hgk: add horizontal scrollbar to patch window

contrib/hgk

@@ -1,3650 +1,3653 b''
 #!/usr/bin/env wish
 
 # 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 ".hg"
     }
 }
 
 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 hg debug-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 "|hg debug-rev-list --header --topo-order --parents $parsed_args" r]
     } err] {
 	puts stderr "Error executing hg debug-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 $shortcmit 0 80]..."
 	    }
 	    error_popup "Can't parse hg debug-rev-list output: {$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 hg debug-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 [exec hg tags]
     set lines [split $tags '\n']
     foreach f $lines {
 	set f [regexp -all -inline {\S+} $f]
 	set direct [lindex $f 0]
 	set full [lindex $f 1]
 	set sha [split $full ':']
 	set tag [lindex $sha 1]
 	lappend tagids($direct) $tag
 	lappend idtags($tag) $direct
     }
 }
 
 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 $geometry(ctexth) \
-	-yscrollcommand ".ctop.cdet.left.sb set" -wrap none
+	-yscrollcommand ".ctop.cdet.left.sb set" \
+	-xscrollcommand ".ctop.cdet.left.hb set" -wrap none
     scrollbar .ctop.cdet.left.sb -command "$ctext yview"
+    scrollbar .ctop.cdet.left.hb -orient horizontal -command "$ctext xview"
     pack .ctop.cdet.left.sb -side right -fill y
+    pack .ctop.cdet.left.hb -side bottom -fill x
     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-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> "$ctext yview scroll 1 pages"
     bindkey p "selnextline -1"
     bindkey n "selnextline 1"
     bindkey b "$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-w> 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 | hg debug-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 | hg debug-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 hg debug-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 hg debug-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 | hg debug-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 $noldlines($ids)]
 		    set noldlines($ids) 0
 		    set nnewlines($ids) 0
 		    set diffinhunk($ids) 2
 		}
 		if {$match eq "-"} {
 		    incr noldlines($ids)
 		} else {
 		    incr nnewlines($ids)
 		}
 	    }
 	    # and if it's \ No newline at end of line, then what?
 	    return
 	}
 	# end of a hunk
 	if {$diffinhunk($ids) == 1 && $noldlines($ids) != 0} {
 	    lappend difflcounts($ids) [list $noldlines($ids)]
 	} elseif {$diffinhunk($ids) == 2
 		  && ($noldlines($ids) != 0 || $nnewlines($ids) != 0)} {
 	    lappend difflcounts($ids) [list $noldlines($ids) $nnewlines($ids)]
 	}
 	set currenthunk($ids) [list $currentfile($ids) \
 				   $diffoldstart($ids) $diffnewstart($ids) \
 				   $diffoldlno($ids) $diffnewlno($ids) \
 				   $difflcounts($ids)]
 	set diffinhunk($ids) 0
 	# -1 = need to block, 0 = unblocked, 1 = is blocked
 	set diffblocked($ids) -1
 	processhunks
 	if {$diffblocked($ids) == -1} {
 	    fileevent $f readable {}
 	    set diffblocked($ids) 1
 	}
     }
 
     if {$n < 0} {
 	# eof
 	if {!$diffblocked($ids)} {
 	    close $f
 	    set currentfile($ids) [llength $mergefilelist($diffmergeid)]
 	    set currenthunk($ids) [list $currentfile($ids) 0 0 0 0 {}]
 	    processhunks
 	}
     } elseif {[regexp {^diff --git a/(.*) b/} $line match fname]} {
 	# start of a new file
 	set currentfile($ids) \
 	    [lsearch -exact $mergefilelist($diffmergeid) $fname]
     } elseif {[regexp {^@@ -([0-9]+),([0-9]+) \+([0-9]+),([0-9]+) @@(.*)} \
 		   $line match f1l f1c f2l f2c rest]} {
 	if {[info exists currentfile($ids)] && $currentfile($ids) >= 0} {
 	    # start of a new hunk
 	    if {$f1l == 0 && $f1c == 0} {
 		set f1l 1
 	    }
 	    if {$f2l == 0 && $f2c == 0} {
 		set f2l 1
 	    }
 	    set diffinhunk($ids) 1
 	    set diffoldstart($ids) $f1l
 	    set diffnewstart($ids) $f2l
 	    set diffoldlno($ids) $f1l
 	    set diffnewlno($ids) $f2l
 	    set difflcounts($ids) {}
 	    set noldlines($ids) 0
 	    set nnewlines($ids) 0
 	}
     }
 }
 
 proc processhunks {} {
     global diffmergeid parents nparents currenthunk
     global mergefilelist diffblocked mergefds
     global grouphunks grouplinestart grouplineend groupfilenum
 
     set nfiles [llength $mergefilelist($diffmergeid)]
     while 1 {
 	set fi $nfiles
 	set lno 0
 	# look for the earliest hunk
 	foreach p $parents($diffmergeid) {
 	    set ids [list $diffmergeid $p]
 	    if {![info exists currenthunk($ids)]} return
 	    set i [lindex $currenthunk($ids) 0]
 	    set l [lindex $currenthunk($ids) 2]
 	    if {$i < $fi || ($i == $fi && $l < $lno)} {
 		set fi $i
 		set lno $l
 		set pi $p
 	    }
 	}
 
 	if {$fi < $nfiles} {
 	    set ids [list $diffmergeid $pi]
 	    set hunk $currenthunk($ids)
 	    unset currenthunk($ids)
 	    if {$diffblocked($ids) > 0} {
 		fileevent $mergefds($ids) readable \
 		    [list getmergediffline $mergefds($ids) $ids $diffmergeid]
 	    }
 	    set diffblocked($ids) 0
 
 	    if {[info exists groupfilenum] && $groupfilenum == $fi
 		&& $lno <= $grouplineend} {
 		# add this hunk to the pending group
 		lappend grouphunks($pi) $hunk
 		set endln [lindex $hunk 4]
 		if {$endln > $grouplineend} {
 		    set grouplineend $endln
 		}
 		continue
 	    }
 	}
 
