# git-gui Git repository chooser
# Copyright (C) 2007 Shawn Pearce

class choose_repository {

field top
field w
field w_body      ; # Widget holding the center content
field w_next      ; # Next button
field w_quit      ; # Quit button
field o_cons      ; # Console object (if active)
field w_types     ; # List of type buttons in clone
field w_recentlist ; # Listbox containing recent repositories
field w_localpath  ; # Entry widget bound to local_path

field done              0 ; # Finished picking the repository?
field local_path       {} ; # Where this repository is locally
field origin_url       {} ; # Where we are cloning from
field origin_name  origin ; # What we shall call 'origin'
field clone_type hardlink ; # Type of clone to construct
field readtree_err        ; # Error output from read-tree (if any)
field sorted_recent       ; # recent repositories (sorted)

constructor pick {} {
        global M1T M1B use_ttk NS

        if {[set maxrecent [get_config gui.maxrecentrepo]] eq {}} {
                set maxrecent 10
        }

        make_dialog top w
        wm title $top [mc "Git Gui"]

        if {$top eq {.}} {
                menu $w.mbar -tearoff 0
                $top configure -menu $w.mbar

                set m_repo $w.mbar.repository
                $w.mbar add cascade \
                        -label [mc Repository] \
                        -menu $m_repo
                menu $m_repo

                if {[is_MacOSX]} {
                        $w.mbar add cascade -label Apple -menu .mbar.apple
                        menu $w.mbar.apple
                        $w.mbar.apple add command \
                                -label [mc "About %s" [appname]] \
                                -command do_about
                        $w.mbar.apple add command \
                                -label [mc "Show SSH Key"] \
                                -command do_ssh_key
                } else {
                        $w.mbar add cascade -label [mc Help] -menu $w.mbar.help
                        menu $w.mbar.help
                        $w.mbar.help add command \
                                -label [mc "About %s" [appname]] \
                                -command do_about
                        $w.mbar.help add command \
                                -label [mc "Show SSH Key"] \
                                -command do_ssh_key
                }

                wm protocol $top WM_DELETE_WINDOW exit
                bind $top <$M1B-q> exit
                bind $top <$M1B-Q> exit
                bind $top <Key-Escape> exit
        } else {
                wm geometry $top "+[winfo rootx .]+[winfo rooty .]"
                bind $top <Key-Escape> [list destroy $top]
                set m_repo {}
        }

        pack [git_logo $w.git_logo] -side left -fill y -padx 10 -pady 10

        set w_body $w.body
        set opts $w_body.options
        ${NS}::frame $w_body
        text $opts \
                -cursor $::cursor_ptr \
                -relief flat \
                -background [get_bg_color $w_body] \
                -wrap none \
                -spacing1 5 \
                -width 50 \
                -height 3
        pack $opts -anchor w -fill x

        $opts tag conf link_new -foreground blue -underline 1
        $opts tag bind link_new <1> [cb _next new]
        $opts insert end [mc "Create New Repository"] link_new
        $opts insert end "\n"
        if {$m_repo ne {}} {
                $m_repo add command \
                        -command [cb _next new] \
                        -accelerator $M1T-N \
                        -label [mc "New..."]
                bind $top <$M1B-n> [cb _next new]
                bind $top <$M1B-N> [cb _next new]
        }

        $opts tag conf link_clone -foreground blue -underline 1
        $opts tag bind link_clone <1> [cb _next clone]
        $opts insert end [mc "Clone Existing Repository"] link_clone
        $opts insert end "\n"
        if {$m_repo ne {}} {
                if {[tk windowingsystem] eq "win32"} {
                        set key L
                } else {
                        set key C
                }
                $m_repo add command \
                        -command [cb _next clone] \
                        -accelerator $M1T-$key \
                        -label [mc "Clone..."]
                bind $top <$M1B-[string tolower $key]> [cb _next clone]
                bind $top <$M1B-[string toupper $key]> [cb _next clone]
        }

