git-gui: Add a search command to the blame viewer.

One of the largest deficiencies in the blame viewer at
the moment is the impossibility to search for a text
string. This commit fixes it by adding a Firefox-like
search panel to the viewer.

The panel can be shown by pressing F7 or clicking a
menu entry, and is hidden by pressing Esc. Find Next
is available through the F3 key.

Implementation is based on the gitk code, but heavily
refactored. It now also supports case-insensitive
searches, and uses the text box background color to
signal success or failure of the search.

Signed-off-by: Alexander Gavrilov <angavrilov@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

1 files changed, 190 insertions, 0 deletions

diff --git a/lib/search.tcl b/lib/search.tcl
new file mode 100644
index 0000000000..d292f20f66
--- /dev/null
+++ b/lib/search.tcl
@@ -0,0 +1,190 @@
+# incremental search panel
+# based on code from gitk, Copyright (C) Paul Mackerras
+
+class searchbar {
+
+field w
+field ctext
+
+field searchstring   {}
+field casesensitive  1
+field searchdirn     -forwards
+
+field smarktop
+field smarkbot
+
+constructor new {i_w i_text args} {
+	set w      $i_w
+	set ctext  $i_text
+
+	frame  $w
+	label  $w.l       -text [mc Find:]
+	button $w.bn      -text [mc Next] -command [cb find_next]
+	button $w.bp      -text [mc Prev] -command [cb find_prev]
+	checkbutton $w.cs -text [mc Case-Sensitive] \
+		-variable ${__this}::casesensitive -command [cb _incrsearch]
+	entry  $w.ent -textvariable ${__this}::searchstring -background lightgreen
+	pack   $w.l   -side left
+	pack   $w.cs  -side right
+	pack   $w.bp  -side right
+	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 searchstring write [cb _incrsearch_cb]
+	
+	bind $w <Destroy> [cb delete_this]
+	return $this
+}
+
+method show {} {
+	if {![winfo ismapped $w]} {
+		grid $w
+	}
+	focus -force $w.ent
+}
+
+method hide {} {
+	if {[winfo ismapped $w]} {
+		focus $ctext
+		grid remove $w
+	}
+}
+
+method _get_new_anchor {} {
+	# use start of selection if it is visible,
+	# or the bounds of the visible area
+	set top    [$ctext index @0,0]
+	set bottom [$ctext index @0,[winfo height $ctext]]
+	set sel    [$ctext tag ranges sel]
+	if {$sel ne {}} {
+		set spos [lindex $sel 0]
+		if {[lindex $spos 0] >= [lindex $top 0] &&
+		    [lindex $spos 0] <= [lindex $bottom 0]} {
+			return $spos
+		}
+	}
+	if {$searchdirn eq "-forwards"} {
+		return $top
+	} else {
+		return $bottom
+	}
+}
+
+method _get_wrap_anchor {dir} {
+	if {$dir eq "-forwards"} {
+		return 1.0
+	} else {
+		return end
+	}
+}
+
+method _do_search {start {mlenvar {}} {dir {}} {endbound {}}} {
+	set cmd [list $ctext search]
+	if {$mlenvar ne {}} {
+		upvar $mlenvar mlen
+		lappend cmd -count mlen
+	}
+	if {!$casesensitive} {
+		lappend cmd -nocase
+	}
+	if {$dir eq {}} {
+		set dir $searchdirn
+	}
+	lappend cmd $dir -- $searchstring
+	if {$endbound ne {}} {
+		set here [eval $cmd [list $start] [list $endbound]]
+	} else {
+		set here [eval $cmd [list $start]]
+		if {$here eq {}} {
+			set here [eval $cmd [_get_wrap_anchor $this $dir]]
+		}
+	}
+	return $here
+}
+
+method _incrsearch_cb {name ix op} {
+	after idle [cb _incrsearch]
+}
+
+method _incrsearch {} {
+	$ctext tag remove found 1.0 end
+	if {[catch {$ctext index anchor}]} {
+		$ctext mark set anchor [_get_new_anchor $this]
+	}
+	if {$searchstring ne {}} {
+		set here [_do_search $this anchor mlen]
+		if {$here ne {}} {
+			$ctext see $here
+			$ctext tag remove sel 1.0 end
+			$ctext tag add sel $here "$here + $mlen c"
+			$w.ent configure -background lightgreen
+			_set_marks $this 1
+		} else {
+			$w.ent configure -background lightpink
+		}
+	}
+}
+
+method find_prev {} {
+	find_next $this -backwards
+}
+
+method find_next {{dir -forwards}} {
+	focus $w.ent
+	$w.ent icursor end
+	set searchdirn $dir
+	$ctext mark unset anchor
+	if {$searchstring ne {}} {
+		set start [_get_new_anchor $this]
+		if {$dir eq "-forwards"} {
+			set start "$start + 1c"
+		}
+		set match [_do_search $this $start mlen]
+		$ctext tag remove sel 1.0 end
+		if {$match ne {}} {
+			$ctext see $match
+			$ctext tag add sel $match "$match + $mlen c"
+		}
+	}
+}
+
+method _mark_range {first last} {
+	set mend $first.0
+	while {1} {
+		set match [_do_search $this $mend mlen -forwards $last.end]
+		if {$match eq {}} break
+		set mend "$match + $mlen c"
+		$ctext tag add found $match $mend
+	}
+}
+
+method _set_marks {doall} {
+	set topline [lindex [split [$ctext index @0,0] .] 0]
+	set botline [lindex [split [$ctext index @0,[winfo height $ctext]] .] 0]
+	if {$doall || $botline < $smarktop || $topline > $smarkbot} {
+		# no overlap with previous
+		_mark_range $this $topline $botline
+		set smarktop $topline
+		set smarkbot $botline
+	} else {
+		if {$topline < $smarktop} {
+			_mark_range $this $topline [expr {$smarktop-1}]
+			set smarktop $topline
+		}
+		if {$botline > $smarkbot} {
+			_mark_range $this [expr {$smarkbot+1}] $botline
+			set smarkbot $botline
+		}
+	}
+}
+
+method scrolled {} {
+	if {$searchstring ne {}} {
+		after idle [cb _set_marks 0]
+	}
+}
+
+}
\ No newline at end of file