powers = sequence[int]$[2 ** 1 - 1,
			2 ** 2 - 1,
			2 ** 3 - 1,
			2 ** 4 - 1,
			2 ** 5 - 1,
			2 ** 6 - 1,
			2 ** 7 - 1]

state = oneof[_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10: null]

s0 = state$make__0(nil)
s1 = state$make__1(nil)
s2 = state$make__2(nil)
s3 = state$make__3(nil)
s4 = state$make__4(nil)
s5 = state$make__5(nil)
s6 = state$make__6(nil)
s7 = state$make__7(nil)
s8 = state$make__8(nil)
s9 = state$make__9(nil)
s10 = state$make__10(nil)

as = array[state]
ab = array[_bytevec]
qs = sequence[string]

start_up = proc ()
    prog: string := _get_xjname()
    args: qs := get_argv()
    cbdr: string := x_default(prog, "Border")
       except when not_found: cbdr := "" end
    cfore: string := x_default(prog, "Foreground")
       except when not_found: cfore := "" end
    cback: string := x_default(prog, "Background")
       except when not_found: cback := "" end
    cmous: string := x_default(prog, "Mouse")
       except when not_found: cmous := "" end
    spec: string := ""
    fax: string := ""
    host: string := ""
    for opt: string in qs$elements(args) do
	if string$indexs("-bd=", opt) = 1
	   then cbdr := string$rest(opt, 5)
	 elseif string$indexs("-fg=", opt) = 1
	   then cfore := string$rest(opt, 5)
	 elseif string$indexs("-bg=", opt) = 1
	   then cback := string$rest(opt, 5)
	 elseif string$indexs("-ms=", opt) = 1
	   then cmous := string$rest(opt, 5)
	 elseif opt[1] = '='
	   then spec := opt
	 elseif string$indexc(':', opt) ~= 0
	   then host := opt
	 else fax := opt end
	end
    if string$empty(fax)
       then _chan$puts(_chan$error_output(),
		       "usage: xfax [options] [=<geometry>] [host:vs] file\r\n",
		       false)
	    _chan$puts(_chan$error_output(),
		       "options: -fg=<color> -bg=<color> -bd=<color> -ms=<color>\r\n",
		       false)
	    return
       end
    if string$indexc('.', fax) = 0  cand  string$indexc('/', fax) = 0
       then fax := fax || ".fax" end
    fn: file_name := file_name$parse(fax)
    if ~file_exists(fn)
       then _chan$puts(_chan$error_output(), "file not found\r\n", false)
	    return
       end
    x_display$init(host)
       except when error (why: string):
		   _chan$puts(_chan$error_output(), why || "\r\n", false)
		   return
	      end
    bwidth: int := int$parse(x_default(prog, "BorderWidth"))
       except when not_found, overflow, bad_format: bwidth := 2 end
    forep: int := BlackPixel
    backp: int := WhitePixel
    mousep: int := BlackPixel
    back: x_pixmap := x_display$white()
    bdr: x_pixmap := x_display$black()
    if x_display$cells() > 2
       then if ~string$empty(cbdr)
	       then r, g, b: int := x_parse_color(cbdr)
		    bdr := x_pixmap$tile(x_display$alloc_color(r, g, b))
	       end
	    if ~string$empty(cfore)
	       then r, g, b: int := x_parse_color(cfore)
		    forep := x_display$alloc_color(r, g, b)
		    mousep := forep
	       end
	    if ~string$empty(cback)
	       then r, g, b: int := x_parse_color(cback)
		    backp := x_display$alloc_color(r, g, b)
		    back := x_pixmap$tile(backp)
	       end
	    if ~string$empty(cmous)
	       then r, g, b: int := x_parse_color(cmous)
		    mousep := x_display$alloc_color(r, g, b)
	       end
       end
    defspec: string := "=" || int$unparse(x_display$width() - 2 * bwidth - 2) ||
		       "x" || int$unparse(x_display$height() - 2 * bwidth - 2) ||
		       "+1+1"
			