        $opts tag conf link_open -foreground blue -underline 1
        $opts tag bind link_open <1> [cb _next open]
        $opts insert end [mc "Open Existing Repository"] link_open
        $opts insert end "\n"
        if {$m_repo ne {}} {
                $m_repo add command \
                        -command [cb _next open] \
                        -accelerator $M1T-O \
                        -label [mc "Open..."]
                bind $top <$M1B-o> [cb _next open]
                bind $top <$M1B-O> [cb _next open]
        }

        $opts conf -state disabled

        set sorted_recent [_get_recentrepos]
        if {[llength $sorted_recent] > 0} {
                if {$m_repo ne {}} {
                        $m_repo add separator
                        $m_repo add command \
                                -state disabled \
                                -label [mc "Recent Repositories"]
                }

                ${NS}::label $w_body.space
                ${NS}::label $w_body.recentlabel \
                        -anchor w \
                        -text [mc "Open Recent Repository:"]
                set w_recentlist $w_body.recentlist
                text $w_recentlist \
                        -cursor $::cursor_ptr \
                        -relief flat \
                        -background [get_bg_color $w_body.recentlabel] \
                        -wrap none \
                        -width 50 \
                        -height $maxrecent
                $w_recentlist tag conf link \
                        -foreground blue \
                        -underline 1
                set home $::env(HOME)
                if {[is_Cygwin]} {
                        set home [exec cygpath --windows --absolute $home]
                }
                set home "[file normalize $home]/"
                set hlen [string length $home]
                foreach p $sorted_recent {
                        set path $p
                        if {[string equal -length $hlen $home $p]} {
                                set p "~/[string range $p $hlen end]"
                        }
                        regsub -all "\n" $p "\\n" p
                        $w_recentlist insert end $p link
                        $w_recentlist insert end "\n"

                        if {$m_repo ne {}} {
                                $m_repo add command \
                                        -command [cb _open_recent_path $path] \
                                        -label "    $p"
                        }
                }
                $w_recentlist conf -state disabled
                $w_recentlist tag bind link <1> [cb _open_recent %x,%y]
                pack $w_body.space -anchor w -fill x
                pack $w_body.recentlabel -anchor w -fill x
                pack $w_recentlist -anchor w -fill x
        }
        pack $w_body -fill x -padx 10 -pady 10

        ${NS}::frame $w.buttons
        set w_next $w.buttons.next
        set w_quit $w.buttons.quit
        ${NS}::button $w_quit \
                -text [mc "Quit"] \
                -command exit
        pack $w_quit -side right -padx 5
        pack $w.buttons -side bottom -fill x -padx 10 -pady 10

        if {$m_repo ne {}} {
                $m_repo add separator
                $m_repo add command \
                        -label [mc Quit] \
                        -command exit \
                        -accelerator $M1T-Q
        }

        bind $top <Return> [cb _invoke_next]
        bind $top <Visibility> "
                [cb _center]
                grab $top
                focus $top
                bind $top <Visibility> {}
        "
        wm deiconify $top
        tkwait variable @done

        grab release $top
        if {$top eq {.}} {
                eval destroy [winfo children $top]
        }
}

method _center {} {
        set nx [winfo reqwidth $top]
        set ny [winfo reqheight $top]
        set rx [expr {([winfo screenwidth  $top] - $nx) / 3}]
        set ry [expr {([winfo screenheight $top] - $ny) / 3}]
        wm geometry $top [format {+%d+%d} $rx $ry]
}

method _invoke_next {} {
        if {[winfo exists $w_next]} {
                uplevel #0 [$w_next cget -command]
        }
}

proc _get_recentrepos {} {
        set recent [list]
        foreach p [get_config gui.recentrepo] {
                if {[_is_git [file join $p .git]]} {
                        lappend recent $p
                } else {
                        _unset_recentrepo $p
                }
        }
        return [lsort $recent]
}

