include "includes.i"
	
	xdef	copperList
	xdef	copperListBpl1Ptr
	xdef	copperListBpl2Ptr	
	xdef 	backgroundOnscreen
	xdef	backgroundOffscreen
	xdef	foregroundOnscreen
	xdef	foregroundOffscreen
	xdef	foregroundScrollX
	xdef	backgroundScrollX
	xdef	map
	xdef	itemsMap
	xdef   	mapSize
	xdef	moving
	
byteMap:
	dc.l	Entry
	dc.l	endCode-byteMap

Entry:
	lea	userstack,a7
	lea 	CUSTOM,a6

	move	#$7ff,DMACON(a6)	; disable all dma
	move	#$7fff,INTENA(a6) 	; disable all interrupts		
	
	lea	Level3InterruptHandler,a3
 	move.l	a3,LVL3_INT_VECTOR			

	;; d0 - fg bitplane pointer offset
	;; d1 - bg bitplane pointer offset
	move.l	#0,d0
	move.l	#1,d1
	jsr	SwitchBuffers		
	
	move.w	#(INTF_SETCLR|INTF_VERTB|INTF_INTEN),INTENA(a6)	
 	move.w	#(DMAF_BLITTER|DMAF_SETCLR!DMAF_MASTER),DMACON(a6) 		

	lea	panelCopperListBpl1Ptr,a0
	lea	panel,a1
	jsr	PokePanelBitplanePointers
	jsr	Init		  ; enable the playfield		

	jsr	InstallSpriteColorPalette
	jsr	InstallGreyPalette
	
Reset:
	move.l	#0,foregroundScrollX
	move.l	#0,backgroundScrollX
	jsr 	BlueFill
	move.l	#-1,frameCount		

MainLoop:
	MOVE.W  #$0024,BPLCON2(a6)

SetupBoardLoop:
	add.l	#1,frameCount
	move.l	frameCount,d6		
	move.l	#FOREGROUND_SCROLL_PIXELS*15,foregroundScrollPixels
	;; jsr	WaitVerticalBlank	
	bsr	HoriScrollPlayfield
	jsr 	SwitchBuffers	    ; takes bitplane pointer offset in d0
	move.l	foregroundScrollX,d0
	move.w	#1,moving
	bsr 	Update
	bsr	RenderNextForegroundFrame	
	bsr 	RenderNextBackgroundFrame			
	cmp.l	#FOREGROUND_PLAYAREA_WIDTH_WORDS,frameCount
	bge	.gotoGameLoop
	bra	SetupBoardLoop

.gotoGameLoop:	
	jsr	WaitVerticalBlank
	bra	GameLoop
	
GameLoop:
	add.l	#1,frameCount
	move.l	frameCount,d6			

	cmp.l	#FOREGROUND_PLAYAREA_WIDTH_WORDS+25,d6
	bne	.c1
	move.w	#(DMAF_SPRITE|DMAF_BLITTER|DMAF_SETCLR!DMAF_COPPER!DMAF_RASTER!DMAF_MASTER),DMACON(a6)
	jsr	InitialisePig
.c1:
	bsr	InstallNextGreyPalette
	move.l	#FOREGROUND_SCROLL_PIXELS,foregroundScrollPixels
	jsr	WaitVerticalBlank	
	bsr	HoriScrollPlayfield
	jsr 	SwitchBuffers	    ; takes bitplane pointer offset in d0

	move.l	foregroundScrollX,d0
	lsr.l	#FOREGROUND_SCROLL_SHIFT_CONVERT,d0 ; convert to pixels		
	and.b	#$f,d0
	cmp.b	#$f,d0
	bne	.s2
	move.w	#0,moving
.s2:
	
	jsr	ProcessJoystick
	bsr 	Update
	bsr	RenderNextForegroundFrame	
	bsr 	RenderNextBackgroundFrame			

	if 0
	 move.w	#$f00,COLOR00(a6)
	endif

	bra	GameLoop
	
Update:
	;; right
	jsr	UpdatePig
	
.backgroundUpdates:
	add.l	#BACKGROUND_SCROLL_PIXELS,backgroundScrollX		
	btst	#FOREGROUND_DELAY_BIT,d6
	beq	.skipForegroundUpdates
	;; ---- Foreground updates ----------------------------------------	
.foregroundUpdates:

