#!/bin/sh
# Tcl ignores the next line -*- tcl -*- \
exec wish "$0" -- "$@"

# Copyright (C) 2005 Paul Mackerras.  All rights reserved.
# This program is free software; it may be used, copied, modified
# and distributed under the terms of the GNU General Public Licence,
# either version 2, or (at your option) any later version.

proc gitdir {} {
    global env
    if {[info exists env(GIT_DIR)]} {
	return $env(GIT_DIR)
    } else {
	return ".git"
    }
}

proc getcommits {rargs} {
    global commits commfd phase canv mainfont env
    global startmsecs nextupdate ncmupdate
    global ctext maincursor textcursor leftover

    # check that we can find a .git directory somewhere...
    set gitdir [gitdir]
    if {![file isdirectory $gitdir]} {
	error_popup "Cannot find the git directory \"$gitdir\"."
	exit 1
    }
    set commits {}
    set phase getcommits
    set startmsecs [clock clicks -milliseconds]
    set nextupdate [expr $startmsecs + 100]
    set ncmupdate 1
    if [catch {
	set parse_args [concat --default HEAD $rargs]
	set parsed_args [split [eval exec git-rev-parse $parse_args] "\n"]
    }] {
	# if git-rev-parse failed for some reason...
	if {$rargs == {}} {
	    set rargs HEAD
	}
	set parsed_args $rargs
    }
    if [catch {
	set commfd [open "|git-rev-list --header --topo-order --parents $parsed_args" r]
    } err] {
	puts stderr "Error executing git-rev-list: $err"
	exit 1
    }
    set leftover {}
    fconfigure $commfd -blocking 0 -translation lf
    fileevent $commfd readable [list getcommitlines $commfd]
    $canv delete all
    $canv create text 3 3 -anchor nw -text "Reading commits..." \
	-font $mainfont -tags textitems
    . config -cursor watch
    settextcursor watch
}

proc getcommitlines {commfd}  {
    global commits parents cdate children
    global commitlisted phase commitinfo nextupdate
    global stopped redisplaying leftover

    set stuff [read $commfd]
    if {$stuff == {}} {
	if {![eof $commfd]} return
	# set it blocking so we wait for the process to terminate
	fconfigure $commfd -blocking 1
	if {![catch {close $commfd} err]} {
	    after idle finishcommits
	    return
	}
	if {[string range $err 0 4] == "usage"} {
	    set err \
{Gitk: error reading commits: bad arguments to git-rev-list.
(Note: arguments to gitk are passed to git-rev-list
to allow selection of commits to be displayed.)}
	} else {
	    set err "Error reading commits: $err"
	}
	error_popup $err
	exit 1
    }
    set start 0
    while 1 {
	set i [string first "\0" $stuff $start]
	if {$i < 0} {
	    append leftover [string range $stuff $start end]
	    return
	}
	set cmit [string range $stuff $start [expr {$i - 1}]]
	if {$start == 0} {
	    set cmit "$leftover$cmit"
	    set leftover {}
	}
	set start [expr {$i + 1}]
	set j [string first "\n" $cmit]
	set ok 0
	if {$j >= 0} {
	    set ids [string range $cmit 0 [expr {$j - 1}]]
	    set ok 1
	    foreach id $ids {
		if {![regexp {^[0-9a-f]{40}$} $id]} {
		    set ok 0
		    break
		}
	    }
	}
	if {!$ok} {
	    set shortcmit $cmit
	    if {[string length $shortcmit] > 80} {
		set shortcmit "[string range $shortcmit 0 80]..."
	    }
	    error_popup "Can't parse git-rev-list output: {$shortcmit}"
	    exit 1
	}
	set id [lindex $ids 0]
	set olds [lrange $ids 1 end]
	set cmit [string range $cmit [expr {$j + 1}] end]
	lappend commits $id
	set commitlisted($id) 1
	parsecommit $id $cmit 1 [lrange $ids 1 end]
	drawcommit $id
	if {[clock clicks -milliseconds] >= $nextupdate} {
	    doupdate 1
	}
	while {$redisplaying} {
	    set redisplaying 0
	    if {$stopped == 1} {
		set stopped 0
		set phase "getcommits"
		foreach id $commits {
		    drawcommit $id
		    if {$stopped} break
		    if {[clock clicks -milliseconds] >= $nextupdate} {
			doupdate 1
		    }
		}
	    }
	}
    }
}

proc doupdate {reading} {
    global commfd nextupdate numcommits ncmupdate

    if {$reading} {
	fileevent $commfd readable {}
    }
    update
    set nextupdate [expr {[clock clicks -milliseconds] + 100}]
    if {$numcommits < 100} {
	set ncmupdate [expr {$numcommits + 1}]
    } elseif {$numcommits < 10000} {
	set ncmupdate [expr {$numcommits + 10}]
    } else {
	set ncmupdate [expr {$numcommits + 100}]
    }
    if {$reading} {
	fileevent $commfd readable [list getcommitlines $commfd]
    }
}

proc readcommit {id} {
    if [catch {set contents [exec git-cat-file commit $id]}] return
    parsecommit $id $contents 0 {}
}

proc parsecommit {id contents listed olds} {
    global commitinfo children nchildren parents nparents cdate ncleft

    set inhdr 1
    set comment {}
    set headline {}
    set auname {}
    set audate {}
    set comname {}
    set comdate {}
    if {![info exists nchildren($id)]} {
	set children($id) {}
	set nchildren($id) 0
	set ncleft($id) 0
    }
    set parents($id) $olds
    set nparents($id) [llength $olds]
    foreach p $olds {
	if {![info exists nchildren($p)]} {
	    set children($p) [list $id]
	    set nchildren($p) 1
	    set ncleft($p) 1
	} elseif {[lsearch -exact $children($p) $id] < 0} {
	    lappend children($p) $id
	    incr nchildren($p)
	    incr ncleft($p)
	}
    }
    foreach line [split $contents "\n"] {
	if {$inhdr} {
	    if {$line == {}} {
		set inhdr 0
	    } else {
		set tag [lindex $line 0]
		if {$tag == "author"} {
		    set x [expr {[llength $line] - 2}]
		    set audate [lindex $line $x]
		    set auname [lrange $line 1 [expr {$x - 1}]]
		} elseif {$tag == "committer"} {
		    set x [expr {[llength $line] - 2}]
		    set comdate [lindex $line $x]
		    set comname [lrange $line 1 [expr {$x - 1}]]
		}
	    }
	} else {
	    if {$comment == {}} {
		set headline [string trim $line]
	    } else {
		append comment "\n"
	    }
	    if {!$listed} {
		# git-rev-list indents the comment by 4 spaces;
		# if we got this via git-cat-file, add the indentation
		append comment "    "
	    }
	    append comment $line
	}
    }
    if {$audate != {}} {
	set audate [clock format $audate -format "%Y-%m-%d %H:%M:%S"]
    }
    if {$comdate != {}} {
	set cdate($id) $comdate
	set comdate [clock format $comdate -format "%Y-%m-%d %H:%M:%S"]
    }
    set commitinfo($id) [list $headline $auname $audate \
			     $comname $comdate $comment]
}

proc readrefs {} {
    global tagids idtags headids idheads tagcontents

    set tags [glob -nocomplain -types f [gitdir]/refs/tags/*]
    foreach f $tags {
	catch {
	    set fd [open $f r]
	    set line [read $fd]
	    if {[regexp {^[0-9a-f]{40}} $line id]} {
		set direct [file tail $f]
		set tagids($direct) $id
		lappend idtags($id) $direct
		set tagblob [exec git-cat-file tag $id]
		set contents [split $tagblob "\n"]
		set obj {}
		set type {}
		set tag {}
		foreach l $contents {
		    if {$l == {}} break
		    switch -- [lindex $l 0] {
			"object" {set obj [lindex $l 1]}
			"type" {set type [lindex $l 1]}
			"tag" {set tag [string range $l 4 end]}
		    }
		}
		if {$obj != {} && $type == "commit" && $tag != {}} {
		    set tagids($tag) $obj
		    lappend idtags($obj) $tag
		    set tagcontents($tag) $tagblob
		}
	    }
	    close $fd
	}
    }
    set heads [glob -nocomplain -types f [gitdir]/refs/heads/*]
    foreach f $heads {
	catch {
	    set fd [open $f r]
	    set line [read $fd 40]
	    if {[regexp {^[0-9a-f]{40}} $line id]} {
		set head [file tail $f]
		set headids($head) $line
		lappend idheads($line) $head
	    }
	    close $fd
	}
    }
    readotherrefs refs {} {tags heads}
}

proc readotherrefs {base dname excl} {
    global otherrefids idotherrefs

    set git [gitdir]
    set files [glob -nocomplain -types f [file join $git $base *]]
    foreach f $files {
	catch {
	    set fd [open $f r]
	    set line [read $fd 40]
	    if {[regexp {^[0-9a-f]{40}} $line id]} {
		set name "$dname[file tail $f]"
		set otherrefids($name) $id
		lappend idotherrefs($id) $name
	    }
	    close $fd
	}
    }
    set dirs [glob -nocomplain -types d [file join $git $base *]]
    foreach d $dirs {
	set dir [file tail $d]
	if {[lsearch -exact $excl $dir] >= 0} continue
	readotherrefs [file join $base $dir] "$dname$dir/" {}
    }
}

proc error_popup msg {
    set w .error
    toplevel $w
    wm transient $w .
    message $w.m -text $msg -justify center -aspect 400
    pack $w.m -side top -fill x -padx 20 -pady 20
    button $w.ok -text OK -command "destroy $w"
    pack $w.ok -side bottom -fill x
    bind $w <Visibility> "grab $w; focus $w"
    tkwait window $w
}