proc _unset_recentrepo {p} {
        regsub -all -- {([()\[\]{}\.^$+*?\\])} $p {\\\1} p
        git config --global --unset gui.recentrepo "^$p\$"
        load_config 1
}

proc _append_recentrepos {path} {
        set path [file normalize $path]
        set recent [get_config gui.recentrepo]

        if {[lindex $recent end] eq $path} {
                return
        }

        set i [lsearch $recent $path]
        if {$i >= 0} {
                _unset_recentrepo $path
                set recent [lreplace $recent $i $i]
        }

        lappend recent $path
        git config --global --add gui.recentrepo $path
        load_config 1

        if {[set maxrecent [get_config gui.maxrecentrepo]] eq {}} {
                set maxrecent 10
        }

        while {[llength $recent] > $maxrecent} {
                _unset_recentrepo [lindex $recent 0]
                set recent [lrange $recent 1 end]
        }
}

method _open_recent {xy} {
        set id [lindex [split [$w_recentlist index @$xy] .] 0]
        set local_path [lindex $sorted_recent [expr {$id - 1}]]
        _do_open2 $this
}

method _open_recent_path {p} {
        set local_path $p
        _do_open2 $this
}

method _next {action} {
        global NS
        destroy $w_body
        if {![winfo exists $w_next]} {
                ${NS}::button $w_next -default active
                set pos -before
                if {[tk windowingsystem] eq "win32"} { set pos -after }
                pack $w_next -side right -padx 5 $pos $w_quit
        }
        _do_$action $this
}

method _write_local_path {args} {
        if {$local_path eq {}} {
                $w_next conf -state disabled
        } else {
                $w_next conf -state normal
        }
}

method _git_init {} {
        if {[catch {file mkdir $local_path} err]} {
                error_popup [strcat \
                        [mc "Failed to create repository %s:" $local_path] \
                        "\n\n$err"]
                return 0
        }

        if {[catch {cd $local_path} err]} {
                error_popup [strcat \
                        [mc "Failed to create repository %s:" $local_path] \
                        "\n\n$err"]
                return 0
        }

        if {[catch {git init} err]} {
                error_popup [strcat \
                        [mc "Failed to create repository %s:" $local_path] \
                        "\n\n$err"]
                return 0
        }

        _append_recentrepos [pwd]
        set ::_gitdir .git
        set ::_prefix {}
        return 1
}

proc _is_git {path} {
        if {[file exists [file join $path HEAD]]
         && [file exists [file join $path objects]]
         && [file exists [file join $path config]]} {
                return 1
        }
        if {[is_Cygwin]} {
                if {[file exists [file join $path HEAD]]
                 && [file exists [file join $path objects.lnk]]
                 && [file exists [file join $path config.lnk]]} {
                        return 1
                }
        }
        return 0
}

proc _objdir {path} {
        set objdir [file join $path .git objects]
        if {[file isdirectory $objdir]} {
                return $objdir
        }

        set objdir [file join $path objects]
        if {[file isdirectory $objdir]} {
                return $objdir
        }

        if {[is_Cygwin]} {
                set objdir [file join $path .git objects.lnk]
                if {[file isfile $objdir]} {
                        return [win32_read_lnk $objdir]
                }

                set objdir [file join $path objects.lnk]
                if {[file isfile $objdir]} {
                        return [win32_read_lnk $objdir]
                }
        }

        return {}
}

######################################################################
##
## Create New Repository

method _do_new {} {
        global use_ttk NS
        $w_next conf \
                -state disabled \
                -command [cb _do_new2] \
                -text [mc "Create"]

        ${NS}::frame $w_body
        ${NS}::label $w_body.h \
                -font font_uibold -anchor center \
                -text [mc "Create New Repository"]
        pack $w_body.h -side top -fill x -pady 10
        pack $w_body -fill x -padx 10

