; cmdline.as - process command line from MSX-DOS(2)
; Copyright (C) 2001 ag0ny@ag0ny.com

BDOS		equ	00005h
DTA		equ	00080h

_STROUT		equ	009h

LF		equ	00ah	; Line feed
CR		equ	00dh	; Carriage return

system		macro	func
		ld	c,func
		call	BDOS
		endm

start:		ld	(STACK),sp

		ld	hl,ifile	; Clear FCBs for ifile and ofile
		ld	de,ifile+1
		ld	bc,75
		ld	(hl),0
		ldir

		call	cmdline
		jp	end

; ***************
; * Subroutines *
; ***************

cmdline:	ld	hl,DTA

		ld	a,(hl)		; Read command line size
		or	a
		jp	z,usage

		inc	hl		; First character after the command
					; name is always a space
param:		inc	hl
		ld	a,(hl)

		or	a
		ret	z		; return if no more parameters

		cp	'-'
		jr	nz,param
		inc	hl
		ld	a,(hl)
		cp	'v'		; -v
		jp	z,version
		cp	'i'		; -i <file> or -i<file>
		call	z,inputfile
		cp	'o'		; -o <file> or -o<file>
		call	z,outputfile
		cp	'?'		; -?
		jp	z,usage
		jr	param

inputfile:	push	af
		inc	hl
		ld	de,ifile
		call	parsefile
		pop	af
		ret

outputfile:	push	af
		inc	hl
		ld	de,ofile
		call	parsefile
		pop	af
		ret

; parse filename
; input:	HL -> pointer to start of filename
;		DE -> filename buffer
; note:	removes spaces at the beginning of the pointed string
; note: will return after finding a SPACE or NULL after the filename,
;       so more parameters can be processed from the commandline
;
parsefile:	push	hl
		push	de
		; clear filename buffer
		ld	h,d
		ld	l,e
		ld	(hl),32		; ASCII 32 = SPACE
		inc	de
		ld	bc,10
		ldir
		pop	de
		pop	hl

		ld	(tmpword),de	; because we'll need this address
					; on the .EXT parsing part

		ld	a,(hl)		; return if NULL found
		or	a
		ret	z

pf.2:		cp	' '		; remove space(s) at the beginning
		jr	nz,pf.1
		inc	hl
		ld	a,(hl)
		jr	pf.2

pf.1:		; get main filename part (FFFFFFFF)
		ld	b,8
pf.4:		or	a		; return if NULL found
		ret	z
		cp	' '		; return if SPACE (get next param)
		ret	z
		cp	'.'
		jr	z,pf.3		; point found, process extension

		ld	(de),a		; tests passed, store character
		inc	de
		inc	hl
		ld	a,(hl)
		djnz	pf.4

pf.3:		; get extension (.EXT)
		inc	hl
		ld	a,(hl)

		ld	b,3
		ld	de,(tmpword)	; now DE = start of filename again
		inc	de
		inc	de
		inc	de
		inc	de
		inc	de
		inc	de
		inc	de
		inc	de		; now DE = start of .EXT part

pf.5:		or	a		; return if NULL found
		ret	z
		cp	' '		; return if SPACE (get next param)
		ret	z

		ld	(de),a		; tests passed, store character
		inc	de
		inc	hl
		ld	a,(hl)
		djnz	pf.5

		ret

; print version information
version:	ld	de,msg005
		system	_STROUT
		jp	end

; print program information and usage
usage:		ld	de,msg003
		system	_STROUT
; restore original stack and exit to MSX-DOS(2)
end:		ld	hl,(STACK)
		ld	sp,hl
		ret

; error - display error message pointed by DE followed by usage and exit
error:		system	_STROUT
		ld	de,msg004
		system	_STROUT
		jp	end

ifile:		defs	37	; FCB for input file
ofile:		defs	37	; FCB for output file
ifileon:	defb	0	; Input file specified in commandline?
ofileon:	defb	0	; Output file specified in commandline?
STACK:		defs	2	; Original program stack

tmpword:	defs	2	; Temporary storage place

msg000:		defb	'Input file : $'
msg001:		defb	'Output file: $'
msg002:		defb	'Boolean    : $'
msg003:		defb	'cmdline.as - process command line from MSX-DOS(2)'
		defb	CR,LF
		defb	'Copyright (C) 2001 ag0ny@ag0ny.com',CR,LF,CR,LF
msg004:		defb	'Usage:   cmdline <options> [options]',CR,LF,CR,LF
		defb	' -i <file>    Input file (must be a binary dump of'
		defb	' a ROM or program)',CR,LF
		defb	' -o <file>    Output file. If not present, defaults'
		defb	' to the same name as the',CR,LF
		defb	'              input filename with .HEX extension.'
		defb	CR,LF
		defb	' -v           Print version and exit',CR,LF
		defb	' -?           Print this help message and exit',CR,LF
		defb	'$'
msg005:		defb	'v0.01/20010424',CR,LF,'$'
msgon:		defb	'ON$'
msgoff:		defb	'OFF$'

error000:	defb	'Error: invalid input filename.',CR,LF,CR,LF,'$'
error001:	defb	'Error: (2)',CR,LF,CR,LF,'$'
error002:	defb	'Error: (3)',CR,LF
crlf:		defb	CR,LF,'$'
 <file>    Input file (must be a binary dump of'
		defb	' a ROM or program)',CR,LF
		defb	' -o <file>    Output file. If not present, defaults'
		defb	' to the same name as the',CR,LF
		defb	'              input filename with .HEX extension.'
		defb	CR,LF
		defb	' -v           Print version and exit',CR,LF
		defb	' -?           Print this help message and exit',CR,LF
		defb	'$'
msg005:		defb	'v0.01/20010424',CR,LF,'$'
msgon:		defb	'ON$'
msgoff:		defb	'OFF$'

error000:	defb	'Error: invalid input filename.',CR,LF,CR,LF,'$'
error001:	defb	'Error: (2)',CR,LF,CR,LF,'$'
error002:	defb	'Error: (3)',CR,LF
crlf:		defb	CR,LF,'$'

crlf:		defb	CR,LF,'$'