 	# succeeding stuff doesn't belong in this group, so
 	# process the group now
 	if {[info exists groupfilenum]} {
 	    processgroup
 	    unset groupfilenum
 	    unset grouphunks
 	}
 
 	if {$fi >= $nfiles} break
 
 	# start a new group
 	set groupfilenum $fi
 	set grouphunks($pi) [list $hunk]
 	set grouplinestart $lno
 	set grouplineend [lindex $hunk 4]
     }
 }
 
 proc processgroup {} {
     global groupfilelast groupfilenum difffilestart
     global mergefilelist diffmergeid ctext filelines
     global parents diffmergeid diffoffset
     global grouphunks grouplinestart grouplineend nparents
     global mergemax
 
     $ctext conf -state normal
     set id $diffmergeid
     set f $groupfilenum
     if {$groupfilelast != $f} {
 	$ctext insert end "\n"
 	set here [$ctext index "end - 1c"]
 	set difffilestart($f) $here
 	set mark fmark.[expr {$f + 1}]
 	$ctext mark set $mark $here
 	$ctext mark gravity $mark left
 	set header [lindex $mergefilelist($id) $f]
 	set l [expr {(78 - [string length $header]) / 2}]
 	set pad [string range "----------------------------------------" 1 $l]
 	$ctext insert end "$pad $header $pad\n" filesep
 	set groupfilelast $f
 	foreach p $parents($id) {
 	    set diffoffset($p) 0
 	}
     }
 
     $ctext insert end "@@" msep
     set nlines [expr {$grouplineend - $grouplinestart}]
     set events {}
     set pnum 0
     foreach p $parents($id) {
 	set startline [expr {$grouplinestart + $diffoffset($p)}]
 	set ol $startline
 	set nl $grouplinestart
 	if {[info exists grouphunks($p)]} {
 	    foreach h $grouphunks($p) {
 		set l [lindex $h 2]
 		if {$nl < $l} {
 		    for {} {$nl < $l} {incr nl} {
 			set filelines($p,$f,$ol) $filelines($id,$f,$nl)
 			incr ol
 		    }
 		}
 		foreach chunk [lindex $h 5] {
 		    if {[llength $chunk] == 2} {
 			set olc [lindex $chunk 0]
 			set nlc [lindex $chunk 1]
 			set nnl [expr {$nl + $nlc}]
 			lappend events [list $nl $nnl $pnum $olc $nlc]
 			incr ol $olc
 			set nl $nnl
 		    } else {
 			incr ol [lindex $chunk 0]
 			incr nl [lindex $chunk 0]
 		    }
 		}
 	    }
 	}
 	if {$nl < $grouplineend} {
 	    for {} {$nl < $grouplineend} {incr nl} {
 		set filelines($p,$f,$ol) $filelines($id,$f,$nl)
 		incr ol
 	    }
 	}
 	set nlines [expr {$ol - $startline}]
 	$ctext insert end " -$startline,$nlines" msep
 	incr pnum
     }
 
     set nlines [expr {$grouplineend - $grouplinestart}]
     $ctext insert end " +$grouplinestart,$nlines @@\n" msep
 