        ${NS}::frame $w_body.where
        ${NS}::label $w_body.where.l -text [mc "Directory:"]
        ${NS}::entry $w_body.where.t \
                -textvariable @local_path \
                -width 50
        ${NS}::button $w_body.where.b \
                -text [mc "Browse"] \
                -command [cb _new_local_path]
        set w_localpath $w_body.where.t

        grid $w_body.where.l $w_body.where.t $w_body.where.b -sticky ew
        pack $w_body.where -fill x

        grid columnconfigure $w_body.where 1 -weight 1

        trace add variable @local_path write [cb _write_local_path]
        bind $w_body.h <Destroy> [list trace remove variable @local_path write [cb _write_local_path]]
        update
        focus $w_body.where.t
}

method _new_local_path {} {
        if {$local_path ne {}} {
                set p [file dirname $local_path]
        } else {
                set p [pwd]
        }

        set p [tk_chooseDirectory \
                -initialdir $p \
                -parent $top \
                -title [mc "Git Repository"] \
                -mustexist false]
        if {$p eq {}} return

        set p [file normalize $p]
        if {![_new_ok $p]} {
                return
        }
        set local_path $p
        $w_localpath icursor end
}

method _do_new2 {} {
        if {![_new_ok $local_path]} {
                return
        }
        if {![_git_init $this]} {
                return
        }
        set done 1
}

proc _new_ok {p} {
        if {[file isdirectory $p]} {
                if {[_is_git [file join $p .git]]} {
                        error_popup [mc "Directory %s already exists." $p]
                        return 0
                }
        } elseif {[file exists $p]} {
                error_popup [mc "File %s already exists." $p]
                return 0
        }
        return 1
}

######################################################################
##
## Clone Existing Repository

method _do_clone {} {
        global use_ttk NS
        $w_next conf \
                -state disabled \
                -command [cb _do_clone2] \
                -text [mc "Clone"]

        ${NS}::frame $w_body
        ${NS}::label $w_body.h \
                -font font_uibold -anchor center \
                -text [mc "Clone Existing Repository"]
        pack $w_body.h -side top -fill x -pady 10
        pack $w_body -fill x -padx 10

        set args $w_body.args
        ${NS}::frame $w_body.args
        pack $args -fill both

        ${NS}::label $args.origin_l -text [mc "Source Location:"]
        ${NS}::entry $args.origin_t \
                -textvariable @origin_url \
                -width 50
        ${NS}::button $args.origin_b \
                -text [mc "Browse"] \
                -command [cb _open_origin]
        grid $args.origin_l $args.origin_t $args.origin_b -sticky ew

        ${NS}::label $args.where_l -text [mc "Target Directory:"]
        ${NS}::entry $args.where_t \
                -textvariable @local_path \
                -width 50
        ${NS}::button $args.where_b \
                -text [mc "Browse"] \
                -command [cb _new_local_path]
        grid $args.where_l $args.where_t $args.where_b -sticky ew
        set w_localpath $args.where_t

        ${NS}::label $args.type_l -text [mc "Clone Type:"]
        ${NS}::frame $args.type_f
        set w_types [list]
        lappend w_types [${NS}::radiobutton $args.type_f.hardlink \
                -state disabled \
                -text [mc "Standard (Fast, Semi-Redundant, Hardlinks)"] \
                -variable @clone_type \
                -value hardlink]
        lappend w_types [${NS}::radiobutton $args.type_f.full \
                -state disabled \
                -text [mc "Full Copy (Slower, Redundant Backup)"] \
                -variable @clone_type \
                -value full]
        lappend w_types [${NS}::radiobutton $args.type_f.shared \
                -state disabled \
                -text [mc "Shared (Fastest, Not Recommended, No Backup)"] \
                -variable @clone_type \
                -value shared]
        foreach r $w_types {
                pack $r -anchor w
        }
        grid $args.type_l $args.type_f -sticky new