proc makewindow {} {
    global canv canv2 canv3 linespc charspc ctext cflist textfont
    global findtype findtypemenu findloc findstring fstring geometry
    global entries sha1entry sha1string sha1but
    global maincursor textcursor curtextcursor
    global rowctxmenu gaudydiff mergemax

    menu .bar
    .bar add cascade -label "File" -menu .bar.file
    menu .bar.file
    .bar.file add command -label "Reread references" -command rereadrefs
    .bar.file add command -label "Quit" -command doquit
    menu .bar.help
    .bar add cascade -label "Help" -menu .bar.help
    .bar.help add command -label "About gitk" -command about
    . configure -menu .bar

    if {![info exists geometry(canv1)]} {
	set geometry(canv1) [expr 45 * $charspc]
	set geometry(canv2) [expr 30 * $charspc]
	set geometry(canv3) [expr 15 * $charspc]
	set geometry(canvh) [expr 25 * $linespc + 4]
	set geometry(ctextw) 80
	set geometry(ctexth) 30
	set geometry(cflistw) 30
    }
    panedwindow .ctop -orient vertical
    if {[info exists geometry(width)]} {
	.ctop conf -width $geometry(width) -height $geometry(height)
	set texth [expr {$geometry(height) - $geometry(canvh) - 56}]
	set geometry(ctexth) [expr {($texth - 8) /
				    [font metrics $textfont -linespace]}]
    }
    frame .ctop.top
    frame .ctop.top.bar
    pack .ctop.top.bar -side bottom -fill x
    set cscroll .ctop.top.csb
    scrollbar $cscroll -command {allcanvs yview} -highlightthickness 0
    pack $cscroll -side right -fill y
    panedwindow .ctop.top.clist -orient horizontal -sashpad 0 -handlesize 4
    pack .ctop.top.clist -side top -fill both -expand 1
    .ctop add .ctop.top
    set canv .ctop.top.clist.canv
    canvas $canv -height $geometry(canvh) -width $geometry(canv1) \
	-bg white -bd 0 \
	-yscrollincr $linespc -yscrollcommand "$cscroll set"
    .ctop.top.clist add $canv
    set canv2 .ctop.top.clist.canv2
    canvas $canv2 -height $geometry(canvh) -width $geometry(canv2) \
	-bg white -bd 0 -yscrollincr $linespc
    .ctop.top.clist add $canv2
    set canv3 .ctop.top.clist.canv3
    canvas $canv3 -height $geometry(canvh) -width $geometry(canv3) \
	-bg white -bd 0 -yscrollincr $linespc
    .ctop.top.clist add $canv3
    bind .ctop.top.clist <Configure> {resizeclistpanes %W %w}

    set sha1entry .ctop.top.bar.sha1
    set entries $sha1entry
    set sha1but .ctop.top.bar.sha1label
    button $sha1but -text "SHA1 ID: " -state disabled -relief flat \
	-command gotocommit -width 8
    $sha1but conf -disabledforeground [$sha1but cget -foreground]
    pack .ctop.top.bar.sha1label -side left
    entry $sha1entry -width 40 -font $textfont -textvariable sha1string
    trace add variable sha1string write sha1change
    pack $sha1entry -side left -pady 2

    image create bitmap bm-left -data {
	#define left_width 16
	#define left_height 16
	static unsigned char left_bits[] = {
	0x00, 0x00, 0xc0, 0x01, 0xe0, 0x00, 0x70, 0x00, 0x38, 0x00, 0x1c, 0x00,
	0x0e, 0x00, 0xff, 0x7f, 0xff, 0x7f, 0xff, 0x7f, 0x0e, 0x00, 0x1c, 0x00,
	0x38, 0x00, 0x70, 0x00, 0xe0, 0x00, 0xc0, 0x01};
    }
    image create bitmap bm-right -data {
	#define right_width 16
	#define right_height 16
	static unsigned char right_bits[] = {
	0x00, 0x00, 0xc0, 0x01, 0x80, 0x03, 0x00, 0x07, 0x00, 0x0e, 0x00, 0x1c,
	0x00, 0x38, 0xff, 0x7f, 0xff, 0x7f, 0xff, 0x7f, 0x00, 0x38, 0x00, 0x1c,
	0x00, 0x0e, 0x00, 0x07, 0x80, 0x03, 0xc0, 0x01};
    }
    button .ctop.top.bar.leftbut -image bm-left -command goback \
	-state disabled -width 26
    pack .ctop.top.bar.leftbut -side left -fill y
    button .ctop.top.bar.rightbut -image bm-right -command goforw \
	-state disabled -width 26
    pack .ctop.top.bar.rightbut -side left -fill y

    button .ctop.top.bar.findbut -text "Find" -command dofind
    pack .ctop.top.bar.findbut -side left
    set findstring {}
    set fstring .ctop.top.bar.findstring
    lappend entries $fstring
    entry $fstring -width 30 -font $textfont -textvariable findstring
    pack $fstring -side left -expand 1 -fill x
    set findtype Exact
    set findtypemenu [tk_optionMenu .ctop.top.bar.findtype \
			  findtype Exact IgnCase Regexp]
    set findloc "All fields"
    tk_optionMenu .ctop.top.bar.findloc findloc "All fields" Headline \
	Comments Author Committer Files Pickaxe
    pack .ctop.top.bar.findloc -side right
    pack .ctop.top.bar.findtype -side right
    # for making sure type==Exact whenever loc==Pickaxe
    trace add variable findloc write findlocchange

    panedwindow .ctop.cdet -orient horizontal
    .ctop add .ctop.cdet
    frame .ctop.cdet.left
    set ctext .ctop.cdet.left.ctext
    text $ctext -bg white -state disabled -font $textfont \
	-width $geometry(ctextw) -height $geometry(ctexth) \
	-yscrollcommand ".ctop.cdet.left.sb set" -wrap none
    scrollbar .ctop.cdet.left.sb -command "$ctext yview"
    pack .ctop.cdet.left.sb -side right -fill y
    pack $ctext -side left -fill both -expand 1
    .ctop.cdet add .ctop.cdet.left

    $ctext tag conf filesep -font [concat $textfont bold] -back "#aaaaaa"
    if {$gaudydiff} {
	$ctext tag conf hunksep -back blue -fore white
	$ctext tag conf d0 -back "#ff8080"
	$ctext tag conf d1 -back green
    } else {
	$ctext tag conf hunksep -fore blue
	$ctext tag conf d0 -fore red
	$ctext tag conf d1 -fore "#00a000"
	$ctext tag conf m0 -fore red
	$ctext tag conf m1 -fore blue
	$ctext tag conf m2 -fore green
	$ctext tag conf m3 -fore purple
	$ctext tag conf m4 -fore brown
	$ctext tag conf mmax -fore darkgrey
	set mergemax 5
	$ctext tag conf mresult -font [concat $textfont bold]
	$ctext tag conf msep -font [concat $textfont bold]
	$ctext tag conf found -back yellow
    }

    frame .ctop.cdet.right
    set cflist .ctop.cdet.right.cfiles
    listbox $cflist -bg white -selectmode extended -width $geometry(cflistw) \
	-yscrollcommand ".ctop.cdet.right.sb set"
    scrollbar .ctop.cdet.right.sb -command "$cflist yview"
    pack .ctop.cdet.right.sb -side right -fill y
    pack $cflist -side left -fill both -expand 1
    .ctop.cdet add .ctop.cdet.right
    bind .ctop.cdet <Configure> {resizecdetpanes %W %w}

    pack .ctop -side top -fill both -expand 1

    bindall <1> {selcanvline %W %x %y}
    #bindall <B1-Motion> {selcanvline %W %x %y}
    bindall <ButtonRelease-4> "allcanvs yview scroll -5 units"
    bindall <ButtonRelease-5> "allcanvs yview scroll 5 units"
    bindall <2> "allcanvs scan mark 0 %y"
    bindall <B2-Motion> "allcanvs scan dragto 0 %y"
    bind . <Key-Up> "selnextline -1"
    bind . <Key-Down> "selnextline 1"
    bind . <Key-Right> "goforw"
    bind . <Key-Left> "goback"
    bind . <Key-Prior> "allcanvs yview scroll -1 pages"
    bind . <Key-Next> "allcanvs yview scroll 1 pages"
    bindkey <Key-Delete> "$ctext yview scroll -1 pages"
    bindkey <Key-BackSpace> "$ctext yview scroll -1 pages"
    bindkey <Key-space> "$ctext yview scroll 1 pages"
    bindkey p "selnextline -1"
    bindkey n "selnextline 1"
    bindkey z "goback"
    bindkey x "goforw"
    bindkey i "selnextline -1"
    bindkey k "selnextline 1"
    bindkey j "goback"
    bindkey l "goforw"
    bindkey b "$ctext yview scroll -1 pages"
    bindkey d "$ctext yview scroll 18 units"
    bindkey u "$ctext yview scroll -18 units"
    bindkey / {findnext 1}
    bindkey <Key-Return> {findnext 0}
    bindkey ? findprev
    bindkey f nextfile
    bind . <Control-q> doquit
    bind . <Control-f> dofind
    bind . <Control-g> {findnext 0}
    bind . <Control-r> findprev
    bind . <Control-equal> {incrfont 1}
    bind . <Control-KP_Add> {incrfont 1}
    bind . <Control-minus> {incrfont -1}
    bind . <Control-KP_Subtract> {incrfont -1}
    bind $cflist <<ListboxSelect>> listboxsel
    bind . <Destroy> {savestuff %W}
    bind . <Button-1> "click %W"
    bind $fstring <Key-Return> dofind
    bind $sha1entry <Key-Return> gotocommit
    bind $sha1entry <<PasteSelection>> clearsha1

    set maincursor [. cget -cursor]
    set textcursor [$ctext cget -cursor]
    set curtextcursor $textcursor

    set rowctxmenu .rowctxmenu
    menu $rowctxmenu -tearoff 0
    $rowctxmenu add command -label "Diff this -> selected" \
	-command {diffvssel 0}
    $rowctxmenu add command -label "Diff selected -> this" \
	-command {diffvssel 1}
    $rowctxmenu add command -label "Make patch" -command mkpatch
    $rowctxmenu add command -label "Create tag" -command mktag
    $rowctxmenu add command -label "Write commit to file" -command writecommit
}