     set events [lsort -integer -index 0 $events]
     set nevents [llength $events]
     set nmerge $nparents($diffmergeid)
     set l $grouplinestart
     for {set i 0} {$i < $nevents} {set i $j} {
 	set nl [lindex $events $i 0]
 	while {$l < $nl} {
 	    $ctext insert end " $filelines($id,$f,$l)\n"
 	    incr l
 	}
 	set e [lindex $events $i]
 	set enl [lindex $e 1]
 	set j $i
 	set active {}
 	while 1 {
 	    set pnum [lindex $e 2]
 	    set olc [lindex $e 3]
 	    set nlc [lindex $e 4]
 	    if {![info exists delta($pnum)]} {
 		set delta($pnum) [expr {$olc - $nlc}]
 		lappend active $pnum
 	    } else {
 		incr delta($pnum) [expr {$olc - $nlc}]
 	    }
 	    if {[incr j] >= $nevents} break
 	    set e [lindex $events $j]
 	    if {[lindex $e 0] >= $enl} break
 	    if {[lindex $e 1] > $enl} {
 		set enl [lindex $e 1]
 	    }
 	}
 	set nlc [expr {$enl - $l}]
 	set ncol mresult
 	set bestpn -1
 	if {[llength $active] == $nmerge - 1} {
 	    # no diff for one of the parents, i.e. it's identical
 	    for {set pnum 0} {$pnum < $nmerge} {incr pnum} {
 		if {![info exists delta($pnum)]} {
 		    if {$pnum < $mergemax} {
 			lappend ncol m$pnum
 		    } else {
 			lappend ncol mmax
 		    }
 		    break
 		}
 	    }
 	} elseif {[llength $active] == $nmerge} {
 	    # all parents are different, see if one is very similar
 	    set bestsim 30
 	    for {set pnum 0} {$pnum < $nmerge} {incr pnum} {
 		set sim [similarity $pnum $l $nlc $f \
 			     [lrange $events $i [expr {$j-1}]]]
 		if {$sim > $bestsim} {
 		    set bestsim $sim
 		    set bestpn $pnum
 		}
 	    }
 	    if {$bestpn >= 0} {
 		lappend ncol m$bestpn
 	    }
 	}
 	set pnum -1
 	foreach p $parents($id) {
 	    incr pnum
 	    if {![info exists delta($pnum)] || $pnum == $bestpn} continue
 	    set olc [expr {$nlc + $delta($pnum)}]
 	    set ol [expr {$l + $diffoffset($p)}]
 	    incr diffoffset($p) $delta($pnum)
 	    unset delta($pnum)
 	    for {} {$olc > 0} {incr olc -1} {
 		$ctext insert end "-$filelines($p,$f,$ol)\n" m$pnum
 		incr ol
 	    }
 	}
 	set endl [expr {$l + $nlc}]
 	if {$bestpn >= 0} {
 	    # show this pretty much as a normal diff
 	    set p [lindex $parents($id) $bestpn]
 	    set ol [expr {$l + $diffoffset($p)}]
 	    incr diffoffset($p) $delta($bestpn)
 	    unset delta($bestpn)
 	    for {set k $i} {$k < $j} {incr k} {
 		set e [lindex $events $k]
 		if {[lindex $e 2] != $bestpn} continue
 		set nl [lindex $e 0]
 		set ol [expr {$ol + $nl - $l}]
 		for {} {$l < $nl} {incr l} {
 		    $ctext insert end "+$filelines($id,$f,$l)\n" $ncol
 		}
 		set c [lindex $e 3]
 		for {} {$c > 0} {incr c -1} {
 		    $ctext insert end "-$filelines($p,$f,$ol)\n" m$bestpn
 		    incr ol
 		}
 		set nl [lindex $e 1]
 		for {} {$l < $nl} {incr l} {
 		    $ctext insert end "+$filelines($id,$f,$l)\n" mresult
 		}
 	    }
 	}
 	for {} {$l < $endl} {incr l} {
 	    $ctext insert end "+$filelines($id,$f,$l)\n" $ncol
 	}
     }
     while {$l < $grouplineend} {
 	$ctext insert end " $filelines($id,$f,$l)\n"
 	incr l
     }
     $ctext conf -state disabled
 }
 
 proc similarity {pnum l nlc f events} {
     global diffmergeid parents diffoffset filelines
 
     set id $diffmergeid
     set p [lindex $parents($id) $pnum]
     set ol [expr {$l + $diffoffset($p)}]
     set endl [expr {$l + $nlc}]
     set same 0
     set diff 0
     foreach e $events {
 	if {[lindex $e 2] != $pnum} continue
 	set nl [lindex $e 0]
 	set ol [expr {$ol + $nl - $l}]
 	for {} {$l < $nl} {incr l} {
 	    incr same [string length $filelines($id,$f,$l)]
 	    incr same
 	}
 	set oc [lindex $e 3]
 	for {} {$oc > 0} {incr oc -1} {
 	    incr diff [string length $filelines($p,$f,$ol)]
 	    incr diff
 	    incr ol
 	}
 	set nl [lindex $e 1]
 	for {} {$l < $nl} {incr l} {
 	    incr diff [string length $filelines($id,$f,$l)]
 	    incr diff
 	}
     }
     for {} {$l < $endl} {incr l} {
 	incr same [string length $filelines($id,$f,$l)]
 	incr same
     }
     if {$same == 0} {
 	return 0
     }
     return [expr {200 * $same / (2 * $same + $diff)}]
 }
 
 proc startdiff {ids} {
     global treediffs diffids treepending diffmergeid
 
     set diffids $ids
     catch {unset diffmergeid}
     if {![info exists treediffs($ids)]} {
 	if {![info exists treepending]} {
 	    gettreediffs $ids
 	}
     } else {
 	addtocflist $ids
     }
 }
 
 proc addtocflist {ids} {
     global treediffs cflist
     foreach f $treediffs($ids) {
 	$cflist insert end $f
     }
     getblobdiffs $ids
 }
 
 proc gettreediffs {ids} {
     global treediff parents treepending
     set treepending $ids
     set treediff {}
     set id [lindex $ids 0]
     set p [lindex $ids 1]
     if [catch {set gdtf [open "|hg debug-diff-tree -r $p $id" r]}] return
     fconfigure $gdtf -blocking 0
     fileevent $gdtf readable [list gettreediffline $gdtf $ids]
 }
 
 proc gettreediffline {gdtf ids} {
     global treediff treediffs treepending diffids diffmergeid
 
     set n [gets $gdtf line]
     if {$n < 0} {
 	if {![eof $gdtf]} return
 	close $gdtf
 	set treediffs($ids) $treediff
 	unset treepending
 	if {$ids != $diffids} {
 	    gettreediffs $diffids
 	} else {
 	    if {[info exists diffmergeid]} {
 		contmergediff $ids
 	    } else {
 		addtocflist $ids
 	    }
 	}
 	return
     }
     set file [lindex $line 5]
     lappend treediff $file
 }
 
 proc getblobdiffs {ids} {
     global diffopts blobdifffd diffids env curdifftag curtagstart
     global difffilestart nextupdate diffinhdr treediffs
 
