import "pce";

bank zeropage @ 0x2000 : [vardata; 256];
bank stack @ 0x2100 : [vardata; 256];
bank prg @ 0xE000 : [constdata; 0x2000];
bank chr @ 0x8000 : [constdata; 0x4000];

in zeropage {
    var b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14, b15 : u8;
    var w0 @ &b0, w2 @ &b2, w4 @ &b4, w6 @ &b6, w8 @ &b8 : u16;
    var mosaic : u8;
    var timer : u8;
}

in prg {
    #[fallthrough] func main() {
        // Disable decimal arithmetic.
        decimal = false;
        // Disable interrupts.
        nointerrupt = true;
        // Enable turbo mode on CPU.
        turbo_speed = true;
        // mpr7 = a = 0; by power-on
        // MPR0 = I/O page
        mpr0 = a = 0xFF;
        // MPR1 = RAM
        mpr1 = a = 0xF8;
        // MPR4/5 = data bank
        mpr4 = a = 1;
        mpr5 = a = 2;
        // Prepare stack.
        s = x = 0xFF;

        a = pce.vdc.status;
        pce.irq.disable = a = pce.irq.INTERRUPT_ALL;
        pce.irq.acknowledge = a;
        pce.timer.control = 0;

        vdc_select = pce.vdc.SELECT_CONTROL;
        vdc_data_l = 0;
        vdc_data_h = 0;
        vdc_select = pce.vdc.SELECT_SCANLINE_COMPARE;
        vdc_data_l = 0;
        vdc_data_h = 0;
        vdc_select = pce.vdc.SELECT_SCROLL_X;
        vdc_data_l = 0;
        vdc_data_h = 0;
        vdc_select = pce.vdc.SELECT_SCROLL_Y;
        vdc_data_l = 0;
        vdc_data_h = 0;
        vdc_select = pce.vdc.SELECT_MEMORY_SIZE;
        vdc_data_l = pce.vdc.DATA_L_MEMORY_SIZE_TILEMAP_32x32;
        vdc_data_h = 0;
        vdc_select = pce.vdc.SELECT_HSYNC_SETTING;
        vdc_data_l = 0x02;
        vdc_data_h = 0x02;
        vdc_select = pce.vdc.SELECT_HDISP_SETTING;
        vdc_data_l = 0x1F;
        vdc_data_h = 0x04;
        vdc_select = pce.vdc.SELECT_VSYNC_SETTING;
        vdc_data_l = 0x07;
        vdc_data_h = 0x0D;
        vdc_select = pce.vdc.SELECT_VDISP_HEIGHT;
        vdc_data_l = 0xDF;
        vdc_data_h = 0x00;
        vdc_select = pce.vdc.SELECT_VDISP_END;
        vdc_data_l = 0x03;
        vdc_data_h = 0x00;
        vdc_select = pce.vdc.SELECT_DMA_CONTROL;
        vdc_data_l = pce.vdc.DATA_L_DMA_CONTROL_SATB_AUTO_TRANSFER;
        vdc_data_h = 0x00;
        vdc_select = pce.vdc.SELECT_SATB_SOURCE_ADDRESS;
        vdc_data_l = 0x00;
        vdc_data_h = 0x7F;

        pce.vce.control = a = pce.vce.CONTROL_FIELD_EXTRA_LINE;
        pce.vce.address_l = a = 0;
        pce.vce.address_h = a = 0;
        load_alt_inc_repeat(&pce.vce.data_l as u16, &bkg_palette_data as u16, sizeof(typeof(bkg_palette_data)));

        let TILESET_DEST_ADDRESS = 0x1000;
        vdc_select = pce.vdc.SELECT_VRAM_WRITE_ADDRESS;
        vdc_data_l = <:TILESET_DEST_ADDRESS;
        vdc_data_h = >:TILESET_DEST_ADDRESS;
        vdc_select = pce.vdc.SELECT_VRAM_DATA;
        load_alt_inc_repeat(&pce.vdc.data_l as u16, &hello_tiles_chr as u16, sizeof(typeof(hello_tiles_chr)));

        let START_X = 10;
        let START_Y = 13;
        let TILEMAP_ADDRESS = pce.vdc.DATA_VRAM_ADDRESS_TILEMAP + START_Y * 32 + START_X;
        let TILE_BASE_INDEX = TILESET_DEST_ADDRESS / 16;

        vdc_select = pce.vdc.SELECT_VRAM_WRITE_ADDRESS;
        vdc_data_l = <:TILEMAP_ADDRESS;
        vdc_data_h = >:TILEMAP_ADDRESS;
        vdc_select = pce.vdc.SELECT_VRAM_DATA;

        x = 0;
        do {            
            pce.vdc.data_l = a = <:TILE_BASE_INDEX + message[x];
            pce.vdc.data_h = a = >:TILE_BASE_INDEX +# 0;
            x++;
        } while x != message.len;

        vdc_select = pce.vdc.SELECT_CONTROL;
        vdc_data_l = pce.vdc.DATA_L_CONTROL_ENABLE_BG;
        vdc_data_h = 0x00;

        while true {}
    }

    let rgb_pack(r, g, b) = ((r & 0x7) << 3) | ((g & 0x7) << 6) | (b & 0x7);

    const bkg_palette_data : [u16] = [
        rgb_pack(6, 3, 4), rgb_pack(1, 1, 3), rgb_pack(0, 0, 0), rgb_pack(0, 0, 0),
        rgb_pack(0, 0, 0), rgb_pack(0, 0, 0), rgb_pack(0, 0, 0), rgb_pack(0, 0, 0),
        rgb_pack(0, 0, 0), rgb_pack(0, 0, 0), rgb_pack(0, 0, 0), rgb_pack(0, 0, 0),
        rgb_pack(0, 0, 0), rgb_pack(0, 0, 0), rgb_pack(0, 0, 0), rgb_pack(7, 7, 7),
    ];

    const message = "HELLO  WORLD";

    const @ 0xFFFE = main;
}

in chr {
    const hello_tiles_chr = embed "hello_tiles.chr";
    const minirpg_sprites_chr = embed "minirpg_sprites.chr";
}