#include <SDL2/SDL.h>

#include <assert.h>
#include <stdbool.h>
#include <math.h>

#include "game.h"

#define SPEED  0.00006
#define ROTATE 0.00004

Player g_player[MAX_PLAYERS];

static void moveplayer(int id, float speed) {
	g_player[id].vx += speed * cos(g_player[id].r * 2 * M_PI);
	g_player[id].vy += speed * sin(g_player[id].r * 2 * M_PI);
}

static void checkspacebound(float * a) {
	float x = *a;
	if(x < -1)
		x = abs(x);
	else if(x > 1)
		x = -x;
	*a = x;
}

void g_player_set(unsigned int id, bool live, float x, float y, float r, float vx, float vy, float vr) {
	assert(id < MAX_PLAYERS);
	g_player[id] = (Player) {
		.updated = true,
		.live    = live,
		.x       = x,
		.y       = y,
		.r       = r,
		.vx      = vx,
		.vy      = vy,
		.vr      = vr,
	};
}

void g_player_does(unsigned int id, DoesCode code) {
	assert(id < MAX_PLAYERS);
	g_player[id].updated = true;
	switch(code) {
	case DOES_UP:    moveplayer(id, SPEED); break;
	case DOES_DOWN:  moveplayer(id, -SPEED); break;
	case DOES_LEFT:  g_player[id].vr -= ROTATE; break;
	case DOES_RIGHT: g_player[id].vr += ROTATE; break;
	case DOES_FIRE:  break;
	}
}

void g_update() {
	for(int i = 0; i < MAX_PLAYERS; i++) {
		if(g_player[i].live) {
			g_player[i].updated = true;
			g_player[i].x += g_player[i].vx;
			g_player[i].y += g_player[i].vy;
			g_player[i].r += g_player[i].vr;
			checkspacebound(&g_player[i].x);
			checkspacebound(&g_player[i].y);
		}
	}
}