        grid columnconfigure $args 1 -weight 1

        trace add variable @local_path write [cb _update_clone]
        trace add variable @origin_url write [cb _update_clone]
        bind $w_body.h <Destroy> "
                [list trace remove variable @local_path write [cb _update_clone]]
                [list trace remove variable @origin_url write [cb _update_clone]]
        "
        update
        focus $args.origin_t
}

method _open_origin {} {
        if {$origin_url ne {} && [file isdirectory $origin_url]} {
                set p $origin_url
        } else {
                set p [pwd]
        }

        set p [tk_chooseDirectory \
                -initialdir $p \
                -parent $top \
                -title [mc "Git Repository"] \
                -mustexist true]
        if {$p eq {}} return

        set p [file normalize $p]
        if {![_is_git [file join $p .git]] && ![_is_git $p]} {
                error_popup [mc "Not a Git repository: %s" [file tail $p]]
                return
        }
        set origin_url $p
}

method _update_clone {args} {
        if {$local_path ne {} && $origin_url ne {}} {
                $w_next conf -state normal
        } else {
                $w_next conf -state disabled
        }

        if {$origin_url ne {} &&
                (  [_is_git [file join $origin_url .git]]
                || [_is_git $origin_url])} {
                set e normal
                if {[[lindex $w_types 0] cget -state] eq {disabled}} {
                        set clone_type hardlink
                }
        } else {
                set e disabled
                set clone_type full
        }

        foreach r $w_types {
                $r conf -state $e
        }
}

method _do_clone2 {} {
        if {[file isdirectory $origin_url]} {
                set origin_url [file normalize $origin_url]
        }

        if {$clone_type eq {hardlink} && ![file isdirectory $origin_url]} {
                error_popup [mc "Standard only available for local repository."]
                return
        }
        if {$clone_type eq {shared} && ![file isdirectory $origin_url]} {
                error_popup [mc "Shared only available for local repository."]
                return
        }

        if {$clone_type eq {hardlink} || $clone_type eq {shared}} {
                set objdir [_objdir $origin_url]
                if {$objdir eq {}} {
                        error_popup [mc "Not a Git repository: %s" [file tail $origin_url]]
                        return
                }
        }

        set giturl $origin_url
        if {[is_Cygwin] && [file isdirectory $giturl]} {
                set giturl [exec cygpath --unix --absolute $giturl]
                if {$clone_type eq {shared}} {
                        set objdir [exec cygpath --unix --absolute $objdir]
                }
        }

        if {[file exists $local_path]} {
                error_popup [mc "Location %s already exists." $local_path]
                return
        }

        if {![_git_init $this]} return
        set local_path [pwd]

        if {[catch {
                        git config remote.$origin_name.url $giturl
                        git config remote.$origin_name.fetch +refs/heads/*:refs/remotes/$origin_name/*
                } err]} {
                error_popup [strcat [mc "Failed to configure origin"] "\n\n$err"]
                return
        }

        destroy $w_body $w_next

        switch -exact -- $clone_type {
        hardlink {
                set o_cons [status_bar::two_line $w_body]
                pack $w_body -fill x -padx 10 -pady 10

                $o_cons start \
                        [mc "Counting objects"] \
                        [mc "buckets"]
                update

                if {[file exists [file join $objdir info alternates]]} {
                        set pwd [pwd]
                        if {[catch {
                                file mkdir [gitdir objects info]
                                set f_in [open [file join $objdir info alternates] r]
                                set f_cp [open [gitdir objects info alternates] w]
                                fconfigure $f_in -translation binary -encoding binary
                                fconfigure $f_cp -translation binary -encoding binary
                                cd $objdir
                                while {[gets $f_in line] >= 0} {
                                        if {[is_Cygwin]} {
                                                puts $f_cp [exec cygpath --unix --absolute $line]
                                        } else {
                                                puts $f_cp [file normalize $line]
                                        }
                                }
                                close $f_in
                                close $f_cp
                                cd $pwd
                        } err]} {
                                catch {cd $pwd}
                                _clone_failed $this [mc "Unable to copy objects/info/alternates: %s" $err]
                                return
                        }
                }