    w: x_window, w0, h0: int := x_cons(prog, back, bdr, spec, defspec,
				       40, 40, bwidth)
    x_window$map(w)
    w.name := fn.name
    cr: x_cursor := x_cursor$scons(arrow_width, arrow_height,
				   arrow, arrow_mask,
				   backp, mousep,
				   arrow_x, arrow_y, GXcopy)
    w.cursor := cr
    w.input := ButtonPressed + ButtonReleased + ExposeRegion + ExposeCopy
    x_flush()
    lines: ab := defax(fax)
    xidx: int := 1
    yidx: int := 1
    x0: int := 0
    y0: int := 0
    display(w, lines, xidx, yidx, 0, 0, 1726, 1726, forep, backp)
    ev: event := x_input$empty_event()
    while true do
	x_input$deq(ev)
	if ev.kind = ExposeWindow  cor  ev.kind = ExposeRegion
	   then display(w, lines, xidx, yidx, ev.x, ev.y, ev.x0, ev.y0,
			forep, backp)
	 elseif ev.kind = ButtonPressed
	   then x0 := ev.x
		y0 := ev.y
	 elseif ev.kind = ButtonReleased
	   then sx, sy, wd, ht, bw, ms, wk: int, iw: x_window :=
		    x_window$query(w)
		x0 := int$min(int$max(xidx + ((x0 - ev.x) / 16) * 2, 1),
			      int$max(217 - (wd / 16) * 2, 1))
		y0 := int$min(int$max(yidx + y0 - ev.y, 1),
			      int$max(ab$size(lines) - ht + 1, 1))
		x: int := (xidx - x0) * 8
		y: int := yidx - y0
		x_window$move_area(w, 0, 0, wd, ht, x,  y)
		if x >= 0  cand  y >= 0
		   then display(w, lines, x0, y0, 0, 0, wd, y, forep, backp)
			display(w, lines, x0, y0, 0, y, x, ht, forep, backp)
		 elseif x >= 0  cand  y < 0
		   then display(w, lines, x0, y0, 0, 0, x, ht, forep, backp)
			display(w, lines, x0, y0, x, ht + y, wd, -y,
				forep, backp)
		 elseif y >= 0
		   then display(w, lines, x0, y0, 0, 0, wd, y, forep, backp)
			display(w, lines, x0, y0, wd + x, y, -x, ht - y,
				forep, backp)
		 else display(w, lines, x0, y0, 0, ht + y, wd, -y,
			      forep, backp)
		      display(w, lines, x0, y0, wd + x, 0, -x, ht + y,
			      forep, backp)
		 end
		xidx := x0
		yidx := y0
		x0 := (xidx - 1) * 8
		y0 := yidx - 1
		while true do
		    x_input$mdeq(ExposeWindow + ExposeRegion + ExposeCopy, ev)
		    if ev.kind = ExposeCopy
		       then break end
		    display(w, lines, xidx, yidx, ev.x, ev.y, ev.x0, ev.y0,
			    forep, backp)
		    end
	 end
	end except when done: end
    x_window$destroy(w)
    end start_up

