#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "font.h"

//some useful colors
#define BLACK 0x0000
#define WHITE 0xFFFF
#define BLUE 0xEE00
#define CYAN 0xFF00
#define GREEN 0x0EE0
#define RED 0x00FF
#define MAGENTA 0xF00F
#define BROWN 0x0D0D

//defines for the video system
unsigned short* videoBuffer = (unsigned short*)0x6000000;
#define DISPLAY_CONTROLLER *(unsigned long*)0x4000000
#define VIDC_BASE_HALF	((volatile unsigned short int*) 0x04000000)	
#define VCOUNT		(VIDC_BASE_HALF[3])	

//pointer to the button interface
volatile unsigned int *BUTTONS = (volatile unsigned int *)0x04000130;

#define VIDEO_MODE_3 0x3
#define BACKGROUND2 0x400
#define SCREEN_W 240
#define SCREEN_H 160

//game constants
#define BALL_SIZE 3
#define PADDLE_WIDTH 30
#define PADDLE_HEIGHT 8
#define PADDLE_SPEED 4
#define BLOCK_WIDTH 20
#define BLOCK_HEIGHT 10

//global variables
int paddleX = 120;
int paddleY = 150;
int ballX = 120, ballY = 139;
int velX = 2, velY = -1;
int score = 0;
int lives = 5;
int play = 1;

int blocks[10][6];

void setMode(int mode)
{
    DISPLAY_CONTROLLER = mode | BACKGROUND2;
}

inline void drawPixel(int x, int y, unsigned short color)
{
	videoBuffer[y * 240 + x] = color;
}

inline unsigned short getpixel(int x, int y)
{
    return videoBuffer[y * 240 + x];
}


int buttonPressed(int button)
{
    //see if UP button is pressed
    if (!((*BUTTONS) & button))
        return 1;
    else
        return 0;
}

//draw text using characters contained in font.h
void print(int left, int top, char *str, unsigned short color)
{
    int x, y, draw;
    int pos = 0;
    char letter;

    //look at all characters in this string
    while (*str)
    {
        //get current character ASCII code
        letter = (*str++) - 32;

        //draw the character
        for(y = 0; y < 8; y++)
            for(x = 0; x < 8; x++)
            {
                //grab a pixel from the font character
                draw = font[letter * 64 + y * 8 + x];

                //if pixel = 1, then draw it
                if (draw)
                    drawPixel(left + pos + x, top + y, color);
            }

        //jump over 8 pixels
        pos += 8;
    }
}

void drawbox(int left, int top, int right, int bottom, unsigned short color)
{
   int x = left, y;
   for (y = top; y < bottom; y++) {
       for (x = left; x < right; x++)
            drawPixel(x, y, color);
   }
}

void printScore()
{
    //display score
    char s[5];
    sprintf(s,"%i",score);
    print(5,1,s,WHITE);
}

void printLives()
{
    //display lives
    char s[6];
    sprintf(s,"%i",lives);
    print(219,1,s,WHITE);
}

void eraseScore()
{
drawbox(0,0,24,9,BLACK);
}

void eraseLives()
{
 drawbox(210,0,240,9,BLACK);
}

void updateBall()
{
    if (ballX < 1 || ballX > SCREEN_W - BALL_SIZE - 1)
    {
        velX *= -1;
    }

    if (ballY < 9)
    {
        velY *= -1;
    }

    if (ballY > SCREEN_H - BALL_SIZE - 1)
    {
        ballY = paddleY - 40;
        eraseLives();
        lives = lives - 1;
        velY = -1;
    }

    ballX += velX;
    ballY += velY;
}

void drawBall()
{
	drawbox(ballX, ballY, ballX + BALL_SIZE, ballY + BALL_SIZE, RED);
}

void eraseBall()
{
	drawbox(ballX, ballY, ballX + BALL_SIZE, ballY + BALL_SIZE, BLACK);
}

void drawBlock(int row, int col, int color)
{
    int startx,starty;

    startx = 10 + row * (BLOCK_WIDTH+2);
    starty = 20 + col * (BLOCK_HEIGHT+2);
    drawbox(startx, starty, startx + BLOCK_WIDTH, starty + BLOCK_HEIGHT, color);
}

void drawBlocks()
{
    int x,y;

    for (y = 0; y < 6; y++)  {
       for (x = 0; x < 10; x++)  {

           //is this block still visible?
           if (blocks[x][y] == 1) {
               drawBlock(x,y, GREEN);
           }