                set tolink  [list]
                set buckets [glob \
                        -tails \
                        -nocomplain \
                        -directory [file join $objdir] ??]
                set bcnt [expr {[llength $buckets] + 2}]
                set bcur 1
                $o_cons update $bcur $bcnt
                update

                file mkdir [file join .git objects pack]
                foreach i [glob -tails -nocomplain \
                        -directory [file join $objdir pack] *] {
                        lappend tolink [file join pack $i]
                }
                $o_cons update [incr bcur] $bcnt
                update

                foreach i $buckets {
                        file mkdir [file join .git objects $i]
                        foreach j [glob -tails -nocomplain \
                                -directory [file join $objdir $i] *] {
                                lappend tolink [file join $i $j]
                        }
                        $o_cons update [incr bcur] $bcnt
                        update
                }
                $o_cons stop

                if {$tolink eq {}} {
                        info_popup [strcat \
                                [mc "Nothing to clone from %s." $origin_url] \
                                "\n" \
                                [mc "The 'master' branch has not been initialized."] \
                                ]
                        destroy $w_body
                        set done 1
                        return
                }

                set i [lindex $tolink 0]
                if {[catch {
                                file link -hard \
                                        [file join .git objects $i] \
                                        [file join $objdir $i]
                        } err]} {
                        info_popup [mc "Hardlinks are unavailable.  Falling back to copying."]
                        set i [_copy_files $this $objdir $tolink]
                } else {
                        set i [_link_files $this $objdir [lrange $tolink 1 end]]
                }
                if {!$i} return

                destroy $w_body
        }
        full {
                set o_cons [console::embed \
                        $w_body \
                        [mc "Cloning from %s" $origin_url]]
                pack $w_body -fill both -expand 1 -padx 10
                $o_cons exec \
                        [list git fetch --no-tags -k $origin_name] \
                        [cb _do_clone_tags]
        }
        shared {
                set fd [open [gitdir objects info alternates] w]
                fconfigure $fd -translation binary
                puts $fd $objdir
                close $fd
        }
        }

        if {$clone_type eq {hardlink} || $clone_type eq {shared}} {
                if {![_clone_refs $this]} return
                set pwd [pwd]
                if {[catch {
                                cd $origin_url
                                set HEAD [git rev-parse --verify HEAD^0]
                        } err]} {
                        _clone_failed $this [mc "Not a Git repository: %s" [file tail $origin_url]]
                        return 0
                }
                cd $pwd
                _do_clone_checkout $this $HEAD
        }
}

method _copy_files {objdir tocopy} {
        $o_cons start \
                [mc "Copying objects"] \
                [mc "KiB"]
        set tot 0
        set cmp 0
        foreach p $tocopy {
                incr tot [file size [file join $objdir $p]]
        }
        foreach p $tocopy {
                if {[catch {
                                set f_in [open [file join $objdir $p] r]
                                set f_cp [open [file join .git objects $p] w]
                                fconfigure $f_in -translation binary -encoding binary
                                fconfigure $f_cp -translation binary -encoding binary

                                while {![eof $f_in]} {
                                        incr cmp [fcopy $f_in $f_cp -size 16384]
                                        $o_cons update \
                                                [expr {$cmp / 1024}] \
                                                [expr {$tot / 1024}]
                                        update
                                }