display = proc (w: x_window, lines: ab,
		xidx, yidx, x, y, width, height, forep, backp: int)
	    signals (done)
    own rast: _bytevec := _bytevec$create(2048)
    if width <= 0  cor  height <= 0
       then return end
    sx, sy, wd, ht, bw, ms, wk: int, iw: x_window := x_window$query(w)
    if ht <= 30  cor wd <= 30
       then signal done end
    xi: int := xidx + (x / 16) * 2
    if xi > 216
       then x_window$pix_set(w, backp, (217 - xidx) * 8, 0, wd, ht)
	    return
       end
    xj: int := xidx + (int$min(x + width, wd) / 16) * 2
    if xj > 216
       then x_window$pix_set(w, backp, (217 - xidx) * 8, 0, wd, ht)
	    xj := 216
       end
    x := (x / 16) * 16
    cnt: int := xj - xi + 1
    if cnt // 2 ~= 0
       then cnt := cnt + 1
	    xj := xj + 1
       end
    wd := cnt * 8
    ridx: int := 1
    j: int := 0
    yi: int := yidx + y
    yj: int := yidx + int$min(y + height, ht) - 1
    if yj > ab$size(lines)
       then x_window$pix_set(w, backp, x, ab$size(lines) - yidx + 1,
			     wd, ht)
	    yj := ab$size(lines)
       end
    ht := 2048 / cnt
    nobit: x_bitmap := x_bitmap$none()
    for i: int in int$from_to(yi, yj) do
	_bytevec$move_lr(lines[i], xi, rast, ridx, cnt)
	ridx := ridx + cnt
	if xj = 217
	   then rast[ridx - 1] := '\000' end
	j := j + 1
	if j < ht  cand  i < yj
	   then continue end
	x_window$bitmap_bitsput(w, wd, j, _cvt[_bytevec, _wordvec](rast),
				forep, backp, nobit,
				x, i - yidx - j + 1, GXcopy, -1)
	j := 0
	ridx := 1
	end
    end display

