# goto line number
# based on code from gitk, Copyright (C) Paul Mackerras

class linebar {

field w
field ctext

field linenum   {}

constructor new {i_w i_text args} {
        global use_ttk NS
        set w      $i_w
        set ctext  $i_text

        ${NS}::frame  $w
        ${NS}::label  $w.l       -text [mc "Goto Line:"]
        tentry  $w.ent \
                -textvariable ${__this}::linenum \
                -background lightgreen \
                -validate key \
                -validatecommand [cb _validate %P]
        ${NS}::button $w.bn      -text [mc Go] -command [cb _goto]

        pack   $w.l   -side left
        pack   $w.bn  -side right
        pack   $w.ent -side left -expand 1 -fill x

        eval grid conf $w -sticky we $args
        grid remove $w

        trace add variable linenum write [cb _goto_cb]
        bind $w.ent <Return> [cb _goto]
        bind $w.ent <Escape> [cb hide]

        bind $w <Destroy> [list delete_this $this]
        return $this
}

method show {} {
        if {![visible $this]} {
                grid $w
        }
        focus -force $w.ent
}

method hide {} {
        if {[visible $this]} {
                $w.ent delete 0 end
                focus $ctext
                grid remove $w
        }
}

method visible {} {
        return [winfo ismapped $w]
}

method editor {} {
        return $w.ent
}

method _validate {P} {
        # only accept numbers as input
        string is integer $P
}

method _goto_cb {name ix op} {
        after idle [cb _goto 1]
}

method _goto {{nohide {0}}} {
        if {$linenum ne {}} {
                $ctext see $linenum.0
                if {!$nohide} {
                        hide $this
                }
        }
}

}