.org 0

.equ INT_VECTOR 0xff00

    call init

game_loop:
    halt

    call entities_erase
    call entities_update
    call entities_draw

    jmp game_loop

init:
    ; setup an int handler so we
    ; can use the frame int to sync
    ld a, >INT_VECTOR
    ld x, <INT_VECTOR
    ld b, <int_handler
    ld [a : x], b
    inc x
    ld b, >int_handler
    ld [a : x], b

    ; enable interrupts
    cif

    halt

    ; pattern for the BG
    ld b, 15
    ld a, 0xbf
    ld x, 0
    ld y, 0x40
fill_loop:
    ld [a : x], b
    xor b, 5
    inc x
    bno
    jmp fill_loop
    inc a
    dec y
    bnz
    jmp fill_loop

    call entities_draw

    ret

int_handler:
    iret

.include "entities.asm"
.include "player.asm"

;
; entity data
;
entities:
    ; type
    .db ET_PLAYER
    ; x, y
    .db 0, 0
    .dw player_sprite
    .dw player_update

    ; end of list
    .db ET_END

; sprite data
player_sprite:
    .incpng "assets/player.png"