( 
	app/left : text editor

	TODO
		- Follow cursor when moving out of the screen
		- Moving should using selection instead of position
		- Slowdown ctrl keys
		- Save/Load
		- Select blank lines
		- Real scrolling distance
		- page up/down move with ctrl+arrow
		- Select entire line by clicking line number
		- Syntax highlight?
		- Double-click select word
		- Right-click find next instance of selection
		- Mouse block selection
		- Copy/Cut/Paste
		- x scroll
)

&Console    { pad 8 stdio 1 }
&Screen 	{ width 2 height 2 pad 4 x 2 y 2 color 1 }
&Sprite 	{ pad 8 x 2 y 2 addr 2 color 1 }
&Controller { buttons 1 }
&Keyboard 	{ key 1 }
&Mouse  	{ x 2 y 2 state 1 chord 1 xt 1 yt 1 }
&File       { pad 8 name 2 length 2 load 2 save 2 }

&Document   { eof 2 body 8000 }

&Range2d 	{ from 2 to 2 }
&Point2d 	{ x 2 y 2 }
&Label2d 	{ x 2 y 2 color 1 addr 2 }
&Textarea2d { x1 2 y1 2 x2 2 y2 2 addr 2 cursor 1 }

;selection Range2d
;pt Point2d ;mouse Point2d ;position Point2d ;scroll Point2d
;textarea Textarea2d
;label Label2d
;j 2 ;addr 2

|0100 @RESET
	
	( load file )
	,filepath ,load-file JSR

	( place textarea )
	#0018 =textarea.x1 ~dev/screen.height #0008 SUB2 =textarea.y2

	,select JSR
	,redraw JSR

BRK

@FRAME
		
	( ctrl )

	,ctrl-end ~dev/ctrl #00 EQU JMP? POP2

		,no-ctrl-down ~dev/ctrl #04 ROR #01 NEQ JMP? POP2
			,move-up JSR	
			,clamp-selection JSR ,redraw JSR ,ctrl-end JMP
		@no-ctrl-down
		,no-ctrl-up ~dev/ctrl #04 ROR #02 NEQ JMP? POP2
			,get-position JSR ~position.y #0001 SUB2 =position.y ,select JSR
			,clamp-selection JSR ,redraw JSR ,ctrl-end JMP
		@no-ctrl-up
		,no-ctrl-left ~dev/ctrl #40 NEQ JMP? POP2
			~selection.from #0001 SUB2 DUP2 =selection.from =selection.to
			,clamp-selection JSR ,redraw JSR ,ctrl-end JMP
		@no-ctrl-left
		,no-ctrl-right ~dev/ctrl #80 NEQ JMP? POP2
			~selection.from #0001 ADD2 DUP2 =selection.from =selection.to
			,clamp-selection JSR ,redraw JSR ,ctrl-end JMP
		@no-ctrl-right
		( alt )
		,no-alt ~dev/ctrl #0f AND #02 NEQ JMP? POP2
			,no-aleft ~dev/ctrl #04 ROR #04 NEQ JMP? POP2
				~selection.to #0001 SUB2 =selection.to
				,clamp-selection JSR ,redraw JSR ,ctrl-end JMP
			@no-aleft
			,no-aright ~dev/ctrl #04 ROR #08 NEQ JMP? POP2
				~selection.to #0001 ADD2 =selection.to
				,clamp-selection JSR ,redraw JSR ,ctrl-end JMP
			@no-aright
		@no-alt
		( ctrl )
		,no-ctrl ~dev/ctrl #0f AND #01 NEQ JMP? POP2
			,no-cleft ~dev/ctrl #04 ROR #04 NEQ JMP? POP2
				,find-linestart JSR #0001 ADD2 DUP2 =selection.from =selection.to
				,clamp-selection JSR ,redraw JSR ,ctrl-end JMP
			@no-cleft
			,no-cright ~dev/ctrl #04 ROR #08 NEQ JMP? POP2
				,find-lineend JSR #0001 SUB2 DUP2 =selection.from =selection.to
				,clamp-selection JSR ,redraw JSR ,ctrl-end JMP
			@no-cright
		@no-ctrl

	@ctrl-end

	( keys )