     set id [lindex $ids 0]
     set p [lindex $ids 1]
     set env(GIT_DIFF_OPTS) $diffopts
     set cmd [list | hg debug-diff-tree -r -p -C $p $id]
     if {[catch {set bdf [open $cmd r]} err]} {
 	puts "error getting diffs: $err"
 	return
     }
     set diffinhdr 0
     fconfigure $bdf -blocking 0
     set blobdifffd($ids) $bdf
     set curdifftag Comments
     set curtagstart 0.0
     catch {unset difffilestart}
     fileevent $bdf readable [list getblobdiffline $bdf $diffids]
     set nextupdate [expr {[clock clicks -milliseconds] + 100}]
 }
 
 proc getblobdiffline {bdf ids} {
     global diffids blobdifffd ctext curdifftag curtagstart
     global diffnexthead diffnextnote difffilestart
     global nextupdate diffinhdr treediffs
     global gaudydiff
 
     set n [gets $bdf line]
     if {$n < 0} {
 	if {[eof $bdf]} {
 	    close $bdf
 	    if {$ids == $diffids && $bdf == $blobdifffd($ids)} {
 		$ctext tag add $curdifftag $curtagstart end
 	    }
 	}
 	return
     }
     if {$ids != $diffids || $bdf != $blobdifffd($ids)} {
 	return
     }
     $ctext conf -state normal
     if {[regexp {^diff --git a/(.*) b/(.*)} $line match fname newname]} {
 	# start of a new file
 	$ctext insert end "\n"
 	$ctext tag add $curdifftag $curtagstart end
 	set curtagstart [$ctext index "end - 1c"]
 	set header $newname
 	set here [$ctext index "end - 1c"]
 	set i [lsearch -exact $treediffs($diffids) $fname]
 	if {$i >= 0} {
 	    set difffilestart($i) $here
 	    incr i
 	    $ctext mark set fmark.$i $here
 	    $ctext mark gravity fmark.$i left
 	}
 	if {$newname != $fname} {
 	    set i [lsearch -exact $treediffs($diffids) $newname]
 	    if {$i >= 0} {
 		set difffilestart($i) $here
 		incr i
 		$ctext mark set fmark.$i $here
 		$ctext mark gravity fmark.$i left
 	    }
 	}
 	set curdifftag "f:$fname"
 	$ctext tag delete $curdifftag
 	set l [expr {(78 - [string length $header]) / 2}]
 	set pad [string range "----------------------------------------" 1 $l]
 	$ctext insert end "$pad $header $pad\n" filesep
 	set diffinhdr 1
     } elseif {[regexp {^(---|\+\+\+)} $line]} {
 	set diffinhdr 0
     } elseif {[regexp {^@@ -([0-9]+),([0-9]+) \+([0-9]+),([0-9]+) @@(.*)} \
 		   $line match f1l f1c f2l f2c rest]} {
 	if {$gaudydiff} {
 	    $ctext insert end "\t" hunksep
 	    $ctext insert end "    $f1l    " d0 "    $f2l    " d1
 	    $ctext insert end "    $rest \n" hunksep
 	} else {
 	    $ctext insert end "$line\n" hunksep
 	}
 	set diffinhdr 0
     } else {
 	set x [string range $line 0 0]
 	if {$x == "-" || $x == "+"} {
 	    set tag [expr {$x == "+"}]
 	    if {$gaudydiff} {
 		set line [string range $line 1 end]
 	    }
 	    $ctext insert end "$line\n" d$tag
 	} elseif {$x == " "} {
 	    if {$gaudydiff} {
 		set line [string range $line 1 end]
 	    }
 	    $ctext insert end "$line\n"
 	} elseif {$diffinhdr || $x == "\\"} {
 	    # e.g. "\ No newline at end of file"
 	    $ctext insert end "$line\n" filesep
 	} else {
 	    # Something else we don't recognize
 	    if {$curdifftag != "Comments"} {
 		$ctext insert end "\n"
 		$ctext tag add $curdifftag $curtagstart end
 		set curtagstart [$ctext index "end - 1c"]
 		set curdifftag Comments
 	    }
 	    $ctext insert end "$line\n" filesep
 	}
     }
     $ctext conf -state disabled
     if {[clock clicks -milliseconds] >= $nextupdate} {
 	incr nextupdate 100
 	fileevent $bdf readable {}
 	update
 	fileevent $bdf readable "getblobdiffline $bdf {$ids}"
     }
 }
 
 proc nextfile {} {
     global difffilestart ctext
     set here [$ctext index @0,0]
     for {set i 0} {[info exists difffilestart($i)]} {incr i} {
 	if {[$ctext compare $difffilestart($i) > $here]} {
 	    if {![info exists pos]
 		|| [$ctext compare $difffilestart($i) < $pos]} {
 		set pos $difffilestart($i)
 	    }
 	}
     }
     if {[info exists pos]} {
 	$ctext yview $pos
     }
 }
 
 proc listboxsel {} {
     global ctext cflist currentid
     if {![info exists currentid]} return
     set sel [lsort [$cflist curselection]]
     if {$sel eq {}} return
     set first [lindex $sel 0]
     catch {$ctext yview fmark.$first}
 }
 
 proc setcoords {} {
     global linespc charspc canvx0 canvy0 mainfont
     global xspc1 xspc2 lthickness
 
     set linespc [font metrics $mainfont -linespace]
     set charspc [font measure $mainfont "m"]
     set canvy0 [expr 3 + 0.5 * $linespc]
     set canvx0 [expr 3 + 0.5 * $linespc]
     set lthickness [expr {int($linespc / 9) + 1}]
     set xspc1(0) $linespc
     set xspc2 $linespc
 }
 