defax = proc (fs: string) returns (ab)
    bufsiz = 76 * 256
    states: as := as$[0: s0, s1, s2, s3]
    c: _chan := _chan$open(file_name$parse(fs), "read", 0)
    cbuf: _bytevec := _bytevec$create(bufsiz)
    cbidx: int := 1
    cbmax: int := 0
    b: _bytevec := _bytevec$create(76)
    lines: ab := ab$predict(1, 2300)
    line1: _bytevec := _bytevec$create(216)
    line2: _bytevec := _bytevec$create(216)
    block: int := 0
    xpos: int := 0
    while true do
	if cbidx > cbmax
	   then cbmax := _chan$getb(c, cbuf)
		cbidx := 1
	   end
	_bytevec$move_lr(cbuf, cbidx, b, 1, 76)
	cbidx := cbidx + 76
	if b[2] ~= '\071'
	   then continue end
	block := block + 1
	comp(b)
	max: int := getn(b, 47, 10)
	if max = 0
	   then continue end
	max := max + 77
	xpos := getn(b, 57, 12)
	if block = 2
	   then xpos := 1725 end
	n1: int := getn(b, 69, 3)
	n1pow: int := powers[n1]
	n1max: int := n1pow / 4
	n0: int := getn(b, 72, 3)
	n0pow: int := powers[n0]
	n0max: int := n0pow / 4
	s: state := states[getn(b, 75, 2)]
	tagcase s
	   tag _0, _3:
	       xpos := xpos + 1
	       if xpos = 1726
		  then xpos := 0 end
	   others:
	   end
	pos: int := 77
	while pos < max do
	    tagcase s
	       tag _0:
		   first: bool := true
		   xpos := xpos + 1
		   while pos < max do
		       i: int := getn(b, pos, n0)
		       xpos := xpos + i
		       pos := pos + n0
		       if i = n0pow
			  then first := false
			       if n0 < 7
				  then n0 := n0 + 1
				       n0pow := powers[n0]
				       n0max := n0pow / 4
				  end
			       continue
			  end
		       if first
			  then if n0 = 3  cand  i <= 3
				  then n0 := 2
				       n0pow := 3
				       n0max := 0
				elseif n0 > 3  cand i <= n0max
				  then n0 := n0 - 1
				       n0pow := n0pow / 2
				       n0max := n0pow / 4
				end
			  end
		       break
		       end
		   while xpos >= 1726 do
		       ab$addh(lines, line1)
		       ab$addh(lines, line2)
		       line1 := _bytevec$create(216)
		       line2 := _bytevec$create(216)
		       xpos := xpos - 1726
		       end
		   if pos >= max
		      then if pos > max
			      then error() end
			   break
		      end
		   if getb(b, pos)
		      then s := s4
		      else s := s3
		      end
	       tag _1:
		   k: int := 0
		   while pos < max do
		       k := k + 1
		       if ~getb(b, pos)
			  then pos := pos + 1
			       continue
			  end
		       break
		       end
		   while k > 0 do
		       i: int := int$min(int$min(k, 32), 1726 - xpos)
		       setn(line1, xpos, i)
		       xpos := xpos + i
		       k := k - i
		       if xpos = 1726
			  then ab$addh(lines, line1)
			       ab$addh(lines, line2)
			       line1 := _bytevec$create(216)
			       line2 := _bytevec$create(216)
			       xpos := 0
			  end
		       end
		   s := s5
	       tag _2:
		   k: int := 0
		   while pos < max do
		       k := k + 1
		       if getb(b, pos)
			  then pos := pos + 1
			       continue
			  end
		       break
		       end
		   while k > 0 do
		       i: int := int$min(int$min(k, 32), 1726 - xpos)
		       setn(line2, xpos, i)
		       xpos := xpos + i
		       k := k - i
		       if xpos = 1726
			  then ab$addh(lines, line1)
			       ab$addh(lines, line2)
			       line1 := _bytevec$create(216)
			       line2 := _bytevec$create(216)
			       xpos := 0
			  end
		       end
		   s := s8
	       tag _3:
		   first: bool := true
		   k: int := 1
		   while pos < max do
		       i: int := getn(b, pos, n1)
		       k := k + i
		       pos := pos + n1
		       if i = n1pow
			  then first := false
			       if n1 < 7
				  then n1 := n1 + 1
				       n1pow := powers[n1]
				       n1max := n1pow / 4
				  end
			       continue
			  end
		       if first
			  then if n1 = 3  cand  i <= 3
				  then n1 := 2
				       n1pow := 3
				       n1max := 0
				elseif n1 > 3  cand i <= n1max
				  then n1 := n1 - 1
				       n1pow := n1pow / 2
				       n1max := n1pow / 4
				end
			  end
		       break
		       end
		   while k > 0 do
		       i: int := int$min(int$min(k, 32), 1726 - xpos)
		       setn(line1, xpos, i)
		       setn(line2, xpos, i)
		       xpos := xpos + i
		       k := k - i
		       if xpos = 1726
			  then ab$addh(lines, line1)
			       ab$addh(lines, line2)
			       line1 := _bytevec$create(216)
			       line2 := _bytevec$create(216)
			       xpos := 0
			  end
		       end
		   if pos >= max
		      then if pos > max
			      then error() end
			   break
		      end
		   if getb(b, pos)
		      then s := s4
		      else s := s0
		      end
	       tag _4:
		   if getb(b, pos)
		      then s := s2
		      else s := s1
		      end
	       tag _5:
		   if getb(b, pos)
		      then s := s7
		      else s := s6
		      end
	       tag _6:
		   if getb(b, pos)
		      then s := s2
		      else s := s0
		      end
	       tag _7:
		   if getb(b, pos)
		      then s := s3
		      else error()
			   break
		      end
	       tag _8:
		   if getb(b, pos)
		      then s := s9
		      else s := s10
		      end
	       tag _9:
		   if getb(b, pos)
		      then s := s3
		      else s := s1
		      end
	       tag _10:
		   if getb(b, pos)
		      then error()
			   break
		      else s := s0
		      end
	       end
	    pos := pos + 1
	    end
	end except when end_of_file: end
    if xpos > 0
       then ab$addh(lines, line1)
	    ab$addh(lines, line2)
       end
    _chan$close(c)
    return(lines)
    end defax

error = proc ()
    _chan$puts(_chan$error_output(), "decoding error\r\n", false)
    end error

_cleanup_ = proc ()
    end _cleanup_