                                close $f_in
                                close $f_cp
                        } err]} {
                        _clone_failed $this [mc "Unable to copy object: %s" $err]
                        return 0
                }
        }
        return 1
}

method _link_files {objdir tolink} {
        set total [llength $tolink]
        $o_cons start \
                [mc "Linking objects"] \
                [mc "objects"]
        for {set i 0} {$i < $total} {} {
                set p [lindex $tolink $i]
                if {[catch {
                                file link -hard \
                                        [file join .git objects $p] \
                                        [file join $objdir $p]
                        } err]} {
                        _clone_failed $this [mc "Unable to hardlink object: %s" $err]
                        return 0
                }

                incr i
                if {$i % 5 == 0} {
                        $o_cons update $i $total
                        update
                }
        }
        return 1
}

method _clone_refs {} {
        set pwd [pwd]
        if {[catch {cd $origin_url} err]} {
                error_popup [mc "Not a Git repository: %s" [file tail $origin_url]]
                return 0
        }
        set fd_in [git_read for-each-ref \
                --tcl \
                {--format=list %(refname) %(objectname) %(*objectname)}]
        cd $pwd

        set fd [open [gitdir packed-refs] w]
        fconfigure $fd -translation binary
        puts $fd "# pack-refs with: peeled"
        while {[gets $fd_in line] >= 0} {
                set line [eval $line]
                set refn [lindex $line 0]
                set robj [lindex $line 1]
                set tobj [lindex $line 2]

                if {[regsub ^refs/heads/ $refn \
                        "refs/remotes/$origin_name/" refn]} {
                        puts $fd "$robj $refn"
                } elseif {[string match refs/tags/* $refn]} {
                        puts $fd "$robj $refn"
                        if {$tobj ne {}} {
                                puts $fd "^$tobj"
                        }
                }
        }
        close $fd_in
        close $fd
        return 1
}

method _do_clone_tags {ok} {
        if {$ok} {
                $o_cons exec \
                        [list git fetch --tags -k $origin_name] \
                        [cb _do_clone_HEAD]
        } else {
                $o_cons done $ok
                _clone_failed $this [mc "Cannot fetch branches and objects.  See console output for details."]
        }
}

method _do_clone_HEAD {ok} {
        if {$ok} {
                $o_cons exec \
                        [list git fetch $origin_name HEAD] \
                        [cb _do_clone_full_end]
        } else {
                $o_cons done $ok
                _clone_failed $this [mc "Cannot fetch tags.  See console output for details."]
        }
}

method _do_clone_full_end {ok} {
        $o_cons done $ok

        if {$ok} {
                destroy $w_body

                set HEAD {}
                if {[file exists [gitdir FETCH_HEAD]]} {
                        set fd [open [gitdir FETCH_HEAD] r]
                        while {[gets $fd line] >= 0} {
                                if {[regexp "^(.{40})\t\t" $line line HEAD]} {
                                        break
                                }
                        }
                        close $fd
                }

                catch {git pack-refs}
                _do_clone_checkout $this $HEAD
        } else {
                _clone_failed $this [mc "Cannot determine HEAD.  See console output for details."]
        }
}

method _clone_failed {{why {}}} {
        if {[catch {file delete -force $local_path} err]} {
                set why [strcat \
                        $why \
                        "\n\n" \
                        [mc "Unable to cleanup %s" $local_path] \
                        "\n\n" \
                        $err]
        }
        if {$why ne {}} {
                update
                error_popup [strcat [mc "Clone failed."] "\n" $why]
        }
}

method _do_clone_checkout {HEAD} {
        if {$HEAD eq {}} {
                info_popup [strcat \
                        [mc "No default branch obtained."] \
                        "\n" \
                        [mc "The 'master' branch has not been initialized."] \
                        ]
                set done 1
                return
        }
        if {[catch {
                        git update-ref HEAD $HEAD^0
                } err]} {
                info_popup [strcat \
                        [mc "Cannot resolve %s as a commit." $HEAD^0] \
                        "\n  $err" \
                        "\n" \
                        [mc "The 'master' branch has not been initialized."] \
                        ]
                set done 1
                return
        }

