#include "animation.h"
#include "gpu.h"
#include "model_format_glb.h"

#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <string.h>

#define W 800
#define H 600

#define DT (1'000'000 / 60) // Assume 60 Hz for now

#define LIL_GUY_COUNT 2

static void
key_callback(GLFWwindow *window, int key, int scancode, int action, int mods)
{
	(void)window;
	(void)scancode;
	(void)mods;

	if (action != GLFW_PRESS)
		return;

	switch (key) {
	case GLFW_KEY_Q:
		glfwSetWindowShouldClose(window, GL_TRUE);
		break;
	}
}

int main(int argc, char *argv[])
{
	// Read model from passed path
	if (argc != 2) {
		fprintf(stderr, "Usage: %s PATH/TO/MODEL\n", argv[0]);
		return 1;
	}
	model_t model = model_format_glb_read(argv[1]);

	// Set up window
	glfwInit();
	glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API);
	glfwWindowHint(GLFW_RESIZABLE, GLFW_FALSE);
	GLFWwindow *window = glfwCreateWindow(W, H, "Foo", nullptr, nullptr);
	assert(window);

	// Register input callbacks
	glfwSetKeyCallback(window, key_callback);

	// Initialise GPU and load model
	gpu_ctx_t gpu;
	gpu_model_t gpu_model1, gpu_model2;
	gpu_init(&gpu, window, "Foo");
	gpu_model_load(&gpu, &model, &gpu_model1);
	gpu_model_load(&gpu, &model, &gpu_model2);

	// Initialise animation
	animation_state_t anim = animation_init(&model);

	const vec3_t cam = { 0, 4, -4 };
	const vec3_t tgt = { 0, 0.5, 0 };
	const vp_t vp = {
		.view = mat4_lookat(cam, tgt, (vec3_t) { 0, 1, 0 }),
		.proj = mat4_perspective((float)W / H, PI / 8, 0.1, 10.0),
	};
	mat4_t transform1 = mat4_mul(
	    MAT4_TRANSLATE(1, 0, 0),
	    (mat4_t) {
	        { 0, 0, -1, 0 },
	        { -1, 0, 0, 0 },
	        { 0, 1, 0, 0 },
	        { 0, 0, 0, 1 },
	    });
	mat4_t transform2 = mat4_mul(
	    MAT4_TRANSLATE(2, 0, 0),
	    mat4_mul(
	        MAT4_ROTATE_Y(PI),
	        (mat4_t) {
	            { 0, 0, -1, 0 },
	            { -1, 0, 0, 0 },
	            { 0, 1, 0, 0 },
	            { 0, 0, 0, 1 },
	        }));

	const mat4_t rot1 = MAT4_ROTATE_Y(PI / 170);
	const mat4_t rot2 = MAT4_ROTATE_Y(-PI / 340);
	animation_start(&anim, &model, 0);

	while (!glfwWindowShouldClose(window)) {
		glfwPollEvents();

		transform1 = mat4_mul(rot1, transform1);
		transform2 = mat4_mul(rot2, transform2);
		animation_update(&anim, &model, DT);

		gpu_render_begin(&gpu, vp);
		gpu_render_model(&gpu, &gpu_model1, anim.bone_matrices, transform1);
		gpu_render_model(&gpu, &gpu_model2, anim.bone_matrices, transform2);
		gpu_render_submit(&gpu);
	}

	// Clean up
	animation_cleanup(&anim);
	gpu_model_cleanup(&gpu, &gpu_model1);
	gpu_model_cleanup(&gpu, &gpu_model2);
	gpu_cleanup(&gpu);
	model_cleanup(&model);
	glfwDestroyWindow(window);
	glfwTerminate();

	return 0;
}