
/// </summary>
/// <param name="painter"></param>
void WindowAppItemIsometricLine::drawIsoLines(QPainter* painter)
{
	// 如果stretchDir参数是None，那么绘制的就是目标控件的等宽线
	// 因为目标控件的等宽线永远都只出现在右侧和下侧
	if (m_isoLineInfo.stretchDir == STRETCH_DIRECTION::DIR_NONE)
	{
		// 右侧的等高线
		if (m_isoLineInfo.sideDir == SIDE_DIRECTION::SIDE_RIGHT)
		{
			QLine rightLine = Utility::getSideLineByID(m_isoLineInfo.pWidget, (short)SIDE_DIRECTION::SIDE_RIGHT);
			this->drawIsoLines(painter, rightLine, SIDE_DIRECTION::SIDE_RIGHT);
		}
		// 下侧的等宽线
		else if (m_isoLineInfo.sideDir == SIDE_DIRECTION::SIDE_BOTTOM)
		{
			QLine bottomLine = Utility::getSideLineByID(m_isoLineInfo.pWidget, (short)SIDE_DIRECTION::SIDE_BOTTOM);
			this->drawIsoLines(painter, bottomLine, SIDE_DIRECTION::SIDE_BOTTOM);
		}
		// 错误，不应该走到这里
		else
		{
			vDebug() << "[Error] Invalid SideDirection:" << (short) m_isoLineInfo.sideDir;
		}
	}

	// 如果stretchDir参数是有值的，那么绘制的就是源控件的等宽线
	// 源控件的等宽线就需要根据拖拽方向来绘制在不同的位置了，需要额外解析一下
	else
	{
		STRETCH_DIRECTION sDir = m_isoLineInfo.stretchDir;

		// 如果是等高线
		if (m_isoLineInfo.sideDir == SIDE_DIRECTION::SIDE_RIGHT)
		{
			// 如果拖拽的是上、下、左上、左下，等高线在右侧
			if (sDir == STRETCH_DIRECTION::DIR_TOP
				|| sDir == STRETCH_DIRECTION::DIR_BOTTOM
				|| sDir == STRETCH_DIRECTION::DIR_LEFTTOP
				|| sDir == STRETCH_DIRECTION::DIR_LEFTBOTTOM
				)
			{
				// 获取右侧的边，然后在右侧边的右侧绘制等高线
				QLine rightLine = Utility::getSideLineByID(m_isoLineInfo.pWidget, (short)SIDE_DIRECTION::SIDE_RIGHT);
				this->drawIsoLines(painter, rightLine, SIDE_DIRECTION::SIDE_RIGHT);
			}
			
			// 如果拖拽的是右上、右下，等高线在左侧
			else if (sDir == STRETCH_DIRECTION::DIR_RIGHTTOP
				|| sDir == STRETCH_DIRECTION::DIR_RIGHTBOTTOM
				)
			{
				// 获取左侧的边，然后在左侧边的左侧绘制等高线
				QLine leftLine = Utility::getSideLineByID(m_isoLineInfo.pWidget, (short)SIDE_DIRECTION::SIDE_LEFT);
				this->drawIsoLines(painter, leftLine, SIDE_DIRECTION::SIDE_LEFT);
			}
		}

		// 如果是等宽线
		else if (m_isoLineInfo.sideDir == SIDE_DIRECTION::SIDE_BOTTOM)
		{
			// 如果拖拽的是左、右、左上、右上，等宽线在下侧
			if (sDir == STRETCH_DIRECTION::DIR_LEFT
				|| sDir == STRETCH_DIRECTION::DIR_RIGHT
				|| sDir == STRETCH_DIRECTION::DIR_LEFTTOP
				|| sDir == STRETCH_DIRECTION::DIR_RIGHTTOP
				)
			{
				// 获取底部的边，然后在底部边下侧绘制等宽线
				QLine bottomLine = Utility::getSideLineByID(m_isoLineInfo.pWidget, (short)SIDE_DIRECTION::SIDE_BOTTOM);
				this->drawIsoLines(painter, bottomLine, SIDE_DIRECTION::SIDE_BOTTOM);
			}

			// 如果拖拽的是右下、左下，等宽线在上侧
			else if (sDir == STRETCH_DIRECTION::DIR_LEFTBOTTOM
				|| sDir == STRETCH_DIRECTION::DIR_RIGHTBOTTOM
				)
			{
				// 获取顶部的边，然后在顶部边上侧绘制等宽线
				QLine topLine = Utility::getSideLineByID(m_isoLineInfo.pWidget, (short)SIDE_DIRECTION::SIDE_TOP);
				this->drawIsoLines(painter, topLine, SIDE_DIRECTION::SIDE_TOP);
			}
		}

	}
}


/// <summary>
/// 根据指定的位置绘制线条
/// </summary>
/// <param name="painter"></param>
/// <param name="side"></param>
/// <param name="sideDir"></param>
void WindowAppItemIsometricLine::drawIsoLines(QPainter* painter, const QLine& side, SIDE_DIRECTION sideDir)
{
	// 设置颜色风格
	painter->setPen(QPen(COLOR_REFLINE, PEN_LINE_WIDTH, Qt::SolidLine));

	QLine line1, line2;

	// 在右侧绘制
	if (sideDir == SIDE_DIRECTION::SIDE_RIGHT)
	{
		// 上侧标尺
		line1.setLine(
			side.p1().x() + ISOLINE_SPACE,
			side.p1().y() - ISOLINE_FIX,
			side.p1().x() + ISOLINE_SPACE + ISOLINE_MARK_LEN,
			side.p1().y() - ISOLINE_FIX
		);