 proc redisplay {} {
     global stopped redisplaying phase
     if {$stopped > 1} return
     if {$phase == "getcommits"} return
     set redisplaying 1
     if {$phase == "drawgraph" || $phase == "incrdraw"} {
 	set stopped 1
     } else {
 	drawgraph
     }
 }
 
 proc incrfont {inc} {
     global mainfont namefont textfont ctext canv phase
     global stopped entries
     unmarkmatches
     set mainfont [lreplace $mainfont 1 1 [expr {[lindex $mainfont 1] + $inc}]]
     set namefont [lreplace $namefont 1 1 [expr {[lindex $namefont 1] + $inc}]]
     set textfont [lreplace $textfont 1 1 [expr {[lindex $textfont 1] + $inc}]]
     setcoords
     $ctext conf -font $textfont
     $ctext tag conf filesep -font [concat $textfont bold]
     foreach e $entries {
 	$e conf -font $mainfont
     }
     if {$phase == "getcommits"} {
 	$canv itemconf textitems -font $mainfont
     }
     redisplay
 }
 
 proc clearsha1 {} {
     global sha1entry sha1string
     if {[string length $sha1string] == 40} {
 	$sha1entry delete 0 end
     }
 }
 
 proc sha1change {n1 n2 op} {
     global sha1string currentid sha1but
     if {$sha1string == {}
 	|| ([info exists currentid] && $sha1string == $currentid)} {
 	set state disabled
     } else {
 	set state normal
     }
     if {[$sha1but cget -state] == $state} return
     if {$state == "normal"} {
 	$sha1but conf -state normal -relief raised -text "Goto: "
     } else {
 	$sha1but conf -state disabled -relief flat -text "SHA1 ID: "
     }
 }
 
 proc gotocommit {} {
     global sha1string currentid idline tagids
     global lineid numcommits
 
     if {$sha1string == {}
 	|| ([info exists currentid] && $sha1string == $currentid)} return
     if {[info exists tagids($sha1string)]} {
 	set id $tagids($sha1string)
     } else {
 	set id [string tolower $sha1string]
 	if {[regexp {^[0-9a-f]{4,39}$} $id]} {
 	    set matches {}
 	    for {set l 0} {$l < $numcommits} {incr l} {
 		if {[string match $id* $lineid($l)]} {
 		    lappend matches $lineid($l)
 		}
 	    }
 	    if {$matches ne {}} {
 		if {[llength $matches] > 1} {
 		    error_popup "Short SHA1 id $id is ambiguous"
 		    return
 		}
 		set id [lindex $matches 0]
 	    }
 	}
     }
     if {[info exists idline($id)]} {
 	selectline $idline($id) 1
 	return
     }
     if {[regexp {^[0-9a-fA-F]{4,}$} $sha1string]} {
 	set type "SHA1 id"
     } else {
 	set type "Tag"
     }
     error_popup "$type $sha1string is not known"
 }
 
 proc lineenter {x y id} {
     global hoverx hovery hoverid hovertimer
     global commitinfo canv
 
     if {![info exists commitinfo($id)]} return
     set hoverx $x
     set hovery $y
     set hoverid $id
     if {[info exists hovertimer]} {
 	after cancel $hovertimer
     }
     set hovertimer [after 500 linehover]
     $canv delete hover
 }
 
 proc linemotion {x y id} {
     global hoverx hovery hoverid hovertimer
 
     if {[info exists hoverid] && $id == $hoverid} {
 	set hoverx $x
 	set hovery $y
 	if {[info exists hovertimer]} {
 	    after cancel $hovertimer
 	}
 	set hovertimer [after 500 linehover]
     }
 }
 
 proc lineleave {id} {
     global hoverid hovertimer canv
 
     if {[info exists hoverid] && $id == $hoverid} {
 	$canv delete hover
 	if {[info exists hovertimer]} {
 	    after cancel $hovertimer
 	    unset hovertimer
 	}
 	unset hoverid
     }
 }
 
 proc linehover {} {
     global hoverx hovery hoverid hovertimer
     global canv linespc lthickness
     global commitinfo mainfont
 
     set text [lindex $commitinfo($hoverid) 0]
     set ymax [lindex [$canv cget -scrollregion] 3]
     if {$ymax == {}} return
     set yfrac [lindex [$canv yview] 0]
     set x [expr {$hoverx + 2 * $linespc}]
     set y [expr {$hovery + $yfrac * $ymax - $linespc / 2}]
     set x0 [expr {$x - 2 * $lthickness}]
     set y0 [expr {$y - 2 * $lthickness}]
     set x1 [expr {$x + [font measure $mainfont $text] + 2 * $lthickness}]
     set y1 [expr {$y + $linespc + 2 * $lthickness}]
     set t [$canv create rectangle $x0 $y0 $x1 $y1 \
 	       -fill \#ffff80 -outline black -width 1 -tags hover]
     $canv raise $t
     set t [$canv create text $x $y -anchor nw -text $text -tags hover]
     $canv raise $t
 }
 
 proc clickisonarrow {id y} {
     global mainline mainlinearrow sidelines lthickness
 
     set thresh [expr {2 * $lthickness + 6}]
     if {[info exists mainline($id)]} {
 	if {$mainlinearrow($id) ne "none"} {
 	    if {abs([lindex $mainline($id) 1] - $y) < $thresh} {
 		return "up"
 	    }
 	}
     }
     if {[info exists sidelines($id)]} {
 	foreach ls $sidelines($id) {
 	    set coords [lindex $ls 0]
 	    set arrow [lindex $ls 2]
 	    if {$arrow eq "first" || $arrow eq "both"} {
 		if {abs([lindex $coords 1] - $y) < $thresh} {
 		    return "up"
 		}
 	    }
 	    if {$arrow eq "last" || $arrow eq "both"} {
 		if {abs([lindex $coords end] - $y) < $thresh} {
 		    return "down"
 		}
 	    }
 	}
     }
     return {}
 }
 