       }
    }
}

void drawPaddle()
{
	drawbox(paddleX, paddleY, paddleX + PADDLE_WIDTH, paddleY + PADDLE_HEIGHT, WHITE);
}

void erasePaddle()
{
	drawbox(paddleX-4, paddleY, paddleX + PADDLE_WIDTH+4, paddleY + PADDLE_HEIGHT, BLACK);
}

void updatePaddle()
{
    //check for LEFT button press
    if (buttonPressed(32))
    {
        if (paddleX > 1)
            paddleX -= PADDLE_SPEED;
    }

    //check for RIGHT button press
    if (buttonPressed(16))
    {
        if (paddleX < SCREEN_W - PADDLE_WIDTH - 2)
            paddleX += PADDLE_SPEED;
    }
}

int inside(int x,int y, int left, int top, int right, int bottom)
{
    return (x > left && x < right && y > top && y < bottom);
}

void testPaddleCollision()
{
    int x1 = paddleX;
    int y1 = paddleY;
    int x2 = paddleX + PADDLE_WIDTH;
    int y2 = paddleY + PADDLE_HEIGHT;
    int bx = ballX + BALL_SIZE/2;
    int by = ballY + BALL_SIZE/2;

    if (inside(bx,by,x1,y1,x2,y2)) {
        velY *= -1;
        ballY += velY;
    }
}

void testBlockCollisions()
{
    int x,y,x1,y1,x2,y2,bx,by;

    for (y = 0; y < 6; y++)  {
        for (x = 0; x < 10; x++)  {

            if (blocks[x][y] == 1) {

                x1 = 10 + x * (BLOCK_WIDTH+2);
                y1 = 20 + y * (BLOCK_HEIGHT+2);
                x2 = x1 + BLOCK_WIDTH;
                y2 = y1 + BLOCK_HEIGHT;
                bx = ballX + BALL_SIZE/2;
                by = ballY + BALL_SIZE/2;

                if (inside(bx, by, x1, y1, x2, y2)) {
                    eraseScore();
                    score++;
                    drawBlock(x,y,BLACK);
                    blocks[x][y] = 0;
                    eraseBall();
                    velY *= -1;
                    ballY += velY;
                }
            }

        }
    }
}

int endProgram()
    {
     return 0;
    }

void waitRetrace()
{
	while (VCOUNT != 160);
	while (VCOUNT == 160);
}

void clearScreen() {
    drawbox(0,0,239,159,0x0000);
}

void eraseText()
{
 drawbox(0,0,SCREEN_W-1,SCREEN_H-1,BLACK);
}

void resetGame()
{
    if(score == 60 || lives <=0)
    {
        clearScreen();
        print(SCREEN_W/2-32,SCREEN_H/2,"WOULD YOU LIKE",WHITE);
        print(SCREEN_W/2-32,SCREEN_H/2 + 10,"TO PLAY AGAIN?",WHITE);
        print(SCREEN_W/2-32,SCREEN_H/2 + 20,"(UP = Y DOWN = N)",WHITE);
        while(play == 1)
        {
            //check for UP button Press
            if (buttonPressed(64))
            {
             clearScreen();
             play = 0;
            }
            //check for DOWN button Press
            if(buttonPressed(128))
            {
            clearScreen();
            }
        }
    }
}

void drawScreen()
{
 drawBall();
 drawPaddle();
 drawBlocks();
}

void updateScreen()
{
    updateBall();
    updatePaddle();
}

int main(void)
{
    //init video mode 3 (240x160)
    setMode(VIDEO_MODE_3);

    //turn on the blocks so they are all visible
    int x,y;
    for (y = 0; y < 6; y++)
    {
        for (x = 0; x < 10; x++)
        {
            blocks[x][y] = 1;
        }
    }

    //display title
    print(SCREEN_W/2-32,1,"BREAKOUT", BLUE);

    //game loop
    while(play == 1)
    {
        waitRetrace();

        eraseBall();
        erasePaddle();
        
        updateScreen();
        
        drawScreen();
        
        testBlockCollisions();
        testPaddleCollision();
        
        printScore();
        printLives();
        
        resetGame();
    }

    return 0;
}