/*
**
**	reworking old overstrike ascii art
**
**	made for Arexx under amigaOs, but should be easy to change into something
**	regina rexx can understand, its only the filehandling functions that differs 
**	from arexx and regina iso rexx 
**
**	Jacob Dahl Pind
*/

parse arg filename

/* path and name of layers */
pathname="ram:layer."

/*
** main 
*/

/* counter for maximum amounts of overstriks */
max_os=0

/* loop counter of overstrikes */
os=0

/* <CR><LF> */
fin=""


/* count overstrik layers */
IF open(fh,filename,"READ") THEN DO
	DO UNTIL EOF(fh)

	line=readln(fh)

	command=Left(line,1)

		select 
			when command="+" THEN call count_os
			otherwise 
						os=0
		end
	
	end
close(fh)
end

say "maxium of overstrik layers : " max_os

/* build layer files for writning */
call build_layerfiles

/* clean layers */
call clean_layers

lloop=0

/*split into layers now*/
IF open(fh,filename,"READ") THEN DO
	DO UNTIL EOF(fh)

	line=readln(fh)
	command=Left(line,1)
	size=length(line)
	outline=right(line,(size-1))


		select 
			when command=" " THEN call normal
			when command="0" THEN call ds
			when command="1" THEN call np
			when command="+" THEN call overstrike
		end
	end
close(fh)
end

exit

/* sub routines */

build_layerfiles:

DO loop=0 TO max_os
layerfile=pathname||loop
		IF open(fh2,layerfile,"WRITE") THEN DO
			close(fh2)
		END
END

return

count_os:
os=os+1
/* check if we have reached a new record of overstriks */
if os > max_os THEN max_os = os
return

overstrike:
os=os+1

/* set the right layer to contain the outline */
layer.os=outline

return

normal:
/* reset os counter to 0 */
os=0

layer.os=outline

	do loop=0 to max_os
		layerfile=pathname||loop
		IF open(fh2,layerfile,"APPEND") THEN DO
			writeLN(fh2,layer.loop)
			close(fh2)
		END
	end

	lloop=lloop+1
	say "line :"lloop

return

ds:
return

np:
exit
return

clean_layers:
/* set all layers to empty lines */
	do loop=0 to max_os

		layer.loop=fin
	END
return

..
.