	,keys-end ~dev/key #00 EQU JMP? POP2

		,no-backspace ~dev/key #08 NEQ JMP? POP2
			( erase )
			~selection.from #0001 SUB2 =selection.from
			~selection.from #0001 ADD2 =selection.to
			~document.eof #0001 SUB2 =document.eof
			~selection.from =j ( start -> end )
			@erase-loop
				~j #0001 ADD2 LDR ~j STR
				( incr ) ~j #0001 ADD2 =j
				,erase-loop ~j ~document.eof LTH2 JMP? POP2
			( release ) #00 =dev/key
			,redraw JSR
			,keys-end JMP
		@no-backspace

		( insert )
		~document.eof #0001 ADD2 =document.eof
		~document.eof =j ( end -> start )
		@insert-loop
			~j #0001 SUB2 LDR ~j STR
			( decr ) ~j #0001 SUB2 =j
			,insert-loop ~j ~selection.from GTH2 JMP? POP2
		~dev/key ~selection.from STR
		~selection.from #0001 ADD2 =selection.from
		~selection.from #0001 ADD2 =selection.to
		( release ) #00 =dev/key
		,redraw JSR

	@keys-end

	( mouse )

	,click-end ~dev/mouse.state #00 EQU JMP? POP2

		( scrollbar )
		,no-click-scroll ~dev/mouse.x ~dev/screen.width #0008 SUB2 LTH2 JMP? POP2

			,no-click-scroll-up ~dev/mouse.y #0008 GTH2 JMP? POP2
				,scroll-up JSR
				,click-end JMP
			@no-click-scroll-up 

			,no-click-scroll-down ~dev/mouse.y ~dev/screen.height #0008 SUB2 LTH2 JMP? POP2
				,scroll-down JSR
				,click-end JMP
			@no-click-scroll-down 

			( on scrollbar )
			~dev/mouse.y #0008 SUB2 =scroll.y
			,redraw JSR
			,click-end JMP

		@no-click-scroll

		( select body )
		~dev/mouse.y #0008 DIV2 ~scroll.y ADD2 =position.y
		~dev/mouse.x ~textarea.x1 SUB2 #0008 ADD2 #0008 DIV2  =position.x

		,select JSR
		,redraw JSR

	@click-end

	,draw-cursor JSR

BRK 

@load-file ( path )

	=dev/file.name #8000 =dev/file.length ,document.body =dev/file.load

	( get file length )
	,document.body =document.eof
	@load-file-loop
		( incr ) ~document.eof #0001 ADD2 =document.eof
	,load-file-loop ~document.eof LDR #00 NEQ JMP? POP2

RTS

@clamp-selection

	~selection.from ~selection.to LTH2 RTS?
	~selection.from #0001 ADD2 =selection.to

RTS

@scroll-up
	
	( clamp ) ~scroll.y #0000 EQU2 RTS?
	( decr ) ~scroll.y #0001 SUB2 =scroll.y
	,redraw JSR

RTS

@scroll-down
		
	( incr ) ~scroll.y #0001 ADD2 =scroll.y
	,redraw JSR

RTS

@find-linestart

	~selection.from =j
	@goto-linestart-loop
		~j
		~j LDR #0a EQU RTS?
		~j LDR #0d EQU RTS?
		POP2
		( decr ) ~j #0001 SUB2 =j
	,goto-linestart-loop ~j LDR #00 NEQ JMP? POP2

RTS

@find-lineend

	~selection.from =j
	@goto-lineend-loop
		( incr ) ~j #0001 ADD2 =j
		~j
		~j LDR #0a EQU RTS?
		~j LDR #0d EQU RTS?
		POP2
	,goto-lineend-loop ~j LDR #00 NEQ JMP? POP2

RTS

@move-up
	
	,find-linestart JSR =selection.from
	,find-lineend JSR =selection.to

RTS

@get-position ( selection -> position )

	,document.body =j #0000 =position.x #0000 =position.y

	@get-position-loop

		,no-position-space ~j LDR #0a NEQ ~j LDR #0d NEQ #0101 EQU2 JMP? POP2
			( incr ) ~position.y #0001 ADD2 =position.y
			#0000 =position.x
		@no-position-space

		,no-position-reached ~j ~selection.from NEQ2 JMP? POP2
			RTS
		@no-position-reached

		( incr ) ~position.x #0001 ADD2 =position.x
		( incr ) ~j #0001 ADD2 =j
	,get-position-loop ~j LDR #00 NEQ JMP? POP2

RTS

@select ( position -> selection )
	
	,document.body =selection.from #0000 =pt.x #0000 =pt.y

	@select-loop

		,no-space ~selection.from LDR #0a NEQ ~selection.from LDR #0d NEQ #0101 EQU2 JMP? POP2
			( incr ) ~pt.y #0001 ADD2 =pt.y
			#0000 =pt.x
		@no-space

		,no-reached ~pt.y ~position.y #0001 SUB2 GTH2 ~pt.x ~position.x #0001 SUB2 GTH2 #0101 NEQ2 JMP? POP2
			~selection.from #0001 ADD2 =selection.to
			RTS
		@no-reached

		( incr ) ~pt.x #0001 ADD2 =pt.x
		( incr ) ~selection.from #0001 ADD2 =selection.from
	,select-loop ~selection.from LDR #00 NEQ JMP? POP2

RTS

@redraw

	,draw-lines JSR

	,draw-textarea JSR
	,draw-scrollbar JSR
	,draw-titlebar JSR

	( save/load icons )

	~dev/screen.height #0008 SUB2 =dev/sprite.y

	~dev/screen.width #0018 SUB2 =dev/sprite.x
	,load_icn =dev/sprite.addr
	#02 =dev/sprite.color

	~dev/screen.width #0010 SUB2 =dev/sprite.x
	,save_icn =dev/sprite.addr
	#02 =dev/sprite.color

RTS

@draw-lines
	
	#0000 =j
	#0000 =dev/sprite.x
	#0000 =dev/sprite.y

	@draw-lines-loop

		#0000 =dev/sprite.x
		
		~scroll.y ~j ADD2 =addr
		,font_hex #00 ,addr #0001 ADD2 LDR #f0 AND #04 ROR #08 MUL ADD2 =dev/sprite.addr
		( draw ) #02 ~addr ~position.y EQU2 ADD =dev/sprite.color
		~dev/sprite.x #0008 ADD2 =dev/sprite.x
		,font_hex #00 ,addr #0001 ADD2 LDR #0f AND #08 MUL ADD2 =dev/sprite.addr
		( draw ) #02 ~addr ~position.y EQU2 ADD =dev/sprite.color
		( incr ) ~j #0001 ADD2 =j
		( incr ) ~dev/sprite.y #0008 ADD2 =dev/sprite.y
		,draw-lines-loop ~j ~dev/screen.height #0008 DIV2 NEQ2 JMP? POP2

RTS

@draw-short ( short )

	=addr
	,font_hex #00 ,addr LDR #f0 AND #04 ROR #08 MUL ADD2 =dev/sprite.addr
	( draw ) #0e =dev/sprite.color
	~dev/sprite.x #0008 ADD2 =dev/sprite.x
	,font_hex #00 ,addr LDR #0f AND #08 MUL ADD2 =dev/sprite.addr
	( draw ) #0e =dev/sprite.color
	~dev/sprite.x #0008 ADD2 =dev/sprite.x
	,font_hex #00 ,addr #0001 ADD2 LDR #f0 AND #04 ROR #08 MUL ADD2 =dev/sprite.addr
	( draw ) #0e =dev/sprite.color
	~dev/sprite.x #0008 ADD2 =dev/sprite.x
	,font_hex #00 ,addr #0001 ADD2 LDR #0f AND #08 MUL ADD2 =dev/sprite.addr
	( draw ) #0e =dev/sprite.color

RTS

@draw-cursor

	~mouse.x ~dev/mouse.x NEQU2
	~mouse.y ~dev/mouse.y NEQU2

	#0000 EQU2 RTS? ( Return if unchanged )

	( clear last cursor )
	~mouse.x =dev/sprite.x
	~mouse.y =dev/sprite.y
	,blank_icn =dev/sprite.addr
	#10 =dev/sprite.color

	( record mouse positions )
	~dev/mouse.x =mouse.x 
	~dev/mouse.y =mouse.y

	( draw new cursor )
	~mouse.x =dev/sprite.x
	~mouse.y =dev/sprite.y
	,cursor_icn =dev/sprite.addr
	#13 =dev/sprite.color

RTS

@draw-textarea ( x y color addr )
	
	,document.body =textarea.addr
 
	( scroll to position )
	#0000 =j ( j is linebreaks )
	@find-scroll-offset
		,find-scroll-offset-end ~scroll.y ~j EQU2 JMP? POP2
		,no-break ~textarea.addr LDR #0a NEQ ~textarea.addr LDR #0d NEQ #0101 EQU2 JMP? POP2
			( incr ) ~j #0001 ADD2 =j
		@no-break
		( incr ) ~textarea.addr #0001 ADD2 =textarea.addr
	,find-scroll-offset ~textarea.addr LDR #00 NEQ JMP? POP2
	@find-scroll-offset-end

