#include "CommonVertexIndex.hpp"

template <class TNumber>
static void AssignIndices(TNumber indices[6], TNumber startIdx) {
	// Triangle #1
	indices[0] = startIdx + 1; // Top right
	indices[1] = startIdx + 0; // Top left
	indices[2] = startIdx + 3; // Bottom left
	// Triangle #2
	indices[3] = startIdx + 1; // Top right
	indices[4] = startIdx + 3; // Bottom left
	indices[5] = startIdx + 2; // Bottom right
}

template <class TNumber>
static void AssignIndices(TNumber indices[6], TNumber topLeft, TNumber topRight, TNumber bottomRight, TNumber bottomLeft) {
	// Triangle #1
	indices[0] = topRight;
	indices[1] = topLeft;
	indices[2] = bottomLeft;
	// Triangle #2
	indices[3] = topRight;
	indices[4] = bottomLeft;
	indices[5] = bottomRight;
}

template <class TVertex>
static void AssignPositions(TVertex vertices[4], const Rect<float>& rect) {
	// Top left
	vertices[0].x = rect.x0();
	vertices[0].y = rect.y0();
	// Top right
	vertices[1].x = rect.x1();
	vertices[1].y = rect.y0();
	// Bottom right
	vertices[2].x = rect.x1();
	vertices[2].y = rect.y1();
	// Bottom left
	vertices[3].x = rect.x0();
	vertices[3].y = rect.y1();
}

template <class TVertex>
static void AssignPositions(TVertex vertices[4], glm::vec2 bl, glm::vec2 tr) {
	// Top left
	vertices[0].x = bl.x;
	vertices[0].y = tr.y;
	// Top right
	vertices[1].x = tr.x;
	vertices[1].y = tr.y;
	// Bottom right
	vertices[2].x = tr.x;
	vertices[2].y = bl.y;
	// Bottom left
	vertices[3].x = bl.x;
	vertices[3].y = bl.y;
}

template <class TVertex>
static void AssignDepths(TVertex vertices[4], float z) {
	for (int i = 0; i < 4; ++i) {
		auto& vert = vertices[i];
		vert.z = z;
	}
}

template <class TVertex>
static void AssignTexCoords(TVertex vertices[4], const Subregion& texcoords) {
	// Top left
	vertices[0].u = texcoords.u0;
	vertices[0].v = texcoords.v1;
	// Top right
	vertices[1].u = texcoords.u1;
	vertices[1].v = texcoords.v1;
	// Bottom right
	vertices[2].u = texcoords.u1;
	vertices[2].v = texcoords.v0;
	// Bottom left
	vertices[3].u = texcoords.u0;
	vertices[3].v = texcoords.v0;
}

template <class TVertex>
static void AssignColors(TVertex vertices[4], RgbaColor color) {
	for (int i = 0; i < 4; ++i) {
		auto& vert = vertices[i];
		vert.r = color.r;
		vert.g = color.g;
		vert.b = color.b;
		vert.a = color.a;
	}
}

void Index_U16::Assign(uint16_t indices[6], uint16_t startIdx) {
	::AssignIndices(indices, startIdx);
}

void Index_U16::Assign(uint16_t indices[6], uint16_t startIdx, uint16_t topLeft, uint16_t topRight, uint16_t bottomRight, uint16_t bottomLeft) {
	::AssignIndices<uint16_t>(indices, startIdx + topLeft, startIdx + topRight, startIdx + bottomRight, startIdx + bottomLeft);
}

void Index_U16::Assign(uint16_t indices[6], uint16_t topLeft, uint16_t topRight, uint16_t bottomRight, uint16_t bottomLeft) {
	::AssignIndices<uint16_t>(indices, topLeft, topRight, bottomRight, bottomLeft);
}

void Index_U32::Assign(uint32_t indices[6], uint32_t startIdx) {
	::AssignIndices(indices, startIdx);
}

void Index_U32::Assign(uint32_t indices[6], uint32_t startIdx, uint32_t topLeft, uint32_t topRight, uint32_t bottomRight, uint32_t bottomLeft) {
	::AssignIndices<uint32_t>(indices, startIdx + topLeft, startIdx + topRight, startIdx + bottomRight, startIdx + bottomLeft);
}

void Index_U32::Assign(uint32_t indices[6], uint32_t topLeft, uint32_t topRight, uint32_t bottomRight, uint32_t bottomLeft) {
	::AssignIndices<uint32_t>(indices, topLeft, topRight, bottomRight, bottomLeft);
}

void Vertex_PC::Assign(Vertex_PC vertices[4], const Rect<float>& rect) {
	::AssignPositions(vertices, rect);
}

void Vertex_PC::Assign(Vertex_PC vertices[4], glm::vec2 bottomLeft, glm::vec2 topRight) {
	::AssignPositions(vertices, bottomLeft, topRight);
}

void Vertex_PC::Assign(Vertex_PC vertices[4], float z) {
	::AssignDepths(vertices, z);
}

void Vertex_PC::Assign(Vertex_PC vertices[4], RgbaColor color) {
	::AssignColors(vertices, color);
}

void Vertex_PTC::Assign(Vertex_PTC vertices[4], const Rect<float>& rect) {
	::AssignPositions(vertices, rect);
}

void Vertex_PTC::Assign(Vertex_PTC vertices[4], glm::vec2 bottomLeft, glm::vec2 topRight) {
	::AssignPositions(vertices, bottomLeft, topRight);
}

void Vertex_PTC::Assign(Vertex_PTC vertices[4], float z) {
	::AssignDepths(vertices, z);
}

void Vertex_PTC::Assign(Vertex_PTC vertices[4], const Subregion& texcoords) {
	::AssignTexCoords(vertices, texcoords);
}

void Vertex_PTC::Assign(Vertex_PTC vertices[4], RgbaColor color) {
	::AssignColors(vertices, color);
}