# This module contains assorted text-handling routines for JC's HTML viewer.

# We use a couple of arrays to keep track of white space and newlines:
#  wantNL($w) is number of newlines to be added to $w before the next text.
#  SP($w) is white space that is to be added to $w before the next text.
#  LC     is the last char that we added to any text widget.

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #
# Produce a "display" version of the string s.  This routine is used to build
# readable versions of strings with newlines converted to \n etc.

proc DSP s {
	global DSPtbl
	foreach c [array names DSPtbl] {
		set d $DSPtbl($c)
		regsub -all $c $s $d s
	}
	return $s
}
global DSPtbl
if [info exists DSPtbl] {unset DSPtbl}
array set DSPtbl {
	"\\\\" {\\}
	"\a" {\a} "\b" {\b} "\f" {\f} "\r" {\r} "\n" {\n} "\t" {\t} "\v" {\v}
	"\x01" {\x01} "\x02" {\x02} "\x03" {\x03} "\x07" {\x07} "\x11" {\x11} "\x13" {\x13}
}

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #
# Produce n newlines.  The first one is conditional, depending on whether the
# global  wantNL  variable says we just produced one.  If n > 1, we produce extra
# newlines, as needed by the <P> tag for instance.

proc Hnl {n} {
	global V me wantNL curD 
	if {$V>1} {set id "$me/Hnl"}
	if {$V>3} {puts "$id: $curD n=$n"}
	if ![info exists wantNL($curD)] {set wantNL($curD) 0}
	if {$V>3} {puts "$id: Change wantNL($curD) from $wantNL($curD) to $n."}
	set wantNL($curD) $n
	if {$V>3} {puts "$id: $curD n=$n wantNL($curD)=$wantNL($curD)"}
}

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #
proc tagHR {w a} {
	global C V me N in LC wantNL Src spat
	if {$V>1} {set id "$me/tagHR"}
	incr N(HR)
	if {$V>4} {puts "$id: HR $N(HR) attributes=\"$a\""}
	if {$V>4} {puts "$id: $w insert unmarked wantNL at end."} 
	$w insert end \n
	if {$V>4} {puts "$id: $w insert marked wantNL at end, before HR."} 
	$w insert end \n HR
	if [regexp -nocase {size=([0-9]+)} $a {} h] {
		set b [expr (1+$h)/2]
	} else {
		set h 5
		set b 3
	}
	if {$V>4} {puts "$id: Height is $h border is $b."} 
	if [winfo exists $w.hr$N(HR)] {
		$w.hr$N(HR) config -bd $b -relief raised
		if {$V>4} {puts "$id: $w.hr$N(HR) config -bd $b -relief raised"}
	} else {
		frame $w.hr$N(HR) -bd $b -relief raised
		if {$V>4} {puts "$id: frame $w.hr$N(HR) -bd $b -relief raised"}
	}
	if {$V>4} {puts "$id: $w window create insert -window \"$w.hr$N(HR)\""}
	$w window create insert -window $w.hr$N(HR)
	if {$V>4} {puts "$id: $w HR $N(HR) inserted."}
	if {$in(PRE) < 1} {
		if ![info exists wantNL($w)] {set wantNL($w) 0}
		if {$V>3} {puts "$id: Change wantNL($w) from $wantNL($w) to 0."}
		set wantNL($w) 0
	}
	if [regsub $spat $Src {} Src] {
		if {$V>3} {puts "$id: Stripped initial spaces from Src."}
	}
	if {$V>3} {puts "$me/HSP: Change SP($w) to {}."}
	HSP $w {}
	if {$V>4} {puts "$id: LC=\"$LC\" (end)"}
}

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #
# Hypertext spacing routine.  The arg s should be one or  more  white #
# chars of some sort.  We remember them, and the widget that they are #
# intended for, and the next call of Htxt will produce them.  This is #
# basically  a  kludge  to  minimize such spacing, and to suppress it #
# entirely at the end of a text widget.                               #
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #

proc HSP {w s} {
	global V me SP in
	if {$in(TITLE)} {set w TITLE}
	set SP($w) $s
	if {$V>3} {puts "$me/HSP: SP($w) is now \"[DSP $s]\""}
}