	~textarea.addr #0000 ADD2 =textarea.addr
	#0000 =dev/sprite.y
	~textarea.addr =j

	#0018 =dev/sprite.x

	@draw-textarea-loop

		,no-linebreak ~j LDR #0a NEQ ~j LDR #0d NEQ #0101 EQU2 JMP? POP2
			( draw linebreak )
			,linebreak_icn =dev/sprite.addr
			#02 =dev/sprite.color

			( fill clear )
			@fill-clear
				( incr ) ~dev/sprite.x #0008 ADD2 =dev/sprite.x
				,font =dev/sprite.addr
				#01 =dev/sprite.color
				,fill-clear ~dev/sprite.x ~dev/screen.width #0008 SUB2 LTH2 JMP? POP2
			#0010 =dev/sprite.x
			( incr ) ~dev/sprite.y #0008 ADD2 =dev/sprite.y
		@no-linebreak

		,draw-textarea-end ~dev/sprite.y ~dev/screen.height #0010 SUB2 GTH2 JMP? POP2

		( get character )
		,font #00 ~j LDR #20 SUB #0008 MUL2 ADD2 =dev/sprite.addr

		( draw ) #01 
		~j ~selection.from #0001 SUB2 GTH2 
		~j ~selection.to LTH2 #0101 EQU2
		#05 MUL ADD =dev/sprite.color

		( incr ) ~j #0001 ADD2 =j
		( incr ) ~dev/sprite.x #0008 ADD2 =dev/sprite.x

	,draw-textarea-loop ~j LDR #00 NEQ JMP? POP2

	@draw-textarea-end

RTS

@draw-scrollbar
		
	~dev/screen.width #0008 SUB2 =dev/sprite.x
	#0000 =dev/sprite.y
	,scrollbar_bg =dev/sprite.addr

	@draw-scrollbar-loop
	( draw ) #08 =dev/sprite.color
	( incr ) ~dev/sprite.y #0008 ADD2 =dev/sprite.y
	,draw-scrollbar-loop ~dev/sprite.y ~dev/screen.height LTH2 JMP? POP2

	#0000 =dev/sprite.y
	,arrowup_icn =dev/sprite.addr
	( draw ) #08 =dev/sprite.color

	( at )
	~scroll.y #0008 ADD2 =dev/sprite.y
	,scrollbar_fg =dev/sprite.addr
	( draw ) #08 =dev/sprite.color

	~dev/screen.height #0008 SUB2 =dev/sprite.y
	,arrowdown_icn =dev/sprite.addr
	( draw ) #08 =dev/sprite.color

RTS

@draw-titlebar
	
	#0018 ~dev/screen.height #0008 SUB2 #09 ,filepath 

	( load ) =label.addr =label.color =dev/sprite.y =dev/sprite.x 
	~label.addr
	@draw-titlebar-loop
		( draw ) DUP2 LDR #00 SWP #20 SUB #0008 MUL2 ,font ADD2 =dev/sprite.addr ~label.color =dev/sprite.color
		( incr ) #0001 ADD2
		( incr ) ~dev/sprite.x #0008 ADD2 =dev/sprite.x
		DUP2 LDR #00 NEQ ,draw-titlebar-loop ROT JMP? POP2
	POP2

	( selection )
	~selection.from ,document.body SUB2 ,draw-short JSR

	( length )
	~dev/screen.width #0040 SUB2 =dev/sprite.x
	~document.eof ,document.body SUB2 ,draw-short JSR

RTS

@font_hex ( 0-F TODO: should pull from @font instead.. ) 
[
	003c 464a 5262 3c00 0018 0808 0808 1c00
	003c 4202 3c40 7e00 003c 421c 0242 3c00
	000c 1424 447e 0400 007e 407c 0242 3c00
	003c 407c 4242 3c00 007e 0204 0810 1000
	003c 423c 4242 3c00 003c 4242 3e02 3c00
	003c 4242 7e42 4200 007c 427c 4242 7c00 
	003c 4240 4042 3c00 007c 4242 4242 7c00 
	007e 4078 4040 7e00 007e 4078 4040 4000
]

