#version 450

layout(location = 1) in vec2 texCoord;
layout(location = 0) out vec4 outColor;

layout(set = 4, binding = 0) uniform LabelData
{
	vec4 color;
	vec2 textSize;
	vec2 bboxCenter;
	float radius;
	float arrowLength;
	float arrowWidth;
	bool hasRoundedCorners;
	bool hasArrow;
} labelInfo;

void main()
{
	if (labelInfo.hasRoundedCorners || labelInfo.hasArrow)
	{
		vec2 bbox = vec2(labelInfo.textSize);
		const float arrowLength = int(labelInfo.hasArrow) * labelInfo.arrowLength;
		float arrowWidth = labelInfo.arrowWidth;
		vec2 uvScaled = texCoord;

		float distX = min(uvScaled.x, bbox.x - uvScaled.x);
		float distY = min(uvScaled.y - arrowLength, bbox.y - uvScaled.y);
		float distanceFromCorner = distX * distY;

		if (distanceFromCorner < labelInfo.radius)
		{
			// plain arrow
			if (labelInfo.hasArrow && !labelInfo.hasRoundedCorners)
			{
				// Some bias to prevent line between arrow and label +
				// check that we are dealing with lower parts of the label where arrow should be drawn,
				// to prevent discarding fragments from upper corners
				if (distY <= 0.01 && uvScaled.y < (bbox.y - arrowWidth) && arrowLength != 0.0f)
				{
					arrowWidth = arrowWidth * ((arrowLength + distY) / arrowLength);
					if (distX < (bbox.x - arrowWidth) * 0.5)
					{
						discard;
					}
				}
			}
			// TODO: rounded corners + rounded arrow.
			// now renders rounded corners and sharp arrow
			else if (labelInfo.hasArrow && labelInfo.hasRoundedCorners)
			{
				if (distY <= 0.05 && uvScaled.y < (bbox.y - arrowWidth) && arrowLength != 0.0f)
				{
					arrowWidth = arrowWidth * ((arrowLength + distY) / arrowLength);
					if (distX < (bbox.x - arrowWidth) * 0.5)
					{
						discard;
					}
				}
				else
				{
					discard;
				}
			}
			// no arrow, rounded corners
			else
			{
				discard;
			}
		}
	}
	outColor = labelInfo.color;
}