#include <stdint.h>
#include <msp430.h>

#define PIEZO_BIT 0x04
#define BTN_BIT 0x40

#define POUT P2OUT
#define DC_BIT 0x01
#define DIN_BIT 0x02
#define CLK_BIT 0x04
#define RST_BIT 0x08

#define MODE_CMD 0
#define MODE_DATA 1

#define WIDTH 84
#define HEIGHT 48

void delay_ms(uint16_t ms) {
    while (ms--)
        __delay_cycles(1000 * 16);
}

inline void lcd_delay() {
    __delay_cycles(12);
}

void lcd_mode(char cmd) {
    if (cmd)
        POUT |= DC_BIT;
    else
        POUT &= ~DC_BIT;
}

void lcd_write(char data) {
    for (int i = 0; i < 8; i++) {
        if (data & 0x80)
            POUT |= DIN_BIT;
        else
            POUT &= ~DIN_BIT;

        POUT |= CLK_BIT;
        lcd_delay();
        POUT &= ~CLK_BIT;
        lcd_delay();

        data <<= 1;
    }

    POUT &= ~DIN_BIT;
}

void lcd_locate(char x, char y) {
    lcd_mode(MODE_CMD);
    lcd_delay();
    lcd_write(0x80 | x);
    lcd_write(0x40 | y);
    lcd_mode(MODE_DATA);
    lcd_delay();
}

void lcd_reset() {
    POUT &= ~RST_BIT;
    lcd_delay();
    POUT |= RST_BIT;
    lcd_delay();

    lcd_mode(MODE_CMD);
    lcd_delay();
    lcd_write(0x20);
    lcd_write(0x0c);
    lcd_mode(MODE_DATA);
    lcd_delay();

    lcd_locate(0, 0);

    for (int i = 0; i < WIDTH * HEIGHT/8; i++)
        lcd_write(0x00);
}

void sound_out(int count) {
    if (count == 0) {
        TACTL = TACLR;
        TACCTL1 = OUTMOD_0;
    } else {
        TACTL = TASSEL_2 | MC_1;
        TACCR0 = count;
        TACCR1 = count >> 1;
        TACCTL1 = OUTMOD_7;
    }
}

// 587Hz, 698Hz

// 1703

#include "gen.c"

void skull_trumpet() {
    char btn_prev = 1;
    int count = 0;

    int prev_frame = -1, frame = 0;

    while (1) {
        if (frame != prev_frame) {
            prev_frame = frame;
            lcd_locate(0, 0);

            const char *p = frames[frame];
            for (int i = 0; i < WIDTH*HEIGHT/8; i++)
                lcd_write(*p++);
        }

        char btn = !(P1IN & BTN_BIT);
        if (btn && !btn_prev) {
            sound_out(0);
            count = 142;
        }

        btn_prev = btn;

        if (count) {
            count--;

            if (count == 140) {
                sound_out(1703 * 16);
                frame = 3;
            } else if (count == 130) {
                sound_out(1432 * 16);
                frame = 6;
            } else if (count == 105) {
                sound_out(0);
                frame = 5;
            } else if (count == 90) {
                frame = 6;
            } else if (count == 75) {
                frame = 5;
            } else if (count == 60) {
                frame = 4;
            } else if (count == 45) {
                frame = 3;
            } else if (count == 30) {
                frame = 2;
            } else if (count == 15) {
                frame = 1;
            } else if (count == 0) {
                frame = 0;
            }
        }

        delay_ms(10);
    }
}

typedef short fixed;

