#if VERA_VERSION == 7

const int24 VERA_COMPOSER_CTRL = $40040
const int24 VERA_PALETTE = $40200
const int24 VERA_LAYER_1 = $40000
const int24 VERA_LAYER_2 = $40010
const int24 VERA_SPRITE_CTRL = $40020
const int24 VERA_SPRITES = $40800

volatile byte vera_addr_hi @ $9f20
volatile byte vera_addr_mi @ $9f21
volatile byte vera_addr_lo @ $9f22

#elseif VERA_VERSION == 8

const int24 VERA_COMPOSER_CTRL = $F0000
const int24 VERA_PALETTE = $F1000
const int24 VERA_LAYER_1 = $F2000
const int24 VERA_LAYER_2 = $F3000
const int24 VERA_SPRITE_CTRL = $F4000
const int24 VERA_SPRITES = $F5000

volatile byte vera_addr_hi @ $9f22
volatile byte vera_addr_mi @ $9f21
volatile byte vera_addr_lo @ $9f20
volatile int24 vera_addr @ $9f20

#else
#error Unsupported VERA_VERSION
#endif

volatile byte vera_data1 @ $9f23
volatile byte vera_data2 @ $9f24
volatile byte vera_ctrl @ $9f25
volatile byte vera_ien @ $9f26
volatile byte vera_isr @ $9f27




struct vera_layer_setup {
    byte ctrl0
    byte ctrl1
    word map_base
    word tile_base
    word hscroll
    word vscroll
}

asm void set_vera_layer_internal(pointer.vera_layer_setup ax, byte y) {
    sta __reg
    stx __reg+1
    stz vera_ctrl
#if VERA_VERSION == 7
    lda $14
    sta vera_addr_hi
    stz vera_addr_mi
    sty vera_addr_lo
#elseif VERA_VERSION == 8
    lda $1F
    sta vera_addr_hi
    sty vera_addr_mi
    stz vera_addr_lo
#else
#error Unsupported VERA_VERSION
#endif
    ldy #0
    __set_layer_internal_loop:
    lda (__reg),y
    sta vera_data1
    iny
    cpy #sizeof(vera_layer_setup)
    bne __set_layer_internal_loop
    ? rts
}

asm void set_vera_layer1(pointer.vera_layer_setup ax) {
#if VERA_VERSION == 7
    ? ldy #0
#elseif VERA_VERSION == 8
    ? ldy #$20
#else
#error Unsupported VERA_VERSION
#endif
    ? jmp set_vera_layer_internal
}

asm void set_vera_layer2(pointer.vera_layer_setup ax) {
#if VERA_VERSION == 7
    ? ldy #$10
#elseif VERA_VERSION == 8
    ? ldy #$30
#else
#error Unsupported VERA_VERSION
#endif
    ? jmp set_vera_layer_internal
}

inline void vera_poke(int24 address, byte value) {
    vera_addr_lo = address.b0
    vera_addr_mi = address.b1
    vera_addr_hi = address.b2
    vera_ctrl = 0
    vera_data1 = value
}

inline byte vera_peek(int24 address) {
    vera_addr_lo = address.b0
    vera_addr_mi = address.b1
    vera_addr_hi = address.b2
    vera_ctrl = 0
    return vera_data1
}

inline void vera_fill(int24 address, byte value, word size) {
    word i
    vera_addr_lo = address.b0
    vera_addr_mi = address.b1
    vera_addr_hi = address.b2 | $10
    vera_ctrl = 0
    for i,0,paralleluntil,size {
        vera_data1 = value
    }
}

void vera_upload_large(int24 address, pointer source, word size) {
    word i
    vera_ctrl = 0
    vera_addr_lo = address.b0
    vera_addr_mi = address.b1
    vera_addr_hi = address.b2 | $10
    for i,0,paralleluntil,size {
        vera_data1 = source[i]
    }
}

inline void vera_upload(int24 address, pointer source, byte size) {
    vera_ctrl = 0
    vera_addr_lo = address.b0
    vera_addr_mi = address.b1
    vera_addr_hi = address.b2 | $10
    asm {
        ? ldy #0
        __vera_upload_loop:
        ? lda (source),y
        ! sta vera_data1
        ? iny
        ? cpy size
        ? bne __vera_upload_loop
    }
}

inline void vera_reset() {
    vera_ctrl = $80
    vera_ctrl = 0
}

inline void vera_set_sprites_enable(bool enabled) {
    vera_ctrl = 0
    vera_ctrl = 0
}

struct vera_sprite_data {
    word address
    word x
    word y
    byte ctrl0
    byte ctrl1
}

void vera_upload_sprite(byte sprite_id, pointer.vera_sprite_data source) {
    vera_ctrl = 0
    vera_addr_lo = sprite_id << 3
    vera_addr_mi = (sprite_id >> 5) | VERA_SPRITES.b1
    vera_addr_hi = VERA_SPRITES.b2 | $10
    asm {
        ? ldy #7
        __vera_upload_sprite_loop:
        ? lda (source),y
        ! sta vera_data0
        ? iny
        ? cpy #sizeof(vera_sprite_data)
        ? bne __vera_upload_sprite_loop
    }
}

inline void vera_set_sprites_enable(bool enabled) {
    vera_poke(VERA_SPRITE_CTRL, byte(enabled))
}

inline void vera_set_border(byte color) {
    vera_poke(VERA_COMPOSER_CTRL + 3, color)
}

alias set_border = vera_set_border