# This module contains code that has to do with text marks. These are used to
# implement  the  HTML  <A  NAME> tag, as well as the <A HREF="#name"> links.
# When we encounter a "<A NAME="foo">text</a> tag, we create a tk mark by the
# same  name  "foo",  with  $mark  used  to  count  the  marks in the current
# document.  We also create a link that starts at the  mark,  which  will  be
# given a distinct color to distinguish it from other links.

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #
# Create a new mark with a given name.

proc NewMark {w name} {
	global V me Ltag Link link Lnum mark
	if {$V>2} {set id "$me/NewMark $w $name"}
	incr mark
	set i [$w index insert]
	if {$V>3} {puts "$id: Mark $mark)=\"$name\" i=$i"}
	if {$V>3} {puts "$id: $w mark set $name $i"}
	set x [$w mark set $name $i]
	if {$V>3} {puts "$id: Got {$x}"}
	if {$V>3} {puts "$id: $w mark gravity $name left"}
	set x [$w mark gravity $name left]
	if {$V>3} {puts "$id: Got {$x}"}
	set Link([incr link]) $name
	if {$V>3} {puts "$id: Created Link($link)=\"$name\" for mark \"$name\""}
	$w tag bind Lnk$link <Enter> "LinkEnter $w $link %X %Y %W"
	$w tag bind Lnk$link <Leave> "LinkLeave $w $link %X %Y %W"
	set Lnum Lnk$link
	if {$V>3} {puts "$id: Change Ltag from $Ltag to Lname for Lnum=\"$Lnum\""}
	set Ltag Lname
}

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - #
# Go to a mark. That is, adjust the position in the window w so that the mark
# is visible.

proc ToMark {w mark} {
	global V me
	if {$V>2} {set id "$me/ToMark $w $name"}
	if {$V>3} {puts "$id: \"$mark\" is the target."}
	set i [$w index $mark]
	if {$V>3} {puts "$id: $w see $mark (index=$i)"}
	set x [$w see $mark]
	if {$V>3} {puts "$id: got \"$x\""}
	if {$V>3} {puts "$id: $w mark set insert $mark"}
	set x [$w mark set insert $mark]
	if {$V>3} {puts "$id: got \"$x\""}
}