#include "../../../shared_cpp/Renderer2d.h"
#include "../../../shared_cpp/types.h"
#include "../../../shared_cpp/mathlib.h"


struct SoftbodyRectangle {
	float32 width = 100;
	float32 height = 100;

	// Represents the density of springs that will be in the rectangle.
	int32 springDensity = 10;

	int32 numSubdivisions = 0;

	Mesh2d mesh;

	void load(Renderer2d* renderer) {
	    int32 numVertices = springDensity * springDensity; // Each subdivision is a square.
		int32 numIndices = 6 * ((springDensity - 1) * (springDensity - 1));
	    auto vertices = new Vertex2d[numVertices];
		auto indices = new GLuint[numIndices];

		int32 vIdx = 0;
		int32 iIdx = 0;
		float32 inverseDensity = 1.f / springDensity;
		float32 halfInv = inverseDensity - (inverseDensity / 2.f);
		for (int32 y = 0; y < springDensity; y++) {  // Rows
			for (int32 x = 0; x < springDensity; x++) { // Columns
			    Vector2 position = Vector2(x * inverseDensity - halfInv, y * inverseDensity- halfInv);
				vertices[vIdx] = { position, Vector4(1, 0, 0, 1) };

				if (y != springDensity - 1 && x != springDensity - 1) {
					indices[iIdx++] = vIdx;
					indices[iIdx++] = vIdx + 1;
					indices[iIdx++] = vIdx + springDensity;
					indices[iIdx++] = vIdx + springDensity;
					indices[iIdx++] = vIdx + springDensity + 1;
					indices[iIdx++] = vIdx + 1;
				}

				vIdx++;
			}
		}

		mesh.load(vertices, numVertices, indices, numIndices, renderer);
		mesh.model = Mat4x4().scale(Vector3(width, height, 0)).translateByVec2(Vector2(300, 400));

		delete [] vertices;
		delete [] indices;
	}

	void update(float32 dtSeconds) {

	}

	void render(Renderer2d* renderer) {
		mesh.render(renderer);
	}

	void unload() {
		mesh.unload();
	}
};