	move.l	foregroundScrollX,d0
	lsr.l	#FOREGROUND_SCROLL_SHIFT_CONVERT,d0 ; convert to pixels
	andi.l	#$f,d0

	cmp.w	#0,moving
	beq	.c1
	move.l	foregroundScrollPixels,d0
	add.l	d0,foregroundScrollX

	jsr	ScrollSprites

	move.l	foregroundScrollX,d0
	lsr.l	#FOREGROUND_SCROLL_SHIFT_CONVERT,d0 ; convert to pixels
	andi.l	#$f,d0
	cmp.b	#0,d0
	bne	.c1
	bsr	ResetAnimPattern
	bsr	ResetDeAnimPattern
.c1:

	
.skipForegroundUpdates:
	
	rts
	
HoriScrollPlayfield:
	;; d0 - fg x position in pixels
	;; d1 - bg x position in pixels	
	;; 	movem.l	d0-d6,-(sp)
	
	move.l	backgroundScrollX,d0
	lsr.l	#BACKGROUND_SCROLL_SHIFT_CONVERT,d0		; convert to pixels	
	move.w	d0,d2
	lsr.w   #3,d0		; bytes to scroll
	and.w   #$F,d2		; pixels = 0xf - (hpos - (hpos_bytes*8))
	move.w  #$F,d0
	sub.w   d2,d0		; bits to delay	
	move.w	d0,d5		; d5 == bg bits to delay

	move.l	foregroundScrollX,d0
	lsr.l	#FOREGROUND_SCROLL_SHIFT_CONVERT,d0		; convert to pixels
	move.w	d0,d2
	lsr.w   #3,d0		; bytes to scroll
	and.w   #$F,d2		; pixels = 0xf - (hpos - (hpos_bytes*8))
	move.w  #$F,d0
	sub.w   d2,d0		; bits to delay

	lsl.w	#4,d5
	or.w	d5,d0	

	move.w	d0,copperListScrollPtr
	;; move.w  d0,BPLCON1(a6)	
	
	;; movem.l (sp)+,d0-d6
	rts

ResetAnimPattern:
	lea	animIndex,a0
	move.l	animIndexPatternPtr,a1
	move.l	#7,d0
.loop:
	move.l	(a1)+,(a0)+
	dbra	d0,.loop
	add.l	#8,animIndexPatternPtr
	cmp.l	#$ffffffff,(a1)
	bne	.s1
	lea	animIndexPattern,a0
	move.l	a0,animIndexPatternPtr
.s1:
	rts

ResetDeAnimPattern:
	lea	deAnimIndex,a0
	move.l	deAnimIndexPatternPtr,a1
	move.l	#7,d0
.loop:
	move.l	(a1)+,(a0)+
	dbra	d0,.loop
	add.l	#8,deAnimIndexPatternPtr
	cmp.l	#$ffffffff,(a1)
	bne	.s1
	lea	deAnimIndexPattern,a0
	move.l	a0,deAnimIndexPatternPtr
.s1:
	rts	

RenderNextBackgroundFrame:
	lea	backgroundMap,a2
	move.l	backgroundScrollX,d0
	lsr.l	#BACKGROUND_SCROLL_TILE_INDEX_CONVERT,d0
	and.b	#$fe,d0
	add.l	d0,a2

	cmp.w	#$FFFF,20(a2)
	bne	.skip
	move.l	#0,backgroundScrollX
.skip:
	bsr	RenderBackgroundTile	
	rts
	
RenderNextForegroundFrame:
	lea	map,a2	
	move.l	foregroundScrollX,d0	
	lsr.l   #FOREGROUND_SCROLL_TILE_INDEX_CONVERT,d0
	lsr.l	#1,d0
	and.b   #$f0,d0
	add.l	d0,a2		
	move.l	#FOREGROUND_PLAYAREA_HEIGHT_WORDS-1,d3		; 8 tiles per column
.loop:
	move.l	d3,d2
	bsr	RenderForegroundTile
	bsr	ClearForegroundTile
	jsr	RenderItemSprite	
	add.l	#2,a2
	dbra	d3,.loop
	rts