const fixed sin_table[] = {0,1,3,4,6,7,9,10,12,14,15,17,18,20,21,23,25,26,28,29,31,32,34,36,37,39,40,42,43,45,46,48,49,51,53,54,56,57,59,60,62,63,65,66,68,69,71,72,74,75,77,78,80,81,83,84,86,87,89,90,92,93,95,96,97,99,100,102,103,105,106,108,109,110,112,113,115,116,117,119,120,122,123,124,126,127,128,130,131,132,134,135,136,138,139,140,142,143,144,146,147,148,149,151,152,153,155,156,157,158,159,161,162,163,164,166,167,168,169,170,171,173,174,175,176,177,178,179,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,211,212,213,214,215,216,217,217,218,219,220,221,221,222,223,224,225,225,226,227,227,228,229,230,230,231,232,232,233,234,234,235,235,236,237,237,238,238,239,239,240,241,241,242,242,243,243,244,244,244,245,245,246,246,247,247,247,248,248,249,249,249,250,250,250,251,251,251,251,252,252,252,252,253,253,253,253,254,254,254,254,254,254,255,255,255,255,255,255,255,255,255,255,255,255,255,255,256,255,255,255,255,255,255,255,255,255,255,255,255,255,255,254,254,254,254,254,254,253,253,253,253,252,252,252,252,251,251,251,251,250,250,250,249,249,249,248,248,247,247,247,246,246,245,245,244,244,244,243,243,242,242,241,241,240,239,239,238,238,237,237,236,235,235,234,234,233,232,232,231,230,230,229,228,227,227,226,225,225,224,223,222,221,221,220,219,218,217,217,216,215,214,213,212,211,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,179,178,177,176,175,174,173,171,170,169,168,167,166,164,163,162,161,159,158,157,156,155,153,152,151,149,148,147,146,144,143,142,140,139,138,136,135,134,132,131,130,128,127,126,124,123,122,120,119,117,116,115,113,112,110,109,108,106,105,103,102,100,99,97,96,95,93,92,90,89,87,86,84,83,81,80,78,77,75,74,72,71,69,68,66,65,63,62,60,59,57,56,54,53,51,49,48,46,45,43,42,40,39,37,36,34,32,31,29,28,26,25,23,21,20,18,17,15,14,12,10,9,7,6,4,3,1,0,-1,-3,-4,-6,-7,-9,-10,-12,-14,-15,-17,-18,-20,-21,-23,-25,-26,-28,-29,-31,-32,-34,-36,-37,-39,-40,-42,-43,-45,-46,-48,-49,-51,-53,-54,-56,-57,-59,-60,-62,-63,-65,-66,-68,-69,-71,-72,-74,-75,-77,-78,-80,-81,-83,-84,-86,-87,-89,-90,-92,-93,-95,-96,-97,-99,-100,-102,-103,-105,-106,-108,-109,-110,-112,-113,-115,-116,-117,-119,-120,-122,-123,-124,-126,-127,-128,-130,-131,-132,-134,-135,-136,-138,-139,-140,-142,-143,-144,-146,-147,-148,-149,-151,-152,-153,-155,-156,-157,-158,-159,-161,-162,-163,-164,-166,-167,-168,-169,-170,-171,-173,-174,-175,-176,-177,-178,-179,-181,-182,-183,-184,-185,-186,-187,-188,-189,-190,-191,-192,-193,-194,-195,-196,-197,-198,-199,-200,-201,-202,-203,-204,-205,-206,-207,-208,-209,-210,-211,-211,-212,-213,-214,-215,-216,-217,-217,-218,-219,-220,-221,-221,-222,-223,-224,-225,-225,-226,-227,-227,-228,-229,-230,-230,-231,-232,-232,-233,-234,-234,-235,-235,-236,-237,-237,-238,-238,-239,-239,-240,-241,-241,-242,-242,-243,-243,-244,-244,-244,-245,-245,-246,-246,-247,-247,-247,-248,-248,-249,-249,-249,-250,-250,-250,-251,-251,-251,-251,-252,-252,-252,-252,-253,-253,-253,-253,-254,-254,-254,-254,-254,-254,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-256,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-255,-254,-254,-254,-254,-254,-254,-253,-253,-253,-253,-252,-252,-252,-252,-251,-251,-251,-251,-250,-250,-250,-249,-249,-249,-248,-248,-247,-247,-247,-246,-246,-245,-245,-244,-244,-244,-243,-243,-242,-242,-241,-241,-240,-239,-239,-238,-238,-237,-237,-236,-235,-235,-234,-234,-233,-232,-232,-231,-230,-230,-229,-228,-227,-227,-226,-225,-225,-224,-223,-222,-221,-221,-220,-219,-218,-217,-217,-216,-215,-214,-213,-212,-211,-211,-210,-209,-208,-207,-206,-205,-204,-203,-202,-201,-200,-199,-198,-197,-196,-195,-194,-193,-192,-191,-190,-189,-188,-187,-186,-185,-184,-183,-182,-181,-179,-178,-177,-176,-175,-174,-173,-171,-170,-169,-168,-167,-166,-164,-163,-162,-161,-159,-158,-157,-156,-155,-153,-152,-151,-149,-148,-147,-146,-144,-143,-142,-140,-139,-138,-136,-135,-134,-132,-131,-130,-128,-127,-126,-124,-123,-122,-120,-119,-117,-116,-115,-113,-112,-110,-109,-108,-106,-105,-103,-102,-100,-99,-97,-96,-95,-93,-92,-90,-89,-87,-86,-84,-83,-81,-80,-78,-77,-75,-74,-72,-71,-69,-68,-66,-65,-63,-62,-60,-59,-57,-56,-54,-53,-51,-49,-48,-46,-45,-43,-42,-40,-39,-37,-36,-34,-32,-31,-29,-28,-26,-25,-23,-21,-20,-18,-17,-15,-14,-12,-10,-9,-7,-6,-4,-3,-1};

inline fixed intf(int i) {
    return (((fixed)i) << 8);
}

inline int fint(fixed f) {
    return (int)(f >> 8);
}

inline fixed fmul(fixed a, fixed b) {
    return ((long)a * (long)b) >> 8;
}

inline fixed fsin(int angle) {
    return sin_table[angle & 0x3ff];
}

inline fixed fcos(int angle) {
    return fsin(angle + 256);
}

char buf[WIDTH];

void rotozoom() {
    int angle = 0, angle2 = 0, angle3 = 0;

    while (1) {
        lcd_locate(0, 0);

        fixed s = fsin(angle),
              c = fcos(angle);

        fixed scale = 100 + (fsin(angle2) >> 2);

        fixed right_x = fmul(scale, c - s),
              right_y = fmul(scale, c + s);

        fixed down_x = right_y,
              down_y = -right_x;

        fixed rowstartx = 0,
              rowstarty = 0;

        for (int y = 0; y < HEIGHT; y += 8) {
            fixed tilestartx = rowstartx,
                  tilestarty = rowstarty;

            for (int x = 0; x < WIDTH; x++) {
                fixed sy = tilestarty,
                      sx = tilestartx;

                char byte = 0;

                for (char bit = 0x01; bit; bit <<= 1) {
                    if ((fint(sx) ^ fint(sy)) & 0x08)
                        byte |= bit;

                    sx += down_x;
                    sy += down_y;
                }

                lcd_write(byte);

                tilestartx += right_x;
                tilestarty += right_y;
            }

            rowstartx += down_x << 3;
            rowstarty += down_y << 3;
        }

        delay_ms(62);

        angle += 11;

        angle2 += 31;

        angle3 += 3;
    }
}

int main() {
    // Disable watchdog
    WDTCTL = WDTPW | WDTHOLD;

    // 1MHz internal timer
    BCSCTL1 = CALBC1_16MHZ;
    DCOCTL = CALDCO_16MHZ;

    // Button input, piezo output
    P1DIR = PIEZO_BIT;
    P1REN = BTN_BIT;
    P1OUT = BTN_BIT;

    P1SEL |= PIEZO_BIT;

    sound_out(0);

    // LCD output
    P2DIR = CLK_BIT | DIN_BIT | DC_BIT | RST_BIT;
    P2OUT = 0x00;

    lcd_reset();

    lcd_locate(0, 0);

    if (P1IN & BTN_BIT)
        rotozoom();
    else
        skull_trumpet();
}