# when we make a key binding for the toplevel, make sure
# it doesn't get triggered when that key is pressed in the
# find string entry widget.
proc bindkey {ev script} {
    global entries
    bind . $ev $script
    set escript [bind Entry $ev]
    if {$escript == {}} {
	set escript [bind Entry <Key>]
    }
    foreach e $entries {
	bind $e $ev "$escript; break"
    }
}

# set the focus back to the toplevel for any click outside
# the entry widgets
proc click {w} {
    global entries
    foreach e $entries {
	if {$w == $e} return
    }
    focus .
}

proc savestuff {w} {
    global canv canv2 canv3 ctext cflist mainfont textfont
    global stuffsaved findmergefiles gaudydiff maxgraphpct
    global maxwidth

    if {$stuffsaved} return
    if {![winfo viewable .]} return
    catch {
	set f [open "~/.gitk-new" w]
	puts $f [list set mainfont $mainfont]
	puts $f [list set textfont $textfont]
	puts $f [list set findmergefiles $findmergefiles]
	puts $f [list set gaudydiff $gaudydiff]
	puts $f [list set maxgraphpct $maxgraphpct]
	puts $f [list set maxwidth $maxwidth]
	puts $f "set geometry(width) [winfo width .ctop]"
	puts $f "set geometry(height) [winfo height .ctop]"
	puts $f "set geometry(canv1) [expr [winfo width $canv]-2]"
	puts $f "set geometry(canv2) [expr [winfo width $canv2]-2]"
	puts $f "set geometry(canv3) [expr [winfo width $canv3]-2]"
	puts $f "set geometry(canvh) [expr [winfo height $canv]-2]"
	set wid [expr {([winfo width $ctext] - 8) \
			   / [font measure $textfont "0"]}]
	puts $f "set geometry(ctextw) $wid"
	set wid [expr {([winfo width $cflist] - 11) \
			   / [font measure [$cflist cget -font] "0"]}]
	puts $f "set geometry(cflistw) $wid"
	close $f
	file rename -force "~/.gitk-new" "~/.gitk"
    }
    set stuffsaved 1
}

proc resizeclistpanes {win w} {
    global oldwidth
    if [info exists oldwidth($win)] {
	set s0 [$win sash coord 0]
	set s1 [$win sash coord 1]
	if {$w < 60} {
	    set sash0 [expr {int($w/2 - 2)}]
	    set sash1 [expr {int($w*5/6 - 2)}]
	} else {
	    set factor [expr {1.0 * $w / $oldwidth($win)}]
	    set sash0 [expr {int($factor * [lindex $s0 0])}]
	    set sash1 [expr {int($factor * [lindex $s1 0])}]
	    if {$sash0 < 30} {
		set sash0 30
	    }
	    if {$sash1 < $sash0 + 20} {
		set sash1 [expr $sash0 + 20]
	    }
	    if {$sash1 > $w - 10} {
		set sash1 [expr $w - 10]
		if {$sash0 > $sash1 - 20} {
		    set sash0 [expr $sash1 - 20]
		}
	    }
	}
	$win sash place 0 $sash0 [lindex $s0 1]
	$win sash place 1 $sash1 [lindex $s1 1]
    }
    set oldwidth($win) $w
}

proc resizecdetpanes {win w} {
    global oldwidth
    if [info exists oldwidth($win)] {
	set s0 [$win sash coord 0]
	if {$w < 60} {
	    set sash0 [expr {int($w*3/4 - 2)}]
	} else {
	    set factor [expr {1.0 * $w / $oldwidth($win)}]
	    set sash0 [expr {int($factor * [lindex $s0 0])}]
	    if {$sash0 < 45} {
		set sash0 45
	    }
	    if {$sash0 > $w - 15} {
		set sash0 [expr $w - 15]
	    }
	}
	$win sash place 0 $sash0 [lindex $s0 1]
    }
    set oldwidth($win) $w
}

proc allcanvs args {
    global canv canv2 canv3
    eval $canv $args
    eval $canv2 $args
    eval $canv3 $args
}

proc bindall {event action} {
    global canv canv2 canv3
    bind $canv $event $action
    bind $canv2 $event $action
    bind $canv3 $event $action
}

proc about {} {
    set w .about
    if {[winfo exists $w]} {
	raise $w
	return
    }
    toplevel $w
    wm title $w "About gitk"
    message $w.m -text {
Gitk version 1.2

Copyright © 2005 Paul Mackerras

Use and redistribute under the terms of the GNU General Public License} \
	    -justify center -aspect 400
    pack $w.m -side top -fill x -padx 20 -pady 20
    button $w.ok -text Close -command "destroy $w"
    pack $w.ok -side bottom
}

proc assigncolor {id} {
    global commitinfo colormap commcolors colors nextcolor
    global parents nparents children nchildren
    global cornercrossings crossings

    if [info exists colormap($id)] return
    set ncolors [llength $colors]
    if {$nparents($id) <= 1 && $nchildren($id) == 1} {
	set child [lindex $children($id) 0]
	if {[info exists colormap($child)]
	    && $nparents($child) == 1} {
	    set colormap($id) $colormap($child)
	    return
	}
    }
    set badcolors {}
    if {[info exists cornercrossings($id)]} {
	foreach x $cornercrossings($id) {
	    if {[info exists colormap($x)]
		&& [lsearch -exact $badcolors $colormap($x)] < 0} {
		lappend badcolors $colormap($x)
	    }
	}
	if {[llength $badcolors] >= $ncolors} {
	    set badcolors {}
	}
    }
    set origbad $badcolors
    if {[llength $badcolors] < $ncolors - 1} {
	if {[info exists crossings($id)]} {
	    foreach x $crossings($id) {
		if {[info exists colormap($x)]
		    && [lsearch -exact $badcolors $colormap($x)] < 0} {
		    lappend badcolors $colormap($x)
		}
	    }
	    if {[llength $badcolors] >= $ncolors} {
		set badcolors $origbad
	    }
	}
	set origbad $badcolors
    }
    if {[llength $badcolors] < $ncolors - 1} {
	foreach child $children($id) {
	    if {[info exists colormap($child)]
		&& [lsearch -exact $badcolors $colormap($child)] < 0} {
		lappend badcolors $colormap($child)
	    }
	    if {[info exists parents($child)]} {
		foreach p $parents($child) {
		    if {[info exists colormap($p)]
			&& [lsearch -exact $badcolors $colormap($p)] < 0} {
			lappend badcolors $colormap($p)
		    }
		}
	    }
	}
	if {[llength $badcolors] >= $ncolors} {
	    set badcolors $origbad
	}
    }
    for {set i 0} {$i <= $ncolors} {incr i} {
	set c [lindex $colors $nextcolor]
	if {[incr nextcolor] >= $ncolors} {
	    set nextcolor 0
	}
	if {[lsearch -exact $badcolors $c]} break
    }
    set colormap($id) $c
}

proc initgraph {} {
    global canvy canvy0 lineno numcommits nextcolor linespc
    global mainline mainlinearrow sidelines
    global nchildren ncleft
    global displist nhyperspace

    allcanvs delete all
    set nextcolor 0
    set canvy $canvy0
    set lineno -1
    set numcommits 0
    catch {unset mainline}
    catch {unset mainlinearrow}
    catch {unset sidelines}
    foreach id [array names nchildren] {
	set ncleft($id) $nchildren($id)
    }
    set displist {}
    set nhyperspace 0
}

proc bindline {t id} {
    global canv

    $canv bind $t <Enter> "lineenter %x %y $id"
    $canv bind $t <Motion> "linemotion %x %y $id"
    $canv bind $t <Leave> "lineleave $id"
    $canv bind $t <Button-1> "lineclick %x %y $id 1"
}

proc drawlines {id xtra} {
    global mainline mainlinearrow sidelines lthickness colormap canv

    $canv delete lines.$id
    if {[info exists mainline($id)]} {
	set t [$canv create line $mainline($id) \
		   -width [expr {($xtra + 1) * $lthickness}] \
		   -fill $colormap($id) -tags lines.$id \
		   -arrow $mainlinearrow($id)]
	$canv lower $t
	bindline $t $id
    }
    if {[info exists sidelines($id)]} {
	foreach ls $sidelines($id) {
	    set coords [lindex $ls 0]
	    set thick [lindex $ls 1]
	    set arrow [lindex $ls 2]
	    set t [$canv create line $coords -fill $colormap($id) \
		       -width [expr {($thick + $xtra) * $lthickness}] \
		       -arrow $arrow -tags lines.$id]
	    $canv lower $t
	    bindline $t $id
	}
    }
}

# level here is an index in displist
proc drawcommitline {level} {
    global parents children nparents displist
    global canv canv2 canv3 mainfont namefont canvy linespc
    global lineid linehtag linentag linedtag commitinfo
    global colormap numcommits currentparents dupparents
    global idtags idline idheads idotherrefs
    global lineno lthickness mainline mainlinearrow sidelines
    global commitlisted rowtextx idpos lastuse displist
    global oldnlines olddlevel olddisplist

    incr numcommits
    incr lineno
    set id [lindex $displist $level]
    set lastuse($id) $lineno
    set lineid($lineno) $id
    set idline($id) $lineno
    set ofill [expr {[info exists commitlisted($id)]? "blue": "white"}]
    if {![info exists commitinfo($id)]} {
	readcommit $id
	if {![info exists commitinfo($id)]} {
	    set commitinfo($id) {"No commit information available"}
	    set nparents($id) 0
	}
    }
    assigncolor $id
    set currentparents {}
    set dupparents {}
    if {[info exists commitlisted($id)] && [info exists parents($id)]} {
	foreach p $parents($id) {
	    if {[lsearch -exact $currentparents $p] < 0} {
		lappend currentparents $p
	    } else {
		# remember that this parent was listed twice
		lappend dupparents $p
	    }
	}
    }
    set x [xcoord $level $level $lineno]
    set y1 $canvy
    set canvy [expr $canvy + $linespc]
    allcanvs conf -scrollregion \
	[list 0 0 0 [expr $y1 + 0.5 * $linespc + 2]]
    if {[info exists mainline($id)]} {
	lappend mainline($id) $x $y1
	if {$mainlinearrow($id) ne "none"} {
	    set mainline($id) [trimdiagstart $mainline($id)]
	}
    }
    drawlines $id 0
    set orad [expr {$linespc / 3}]
    set t [$canv create oval [expr $x - $orad] [expr $y1 - $orad] \
	       [expr $x + $orad - 1] [expr $y1 + $orad - 1] \
	       -fill $ofill -outline black -width 1]
    $canv raise $t
    $canv bind $t <1> {selcanvline {} %x %y}
    set xt [xcoord [llength $displist] $level $lineno]
    if {[llength $currentparents] > 2} {
	set xt [expr {$xt + ([llength $currentparents] - 2) * $linespc}]
    }
    set rowtextx($lineno) $xt
    set idpos($id) [list $x $xt $y1]
    if {[info exists idtags($id)] || [info exists idheads($id)]
	|| [info exists idotherrefs($id)]} {
	set xt [drawtags $id $x $xt $y1]
    }
    set headline [lindex $commitinfo($id) 0]
    set name [lindex $commitinfo($id) 1]
    set date [lindex $commitinfo($id) 2]
    set linehtag($lineno) [$canv create text $xt $y1 -anchor w \
			       -text $headline -font $mainfont ]
    $canv bind $linehtag($lineno) <Button-3> "rowmenu %X %Y $id"
    set linentag($lineno) [$canv2 create text 3 $y1 -anchor w \
			       -text $name -font $namefont]
    set linedtag($lineno) [$canv3 create text 3 $y1 -anchor w \
			       -text $date -font $mainfont]

    set olddlevel $level
    set olddisplist $displist
    set oldnlines [llength $displist]
}

proc drawtags {id x xt y1} {
    global idtags idheads idotherrefs
    global linespc lthickness
    global canv mainfont idline rowtextx

    set marks {}
    set ntags 0
    set nheads 0
    if {[info exists idtags($id)]} {
	set marks $idtags($id)
	set ntags [llength $marks]
    }
    if {[info exists idheads($id)]} {
	set marks [concat $marks $idheads($id)]
	set nheads [llength $idheads($id)]
    }
    if {[info exists idotherrefs($id)]} {
	set marks [concat $marks $idotherrefs($id)]
    }
    if {$marks eq {}} {
	return $xt
    }

    set delta [expr {int(0.5 * ($linespc - $lthickness))}]
    set yt [expr $y1 - 0.5 * $linespc]
    set yb [expr $yt + $linespc - 1]
    set xvals {}
    set wvals {}
    foreach tag $marks {
	set wid [font measure $mainfont $tag]
	lappend xvals $xt
	lappend wvals $wid
	set xt [expr {$xt + $delta + $wid + $lthickness + $linespc}]
    }
    set t [$canv create line $x $y1 [lindex $xvals end] $y1 \
	       -width $lthickness -fill black -tags tag.$id]
    $canv lower $t
    foreach tag $marks x $xvals wid $wvals {
	set xl [expr $x + $delta]
	set xr [expr $x + $delta + $wid + $lthickness]
	if {[incr ntags -1] >= 0} {
	    # draw a tag
	    set t [$canv create polygon $x [expr $yt + $delta] $xl $yt \
		       $xr $yt $xr $yb $xl $yb $x [expr $yb - $delta] \
		       -width 1 -outline black -fill yellow -tags tag.$id]
	    $canv bind $t <1> [list showtag $tag 1]
	    set rowtextx($idline($id)) [expr {$xr + $linespc}]
	} else {
	    # draw a head or other ref
	    if {[incr nheads -1] >= 0} {
		set col green
	    } else {
		set col "#ddddff"
	    }
	    set xl [expr $xl - $delta/2]
	    $canv create polygon $x $yt $xr $yt $xr $yb $x $yb \
		-width 1 -outline black -fill $col -tags tag.$id
	}
	set t [$canv create text $xl $y1 -anchor w -text $tag \
		   -font $mainfont -tags tag.$id]
	if {$ntags >= 0} {
	    $canv bind $t <1> [list showtag $tag 1]
	}
    }
    return $xt
}

proc notecrossings {id lo hi corner} {
    global olddisplist crossings cornercrossings

    for {set i $lo} {[incr i] < $hi} {} {
	set p [lindex $olddisplist $i]
	if {$p == {}} continue
	if {$i == $corner} {
	    if {![info exists cornercrossings($id)]
		|| [lsearch -exact $cornercrossings($id) $p] < 0} {
		lappend cornercrossings($id) $p
	    }
	    if {![info exists cornercrossings($p)]
		|| [lsearch -exact $cornercrossings($p) $id] < 0} {
		lappend cornercrossings($p) $id
	    }
	} else {
	    if {![info exists crossings($id)]
		|| [lsearch -exact $crossings($id) $p] < 0} {
		lappend crossings($id) $p
	    }
	    if {![info exists crossings($p)]
		|| [lsearch -exact $crossings($p) $id] < 0} {
		lappend crossings($p) $id
	    }
	}
    }
}

proc xcoord {i level ln} {
    global canvx0 xspc1 xspc2

    set x [expr {$canvx0 + $i * $xspc1($ln)}]
    if {$i > 0 && $i == $level} {
	set x [expr {$x + 0.5 * ($xspc2 - $xspc1($ln))}]
    } elseif {$i > $level} {
	set x [expr {$x + $xspc2 - $xspc1($ln)}]
    }
    return $x
}

# it seems Tk can't draw arrows on the end of diagonal line segments...
proc trimdiagend {line} {
    while {[llength $line] > 4} {
	set x1 [lindex $line end-3]
	set y1 [lindex $line end-2]
	set x2 [lindex $line end-1]
	set y2 [lindex $line end]
	if {($x1 == $x2) != ($y1 == $y2)} break
	set line [lreplace $line end-1 end]
    }
    return $line
}

proc trimdiagstart {line} {
    while {[llength $line] > 4} {
	set x1 [lindex $line 0]
	set y1 [lindex $line 1]
	set x2 [lindex $line 2]
	set y2 [lindex $line 3]
	if {($x1 == $x2) != ($y1 == $y2)} break
	set line [lreplace $line 0 1]
    }
    return $line
}

proc drawslants {id needonscreen nohs} {
    global canv mainline mainlinearrow sidelines
    global canvx0 canvy xspc1 xspc2 lthickness
    global currentparents dupparents
    global lthickness linespc canvy colormap lineno geometry
    global maxgraphpct maxwidth
    global displist onscreen lastuse
    global parents commitlisted
    global oldnlines olddlevel olddisplist
    global nhyperspace numcommits nnewparents

    if {$lineno < 0} {
	lappend displist $id
	set onscreen($id) 1
	return 0
    }

    set y1 [expr {$canvy - $linespc}]
    set y2 $canvy

    # work out what we need to get back on screen
    set reins {}
    if {$onscreen($id) < 0} {
	# next to do isn't displayed, better get it on screen...
	lappend reins [list $id 0]
    }
    # make sure all the previous commits's parents are on the screen
    foreach p $currentparents {
	if {$onscreen($p) < 0} {
	    lappend reins [list $p 0]
	}
    }
    # bring back anything requested by caller
    if {$needonscreen ne {}} {
	lappend reins $needonscreen
    }

    # try the shortcut
    if {$currentparents == $id && $onscreen($id) == 0 && $reins eq {}} {
	set dlevel $olddlevel
	set x [xcoord $dlevel $dlevel $lineno]
	set mainline($id) [list $x $y1]
	set mainlinearrow($id) none
	set lastuse($id) $lineno
	set displist [lreplace $displist $dlevel $dlevel $id]
	set onscreen($id) 1
	set xspc1([expr {$lineno + 1}]) $xspc1($lineno)
	return $dlevel
    }

    # update displist
    set displist [lreplace $displist $olddlevel $olddlevel]
    set j $olddlevel
    foreach p $currentparents {
	set lastuse($p) $lineno
	if {$onscreen($p) == 0} {
	    set displist [linsert $displist $j $p]
	    set onscreen($p) 1
	    incr j
	}
    }
    if {$onscreen($id) == 0} {
	lappend displist $id
	set onscreen($id) 1
    }

    # remove the null entry if present
    set nullentry [lsearch -exact $displist {}]
    if {$nullentry >= 0} {
	set displist [lreplace $displist $nullentry $nullentry]
    }

    # bring back the ones we need now (if we did it earlier
    # it would change displist and invalidate olddlevel)
    foreach pi $reins {
	# test again in case of duplicates in reins
	set p [lindex $pi 0]
	if {$onscreen($p) < 0} {
	    set onscreen($p) 1
	    set lastuse($p) $lineno
	    set displist [linsert $displist [lindex $pi 1] $p]
	    incr nhyperspace -1
	}
    }

    set lastuse($id) $lineno

    # see if we need to make any lines jump off into hyperspace
    set displ [llength $displist]
    if {$displ > $maxwidth} {
	set ages {}
	foreach x $displist {
	    lappend ages [list $lastuse($x) $x]
	}
	set ages [lsort -integer -index 0 $ages]
	set k 0
	while {$displ > $maxwidth} {
	    set use [lindex $ages $k 0]
	    set victim [lindex $ages $k 1]
	    if {$use >= $lineno - 5} break
	    incr k
	    if {[lsearch -exact $nohs $victim] >= 0} continue
	    set i [lsearch -exact $displist $victim]
	    set displist [lreplace $displist $i $i]
	    set onscreen($victim) -1
	    incr nhyperspace
	    incr displ -1
	    if {$i < $nullentry} {
		incr nullentry -1
	    }
	    set x [lindex $mainline($victim) end-1]
	    lappend mainline($victim) $x $y1
	    set line [trimdiagend $mainline($victim)]
	    set arrow "last"
	    if {$mainlinearrow($victim) ne "none"} {
		set line [trimdiagstart $line]
		set arrow "both"
	    }
	    lappend sidelines($victim) [list $line 1 $arrow]
	    unset mainline($victim)
	}
    }

    set dlevel [lsearch -exact $displist $id]

    # If we are reducing, put in a null entry
    if {$displ < $oldnlines} {
	# does the next line look like a merge?
	# i.e. does it have > 1 new parent?
	if {$nnewparents($id) > 1} {
	    set i [expr {$dlevel + 1}]
	} elseif {$nnewparents([lindex $olddisplist $olddlevel]) == 0} {
	    set i $olddlevel
	    if {$nullentry >= 0 && $nullentry < $i} {
		incr i -1
	    }
	} elseif {$nullentry >= 0} {
	    set i $nullentry
	    while {$i < $displ
		   && [lindex $olddisplist $i] == [lindex $displist $i]} {
		incr i
	    }
	} else {
	    set i $olddlevel
	    if {$dlevel >= $i} {
		incr i
	    }
	}
	if {$i < $displ} {
	    set displist [linsert $displist $i {}]
	    incr displ
	    if {$dlevel >= $i} {
		incr dlevel
	    }
	}
    }

    # decide on the line spacing for the next line
    set lj [expr {$lineno + 1}]
    set maxw [expr {$maxgraphpct * $geometry(canv1) / 100}]
    if {$displ <= 1 || $canvx0 + $displ * $xspc2 <= $maxw} {
	set xspc1($lj) $xspc2
    } else {
	set xspc1($lj) [expr {($maxw - $canvx0 - $xspc2) / ($displ - 1)}]
	if {$xspc1($lj) < $lthickness} {
	    set xspc1($lj) $lthickness
	}
    }

    foreach idi $reins {
	set id [lindex $idi 0]
	set j [lsearch -exact $displist $id]
	set xj [xcoord $j $dlevel $lj]
	set mainline($id) [list $xj $y2]
	set mainlinearrow($id) first
    }

    set i -1
    foreach id $olddisplist {
	incr i
	if {$id == {}} continue
	if {$onscreen($id) <= 0} continue
	set xi [xcoord $i $olddlevel $lineno]
	if {$i == $olddlevel} {
	    foreach p $currentparents {
		set j [lsearch -exact $displist $p]
		set coords [list $xi $y1]
		set xj [xcoord $j $dlevel $lj]
		if {$xj < $xi - $linespc} {
		    lappend coords [expr {$xj + $linespc}] $y1
		    notecrossings $p $j $i [expr {$j + 1}]
		} elseif {$xj > $xi + $linespc} {
		    lappend coords [expr {$xj - $linespc}] $y1
		    notecrossings $p $i $j [expr {$j - 1}]
		}
		if {[lsearch -exact $dupparents $p] >= 0} {
		    # draw a double-width line to indicate the doubled parent
		    lappend coords $xj $y2
		    lappend sidelines($p) [list $coords 2 none]
		    if {![info exists mainline($p)]} {
			set mainline($p) [list $xj $y2]
			set mainlinearrow($p) none
		    }
		} else {
		    # normal case, no parent duplicated
		    set yb $y2
		    set dx [expr {abs($xi - $xj)}]
		    if {0 && $dx < $linespc} {
			set yb [expr {$y1 + $dx}]
		    }
		    if {![info exists mainline($p)]} {
			if {$xi != $xj} {
			    lappend coords $xj $yb
			}
			set mainline($p) $coords
			set mainlinearrow($p) none
		    } else {
			lappend coords $xj $yb
			if {$yb < $y2} {
			    lappend coords $xj $y2
			}
			lappend sidelines($p) [list $coords 1 none]
		    }
		}
	    }
	} else {
	    set j $i
	    if {[lindex $displist $i] != $id} {
		set j [lsearch -exact $displist $id]
	    }
	    if {$j != $i || $xspc1($lineno) != $xspc1($lj)
		|| ($olddlevel < $i && $i < $dlevel)
		|| ($dlevel < $i && $i < $olddlevel)} {
		set xj [xcoord $j $dlevel $lj]
		lappend mainline($id) $xi $y1 $xj $y2
	    }
	}
    }
    return $dlevel
}

# search for x in a list of lists
proc llsearch {llist x} {
    set i 0
    foreach l $llist {
	if {$l == $x || [lsearch -exact $l $x] >= 0} {
	    return $i
	}
	incr i
    }
    return -1
}

proc drawmore {reading} {
    global displayorder numcommits ncmupdate nextupdate
    global stopped nhyperspace parents commitlisted
    global maxwidth onscreen displist currentparents olddlevel

    set n [llength $displayorder]
    while {$numcommits < $n} {
	set id [lindex $displayorder $numcommits]
	set ctxend [expr {$numcommits + 10}]
	if {!$reading && $ctxend > $n} {
	    set ctxend $n
	}
	set dlist {}
	if {$numcommits > 0} {
	    set dlist [lreplace $displist $olddlevel $olddlevel]
	    set i $olddlevel
	    foreach p $currentparents {
		if {$onscreen($p) == 0} {
		    set dlist [linsert $dlist $i $p]
		    incr i
		}
	    }
	}
	set nohs {}
	set reins {}
	set isfat [expr {[llength $dlist] > $maxwidth}]
	if {$nhyperspace > 0 || $isfat} {
	    if {$ctxend > $n} break
	    # work out what to bring back and
	    # what we want to don't want to send into hyperspace
	    set room 1
	    for {set k $numcommits} {$k < $ctxend} {incr k} {
		set x [lindex $displayorder $k]
		set i [llsearch $dlist $x]
		if {$i < 0} {
		    set i [llength $dlist]
		    lappend dlist $x
		}
		if {[lsearch -exact $nohs $x] < 0} {
		    lappend nohs $x
		}
		if {$reins eq {} && $onscreen($x) < 0 && $room} {
		    set reins [list $x $i]
		}
		set newp {}
		if {[info exists commitlisted($x)]} {
		    set right 0
		    foreach p $parents($x) {
			if {[llsearch $dlist $p] < 0} {
			    lappend newp $p
			    if {[lsearch -exact $nohs $p] < 0} {
				lappend nohs $p
			    }
			    if {$reins eq {} && $onscreen($p) < 0 && $room} {
				set reins [list $p [expr {$i + $right}]]
			    }
			}
			set right 1
		    }
		}
		set l [lindex $dlist $i]
		if {[llength $l] == 1} {
		    set l $newp
		} else {
		    set j [lsearch -exact $l $x]
		    set l [concat [lreplace $l $j $j] $newp]
		}
		set dlist [lreplace $dlist $i $i $l]
		if {$room && $isfat && [llength $newp] <= 1} {
		    set room 0
		}
	    }
	}

	set dlevel [drawslants $id $reins $nohs]
	drawcommitline $dlevel
	if {[clock clicks -milliseconds] >= $nextupdate
	    && $numcommits >= $ncmupdate} {
	    doupdate $reading
	    if {$stopped} break
	}
    }
}

# level here is an index in todo
proc updatetodo {level noshortcut} {
    global ncleft todo nnewparents
    global commitlisted parents onscreen

    set id [lindex $todo $level]
    set olds {}
    if {[info exists commitlisted($id)]} {
	foreach p $parents($id) {
	    if {[lsearch -exact $olds $p] < 0} {
		lappend olds $p
	    }
	}
    }
    if {!$noshortcut && [llength $olds] == 1} {
	set p [lindex $olds 0]
	if {$ncleft($p) == 1 && [lsearch -exact $todo $p] < 0} {
	    set ncleft($p) 0
	    set todo [lreplace $todo $level $level $p]
	    set onscreen($p) 0
	    set nnewparents($id) 1
	    return 0
	}
    }

    set todo [lreplace $todo $level $level]
    set i $level
    set n 0
    foreach p $olds {
	incr ncleft($p) -1
	set k [lsearch -exact $todo $p]
	if {$k < 0} {
	    set todo [linsert $todo $i $p]
	    set onscreen($p) 0
	    incr i
	    incr n
	}
    }
    set nnewparents($id) $n

    return 1
}

proc decidenext {{noread 0}} {
    global ncleft todo
    global datemode cdate
    global commitinfo