@font ( specter8-frag font ) 
[
	0000 0000 0000 0000 0008 0808 0800 0800
	0014 1400 0000 0000 0024 7e24 247e 2400
	0008 1e28 1c0a 3c08 0000 2204 0810 2200
	0030 4832 4c44 3a00 0008 1000 0000 0000
	0004 0808 0808 0400 0020 1010 1010 2000
	0000 2214 0814 2200 0000 0808 3e08 0800
	0000 0000 0000 0810 0000 0000 3e00 0000
	0000 0000 0000 0800 0000 0204 0810 2000
	003c 464a 5262 3c00 0018 0808 0808 1c00
	003c 4202 3c40 7e00 003c 421c 0242 3c00
	000c 1424 447e 0400 007e 407c 0242 3c00
	003c 407c 4242 3c00 007e 0204 0810 1000
	003c 423c 4242 3c00 003c 4242 3e02 3c00
	0000 0010 0000 1000 0000 1000 0010 1020
	0000 0810 2010 0800 0000 003e 003e 0000
	0000 1008 0408 1000 003c 420c 1000 1000
	003c 4232 4a42 3c00 003c 4242 7e42 4200
	007c 427c 4242 7c00 003c 4240 4042 3c00
	007c 4242 4242 7c00 007e 4078 4040 7e00
	007e 4078 4040 4000 003c 4240 4642 3c00
	0042 427e 4242 4200 001c 0808 0808 1c00
	007e 0202 0242 3c00 0042 4478 4442 4200
	0040 4040 4040 7e00 0042 665a 4242 4200
	0042 6252 4a46 4200 003c 4242 4242 3c00
	007c 4242 7c40 4000 003c 4242 4244 3a00
	007c 4242 7c44 4200 003e 403c 0242 3c00
	007e 0808 0808 1000 0042 4242 4244 3a00
	0042 4242 4224 1800 0042 4242 5a66 4200
	0042 423c 4242 4200 0042 423e 0242 3c00
	007e 020c 3040 7e00 000c 0808 0808 0c00
	0040 2010 0804 0200 0030 1010 1010 3000
	0008 1400 0000 0000 0000 0000 0000 7e00
	0008 0400 0000 0000 0000 3c02 3e42 3a00
	0040 407c 4242 7c00 0000 3c42 4042 3c00
	0002 023e 4242 3e00 0000 3c42 7e40 3e00
	0000 3e40 7840 4000 0000 3c42 3e02 3c00
	0040 405c 6242 4200 0008 0018 0808 0400
	0008 0018 0808 4830 0040 4244 7844 4200
	0010 1010 1010 0c00 0000 6c52 5252 5200
	0000 5c62 4242 4200 0000 3c42 4242 3c00
	0000 7c42 427c 4040 0000 3e42 423e 0202
	0000 5c62 4040 4000 0000 3e40 3c02 7c00
	0008 7e08 0808 1000 0000 4242 4244 3a00
	0000 4242 4224 1800 0000 5252 5252 2e00
	0000 4224 1824 4200 0000 4242 3e02 7c00
	0000 7e02 3c40 7e00 000c 0810 1008 0c00
	0008 0808 0808 0800 0030 1008 0810 3000
	0000 0032 4c00 0000 3c42 99a1 a199 423c

]

@linebreak_icn [ 003e 7474 3414 1400 ]
@blank_icn     [ 0000 0000 0000 0000 ]
@cursor_icn    [ 80c0 e0f0 f8e0 1000 ]
@scrollbar_bg  [ aa55 aa55 aa55 aa55 ]
@scrollbar_fg  [ ffff ffff ffff ffff ]
@arrowup_icn   [ 0010 387c fe10 1010 ]
@arrowdown_icn [ 0010 1010 fe7c 3810 ]
@load_icn      [ feaa d6aa d4aa f400 ]
@save_icn      [ fe82 8282 848a f400 ]
@filepath1     [ test.txt 00 ]
@filepath      [ projects/software/left.usm 00 ]

|4000 ;document Document

|d000 @ERROR BRK 

|FF00 ;dev/console Console
|FF10 ;dev/screen  Screen
|FF20 ;dev/sprite  Sprite
|FF30 ;dev/ctrl    Controller
|FF40 ;dev/key     Keyboard
|FF50 ;dev/mouse   Mouse
|FF60 ;dev/file    File

|FFF0 .RESET .FRAME .ERROR ( vectors )
|FFF8 [ 40ff c09f a09f ] ( palette )