RenderForegroundTile_NoAnim:
	;; a2 - address of tileIndex
	move.l	foregroundScrollX,d0
	lsr.w	#FOREGROUND_SCROLL_SHIFT_CONVERT,d0		; convert to pixels
	lsr.w   #3,d0		; bytes to scroll
	move.l	foregroundOffscreen,a0
	add.l	d0,a0
	lea 	tilemap,a1	
	add.w	(a2),a1 	; source tile	
	add.l	#(BITPLANE_WIDTH_BYTES*SCREEN_BIT_DEPTH*(256-(16*4))/4)+BITPLANE_WIDTH_BYTES-8,a0
	jsr	BlitTile
	rts	

RenderForegroundTile:
	;; a2 - address of tileIndex
	move.l	foregroundScrollX,d0
	lsr.w	#FOREGROUND_SCROLL_SHIFT_CONVERT,d0		; convert to pixels
	lsr.w   #3,d0		; bytes to scroll
	move.l	foregroundOffscreen,a0
	add.l	d0,a0
	lea 	tilemap,a1	
	add.w	(a2),a1 	; source tile	
	add.l	#(BITPLANE_WIDTH_BYTES*SCREEN_BIT_DEPTH*(256-(16*8)+32)/4)+BITPLANE_WIDTH_BYTES-FOREGROUND_PLAYAREA_RIGHT_MARGIN_BYTES,a0
	lea 	animIndex,a4
	move.l	d2,d1
	lsl.l	#2,d1
	add.l	d1,a4
	move.l	(a4),d1
	lsr.l	#2,d1		; anim scaling (speed)
	cmp.l	#10,d1
	bge	.s1
	add.l	d1,a1
	jsr	BlitTile
	cmp.l	#2,(a4)
	blt	.s2
.s1:
	sub.l	#2,(a4)	
.s2:
	rts
	

ClearForegroundTile:	
	lea 	tilemap,a1		
	move.l	a2,a4
	sub.l	#FOREGROUND_PLAYAREA_WIDTH_WORDS*8,a4
	sub.l	d0,d0
	move.w	(a4),d0
	add.l	d0,a1
	;; 	add.w	(a2,-FOREGROUND_PLAYAREA_WIDTH_WORDS),a1 	; source tile
	lea	map,a3
	add.l	#FOREGROUND_PLAYAREA_WIDTH_WORDS*FOREGROUND_PLAYAREA_HEIGHT_WORDS,a3
	cmp.l	a3,a2		; don't clear until the full play area has scrolled in
	blt	.s3
	sub.l	#FOREGROUND_PLAYAREA_WIDTH_WORDS,a0
	lea 	deAnimIndex,a4
	move.l	d2,d1
	lsl.l	#2,d1
	add.l	d1,a4
	move.l	(a4),d1
	lsr.l	#2,d1		; anim scaling (speed)
	cmp.l	#10,d1
	bge	.s1	
	add.l	d1,a1
	add.l	#2,(a4)	
	bra	.s2
.s1:
	add.w	#11520,a1 	; source tile	
.s2:
	jsr	BlitTile
.s3:
	rts

	
RenderBackgroundTile:	
	;; a2 - map
	move.l	backgroundScrollX,d0
	lsr.w	#BACKGROUND_SCROLL_SHIFT_CONVERT,d0 ; convert to pixels
	lsr.w   #3,d0		; bytes to scroll
	move.l	backgroundOffscreen,a0
	add.l	d0,a0
	lea 	backgroundTilemap,a1	
	add.l	#BITPLANE_WIDTH_BYTES-2,a0 ; dest
	add.w	(a2),a1 	; source tile
	move.l	backgroundScrollX,d2
	lsr.b	#BACKGROUND_SCROLL_SHIFT_CONVERT,d2		; convert to pixels
	andi.w	#$f,d2		; find the shift component		
	jsr	BlitTile
	rts	



Level3InterruptHandler:
	movem.l	d0-a6,-(sp)
	lea	CUSTOM,a6
.checkVerticalBlank:
	move.w	INTREQR(a6),d0
	and.w	#INTF_VERTB,d0	
	beq	.checkCopper