		// 下侧标尺
		line2.setLine(
			side.p2().x() + ISOLINE_SPACE,
			side.p2().y() + ISOLINE_FIX,
			side.p2().x() + ISOLINE_SPACE + ISOLINE_MARK_LEN,
			side.p2().y() + ISOLINE_FIX
		);
	}

	// 在下侧绘制
	else if (sideDir == SIDE_DIRECTION::SIDE_BOTTOM)
	{
		// 左侧标尺
		line1.setLine(
			side.p1().x() - ISOLINE_FIX,
			side.p1().y() + ISOLINE_SPACE,
			side.p1().x() - ISOLINE_FIX,
			side.p1().y() + ISOLINE_SPACE + ISOLINE_MARK_LEN
		);

		// 右侧标尺
		line2.setLine(
			side.p2().x() + ISOLINE_FIX,
			side.p2().y() + ISOLINE_SPACE,
			side.p2().x() + ISOLINE_FIX,
			side.p2().y() + ISOLINE_SPACE + ISOLINE_MARK_LEN
		);
	}

	// 在左侧绘制
	else if (sideDir == SIDE_DIRECTION::SIDE_LEFT)
	{
		// 上侧标尺
		line1.setLine(
			side.p1().x() - ISOLINE_SPACE - ISOLINE_MARK_LEN,
			side.p1().y() - ISOLINE_FIX,
			side.p1().x() - ISOLINE_SPACE,
			side.p1().y() - ISOLINE_FIX
		);

		// 下侧标尺
		line2.setLine(
			side.p2().x() - ISOLINE_SPACE - ISOLINE_MARK_LEN,
			side.p2().y() + ISOLINE_FIX,
			side.p2().x() - ISOLINE_SPACE,
			side.p2().y() + ISOLINE_FIX
		);
	}

	// 在上侧绘制
	else if (sideDir == SIDE_DIRECTION::SIDE_TOP)
	{
		// 左侧标尺
		line1.setLine(
			side.p1().x() - ISOLINE_FIX,
			side.p1().y() - ISOLINE_SPACE - ISOLINE_MARK_LEN,
			side.p1().x() - ISOLINE_FIX,
			side.p1().y() - ISOLINE_SPACE
		);

		// 右侧标尺
		line2.setLine(
			side.p2().x() + ISOLINE_FIX,
			side.p2().y() - ISOLINE_SPACE - ISOLINE_MARK_LEN,
			side.p2().x() + ISOLINE_FIX,
			side.p2().y() - ISOLINE_SPACE
		);
	}

	// 错误，不应该执行到这里
	else
	{
		vDebug() << "[Error] Invalid side direction: " << (int)sideDir;

		return;
	}

	// 绘制标尺线条
	painter->drawLine(line1);
	painter->drawLine(line2);

	// 绘制箭头
	this->drawIsoArrowLines(painter, line1, line2, sideDir);

}


/// <summary>
/// 绘制箭头线条
/// </summary>
/// <param name="painter"></param>
void WindowAppItemIsometricLine::drawIsoArrowLines(QPainter* painter, QLine line1, QLine line2, SIDE_DIRECTION sideDir)
{
	QLineF arrowLine;

	// 如果是左侧边或者右侧边，那么就是纵向的等高线
	if (sideDir == SIDE_DIRECTION::SIDE_RIGHT || sideDir == SIDE_DIRECTION::SIDE_LEFT)
	{
		// 线条
		arrowLine.setLine(
			line1.x1() + ISOLINE_MARK_LEN / 2,
			line1.y1() + ISOLINE_ARROW_SIZE + 1,
			line2.x1() + ISOLINE_MARK_LEN / 2,
			line2.y1() - ISOLINE_ARROW_SIZE - 1
		);

		painter->drawLine(arrowLine);
	}

	// 其他情况就是横向的等宽线
	else
	{
		// 线条
		arrowLine.setLine(
			line1.x1() + ISOLINE_ARROW_SIZE + 1,
			line1.y1() + ISOLINE_MARK_LEN / 2,
			line2.x1() - ISOLINE_ARROW_SIZE - 1,
			line2.y1() + ISOLINE_MARK_LEN / 2
		);

		painter->drawLine(arrowLine);
	}

	// 加上箭头
	this->drawIsoArrow(painter, arrowLine);

	// 翻转线条，绘制另一侧箭头
	arrowLine.setPoints(arrowLine.p2(), arrowLine.p1());
	this->drawIsoArrow(painter, arrowLine);
}


/// <summary>
/// 为指定的线条绘制箭头
/// </summary>
/// <param name="isoLine"></param>
void WindowAppItemIsometricLine::drawIsoArrow(QPainter* painter, QLineF isoLine)
{
	// 获取单位向量
	QLineF v = isoLine.unitVector();
	// 设置箭头长度
	v.setLength(ISOLINE_ARROW_SIZE);
	v.translate(QPointF(isoLine.dx(), isoLine.dy()));

	// 计算法向量
	QLineF n = v.normalVector();
	// 设置箭头宽度
	n.setLength(n.length() * 0.5);
	// 计算两次法向量获取反向的法向量
	QLineF n2 = n.normalVector().normalVector();

	// 三个向量的终点即是三角形的三个顶点
	const QPointF points[3] = { v.p2(), n.p2(), n2.p2() };
	
	// 按照三个顶点绘制多边形，然后填充
	painter->setBrush(QBrush(COLOR_REFLINE, Qt::SolidPattern));
	painter->drawPolygon(points, 3);
}