    # choose which one to do next time around
    set todol [llength $todo]
    set level -1
    set latest {}
    for {set k $todol} {[incr k -1] >= 0} {} {
	set p [lindex $todo $k]
	if {$ncleft($p) == 0} {
	    if {$datemode} {
		if {![info exists commitinfo($p)]} {
		    if {$noread} {
			return {}
		    }
		    readcommit $p
		}
		if {$latest == {} || $cdate($p) > $latest} {
		    set level $k
		    set latest $cdate($p)
		}
	    } else {
		set level $k
		break
	    }
	}
    }
    if {$level < 0} {
	if {$todo != {}} {
	    puts "ERROR: none of the pending commits can be done yet:"
	    foreach p $todo {
		puts "  $p ($ncleft($p))"
	    }
	}
	return -1
    }

    return $level
}

proc drawcommit {id} {
    global phase todo nchildren datemode nextupdate
    global numcommits ncmupdate displayorder todo onscreen

    if {$phase != "incrdraw"} {
	set phase incrdraw
	set displayorder {}
	set todo {}
	initgraph
    }
    if {$nchildren($id) == 0} {
	lappend todo $id
	set onscreen($id) 0
    }
    set level [decidenext 1]
    if {$level == {} || $id != [lindex $todo $level]} {
	return
    }
    while 1 {
	lappend displayorder [lindex $todo $level]
	if {[updatetodo $level $datemode]} {
	    set level [decidenext 1]
	    if {$level == {}} break
	}
	set id [lindex $todo $level]
	if {![info exists commitlisted($id)]} {
	    break
	}
    }
    drawmore 1
}

proc finishcommits {} {
    global phase
    global canv mainfont ctext maincursor textcursor

    if {$phase != "incrdraw"} {
	$canv delete all
	$canv create text 3 3 -anchor nw -text "No commits selected" \
	    -font $mainfont -tags textitems
	set phase {}
    } else {
	drawrest
    }
    . config -cursor $maincursor
    settextcursor $textcursor
}

# Don't change the text pane cursor if it is currently the hand cursor,
# showing that we are over a sha1 ID link.
proc settextcursor {c} {
    global ctext curtextcursor

    if {[$ctext cget -cursor] == $curtextcursor} {
	$ctext config -cursor $c
    }
    set curtextcursor $c
}

proc drawgraph {} {
    global nextupdate startmsecs ncmupdate
    global displayorder onscreen

    if {$displayorder == {}} return
    set startmsecs [clock clicks -milliseconds]
    set nextupdate [expr $startmsecs + 100]
    set ncmupdate 1
    initgraph
    foreach id $displayorder {
	set onscreen($id) 0
    }
    drawmore 0
}

proc drawrest {} {
    global phase stopped redisplaying selectedline
    global datemode todo displayorder
    global numcommits ncmupdate
    global nextupdate startmsecs

    set level [decidenext]
    if {$level >= 0} {
	set phase drawgraph
	while 1 {
	    lappend displayorder [lindex $todo $level]
	    set hard [updatetodo $level $datemode]
	    if {$hard} {
		set level [decidenext]
		if {$level < 0} break
	    }
	}
	drawmore 0
    }
    set phase {}
    set drawmsecs [expr [clock clicks -milliseconds] - $startmsecs]
    #puts "overall $drawmsecs ms for $numcommits commits"
    if {$redisplaying} {
	if {$stopped == 0 && [info exists selectedline]} {
	    selectline $selectedline 0
	}
	if {$stopped == 1} {
	    set stopped 0
	    after idle drawgraph
	} else {
	    set redisplaying 0
	}
    }
}

proc findmatches {f} {
    global findtype foundstring foundstrlen
    if {$findtype == "Regexp"} {
	set matches [regexp -indices -all -inline $foundstring $f]
    } else {
	if {$findtype == "IgnCase"} {
	    set str [string tolower $f]
	} else {
	    set str $f
	}
	set matches {}
	set i 0
	while {[set j [string first $foundstring $str $i]] >= 0} {
	    lappend matches [list $j [expr $j+$foundstrlen-1]]
	    set i [expr $j + $foundstrlen]
	}
    }
    return $matches
}

proc dofind {} {
    global findtype findloc findstring markedmatches commitinfo
    global numcommits lineid linehtag linentag linedtag
    global mainfont namefont canv canv2 canv3 selectedline
    global matchinglines foundstring foundstrlen

    stopfindproc
    unmarkmatches
    focus .
    set matchinglines {}
    if {$findloc == "Pickaxe"} {
	findpatches
	return
    }
    if {$findtype == "IgnCase"} {
	set foundstring [string tolower $findstring]
    } else {
	set foundstring $findstring
    }
    set foundstrlen [string length $findstring]
    if {$foundstrlen == 0} return
    if {$findloc == "Files"} {
	findfiles
	return
    }
    if {![info exists selectedline]} {
	set oldsel -1
    } else {
	set oldsel $selectedline
    }
    set didsel 0
    set fldtypes {Headline Author Date Committer CDate Comment}
    for {set l 0} {$l < $numcommits} {incr l} {
	set id $lineid($l)
	set info $commitinfo($id)
	set doesmatch 0
	foreach f $info ty $fldtypes {
	    if {$findloc != "All fields" && $findloc != $ty} {
		continue
	    }
	    set matches [findmatches $f]
	    if {$matches == {}} continue
	    set doesmatch 1
	    if {$ty == "Headline"} {
		markmatches $canv $l $f $linehtag($l) $matches $mainfont
	    } elseif {$ty == "Author"} {
		markmatches $canv2 $l $f $linentag($l) $matches $namefont
	    } elseif {$ty == "Date"} {
		markmatches $canv3 $l $f $linedtag($l) $matches $mainfont
	    }
	}
	if {$doesmatch} {
	    lappend matchinglines $l
	    if {!$didsel && $l > $oldsel} {
		findselectline $l
		set didsel 1
	    }
	}
    }
    if {$matchinglines == {}} {
	bell
    } elseif {!$didsel} {
	findselectline [lindex $matchinglines 0]
    }
}

proc findselectline {l} {
    global findloc commentend ctext
    selectline $l 1
    if {$findloc == "All fields" || $findloc == "Comments"} {
	# highlight the matches in the comments
	set f [$ctext get 1.0 $commentend]
	set matches [findmatches $f]
	foreach match $matches {
	    set start [lindex $match 0]
	    set end [expr [lindex $match 1] + 1]
	    $ctext tag add found "1.0 + $start c" "1.0 + $end c"
	}
    }
}

proc findnext {restart} {
    global matchinglines selectedline
    if {![info exists matchinglines]} {
	if {$restart} {
	    dofind
	}
	return
    }
    if {![info exists selectedline]} return
    foreach l $matchinglines {
	if {$l > $selectedline} {
	    findselectline $l
	    return
	}
    }
    bell
}

proc findprev {} {
    global matchinglines selectedline
    if {![info exists matchinglines]} {
	dofind
	return
    }
    if {![info exists selectedline]} return
    set prev {}
    foreach l $matchinglines {
	if {$l >= $selectedline} break
	set prev $l
    }
    if {$prev != {}} {
	findselectline $prev
    } else {
	bell
    }
}

proc findlocchange {name ix op} {
    global findloc findtype findtypemenu
    if {$findloc == "Pickaxe"} {
	set findtype Exact
	set state disabled
    } else {
	set state normal
    }
    $findtypemenu entryconf 1 -state $state
    $findtypemenu entryconf 2 -state $state
}

proc stopfindproc {{done 0}} {
    global findprocpid findprocfile findids
    global ctext findoldcursor phase maincursor textcursor
    global findinprogress

    catch {unset findids}
    if {[info exists findprocpid]} {
	if {!$done} {
	    catch {exec kill $findprocpid}
	}
	catch {close $findprocfile}
	unset findprocpid
    }
    if {[info exists findinprogress]} {
	unset findinprogress
	if {$phase != "incrdraw"} {
	    . config -cursor $maincursor
	    settextcursor $textcursor
	}
    }
}

proc findpatches {} {
    global findstring selectedline numcommits
    global findprocpid findprocfile
    global finddidsel ctext lineid findinprogress
    global findinsertpos

    if {$numcommits == 0} return

    # make a list of all the ids to search, starting at the one
    # after the selected line (if any)
    if {[info exists selectedline]} {
	set l $selectedline
    } else {
	set l -1
    }
    set inputids {}
    for {set i 0} {$i < $numcommits} {incr i} {
	if {[incr l] >= $numcommits} {
	    set l 0
	}
	append inputids $lineid($l) "\n"
    }

    if {[catch {
	set f [open [list | git-diff-tree --stdin -s -r -S$findstring \
			 << $inputids] r]
    } err]} {
	error_popup "Error starting search process: $err"
	return
    }

    set findinsertpos end
    set findprocfile $f
    set findprocpid [pid $f]
    fconfigure $f -blocking 0
    fileevent $f readable readfindproc
    set finddidsel 0
    . config -cursor watch
    settextcursor watch
    set findinprogress 1
}

proc readfindproc {} {
    global findprocfile finddidsel
    global idline matchinglines findinsertpos

    set n [gets $findprocfile line]
    if {$n < 0} {
	if {[eof $findprocfile]} {
	    stopfindproc 1
	    if {!$finddidsel} {
		bell
	    }
	}
	return
    }
    if {![regexp {^[0-9a-f]{40}} $line id]} {
	error_popup "Can't parse git-diff-tree output: $line"
	stopfindproc
	return
    }
    if {![info exists idline($id)]} {
	puts stderr "spurious id: $id"
	return
    }
    set l $idline($id)
    insertmatch $l $id
}