 proc arrowjump {id dirn y} {
     global mainline sidelines canv
 
     set yt {}
     if {$dirn eq "down"} {
 	if {[info exists mainline($id)]} {
 	    set y1 [lindex $mainline($id) 1]
 	    if {$y1 > $y} {
 		set yt $y1
 	    }
 	}
 	if {[info exists sidelines($id)]} {
 	    foreach ls $sidelines($id) {
 		set y1 [lindex $ls 0 1]
 		if {$y1 > $y && ($yt eq {} || $y1 < $yt)} {
 		    set yt $y1
 		}
 	    }
 	}
     } else {
 	if {[info exists sidelines($id)]} {
 	    foreach ls $sidelines($id) {
 		set y1 [lindex $ls 0 end]
 		if {$y1 < $y && ($yt eq {} || $y1 > $yt)} {
 		    set yt $y1
 		}
 	    }
 	}
     }
     if {$yt eq {}} return
     set ymax [lindex [$canv cget -scrollregion] 3]
     if {$ymax eq {} || $ymax <= 0} return
     set view [$canv yview]
     set yspan [expr {[lindex $view 1] - [lindex $view 0]}]
     set yfrac [expr {$yt / $ymax - $yspan / 2}]
     if {$yfrac < 0} {
 	set yfrac 0
     }
     $canv yview moveto $yfrac
 }
 
 proc lineclick {x y id isnew} {
     global ctext commitinfo children cflist canv thickerline
 
     unmarkmatches
     unselectline
     normalline
     $canv delete hover
     # draw this line thicker than normal
     drawlines $id 1
     set thickerline $id
     if {$isnew} {
 	set ymax [lindex [$canv cget -scrollregion] 3]
 	if {$ymax eq {}} return
 	set yfrac [lindex [$canv yview] 0]
 	set y [expr {$y + $yfrac * $ymax}]
     }
     set dirn [clickisonarrow $id $y]
     if {$dirn ne {}} {
 	arrowjump $id $dirn $y
 	return
     }
 
     if {$isnew} {
 	addtohistory [list lineclick $x $y $id 0]
     }
     # fill the details pane with info about this line
     $ctext conf -state normal
     $ctext delete 0.0 end
     $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 }
     $ctext insert end "Parent:\t"
     $ctext insert end $id [list link link0]
     $ctext tag bind link0 <1> [list selbyid $id]
     set info $commitinfo($id)
     $ctext insert end "\n\t[lindex $info 0]\n"
     $ctext insert end "\tAuthor:\t[lindex $info 1]\n"
     $ctext insert end "\tDate:\t[lindex $info 2]\n"
     if {[info exists children($id)]} {
 	$ctext insert end "\nChildren:"
 	set i 0
 	foreach child $children($id) {
 	    incr i
 	    set info $commitinfo($child)
 	    $ctext insert end "\n\t"
 	    $ctext insert end $child [list link link$i]
 	    $ctext tag bind link$i <1> [list selbyid $child]
 	    $ctext insert end "\n\t[lindex $info 0]"
 	    $ctext insert end "\n\tAuthor:\t[lindex $info 1]"
 	    $ctext insert end "\n\tDate:\t[lindex $info 2]\n"
 	}
     }
     $ctext conf -state disabled
 
     $cflist delete 0 end
 }
 
 proc normalline {} {
     global thickerline
     if {[info exists thickerline]} {
 	drawlines $thickerline 0
 	unset thickerline
     }
 }
 
 proc selbyid {id} {
     global idline
     if {[info exists idline($id)]} {
 	selectline $idline($id) 1
     }
 }
 
 proc mstime {} {
     global startmstime
     if {![info exists startmstime]} {
 	set startmstime [clock clicks -milliseconds]
     }
     return [format "%.3f" [expr {([clock click -milliseconds] - $startmstime) / 1000.0}]]
 }
 
 proc rowmenu {x y id} {
     global rowctxmenu idline selectedline rowmenuid
 
     if {![info exists selectedline] || $idline($id) eq $selectedline} {
 	set state disabled
     } else {
 	set state normal
     }
     $rowctxmenu entryconfigure 0 -state $state
     $rowctxmenu entryconfigure 1 -state $state
     $rowctxmenu entryconfigure 2 -state $state
     set rowmenuid $id
     tk_popup $rowctxmenu $x $y
 }
 
 proc diffvssel {dirn} {
     global rowmenuid selectedline lineid
 
     if {![info exists selectedline]} return
     if {$dirn} {
 	set oldid $lineid($selectedline)
 	set newid $rowmenuid
     } else {
 	set oldid $rowmenuid
 	set newid $lineid($selectedline)
     }
     addtohistory [list doseldiff $oldid $newid]
     doseldiff $oldid $newid
 }
 
 proc doseldiff {oldid newid} {
     global ctext cflist
     global commitinfo
 
     $ctext conf -state normal
     $ctext delete 0.0 end
     $ctext mark set fmark.0 0.0
     $ctext mark gravity fmark.0 left
     $cflist delete 0 end
     $cflist insert end "Top"
     $ctext insert end "From "
     $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 }
     $ctext tag bind link0 <1> [list selbyid $oldid]
     $ctext insert end $oldid [list link link0]
     $ctext insert end "\n     "
     $ctext insert end [lindex $commitinfo($oldid) 0]
     $ctext insert end "\n\nTo   "
     $ctext tag bind link1 <1> [list selbyid $newid]
     $ctext insert end $newid [list link link1]
     $ctext insert end "\n     "
     $ctext insert end [lindex $commitinfo($newid) 0]
     $ctext insert end "\n"
     $ctext conf -state disabled
     $ctext tag delete Comments
     $ctext tag remove found 1.0 end
     startdiff [list $newid $oldid]
 }
 
