#include "pm.h" // read this library if you don't recognise anything in capital letters

#include "sprites.h" // 16x16 b/w + transparency bird sprite
#include "map.h" // 8x8 b/w chequerboard map tile - formats for both of these can be found at https://wiki.sublab.net/index.php/PM_PRC

#include "input.h" // library for input - useful

#include "rng.h" // randomness

#define NUM_PIPES 4 // number of pipes, duh

// stuff for running once per frame

int frame_counter = 0; // used to count the number of frames that have passed

int trigger = 0;

void __interrupt irq_1_prc_done(void) // interrupt that is triggered after a frame is drawn
{
    IRQ_ACT1 |= IRQ1_PRC_COMPLETE; // acknowledge interrupt

    trigger = 1;
}

struct Pipe {
  unsigned char x;
  unsigned char y;
  unsigned char width;
  unsigned char enabled;
};

int main(void) // main function
{

    PRC_MODE = COPY_ENABLE|SPRITE_ENABLE|MAP_ENABLE|MAP_16X12;
    PRC_RATE = RATE_36FPS; // set up PRC to enable sprites, and a 16x12 tile background

    IRQ_ENA1 |= IRQ1_PRC_COMPLETE; // enable the frame complete interrupt to do fun stuff (see irq_1_prc_done)
    IRQ_PRI1 = PRI1_PRC(1); // give this high priority

    for(int i = 0; i < 16 * 12; i++)
        TILEMAP[i] = 0; // initialise the 16x12 tilemap with tile 0 (the chequerboard)

    PRC_SCROLL_X = 0;
    PRC_SCROLL_Y = 0; // reset the background scroll values

    PRC_SPR = (long)sprites; // load in sprite tiles
    PRC_MAP = (long)map; // load in map tiles

    int yspeed = 0;

    #define BIRD OAM[0]

    BIRD.x = 64;
    BIRD.y = 0x10;
    BIRD.tile = BIRD_TILE_0; // initialise the first and only sprite with position (32, 32), the bird sprite and enable it
    BIRD.ctrl = OAM_ENABLE;

    #define GAME_OVER OAM[1]

    GAME_OVER.x = 56;
    GAME_OVER.y = 40;
    GAME_OVER.tile = GAME_OVER_TILE;
    GAME_OVER.ctrl = 0;

    struct pipe[NUM_PIPES];


    randomise_pipe_0();

    PIPE_1_0.x = 0x60;
    PIPE_1_1.x = 0x50;
    PIPE_1_2.x = 0x40;
    PIPE_1_3.x = 0x30;
    PIPE_1_4.x = 0x20;
    PIPE_1_5.x = 0x10;

    PIPE_1_0.y = 0xF0;
    PIPE_1_1.y = 0xF0;
    PIPE_1_2.y = 0xF0;
    PIPE_1_3.y = 0xF0;
    PIPE_1_4.y = 0xF0;
    PIPE_1_5.y = 0xF0;

    // randomise_pipe_1();

    int pipe_1_state = 0;

    for(;;) // do this infinitely:
    {
        while(!trigger)
            ; // wait till the last frame has been drawn
        trigger = 0;

        frame_counter++; // increment the frame counter

        if(frame_counter == 3) // if 4 frames have passed,
        {
            frame_counter = 0; // reset the counter,
            PRC_SCROLL_Y++; // increment the map x scroll by 1
            PRC_SCROLL_Y &= 0x1F; // equivalent to % 32; makes it appear to scroll infinitely

            if(PIPE_0_0.y < 0x30 && !pipe_1_state)
            {
                pipe_1_state = 1;
                randomise_pipe_1();
            }

            if(PIPE_0_0.y > 0)
            {
                PIPE_0_0.y--;
                PIPE_0_1.y--;
                PIPE_0_2.y--;
                PIPE_0_3.y--;
                PIPE_0_4.y--;
                PIPE_0_5.y--;
            }
            else
            {
                randomise_pipe_0();
                PIPE_0_0.y = 0x50;
                PIPE_0_1.y = 0x50;
                PIPE_0_2.y = 0x50;
                PIPE_0_3.y = 0x50;
                PIPE_0_4.y = 0x50;
                PIPE_0_5.y = 0x50;
            }

            if(PIPE_1_0.y > 0)
            {
                PIPE_1_0.y--;
                PIPE_1_1.y--;
                PIPE_1_2.y--;
                PIPE_1_3.y--;
                PIPE_1_4.y--;
                PIPE_1_5.y--;
            }
            else
            {
                randomise_pipe_1();
                PIPE_1_0.y = 0x50;
                PIPE_1_1.y = 0x50;
                PIPE_1_2.y = 0x50;
                PIPE_1_3.y = 0x50;
                PIPE_1_4.y = 0x50;
                PIPE_1_5.y = 0x50;
            }

            if(pipe_1_state == 0)
            {
                PIPE_1_0.y = 0x50;
                PIPE_1_1.y = 0x50;
                PIPE_1_2.y = 0x50;
                PIPE_1_3.y = 0x50;
                PIPE_1_4.y = 0x50;
                PIPE_1_5.y = 0x50;
            }

        }

        /*
        ----------------PHYSICS----------------
        */

        if(BIRD.x + yspeed > 0x00) // if the bird won't be killed by the next move,
        {
            BIRD.x += yspeed; // add the y speed to the bird's y position (screen is rotated so x is y)
            if(!(frame_counter % 3))
                yspeed -= 1;
        }
        else
        {
            yspeed = 2;
            /*IRQ_ENA1 &= ~IRQ1_PRC_COMPLETE; // disable the frame end interrupt
            BIRD.ctrl &= ~OAM_ENABLE; // disable the bird sprite
            break; // break this infinite loop*/
        }

        if(BIRD.x > 0x60) // if the bird goes off the top of the screen,
        {
            yspeed = 0; // kill the y speed
            BIRD.x = 0x60; // lock the height
        }

        if(get_key(KEY_RIGHT))
            yspeed = 2; // if the right key is pressed, jump


    }

    // this happens when the bird dies

    IO_DATA |= BIT4; // write 1 to rumble data line to start rumbling
    for(int j = 0; j < 5000; j++) // wait for a bit
        ;
    IO_DATA &= ~BIT4; // write 0 to rumble data line to stop rumbling

    GAME_OVER.ctrl = OAM_ENABLE; // display the lose sprite
    for(int i = 0; i < 12; i++)
    {
        GAME_OVER.ctrl ^= OAM_INVERT; // flash it a few times
        for(int j = 0; j < 1000; j++)
            ;
    }

    return 0; // good practice
}