proc insertmatch {l id} {
    global matchinglines findinsertpos finddidsel

    if {$findinsertpos == "end"} {
	if {$matchinglines != {} && $l < [lindex $matchinglines 0]} {
	    set matchinglines [linsert $matchinglines 0 $l]
	    set findinsertpos 1
	} else {
	    lappend matchinglines $l
	}
    } else {
	set matchinglines [linsert $matchinglines $findinsertpos $l]
	incr findinsertpos
    }
    markheadline $l $id
    if {!$finddidsel} {
	findselectline $l
	set finddidsel 1
    }
}

proc findfiles {} {
    global selectedline numcommits lineid ctext
    global ffileline finddidsel parents nparents
    global findinprogress findstartline findinsertpos
    global treediffs fdiffids fdiffsneeded fdiffpos
    global findmergefiles

    if {$numcommits == 0} return

    if {[info exists selectedline]} {
	set l [expr {$selectedline + 1}]
    } else {
	set l 0
    }
    set ffileline $l
    set findstartline $l
    set diffsneeded {}
    set fdiffsneeded {}
    while 1 {
	set id $lineid($l)
	if {$findmergefiles || $nparents($id) == 1} {
	    foreach p $parents($id) {
		if {![info exists treediffs([list $id $p])]} {
		    append diffsneeded "$id $p\n"
		    lappend fdiffsneeded [list $id $p]
		}
	    }
	}
	if {[incr l] >= $numcommits} {
	    set l 0
	}
	if {$l == $findstartline} break
    }

    # start off a git-diff-tree process if needed
    if {$diffsneeded ne {}} {
	if {[catch {
	    set df [open [list | git-diff-tree -r --stdin << $diffsneeded] r]
	} err ]} {
	    error_popup "Error starting search process: $err"
	    return
	}
	catch {unset fdiffids}
	set fdiffpos 0
	fconfigure $df -blocking 0
	fileevent $df readable [list readfilediffs $df]
    }

    set finddidsel 0
    set findinsertpos end
    set id $lineid($l)
    set p [lindex $parents($id) 0]
    . config -cursor watch
    settextcursor watch
    set findinprogress 1
    findcont [list $id $p]
    update
}

proc readfilediffs {df} {
    global findids fdiffids fdiffs

    set n [gets $df line]
    if {$n < 0} {
	if {[eof $df]} {
	    donefilediff
	    if {[catch {close $df} err]} {
		stopfindproc
		bell
		error_popup "Error in git-diff-tree: $err"
	    } elseif {[info exists findids]} {
		set ids $findids
		stopfindproc
		bell
		error_popup "Couldn't find diffs for {$ids}"
	    }
	}
	return
    }
    if {[regexp {^([0-9a-f]{40}) \(from ([0-9a-f]{40})\)} $line match id p]} {
	# start of a new string of diffs
	donefilediff
	set fdiffids [list $id $p]
	set fdiffs {}
    } elseif {[string match ":*" $line]} {
	lappend fdiffs [lindex $line 5]
    }
}

proc donefilediff {} {
    global fdiffids fdiffs treediffs findids
    global fdiffsneeded fdiffpos

    if {[info exists fdiffids]} {
	while {[lindex $fdiffsneeded $fdiffpos] ne $fdiffids
	       && $fdiffpos < [llength $fdiffsneeded]} {
	    # git-diff-tree doesn't output anything for a commit
	    # which doesn't change anything
	    set nullids [lindex $fdiffsneeded $fdiffpos]
	    set treediffs($nullids) {}
	    if {[info exists findids] && $nullids eq $findids} {
		unset findids
		findcont $nullids
	    }
	    incr fdiffpos
	}
	incr fdiffpos

	if {![info exists treediffs($fdiffids)]} {
	    set treediffs($fdiffids) $fdiffs
	}
	if {[info exists findids] && $fdiffids eq $findids} {
	    unset findids
	    findcont $fdiffids
	}
    }
}

proc findcont {ids} {
    global findids treediffs parents nparents
    global ffileline findstartline finddidsel
    global lineid numcommits matchinglines findinprogress
    global findmergefiles

    set id [lindex $ids 0]
    set p [lindex $ids 1]
    set pi [lsearch -exact $parents($id) $p]
    set l $ffileline
    while 1 {
	if {$findmergefiles || $nparents($id) == 1} {
	    if {![info exists treediffs($ids)]} {
		set findids $ids
		set ffileline $l
		return
	    }
	    set doesmatch 0
	    foreach f $treediffs($ids) {
		set x [findmatches $f]
		if {$x != {}} {
		    set doesmatch 1
		    break
		}
	    }
	    if {$doesmatch} {
		insertmatch $l $id
		set pi $nparents($id)
	    }
	} else {
	    set pi $nparents($id)
	}
	if {[incr pi] >= $nparents($id)} {
	    set pi 0
	    if {[incr l] >= $numcommits} {
		set l 0
	    }
	    if {$l == $findstartline} break
	    set id $lineid($l)
	}
	set p [lindex $parents($id) $pi]
	set ids [list $id $p]
    }
    stopfindproc
    if {!$finddidsel} {
	bell
    }
}

# mark a commit as matching by putting a yellow background
# behind the headline
proc markheadline {l id} {
    global canv mainfont linehtag commitinfo

    set bbox [$canv bbox $linehtag($l)]
    set t [$canv create rect $bbox -outline {} -tags matches -fill yellow]
    $canv lower $t
}

# mark the bits of a headline, author or date that match a find string
proc markmatches {canv l str tag matches font} {
    set bbox [$canv bbox $tag]
    set x0 [lindex $bbox 0]
    set y0 [lindex $bbox 1]
    set y1 [lindex $bbox 3]
    foreach match $matches {
	set start [lindex $match 0]
	set end [lindex $match 1]
	if {$start > $end} continue
	set xoff [font measure $font [string range $str 0 [expr $start-1]]]
	set xlen [font measure $font [string range $str 0 [expr $end]]]
	set t [$canv create rect [expr $x0+$xoff] $y0 [expr $x0+$xlen+2] $y1 \
		   -outline {} -tags matches -fill yellow]
	$canv lower $t
    }
}

proc unmarkmatches {} {
    global matchinglines findids
    allcanvs delete matches
    catch {unset matchinglines}
    catch {unset findids}
}

proc selcanvline {w x y} {
    global canv canvy0 ctext linespc
    global lineid linehtag linentag linedtag rowtextx
    set ymax [lindex [$canv cget -scrollregion] 3]
    if {$ymax == {}} return
    set yfrac [lindex [$canv yview] 0]
    set y [expr {$y + $yfrac * $ymax}]
    set l [expr {int(($y - $canvy0) / $linespc + 0.5)}]
    if {$l < 0} {
	set l 0
    }
    if {$w eq $canv} {
	if {![info exists rowtextx($l)] || $x < $rowtextx($l)} return
    }
    unmarkmatches
    selectline $l 1
}

proc commit_descriptor {p} {
    global commitinfo
    set l "..."
    if {[info exists commitinfo($p)]} {
	set l [lindex $commitinfo($p) 0]
    }
    return "$p ($l)"
}

# append some text to the ctext widget, and make any SHA1 ID
# that we know about be a clickable link.
proc appendwithlinks {text} {
    global ctext idline linknum

    set start [$ctext index "end - 1c"]
    $ctext insert end $text
    $ctext insert end "\n"
    set links [regexp -indices -all -inline {[0-9a-f]{40}} $text]
    foreach l $links {
	set s [lindex $l 0]
	set e [lindex $l 1]
	set linkid [string range $text $s $e]
	if {![info exists idline($linkid)]} continue
	incr e
	$ctext tag add link "$start + $s c" "$start + $e c"
	$ctext tag add link$linknum "$start + $s c" "$start + $e c"
	$ctext tag bind link$linknum <1> [list selectline $idline($linkid) 1]
	incr linknum
    }
    $ctext tag conf link -foreground blue -underline 1
    $ctext tag bind link <Enter> { %W configure -cursor hand2 }
    $ctext tag bind link <Leave> { %W configure -cursor $curtextcursor }
}

proc selectline {l isnew} {
    global canv canv2 canv3 ctext commitinfo selectedline
    global lineid linehtag linentag linedtag
    global canvy0 linespc parents nparents children
    global cflist currentid sha1entry
    global commentend idtags idline linknum