.verticalBlank:
	move.w	#INTF_VERTB,INTREQ(a6)	; clear interrupt bit	
	add.l	#1,verticalBlankCount
	jsr SetupSpriteData
.checkCopper:
	move.w	INTREQR(a6),d0
	and.w	#INTF_COPER,d0	
	beq.s	.interruptComplete
.copperInterrupt:
	move.w	#INTF_COPER,INTREQ(a6)	; clear interrupt bit	
	
.interruptComplete:
	movem.l	(sp)+,d0-a6
	rte	


copperList:

panelCopperListBpl1Ptr:	
	dc.w	BPL1PTL,0
	dc.w	BPL1PTH,0
	dc.w	BPL2PTL,0
	dc.w	BPL2PTH,0
	dc.w	BPL3PTL,0
	dc.w	BPL3PTH,0
	dc.w	BPL4PTL,0
	dc.w	BPL4PTH,0		
	dc.w    BPLCON1,0
	dc.w	DDFSTRT,(RASTER_X_START/2-SCREEN_RES)
	dc.w	DDFSTOP,(RASTER_X_START/2-SCREEN_RES)+(8*((SCREEN_WIDTH/16)-1))
	dc.w	BPLCON0,(4<<12)|COLOR_ON ; 4 bit planes
	dc.w	BPL1MOD,SCREEN_WIDTH_BYTES*4-SCREEN_WIDTH_BYTES
	dc.w	BPL2MOD,SCREEN_WIDTH_BYTES*4-SCREEN_WIDTH_BYTES
	include "out/panel-copper-list.s"
	dc.W    $5bd1,$fffe


	dc.w	BPL1MOD,BITPLANE_WIDTH_BYTES*SCREEN_BIT_DEPTH-SCREEN_WIDTH_BYTES-2
	dc.w	BPL2MOD,BITPLANE_WIDTH_BYTES*SCREEN_BIT_DEPTH-SCREEN_WIDTH_BYTES-2	
	
	dc.w    BPLCON1
copperListScrollPtr:	
	dc.w	0
copperListBpl1Ptr:
	;; this is where bitplanes are assigned to playfields
	;; http://amigadev.elowar.com/read/ADCD_2.1/Hardware_Manual_guide/node0079.html
	;; 3 bitplanes per playfield, playfield1 gets bitplanes 1,3,5
	dc.w	BPL1PTL,0
	dc.w	BPL1PTH,0
	dc.w	BPL3PTL,0
	dc.w	BPL3PTH,0
	dc.w	BPL5PTL,0
	dc.w	BPL5PTH,0

copperListBpl2Ptr:
	;; 3 bitplanes per playfield, playfield2 gets bitplanes 2,4,6
	dc.w	BPL2PTL,0
	dc.w	BPL2PTH,0
	dc.w	BPL4PTL,0
	dc.w	BPL4PTH,0
	dc.w	BPL6PTL,0
	dc.w	BPL6PTH,0

	dc.w	DDFSTRT,(RASTER_X_START/2-SCREEN_RES)-8 ; -8 for extra scrolling word
	dc.w	DDFSTOP,(RASTER_X_START/2-SCREEN_RES)+(8*((SCREEN_WIDTH/16)-1))	
	dc.w	BPLCON0,(SCREEN_BIT_DEPTH*2<<12)|COLOR_ON|DBLPF	

tileMapCopperPalettePtr:	
	include "tilemap-copper-list.s"

	dc.l	$fffffffe	

InstallSpriteColorPalette:
	include "out/sprite_pig_up-palette.s"
	include "out/sprite_coin1-palette.s"
	rts

InstallColorPalette:
	lea	tileMapCopperPalettePtr,a1
	lea	tilemapPalette,a0
	add.l	#2,a1
	move.l	#15,d0
.loop:
	move.w	(a0),(a1)
	add.l	#2,a0
	add.l	#4,a1	
	dbra	d0,.loop
	rts
	
InstallGreyPalette:
	lea	tileMapCopperPalettePtr,a1
	lea	greyPalette,a0
	add.l	#2,a1
	move.l	#15,d0
.loop:
	move.w	(a0),(a1)
	add.l	#2,a0
	add.l	#4,a1	
	dbra	d0,.loop
	rts


