; screen variables
DEF vPreviousCardIndex EQU VARIABLES_START
def vBlocked equ vPreviousCardIndex + 1

ScreenCardRead:
  dw CardReadSetup
  dw CardReadUpdate
  dw CardReadDraw
  dw CardReadTeardown

CardReadSetup:
  ld a, 1 
  ldh [vBlocked], a 

  ld [vAsyncAfter+1], a 
  ld hl, UITilemap ; origin
  ld de, $9800 ; destination
  ld b, 18 ; height
  ld c, 20 ; width
  
  ld a, LOW(CopyTilesToMapThreadsafe)
  ld [vAsyncNext], a
  ld a, HIGH(CopyTilesToMapThreadsafe)
  ld [vAsyncNext+1], a 
  
  ld a, LOW(LoadCardDataAsync)
  ld [vAsyncAfter], a 
  ld a, HIGH(LoadCardDataAsync)
  ld [vAsyncAfter+1], a 
  call DoInAsyncVBlank
  ret

CardReadUpdate:
  ld hl, vTime
  ldh a, [rDELTAT]
  ld b, a 
  ldh a, [vTime]
  add a, b
  ldh [vTime], a 
  ldh a, [vTime+1]
  adc a, 0 
  ldh [vTime+1], a ; increment time. when the 16bit time register is greater 
  ; than 4096 ($10_00) then one second has passed. so that's satisfied when
  ; vTime+1 is equal to or greater than $10
  
  ldh a, [vTime+1]
  cp a, $01
  jp c, .doneTimer ; if the timer is less than $0100, skip to end
  
  ;otherwise reset the timer
  ld a, 0 
  ldh [vTime], a 
  ldh [vTime+1], a 
  
  ld hl, SquaresTiles
  ldh a, [vFrameCountSquares]
  inc a
  call ArrayClampLooping
  ldh [vFrameCountSquares], a 

.doneTimer
  ld hl, rMYBTNP
  bit 4, [hl]
  jp z, .doneWithB
  ld hl, ScreenSpreadSelect
  call ChangeScene
  ret
.doneWithB
  
  ldh a, [vSelectedSpreadCard]
  ld hl, rMYBTNP
  bit 1, [hl]
  jp z, :+ ; skip the following code if left is not pressed
  dec a 
:
  bit 0, [hl]
  jp z, :+ ; skip the following code if right is not pressed
  inc a 
:
  ldh [vSelectedSpreadCard], a 
  ldh a, [vCurrentSpread]
  ld l, a 
  ldh a, [vCurrentSpread+1]
  ld h, a 
  ldh a, [vSelectedSpreadCard]
  call ArrayClampLooping
  ldh [vSelectedSpreadCard], a 
  ldh [vSelectedCardIndex], a
  
  ldh a, [vSelectedCardIndex]
  ld hl, vPreviousCardIndex
  cp a, [hl]
  ret z ; if the selected card diddn't change, nothing to do
  
  ldh a, [vBlocked]
  cp a, 0 
  ret nz
  
  ld a, LOW(LoadCardDataAsync)
  ld [vAsyncAfter], a 
  ld a, HIGH(LoadCardDataAsync)
  ld [vAsyncAfter+1], a 
  call DoInAsyncVBlank
  
  
  ret

CardReadDraw:
  ld hl, SquaresTiles
  inc hl 
  ld b, 0
  ldh a, [vFrameCountSquares]
  ld c, a 
  add hl, bc 
  add hl, bc
  ld c, [hl]
  inc hl
  ld b, [hl]
  ld h, b
  ld l, c
  ld de, $8000+$100*16 + 1*16
  ld bc, (SquaresTileset8 - SquaresTileset7) / 8
  call CopyRangeUnsafeBy8s
  
  ; then draw the spread minimap

  ldh a, [vCurrentSpread]
  ld c, a 
  ldh a, [vCurrentSpread+1]
  ld b, a 
  ld hl, $9800 + (32*1)+11
  ldh a, [vSelectedSpreadCard]
  call DrawSpreadMinimap
  
  ldh a, [vCurrentSpread]
  ld l, a 
  ldh a, [vCurrentSpread+1]
  ld h, a 
  call PassList ; skip spread layout
  ldh a, [vSelectedSpreadCard]
  or a, a 
.loopThroughSpreadPositions
  jp z, .foundSpreadPositionDescription
  call PassList
  call PassList
  dec a 
  jp .loopThroughSpreadPositions
.foundSpreadPositionDescription
  ld de, $9800 + 32*5 + 11
  call PrintString
  ld de, $9800 + 32*6 + 11
  call PrintString
  
  ; the card data is loaded asynchronously, initiated in CardReadUpdate
  ret

CardReadTeardown:
  ret

UITilemap:
	db $0e, $0a, $0a, $0a, $0a, $0a, $0a, $0a, $0a, $0f, $09, $02, $02, $02, $02, $02, $02, $02, $08, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $03, $00, $00, $00, $00, $00, $00, $00, $04, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $03, $00, $00, $00, $00, $00, $00, $00, $04, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $03, $00, $00, $00, $00, $00, $00, $00, $04, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $03, $00, $00, $00, $00, $00, $00, $00, $04, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $03, $00, $00, $00, $00, $00, $00, $00, $04, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $03, $00, $00, $00, $00, $00, $00, $00, $04, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $06, $05, $05, $05, $05, $05, $05, $05, $07, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $01, $01, $01, $01, $01, $01, $01, $01, $01, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $01, $01, $01, $01, $01, $01, $01, $01, $01, $01
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $02, $02, $02, $02, $02, $02, $02, $02, $02, $02
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
	db $0b, $00, $00, $00, $00, $00, $00, $00, $00, $0c, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
	db $11, $0d, $0d, $0d, $0d, $0d, $0d, $0d, $0d, $10, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
UITilemapEnd: