Eskil

    # Add a dummy if it does not exists.
    proc addBalloon {args} {}
} else {
    namespace import -force psballoon::addBalloon
}

set debug 0
set diffver "Version 2.0.1+ 2004-03-30"
set thisScript [file join [pwd] [info script]]
set thisDir [file dirname $thisScript]

# Follow any link
set tmplink $thisScript
while {[file type $tmplink] eq "link"} {
    set tmplink [file readlink $tmplink]

# element is equal between the strings.
# This is sort of a Longest Common Subsequence algorithm but with
# a preference for long consecutive substrings, and it does not look
# for really small substrings.
##syntax compareMidString x x n n x?
proc compareMidString {s1 s2 res1Name res2Name {test 0}} {
    global Pref
    upvar $res1Name res1 $res2Name res2


    set len1 [string length $s1]
    set len2 [string length $s2]

    # Is s1 a substring of s2 ?
    if {$len1 < $len2} {
        set t [string first $s1 $s2]

    # Find the longest string common to both strings
    for {set t 0 ; set u $minlen} {$u < $len1} {incr t ; incr u} {
        set i [string first [string range $s1 $t $u] $s2]
        if {$i >= 0} {
            for {set p1 [expr {$u + 1}]; set p2 [expr {$i + $minlen + 1}]} \
                    {$p1 < $len1 && $p2 < $len2} {incr p1 ; incr p2} {
                if {[string index $s1 $p1] ne [string index $s2 $p2]} {
                    break
                }
            }
            if {$Pref(lineparsewords) != 0 && $test == 0} {
                set newt $t
                if {($t > 0 && [string index $s1 [expr {$t - 1}]] ne " ") || \
                    ($i > 0 && [string index $s2 [expr {$i - 1}]] ne " ")} {
                    for {} {$newt < $p1} {incr newt} {
                        if {[string index $s1 $newt] eq " "} break
                    }
                }

                set newp1 [expr {$p1 - 1}]
                if {($p1 < $len1 && [string index $s1 $p1] ne " ") || \
                    ($p2 < $len2 && [string index $s2 $p2] ne " ")} {
                    for {} {$newp1 > $newt} {incr newp1 -1} {
                        if {[string index $s1 $newp1] eq " "} break
                    }
                }
                incr newp1

                if {$newp1 - $newt > $minlen} {

        set mid1 [string range $s1 $found1 [expr {$found1 + $foundlen - 1}]]
        set right1 [string range $s1 [expr {$found1 + $foundlen}] end]

        set left2 [string range $s2 0 [expr {$found2 - 1}]]
        set mid2 [string range $s2 $found2 [expr {$found2 + $foundlen - 1}]]
        set right2 [string range $s2 [expr {$found2 + $foundlen}] end]

        compareMidString $left1 $left2 left1l left2l $test
        compareMidString $right1 $right2 right1l right2l $test

        set res1 [concat $left1l [list $mid1] $right1l]
        set res2 [concat $left2l [list $mid2] $right2l]
    }
}

# Experiment using DiffUtil
##syntax compareLinesX x x n n x?
proc compareLinesX {line1 line2 res1Name res2Name {test 0}} {
    global Pref

    upvar $res1Name res1
    upvar $res2Name res2

    # This processes the lines from both ends first.
    # A typical line has few changes thus this gets rid of most
    # equalities. The middle part is then optionally parsed further.

    if {$Pref(ignore) ne " "} {
        # Skip white space in both ends

        set apa1 [string trimleft $line1]
        set leftp1 [expr {[string length $line1] - [string length $apa1]}]
        set mid1 [string trimright $line1]

        set apa2 [string trimleft $line2]

    if {$leftp1 > $t1 && $leftp2 > $t2} {
        set res1 [list $line1]
        set res2 [list $line2]
    } else {
        set right1 [string range $line1 [expr {$t1 + 1}] end]
        set mid1 [string range $line1 $leftp1 $t1]
        set left1 [string range $line1 0 [expr {$leftp1 - 1}]]


        set right2 [string range $line2 [expr {$t2 + 1}] end]
        set mid2 [string range $line2 $leftp2 $t2]
        set left2 [string range $line2 0 [expr {$leftp2 - 1}]]


        if {$Pref(extralineparse) != 0 && $mid1 ne "" && $mid2 ne ""} {
            compareMidString $mid1 $mid2 mid1l mid2l $test

            # Replace middle element in res* with list elements from mid*
            set res1 [concat [list $left1] $mid1l [list $right1]]
            set res2 [concat [list $left2] $mid2l [list $right2]]
        } else {
            set res1 [list $left1 $mid1 $right1]
            set res2 [list $left2 $mid2 $right2]
        }
    }
}

# Compare two lines and rate how much they resemble each other.
# This has never worked well. Some day I'll sit down, think this through,
# and come up with a better algorithm.

    }
#    puts "Same ($sames)"
#    puts "D1   ($diffs1)"
#    puts "D2   ($diffs2)"
#    puts "S $sumsame D $sumdiff1 D $sumdiff2"
    return [expr {$sumsame - [maxAbs $sumdiff1 $sumdiff2]}]
}

# Initialise a multidimensional list with empty values
# This should use lrepeat once 8.5 is required
# The args are in the same order as indexes to lset/lindex
proc Linit {elem args} {
    for {set t [expr {[llength $args] - 1}]} {$t >= 0} {incr t -1} {
	set new {}
	for {set j [lindex $args $t]} {$j >= 1} {incr j -1} {
	    lappend new $elem
	}
	set elem $new
    }
    return $elem
}

# Decide how to display change blocks
# This tries to match the lines that resemble each other and put them
# next to each other.
# As the previous procedure, this would need a complete rework and a
# better algorithm.
proc compareBlocks {block1 block2} {

        set asym d
    } else {
        set dsym d
        set asym a
    }

    # Collect statistics
    set scores [Linit {} $size1 $size2]
    set emptyResult [Linit {} $size1]
    set scoresbest $emptyResult
    set origresult $emptyResult

    set j 0
    set bestsum 0
    foreach line1 $block1 {
        set bestscore -100000
        set bestline 0
        set i 0
        foreach line2 $block2 {
            set x [compareLines2 $line1 $line2]
            lset scores $j $i $x
#            puts "Score $j $i : $x"
            if {$x > $bestscore} {
                set bestscore $x
                set bestline $i
            }
            incr i
        }
#        puts "Best for $j is $bestline : $bestscore"
        lset origresult $j $bestline
        lset scoresbest $j $bestscore
        incr bestsum $bestscore
        incr j
    }
#    puts "Bestsum: $bestsum"

    # origresult holds a mapping between blocks where each row
    # is paired with its best match. This may not be a possible
    # result since it has to be in order.

    set bestresult $origresult
    set bestscoresum -100000

    # If the size is 1, it is automatically in order so we
    # don't need further processing.
    if {$size1 > 1} {

	# If both blocks are the same size, try first with the
	# simple row to row match, as a base score
	if {$size1 == $size2} {
	    set sum 0
	    set result $emptyResult
	    for {set i 0} {$i < $size1} {incr i} {
		lset result $i $i
		incr sum [lindex $scores $i $i]
	    }
#	    puts "Simple map sum: $sum"
	    set bestresult $result
	    set bestscoresum $sum
	}

	# If result is in order, no problem.
	# Otherwise, try to adjust result to make it ordered
        while {1} {
	    # The outer loop restarts from the "best mapping"
	    set result $origresult


            set mark [Linit 0 $size1]

            set high $mark

            while {1} {
		# The inner loop tries to get the result in order
                set besti 0
                set bestscore -100000
                set order 1
                for {set i 0} {$i < $size1} {incr i} {
                    if {[lindex $mark $i] == 0} {
                        for {set j [expr {$i + 1}]} {$j < $size1} {incr j} {
                            if {[lindex $mark $j] == 0} break
                        }
                        if {$j < $size1 && \
                                [lindex $result $i] >= [lindex $result $j]} {
                            set order 0
                        }
                        set x [lindex $scoresbest $i]
                        if {$x > $bestscore} {
                            set bestscore $x
                            set besti $i
                        }
                    }
                }
#                puts "Best $besti order $order sc $bestscore"
                if {$order} break
                lset mark $besti 1
                set bestr [lindex $result $besti]
                for {set i 0} {$i < $besti} {incr i} {
                    if {[lindex $mark $i] == 0 && \
                            [lindex $result $i] >= $bestr} {
                        lset mark $i 2
                    }
                }
                for {set i [expr {$besti + 1}]} {$i < $size1} {incr i} {
                    if {[lindex $mark $i] == 0 && \
                            [lindex $result $i] <= $bestr} {
                        lset mark $i 2
                    }
                }
            }

            set prev $size2
            for {set i [expr {$size1 - 1}]} {$i >= 0} {incr i -1} {
                if {[lindex $mark $i] != 2} {
                    set prev [lindex $result $i]
                } else {
                    lset high $i [expr {$prev - 1}]
                }
            }
            set prev -1
            for {set i 0} {$i < $size1} {incr i} {
                if {[lindex $mark $i] != 2} {
                    set prev [lindex $result $i]
                } else {
                    if {[lindex $high $i] > $prev} {
                        incr prev
                        lset result $i $prev
                    } else {
                        lset result $i -1
                    }
                }
            }
            set scoresum 0
            for {set i 0} {$i < $size1} {incr i} {
                set j [lindex $result $i]
                set sc [lindex $scores $i $j] ;# FIXA: can this fail?
                if {[string is integer -strict $sc]} {
#                    puts "Score: $i $j $scores($i,$j)"
                    incr scoresum $sc
                }
            }
#            puts "Scoresum: $scoresum ($bestscoresum)"

	    # If it was not an improvement over previous iteration, quit
            if {$scoresum <= $bestscoresum} {
                break
	    }

	    set bestresult $result
	    set bestscoresum $scoresum
	    # If it is close enough to the theoretical max, take it
	    if {$bestscoresum >= (3 * $bestsum / 4)} {
		break
	    }

	    # We are redoing from start, but try to improve by
	    # ignoring the most awkwardly placed line.
	    set mostp -1
	    set mosti 0
	    for {set i 0} {$i < $size1} {incr i} {
		if {[lindex $mark $i] == 1} {
		    if {abs([lindex $result $i] - $i) > $mostp} {
			set mostp [expr {abs([lindex $result $i] - $i)}]
                        set mosti $i
		    }
		}
	    }
#	    puts "Most $mosti $mostp"
	    lset scoresbest $mosti 0
        }
    }

    set result $bestresult

    # Collect the result into diff-like codes to use as display info.

    set apa {}
    set t1 0
    set t2 0
    while {$t1 < $size1 || $t2 < $size2} {
        if {$t1 < $size1} {
            set r [lindex $result $t1]
            if {$r < $t2 || $t2 >= $size2} {
                lappend apa $dsym
                incr t1
            } elseif {$r == $t2} {
                #if {[string match Wm* [lindex $block2 $t2]]} {
                #    puts "Left : [lindex $block1 $t1]"
                #    puts "Right: [lindex $block2 $t2]"
                #    puts "Score: $scores($t1,$t2)"
                #}

                # If the score is too bad, don't do line parsing.
                if {[lindex $scores $t1 $t2] < 0} {
                    lappend apa "C"
                } else {
                    lappend apa "c"
                }
                incr t1
                incr t2
            } else {

    close $ch

    if {$::tcl_platform(platform) eq "windows" &&\
            ![info exists ::env(ENSCRIPT_LIBRARY)]} {
        set ::env(ENSCRIPT_LIBRARY) [pwd]
    }
    set enscriptCmd [list enscript -2jcre -L 66 -M A4]
    if {![regexp {^(.*)( \(.*?\))$} $::diff($top,leftLabel) -> lfile lrest]} {
        set lfile $::diff($top,leftLabel)
        set lrest ""
    }
    set lfile [file tail $lfile]$lrest
    if {![regexp {^(.*)( \(.*?\))$} $::diff($top,rightLabel) -> rfile rrest]} {
        set rfile $::diff($top,rightLabel)