InstallNextGreyPalette:
	lea	tileMapCopperPalettePtr,a1	
	move.l	fadePtr,a0
	lea	fadeComplete,a2
	cmp.l	a2,a0
	bge	.done
	add.l	#2,a1
	move.l	#15,d0
.loop:
	move.w	(a0),(a1)
	add.l	#2,a0
	add.l	#4,a1	
	dbra	d0,.loop
	move.l	frameCount,d0
	lsr.l	#1,d0
	btst.l	#0,d0
	beq	.done
	add.l	#16*2,fadePtr
.done
	rts	

InstallPalette:
	include	"out/tilemap-palette.s"
	rts

foregroundOnscreen:
	dc.l	foregroundBitplanes1
foregroundOffscreen:
	dc.l	foregroundBitplanes2
backgroundOnscreen:
	dc.l	backgroundBitplanes1
backgroundOffscreen:
	dc.l	backgroundBitplanes1
tilemap:
	incbin "out/foreground.bin"
backgroundTilemap:
	incbin "out/background.bin"

panel:
	incbin "out/panel.bin"
map:
	include "out/foreground-map.s"
	dc.w	$FFFF
itemsMap:
	include "out/items-indexes.s"
	dc.w	$FFFF
mapSize:
	dc.l	itemsMap-map
	
backgroundMap:
	include "out/background-map.s"
	dc.w	$FFFF
foregroundScrollPixels:
	dc.l	FOREGROUND_SCROLL_PIXELS	
foregroundScrollX:
	dc.l	0
backgroundScrollX:
	dc.l	0
frameCount:
	dc.l	0
verticalBlankCount:
	dc.l	0
moving:
	dc.w	0

fadePtr:
	dc.l	fade

animIndex:
	ds.l	16,0
deAnimIndex:
	ds.l	16,0	

animIndexPatternPtr:
	dc.l	animIndexPattern
animIndexPattern:
	dc.l	0
	dc.l	8*4
	dc.l	10*4
	dc.l	16*4
	dc.l	12*4
	dc.l	14*4
	dc.l	16*4
	dc.l	0
	dc.l	0
	dc.l	16*4
	dc.l	10*4
	dc.l	6*4
	dc.l	2*4
	dc.l	16*4
	dc.l	14*4
	dc.l	0
	dc.l	0
	dc.l	8*4
	dc.l	10*4
	dc.l	16*4
	dc.l	12*4
	dc.l	14*4
	dc.l	16*4
	dc.l	0
	dc.l	0
	dc.l	16*4
	dc.l	10*4
	dc.l	8*4
	dc.l	12*4
	dc.l	4*4
	dc.l	12*4
	dc.l	0
	dc.l	$ffffffff

deAnimIndexPatternPtr:
	dc.l	deAnimIndexPattern
deAnimIndexPattern:
	dc.l	0
	dc.l	0*4
	dc.l	2*4
	dc.l	4*4
	dc.l	2*4
	dc.l	6*4
	dc.l	2*4
	dc.l	0
	dc.l	0
	dc.l	8*4
	dc.l	4*4
	dc.l	6*4
	dc.l	2*4
	dc.l	4*4
	dc.l	2*4
	dc.l	0
	dc.l	0
	dc.l	0*4
	dc.l	4*4
	dc.l	2*4
	dc.l	4*4
	dc.l	2*4
	dc.l	6*4
	dc.l	0
	dc.l	0
	dc.l	6*4
	dc.l	0*4
	dc.l	2*4
	dc.l	2*4
	dc.l	8*4
	dc.l	2*4
	dc.l	0	
	dc.l	$ffffffff	

greyPalette:
	include "tilemap-grey-table.s"

tilemapPalette:
	include "tilemap-palette-table.s"	

fade:
	include "fade.s"
	
	section .bss
foregroundBitplanes1:
	ds.b	IMAGESIZE*3
foregroundBitplanes2:
	ds.b	IMAGESIZE*3

backgroundBitplanes1:
	ds.b	IMAGESIZE*2

startUserstack:
	ds.b	$1000		; size of stack
userstack:

	end