#include "stage.h"

#include "texturesdl.h"

#include <SDL/SDL_opengl.h>
#include <cmath>

class BulletPattern1 : public BulletPattern {
	public:
		BulletPattern1() {
			num_bullets = steps = 0;
			color_r = 0;
			color_g = 1;
			color_b = 0;
			stride = sizeof(float);
			bullets = new float[8*32*5];

				int k = 0;
				for(int j = 0; j < 8; j++) {
					for(float i = 0; i < M_PI; i += 0.1, k++) {
						bullets[k*5] = 0.5 + sinf(j % 2 ? M_PI_2 + i : M_PI - i + M_PI_2) * 0.09;
						bullets[k*5 + 1] = 0.8 + cosf(M_PI_2 + i) * 0.1;
						bullets[k*5 + 2] = sinf(j % 2 ? M_PI_2 + i : M_PI - i + M_PI_2) / 1000;
						bullets[k*5 + 3] = -0.002;
						bullets[k*5 + 4] = j * 24 + i * 6;
					}
				}

		};
		void update() {
			steps++;
			while(num_bullets < 256 && (unsigned int)(bullets[num_bullets*5 + 4]) < steps) {
				num_bullets++;
			}
			for(int i = 0; i < num_bullets; i++) {
				bullets[i*5] += bullets[i*5 + 2];
				bullets[i*5 + 1] += bullets[i*5 + 3];
			}
		}
};

class BulletPattern2 : public BulletPattern {
	public:
		BulletPattern2(float xpos, float ypos) {
			num_bullets = 0;
			color_r = 0.3;
			color_g = 0.3;
			color_b = 1.0;
			stride = sizeof(float)*2;
			bullets = new float[24*16*6];

			int k = 0;
			for(int j = 0; j < 24; j++) {
				for(float i = 0; i < 2 * M_PI; i += 0.4, k++) {
					bullets[k*6] = xpos;
					bullets[k*6+1] = ypos;
					bullets[k*6+2] = cosf(i) / 40;
					bullets[k*6+3] = sinf(i) / 40;
					bullets[k*6+4] = j * 10;
					bullets[k*6+5] = i;
				}
			}
		};
		void update() {
			steps++;
			while(num_bullets < 384 && (unsigned int)(bullets[num_bullets*6 + 4]) < steps) {
				num_bullets++;
			}
			for(int i = 0; i < num_bullets; i++) {
				float l = bullets[i*6 + 5] - log1pf((steps - bullets[i*6+4]));
				bullets[i*6+2] = cosf(l) / 500;
				bullets[i*6+3] = sinf(l) / 500;
				bullets[i*6] += bullets[i*6 + 2];
				bullets[i*6+1] += bullets[i*6 + 3];
			}
		}
};

Stage::Stage() {
	player = new Player();
	
	texture = new TextureSDL("textures/shot1.png");
	shader = new GLShaderProgram();
	
	patterns.push_back(new BulletPattern());
	patterns.push_back(new BulletPattern1());
	patterns.push_back(new BulletPattern2(0.2, 0.5));
	patterns.push_back(new BulletPattern2(0.5, 0.5));
	patterns.push_back(new BulletPattern2(0.8, 0.5));
	
	GLFragmentShader shader1("shaders/bullet_fragment.glsl");
	GLVertexShader shader2("shaders/bullet_vertex.glsl");
	shader->attach(shader1);
	shader->attach(shader2);
	shader->link();
}

void Stage::update() {
	player->update();
	
	for(std::vector<BulletPattern*>::iterator it = patterns.begin(); it < patterns.end(); it++) {
		(*it)->update();
	}
}

void Stage::draw() {
	player->draw();
	
	shader->use();
	glPointSize(32.0);
	glEnable(GL_TEXTURE_2D);
	glBindTexture(GL_TEXTURE_2D, texture->tex());
	
	for(std::vector<BulletPattern*>::iterator it = patterns.begin(); it < patterns.end(); it++) {
		BulletPattern *bp = (*it);
		glColor3f(bp->color_r, bp->color_g, bp->color_b);
		bp->draw();
	}
	
	glUseProgram(0);
}