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #
# Put a chunk of HTMLized text out to a text widget.  If  the  global #
# curD  widget  is  defined, we use it as the target instead, so that #
# the caller can redirect all of the output of subprocesses.  We look #
# for titles, and copy the text to our title bar.                     #
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #
proc Htxt t {
	global V me curD LC Lnum Ltag Ftag in Mtab wantNL title TxtLen TxtMinw TxtMaxw
	set id "$me/Htxt"
	if {$in(TITLE)} {set w TITLE} else {set w $curD}
	if {$V>4} {puts "$id: $w t=\"$t\""}
	DoSP
	if {$in(TITLE)} {
		if {$V>1} {puts "$id: TITLE title=\"$title\" t=\"$t\""}
		append title $t
		if {$V>1} {puts "$id: title=\"$title\""}
		wm title . $title
	}
	if {$V>2} {puts "$id: $w contains $TxtLen($w) chars."}
	if {$t != {}} {
		if {$w != {TITLE}} {
			if {$V>4} {puts "$id: $w insert end \"$t\" \"$Mtab F$Ftag $Ltag $Lnum\""}
			$w insert end $t "$Mtab F$Ftag $Ltag $Lnum"
			$w tag raise $Lnum
		}
		incr TxtLen($w) [string length $t]
		if {$V>2} {puts "$id: $w TxtLen=$TxtLen($w) chars."}
		set pxls [font measure [FontName $w] $t]
		if {$V>1} {puts "$id: Add $pxls pixels for \"$t\""}
		if ![info exists TxtMinw($w)] {set TxtMinw($w) 0}
		if ![info exists TxtMaxw($w)] {set TxtMaxw($w) 0}
		incr TxtMaxw($w) $pxls
		if {$V>1} {puts "$id: $w now contains $TxtLen($w) chars \[$TxtMinw($w),$TxtMaxw($w)\] pixels."}
		set LC [string range $t end end]
	}
	if {$V>2} {puts "$id: $w now contains TxtLen=$TxtLen($w) chars LC={$LC} wantNL($curD)=$wantNL($curD)"}
}

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #
# Here's the routine that puts out spaces. This gets a bit tricky. #
#
proc DoSP {} {
	global V me LC wantNL PicMinw SP curD TxtLen in title TxtMinw TxtMaxw
	set id "$me/DoSP"
	if {$in(TITLE)} {set w TITLE} else {set w $curD}
	if ![info exists      SP($w)] {set      SP($w) {}}
	if ![info exists  TxtLen($w)] {set  TxtLen($w) 0}
	if ![info exists PicMinw($w)] {set PicMinw($w) 0}
	if {$V>4} {puts "$id: $w SP=\"$SP($w)\" wantNL=$wantNL($w) TxtLen=$TxtLen($w) PicMinw=$PicMinw($w)."}
	if {$TxtLen($w) < 1 && $PicMinw($w) < 1} {
		if {$V>4} {
			if {$TxtLen($w)<1} {puts "$id: $w suppressing initial white space because TxtLen($w)=$TxtLen($w)."}
			if {$PicMinw($w)<1} {puts "$id: $w suppressing initial white space because PicMinw($w)=$PicMinw($w)."}
		}
		if {$V>3} {puts "$id: Change SP($w) from \"[DSP $SP($w)]\" to {}."}
		HSP $w {}
		if ![info exists wantNL($w)] {set wantNL($w) 0}
		if {$V>3} {puts "$id: Change wantNL($w) from $wantNL($w) to 0."}
		set wantNL($w) 0
	}
	while {$wantNL($w) > 0} {
		if {!$in(TITLE)} {
			if {$V>4} {puts "$id: $w insert end newline $wantNL($w)."}
			$w insert end [set LC "\n"]
		}
		incr wantNL($w) -1
		if {$V>3} {puts "$id: Change SP($w) from \"[DSP $SP($w)]\" to \"\"."}
		HSP $w {}
	}
	if {$V>4} {puts "$id: $w SP=\"$SP($w)\"."}
	if {$SP($w) != {}} {
		if {$V>4} {puts "$id: $w needs a space \"$SP($w)\"."}
		if {$in(TITLE)} {
			append title { }
		} else {
			set s $SP($w)
			if {$V>4} {puts "$id: $w insert end \"$s\""}
			$w insert end $s
			set pxls [font measure [FontName $w] $s]
			if {$V>1} {puts "$id: Add $pxls pixels for \"$s\""}
			incr TxtMaxw($w) $pxls
			if {$V>1} {puts "$id: $w now contains $TxtLen($w) chars \[$TxtMinw($w),$TxtMaxw($w)\] pixels."}
		}
		if {$V>3} {puts "$id: Change SP($w) from \"[DSP $SP($w)]\" to {}."}
		HSP $w {}
		if ![info exists wantNL($w)] {set wantNL($w) 0}
		if {$V>3} {puts "$id: Change wantNL($w) from $wantNL($w) to 0."}
		set wantNL($w) 0
	}
}