#include "crash82.inc"
.db "Mr. Happy :)",0

BOXX = TEXT_MEM
BOXY = TEXT_MEM+1

BEGIN:
	ROM_CALL(CLEARLCD)
	call CR_GRBCopy ;Clears Graph Buffer
	ld a,40 ;Initial X & Y coords
	ld (BOXX),a ;of box
	ld a,55
	ld (BOXY),a
	jp moveloop

moveloop:
	call putbox ;Call put box
	jp getky

getky: ;routine getkey
	ld a,0ffh
	out (1),a
	ld a,0feh
	out (1),a
	in a,(1)
	cp 253 ;Is key Left?
	jp z,left ;Goto Left
	cp 251 ;Is the key right?
	jp z,right ;Goto Right
	cp 254 ;Is key Up?
	jp z,up ;Goto up
	cp 247 ;Is the key down?
	jp z,down ;Goto Down
	ld a,0ffh
	out (1),a 
	ld a,0fdh
	out (1),a
	in a,(1)
	cp 191 ;Is the key clear?
	jp z,quit ;If so, goto quit
	jp getky ;No key ? Go back to getkey!

left:
	call putbox       
	ld a,(BOXX) ;Load XCoord Variable into A
	dec a ;Decrease A
	cp 0
	jp z,BOOM
	ld (BOXX),a ;Load back into BOXX
	jp moveloop ;goto moveloop

right:       
	call putbox       
	ld a,(BOXX) ;Load XCoord Variable into A
	inc a ;Increase A
	cp 86
	jp z,BOOM
	ld (BOXX),a ;Load back into BOXX
	jp moveloop ;goto moveloop

down:       
	call putbox
	ld a,(BOXY) ;Load YCoord Variable into A
	dec a ;Decrease A
	cp 0
	jp z,BOOM
	ld (BOXY),a ;Load back into BOXY
	jp moveloop ;goto moveloop
               
up:       
	call putbox       
	ld a,(BOXY) ;Load YCoord Variable into A
	inc a ;Increase A
	cp 95
	jp z,BOOM
	ld (BOXY),a ;Load back into BOXY
	jp moveloop ;goto moveloop
                
putbox:       
	ld a,(BOXY)       
	ld e,a ;Stores 55 -> e , where e = y
	ld a,(BOXX) ;Stores 40 -> x , where x = x
	ld bc,box ;Load sprite name to bc
	call SPRXOR ;Call movax' Sprite Routine 
	call CR_GRBCopy
	ret

BOOM:       
	ld a,(BOXY)       
	ld e,a ;Stores 55 -> e , where e = y
	ld a,(BOXX) ;Stores 40 -> x , where x = x
	ld bc,boompic ;Load sprite name to bc
	call SPRXOR ;Call movax' Sprite Routine 
	call CR_GRBCopy
	jp DONE


                                
quit:       
	ROM_CALL(CLEARLCD)
	call _grbufclr
	ret

_grbufclr:
  	ld 	hl,$88B8
  	ld 	de,$88B9
  	ld 	bc,768
  	ld 	(hl),0
  	ldir
  	ret
SPRXOR:

        push    bc              ; Save sprite address

;лллл   Calculate the address in graphbuf   лллл

        ld      hl,0            ; Do y*12
        ld      d,0
        add     hl,de
        add     hl,de
        add     hl,de
        add     hl,hl
        add     hl,hl

        ld      d,0             ; Do x/8
        ld      e,a
        srl     e
        srl     e
        srl     e
        add     hl,de

        ld      de,$88B8
        add     hl,de           ; Add address to graphbuf

        ld      b,00000111b     ; Get the remainder of x/8
        and     b
        cp      0               ; Is this sprite aligned to 8*n,y?
        jp      z,ALIGN


;лллл   Non aligned sprite blit starts here   лллл

        pop     ix              ; ix->sprite
        ld      d,a             ; d=how many bits to shift each line

        ld      e,8             ; Line loop
LILOP:  ld      b,(ix+0)        ; Get sprite data

        ld      c,0             ; Shift loop
        push    de
SHLOP:  srl     b
        rr      c
        dec     d
        jp      nz,SHLOP
        pop     de

        ld      a,b             ; Write line to graphbuf
        xor     (hl)
        ld      (hl),a
        inc     hl
        ld      a,c
        xor     (hl)
        ld      (hl),a

        ld      bc,11           ; Calculate next line address
        add     hl,bc
        inc     ix              ; Inc spritepointer

        dec     e
        jp      nz,LILOP        ; Next line

        jp      DONE1


;лллл   Aligned sprite blit starts here   лллл

ALIGN:                          ; Blit an aligned sprite to graphbuf
        pop     de              ; de->sprite
        ld      b,8
ALOP1:  ld      a,(de)
        xor     (hl)
        ld      (hl),a
        inc     de
        push    bc
        ld      bc,12
        add     hl,bc
        pop     bc
        djnz    ALOP1

DONE1:
        ret
  
DONE:
	ld a,0ffh
	out (1),a 
	ld a,0fdh
	out (1),a
	in a,(1)
	cp 191 ;Is the key clear?
	jp z,quit ;If so, goto quit
	jp DONE ;No key ? Go back to getkey!


box:       
	.db 11111111b       
	.db 10000001b       
	.db 10100101b
	.db 10000001b       
	.db 10011001b
	.db 11000011b       
	.db 10111101b       
	.db 11111111b 

boompic:
	.db 10101010b
	.db 01010101b
	.db 10101010b
	.db 01010101b
	.db 10101010b
	.db 01010101b
	.db 10101010b
	.db 01010101b