 proc mkpatch {} {
     global rowmenuid currentid commitinfo patchtop patchnum
 
     if {![info exists currentid]} return
     set oldid $currentid
     set oldhead [lindex $commitinfo($oldid) 0]
     set newid $rowmenuid
     set newhead [lindex $commitinfo($newid) 0]
     set top .patch
     set patchtop $top
     catch {destroy $top}
     toplevel $top
     label $top.title -text "Generate patch"
     grid $top.title - -pady 10
     label $top.from -text "From:"
     entry $top.fromsha1 -width 40 -relief flat
     $top.fromsha1 insert 0 $oldid
     $top.fromsha1 conf -state readonly
     grid $top.from $top.fromsha1 -sticky w
     entry $top.fromhead -width 60 -relief flat
     $top.fromhead insert 0 $oldhead
     $top.fromhead conf -state readonly
     grid x $top.fromhead -sticky w
     label $top.to -text "To:"
     entry $top.tosha1 -width 40 -relief flat
     $top.tosha1 insert 0 $newid
     $top.tosha1 conf -state readonly
     grid $top.to $top.tosha1 -sticky w
     entry $top.tohead -width 60 -relief flat
     $top.tohead insert 0 $newhead
     $top.tohead conf -state readonly
     grid x $top.tohead -sticky w
     button $top.rev -text "Reverse" -command mkpatchrev -padx 5
     grid $top.rev x -pady 10
     label $top.flab -text "Output file:"
     entry $top.fname -width 60
     $top.fname insert 0 [file normalize "patch$patchnum.patch"]
     incr patchnum
     grid $top.flab $top.fname -sticky w
     frame $top.buts
     button $top.buts.gen -text "Generate" -command mkpatchgo
     button $top.buts.can -text "Cancel" -command mkpatchcan
     grid $top.buts.gen $top.buts.can
     grid columnconfigure $top.buts 0 -weight 1 -uniform a
     grid columnconfigure $top.buts 1 -weight 1 -uniform a
     grid $top.buts - -pady 10 -sticky ew
     focus $top.fname
 }
 
 proc mkpatchrev {} {
     global patchtop
 
     set oldid [$patchtop.fromsha1 get]
     set oldhead [$patchtop.fromhead get]
     set newid [$patchtop.tosha1 get]
     set newhead [$patchtop.tohead get]
     foreach e [list fromsha1 fromhead tosha1 tohead] \
 	    v [list $newid $newhead $oldid $oldhead] {
 	$patchtop.$e conf -state normal
 	$patchtop.$e delete 0 end
 	$patchtop.$e insert 0 $v
 	$patchtop.$e conf -state readonly
     }
 }
 
 proc mkpatchgo {} {
     global patchtop
 
     set oldid [$patchtop.fromsha1 get]
     set newid [$patchtop.tosha1 get]
     set fname [$patchtop.fname get]
     if {[catch {exec hg debug-diff-tree -p $oldid $newid >$fname &} err]} {
 	error_popup "Error creating patch: $err"
     }
     catch {destroy $patchtop}
     unset patchtop
 }
 
 proc mkpatchcan {} {
     global patchtop
 
     catch {destroy $patchtop}
     unset patchtop
 }
 
 proc mktag {} {
     global rowmenuid mktagtop commitinfo
 
     set top .maketag
     set mktagtop $top
     catch {destroy $top}
     toplevel $top
     label $top.title -text "Create tag"
     grid $top.title - -pady 10
     label $top.id -text "ID:"
     entry $top.sha1 -width 40 -relief flat
     $top.sha1 insert 0 $rowmenuid
     $top.sha1 conf -state readonly
     grid $top.id $top.sha1 -sticky w
     entry $top.head -width 60 -relief flat
     $top.head insert 0 [lindex $commitinfo($rowmenuid) 0]
     $top.head conf -state readonly
     grid x $top.head -sticky w
     label $top.tlab -text "Tag name:"
     entry $top.tag -width 60
     grid $top.tlab $top.tag -sticky w
     frame $top.buts
     button $top.buts.gen -text "Create" -command mktaggo
     button $top.buts.can -text "Cancel" -command mktagcan
     grid $top.buts.gen $top.buts.can
     grid columnconfigure $top.buts 0 -weight 1 -uniform a
     grid columnconfigure $top.buts 1 -weight 1 -uniform a
     grid $top.buts - -pady 10 -sticky ew
     focus $top.tag
 }
 
 proc domktag {} {
     global mktagtop env tagids idtags
 
     set id [$mktagtop.sha1 get]
     set tag [$mktagtop.tag get]
     if {$tag == {}} {
 	error_popup "No tag name specified"
 	return
     }
     if {[info exists tagids($tag)]} {
 	error_popup "Tag \"$tag\" already exists"
 	return
     }
     if {[catch {
 	set out [exec hg tag $tag $id]
     } err]} {
 	error_popup "Error creating tag: $err"
 	return
     }
 