        set o_cons [status_bar::two_line $w_body]
        pack $w_body -fill x -padx 10 -pady 10
        $o_cons start \
                [mc "Creating working directory"] \
                [mc "files"]

        set readtree_err {}
        set fd [git_read --stderr read-tree \
                -m \
                -u \
                -v \
                HEAD \
                HEAD \
                ]
        fconfigure $fd -blocking 0 -translation binary
        fileevent $fd readable [cb _readtree_wait $fd]
}

method _readtree_wait {fd} {
        set buf [read $fd]
        $o_cons update_meter $buf
        append readtree_err $buf

        fconfigure $fd -blocking 1
        if {![eof $fd]} {
                fconfigure $fd -blocking 0
                return
        }

        if {[catch {close $fd}]} {
                set err $readtree_err
                regsub {^fatal: } $err {} err
                error_popup [strcat \
                        [mc "Initial file checkout failed."] \
                        "\n\n$err"]
                return
        }

        # -- Run the post-checkout hook.
        #
        set fd_ph [githook_read post-checkout [string repeat 0 40] \
                [git rev-parse HEAD] 1]
        if {$fd_ph ne {}} {
                global pch_error
                set pch_error {}
                fconfigure $fd_ph -blocking 0 -translation binary -eofchar {}
                fileevent $fd_ph readable [cb _postcheckout_wait $fd_ph]
        } else {
                set done 1
        }
}

method _postcheckout_wait {fd_ph} {
        global pch_error

        append pch_error [read $fd_ph]
        fconfigure $fd_ph -blocking 1
        if {[eof $fd_ph]} {
                if {[catch {close $fd_ph}]} {
                        hook_failed_popup post-checkout $pch_error 0
                }
                unset pch_error
                set done 1
                return
        }
        fconfigure $fd_ph -blocking 0
}

######################################################################
##
## Open Existing Repository

method _do_open {} {
        global NS
        $w_next conf \
                -state disabled \
                -command [cb _do_open2] \
                -text [mc "Open"]

        ${NS}::frame $w_body
        ${NS}::label $w_body.h \
                -font font_uibold -anchor center \
                -text [mc "Open Existing Repository"]
        pack $w_body.h -side top -fill x -pady 10
        pack $w_body -fill x -padx 10

        ${NS}::frame $w_body.where
        ${NS}::label $w_body.where.l -text [mc "Repository:"]
        ${NS}::entry $w_body.where.t \
                -textvariable @local_path \
                -width 50
        ${NS}::button $w_body.where.b \
                -text [mc "Browse"] \
                -command [cb _open_local_path]

        grid $w_body.where.l $w_body.where.t $w_body.where.b -sticky ew
        pack $w_body.where -fill x

        grid columnconfigure $w_body.where 1 -weight 1

        trace add variable @local_path write [cb _write_local_path]
        bind $w_body.h <Destroy> [list trace remove variable @local_path write [cb _write_local_path]]
        update
        focus $w_body.where.t
}

method _open_local_path {} {
        if {$local_path ne {}} {
                set p $local_path
        } else {
                set p [pwd]
        }

        set p [tk_chooseDirectory \
                -initialdir $p \
                -parent $top \
                -title [mc "Git Repository"] \
                -mustexist true]
        if {$p eq {}} return

        set p [file normalize $p]
        if {![_is_git [file join $p .git]]} {
                error_popup [mc "Not a Git repository: %s" [file tail $p]]
                return
        }
        set local_path $p
}

method _do_open2 {} {
        if {![_is_git [file join $local_path .git]]} {
                error_popup [mc "Not a Git repository: %s" [file tail $local_path]]
                return
        }

        if {[catch {cd $local_path} err]} {
                error_popup [strcat \
                        [mc "Failed to open repository %s:" $local_path] \
                        "\n\n$err"]
                return
        }

        _append_recentrepos [pwd]
        set ::_gitdir .git
        set ::_prefix {}
        set done 1
}

}