    $canv delete hover
    normalline
    if {![info exists lineid($l)] || ![info exists linehtag($l)]} return
    $canv delete secsel
    set t [eval $canv create rect [$canv bbox $linehtag($l)] -outline {{}} \
	       -tags secsel -fill [$canv cget -selectbackground]]
    $canv lower $t
    $canv2 delete secsel
    set t [eval $canv2 create rect [$canv2 bbox $linentag($l)] -outline {{}} \
	       -tags secsel -fill [$canv2 cget -selectbackground]]
    $canv2 lower $t
    $canv3 delete secsel
    set t [eval $canv3 create rect [$canv3 bbox $linedtag($l)] -outline {{}} \
	       -tags secsel -fill [$canv3 cget -selectbackground]]
    $canv3 lower $t
    set y [expr {$canvy0 + $l * $linespc}]
    set ymax [lindex [$canv cget -scrollregion] 3]
    set ytop [expr {$y - $linespc - 1}]
    set ybot [expr {$y + $linespc + 1}]
    set wnow [$canv yview]
    set wtop [expr [lindex $wnow 0] * $ymax]
    set wbot [expr [lindex $wnow 1] * $ymax]
    set wh [expr {$wbot - $wtop}]
    set newtop $wtop
    if {$ytop < $wtop} {
	if {$ybot < $wtop} {
	    set newtop [expr {$y - $wh / 2.0}]
	} else {
	    set newtop $ytop
	    if {$newtop > $wtop - $linespc} {
		set newtop [expr {$wtop - $linespc}]
	    }
	}
    } elseif {$ybot > $wbot} {
	if {$ytop > $wbot} {
	    set newtop [expr {$y - $wh / 2.0}]
	} else {
	    set newtop [expr {$ybot - $wh}]
	    if {$newtop < $wtop + $linespc} {
		set newtop [expr {$wtop + $linespc}]
	    }
	}
    }
    if {$newtop != $wtop} {
	if {$newtop < 0} {
	    set newtop 0
	}
	allcanvs yview moveto [expr $newtop * 1.0 / $ymax]
    }

    if {$isnew} {
	addtohistory [list selectline $l 0]
    }

    set selectedline $l

    set id $lineid($l)
    set currentid $id
    $sha1entry delete 0 end
    $sha1entry insert 0 $id
    $sha1entry selection from 0
    $sha1entry selection to end

    $ctext conf -state normal
    $ctext delete 0.0 end
    set linknum 0
    $ctext mark set fmark.0 0.0
    $ctext mark gravity fmark.0 left
    set info $commitinfo($id)
    $ctext insert end "Author: [lindex $info 1]  [lindex $info 2]\n"
    $ctext insert end "Committer: [lindex $info 3]  [lindex $info 4]\n"
    if {[info exists idtags($id)]} {
	$ctext insert end "Tags:"
	foreach tag $idtags($id) {
	    $ctext insert end " $tag"
	}
	$ctext insert end "\n"
    }
 
    set comment {}
    if {[info exists parents($id)]} {
	foreach p $parents($id) {
	    append comment "Parent: [commit_descriptor $p]\n"
	}
    }
    if {[info exists children($id)]} {
	foreach c $children($id) {
	    append comment "Child:  [commit_descriptor $c]\n"
	}
    }
    append comment "\n"
    append comment [lindex $info 5]

    # make anything that looks like a SHA1 ID be a clickable link
    appendwithlinks $comment

    $ctext tag delete Comments
    $ctext tag remove found 1.0 end
    $ctext conf -state disabled
    set commentend [$ctext index "end - 1c"]

    $cflist delete 0 end
    $cflist insert end "Comments"
    if {$nparents($id) == 1} {
	startdiff [concat $id $parents($id)]
    } elseif {$nparents($id) > 1} {
	mergediff $id
    }
}

proc selnextline {dir} {
    global selectedline
    if {![info exists selectedline]} return
    set l [expr $selectedline + $dir]
    unmarkmatches
    selectline $l 1
}

proc unselectline {} {
    global selectedline

    catch {unset selectedline}
    allcanvs delete secsel
}

proc addtohistory {cmd} {
    global history historyindex

    if {$historyindex > 0
	&& [lindex $history [expr {$historyindex - 1}]] == $cmd} {
	return
    }

    if {$historyindex < [llength $history]} {
	set history [lreplace $history $historyindex end $cmd]
    } else {
	lappend history $cmd
    }
    incr historyindex
    if {$historyindex > 1} {
	.ctop.top.bar.leftbut conf -state normal
    } else {
	.ctop.top.bar.leftbut conf -state disabled
    }
    .ctop.top.bar.rightbut conf -state disabled
}

proc goback {} {
    global history historyindex

    if {$historyindex > 1} {
	incr historyindex -1
	set cmd [lindex $history [expr {$historyindex - 1}]]
	eval $cmd
	.ctop.top.bar.rightbut conf -state normal
    }
    if {$historyindex <= 1} {
	.ctop.top.bar.leftbut conf -state disabled
    }
}

proc goforw {} {
    global history historyindex

    if {$historyindex < [llength $history]} {
	set cmd [lindex $history $historyindex]
	incr historyindex
	eval $cmd
	.ctop.top.bar.leftbut conf -state normal
    }
    if {$historyindex >= [llength $history]} {
	.ctop.top.bar.rightbut conf -state disabled
    }
}

proc mergediff {id} {
    global parents diffmergeid diffmergegca mergefilelist diffpindex

    set diffmergeid $id
    set diffpindex -1
    set diffmergegca [findgca $parents($id)]
    if {[info exists mergefilelist($id)]} {
	if {$mergefilelist($id) ne {}} {
	    showmergediff
	}
    } else {
	contmergediff {}
    }
}

proc findgca {ids} {
    set gca {}
    foreach id $ids {
	if {$gca eq {}} {
	    set gca $id
	} else {
	    if {[catch {
		set gca [exec git-merge-base $gca $id]
	    } err]} {
		return {}
	    }
	}
    }
    return $gca
}

proc contmergediff {ids} {
    global diffmergeid diffpindex parents nparents diffmergegca
    global treediffs mergefilelist diffids treepending

    # diff the child against each of the parents, and diff
    # each of the parents against the GCA.
    while 1 {
	if {[lindex $ids 0] == $diffmergeid && $diffmergegca ne {}} {
	    set ids [list [lindex $ids 1] $diffmergegca]
	} else {
	    if {[incr diffpindex] >= $nparents($diffmergeid)} break
	    set p [lindex $parents($diffmergeid) $diffpindex]
	    set ids [list $diffmergeid $p]
	}
	if {![info exists treediffs($ids)]} {
	    set diffids $ids
	    if {![info exists treepending]} {
		gettreediffs $ids
	    }
	    return
	}
    }

    # If a file in some parent is different from the child and also
    # different from the GCA, then it's interesting.
    # If we don't have a GCA, then a file is interesting if it is
    # different from the child in all the parents.
    if {$diffmergegca ne {}} {
	set files {}
	foreach p $parents($diffmergeid) {
	    set gcadiffs $treediffs([list $p $diffmergegca])
	    foreach f $treediffs([list $diffmergeid $p]) {
		if {[lsearch -exact $files $f] < 0
		    && [lsearch -exact $gcadiffs $f] >= 0} {
		    lappend files $f
		}
	    }
	}
	set files [lsort $files]
    } else {
	set p [lindex $parents($diffmergeid) 0]
	set files $treediffs([list $diffmergeid $p])
	for {set i 1} {$i < $nparents($diffmergeid) && $files ne {}} {incr i} {
	    set p [lindex $parents($diffmergeid) $i]
	    set df $treediffs([list $diffmergeid $p])
	    set nf {}
	    foreach f $files {
		if {[lsearch -exact $df $f] >= 0} {
		    lappend nf $f
		}
	    }
	    set files $nf
	}
    }

    set mergefilelist($diffmergeid) $files
    if {$files ne {}} {
	showmergediff
    }
}

proc showmergediff {} {
    global cflist diffmergeid mergefilelist parents
    global diffopts diffinhunk currentfile currenthunk filelines
    global diffblocked groupfilelast mergefds groupfilenum grouphunks

    set files $mergefilelist($diffmergeid)
    foreach f $files {
	$cflist insert end $f
    }
    set env(GIT_DIFF_OPTS) $diffopts
    set flist {}
    catch {unset currentfile}
    catch {unset currenthunk}
    catch {unset filelines}
    catch {unset groupfilenum}
    catch {unset grouphunks}
    set groupfilelast -1
    foreach p $parents($diffmergeid) {
	set cmd [list | git-diff-tree -p $p $diffmergeid]
	set cmd [concat $cmd $mergefilelist($diffmergeid)]
	if {[catch {set f [open $cmd r]} err]} {
	    error_popup "Error getting diffs: $err"
	    foreach f $flist {
		catch {close $f}
	    }
	    return
	}
	lappend flist $f
	set ids [list $diffmergeid $p]
	set mergefds($ids) $f
	set diffinhunk($ids) 0
	set diffblocked($ids) 0
	fconfigure $f -blocking 0
	fileevent $f readable [list getmergediffline $f $ids $diffmergeid]
    }
}

proc getmergediffline {f ids id} {
    global diffmergeid diffinhunk diffoldlines diffnewlines
    global currentfile currenthunk
    global diffoldstart diffnewstart diffoldlno diffnewlno
    global diffblocked mergefilelist
    global noldlines nnewlines difflcounts filelines

    set n [gets $f line]
    if {$n < 0} {
	if {![eof $f]} return
    }

    if {!([info exists diffmergeid] && $diffmergeid == $id)} {
	if {$n < 0} {
	    close $f
	}
	return
    }

    if {$diffinhunk($ids) != 0} {
	set fi $currentfile($ids)
	if {$n > 0 && [regexp {^[-+ \\]} $line match]} {
	    # continuing an existing hunk
	    set line [string range $line 1 end]
	    set p [lindex $ids 1]
	    if {$match eq "-" || $match eq " "} {
		set filelines($p,$fi,$diffoldlno($ids)) $line
		incr diffoldlno($ids)
	    }
	    if {$match eq "+" || $match eq " "} {
		set filelines($id,$fi,$diffnewlno($ids)) $line
		incr diffnewlno($ids)
	    }
	    if {$match eq " "} {
		if {$diffinhunk($ids) == 2} {
		    lappend difflcounts($ids) \
			[list $noldlines($ids) $nnewlines($ids)]
		    set noldlines($ids) 0
		    set diffinhunk($ids) 1
		}
		incr noldlines($ids)
	    } elseif {$match eq "-" || $match eq "+"} {
		if {$diffinhunk($ids) == 1} {
		    lappend difflcounts($ids) [list $noldlines($