     set tagids($tag) $id
     lappend idtags($id) $tag
     redrawtags $id
 }
 
 proc redrawtags {id} {
     global canv linehtag idline idpos selectedline
 
     if {![info exists idline($id)]} return
     $canv delete tag.$id
     set xt [eval drawtags $id $idpos($id)]
     $canv coords $linehtag($idline($id)) $xt [lindex $idpos($id) 2]
     if {[info exists selectedline] && $selectedline == $idline($id)} {
 	selectline $selectedline 0
     }
 }
 
 proc mktagcan {} {
     global mktagtop
 
     catch {destroy $mktagtop}
     unset mktagtop
 }
 
 proc mktaggo {} {
     domktag
     mktagcan
 }
 
 proc writecommit {} {
     global rowmenuid wrcomtop commitinfo wrcomcmd
 
     set top .writecommit
     set wrcomtop $top
     catch {destroy $top}
     toplevel $top
     label $top.title -text "Write commit to file"
     grid $top.title - -pady 10
     label $top.id -text "ID:"
     entry $top.sha1 -width 40 -relief flat
     $top.sha1 insert 0 $rowmenuid
     $top.sha1 conf -state readonly
     grid $top.id $top.sha1 -sticky w
     entry $top.head -width 60 -relief flat
     $top.head insert 0 [lindex $commitinfo($rowmenuid) 0]
     $top.head conf -state readonly
     grid x $top.head -sticky w
     label $top.clab -text "Command:"
     entry $top.cmd -width 60 -textvariable wrcomcmd
     grid $top.clab $top.cmd -sticky w -pady 10
     label $top.flab -text "Output file:"
     entry $top.fname -width 60
     $top.fname insert 0 [file normalize "commit-[string range $rowmenuid 0 6]"]
     grid $top.flab $top.fname -sticky w
     frame $top.buts
     button $top.buts.gen -text "Write" -command wrcomgo
     button $top.buts.can -text "Cancel" -command wrcomcan
     grid $top.buts.gen $top.buts.can
     grid columnconfigure $top.buts 0 -weight 1 -uniform a
     grid columnconfigure $top.buts 1 -weight 1 -uniform a
     grid $top.buts - -pady 10 -sticky ew
     focus $top.fname
 }
 
 proc wrcomgo {} {
     global wrcomtop
 
     set id [$wrcomtop.sha1 get]
     set cmd "echo $id | [$wrcomtop.cmd get]"
     set fname [$wrcomtop.fname get]
     if {[catch {exec sh -c $cmd >$fname &} err]} {
 	error_popup "Error writing commit: $err"
     }
     catch {destroy $wrcomtop}
     unset wrcomtop
 }
 
 proc wrcomcan {} {
     global wrcomtop
 
     catch {destroy $wrcomtop}
     unset wrcomtop
 }
 
 proc listrefs {id} {
     global idtags idheads idotherrefs
 
     set x {}
     if {[info exists idtags($id)]} {
 	set x $idtags($id)
     }
     set y {}
     if {[info exists idheads($id)]} {
 	set y $idheads($id)
     }
     set z {}
     if {[info exists idotherrefs($id)]} {
 	set z $idotherrefs($id)
     }
     return [list $x $y $z]
 }
 
 proc rereadrefs {} {
     global idtags idheads idotherrefs
     global tagids headids otherrefids
 
     set refids [concat [array names idtags] \
 		    [array names idheads] [array names idotherrefs]]
     foreach id $refids {
 	if {![info exists ref($id)]} {
 	    set ref($id) [listrefs $id]
 	}
     }
     foreach v {tagids idtags headids idheads otherrefids idotherrefs} {
 	catch {unset $v}
     }
     readrefs
     set refids [lsort -unique [concat $refids [array names idtags] \
 			[array names idheads] [array names idotherrefs]]]
     foreach id $refids {
 	set v [listrefs $id]
 	if {![info exists ref($id)] || $ref($id) != $v} {
 	    redrawtags $id
 	}
     }
 }
 
 proc showtag {tag isnew} {
     global ctext cflist tagcontents tagids linknum
 
     if {$isnew} {
 	addtohistory [list showtag $tag 0]
     }
     $ctext conf -state normal
     $ctext delete 0.0 end
     set linknum 0
     if {[info exists tagcontents($tag)]} {
 	set text $tagcontents($tag)
     } else {
 	set text "Tag: $tag\nId:  $tagids($tag)"
     }
     appendwithlinks $text
     $ctext conf -state disabled
     $cflist delete 0 end
 }
 
 proc doquit {} {
     global stopped
     set stopped 100
     destroy .
 }
 
 # defaults...
 set datemode 0
 set boldnames 0
 set diffopts "-U 5 -p"
 set wrcomcmd "hg debug-diff-tree --stdin -p --pretty"
 
 set mainfont {Helvetica 9}
 set textfont {Courier 9}
 set findmergefiles 0
 set gaudydiff 0
 set maxgraphpct 50
 set maxwidth 16
 
 set colors {green red blue magenta darkgrey brown orange}
 
 catch {source ~/.gitk}
 
 set namefont $mainfont
 if {$boldnames} {
     lappend namefont bold
 }
 
 set revtreeargs {}
 foreach arg $argv {
     switch -regexp -- $arg {
 	"^$" { }
 	"^-b" { set boldnames 1 }
 	"^-d" { set datemode 1 }
 	default {
 	    lappend revtreeargs $arg
 	}
     }
 }
 
 set history {}
 set historyindex 0
 
 set stopped 0
 set redisplaying 0
 set stuffsaved 0
 set patchnum 0
 setcoords
 makewindow
 readrefs
 getcommits $revtreeargs