--- iselect.pl	2007/10/25 12:45:18	4
+++ iselect.pl	2007/10/25 14:55:00	9
@@ -2,7 +2,7 @@
 
 use strict;
 use Term::Screen;
-use Carp qw/confess/;
+use Carp qw/cluck/;
 use Data::Dump qw/dump/;
 
 my $data = <<'EOF';
@@ -30,6 +30,8 @@
 }
 close($ps);
 
+$data .= "\n--EOF--";
+
 my $scr;
 
 # leave sane terminal if script dies
@@ -40,7 +42,7 @@
 
 my @lines = split(/\n/, $data);
 
-my $o = 0;	# offset in original text
+my $top_screen_line = 0;	# offset in original text
 my $pos = 0;
 
 # default: select first line
@@ -48,12 +50,13 @@
 my $status_text = '';
 my $error_text = '';
 
+my $status_lines = 3;
 
 # find which lines are selectable in input file
 my $selectable_line;
 
 for my $l (0 .. $#lines) {
-	if ($lines[$l] !~ s/^{s}//) {
+	if ($lines[$l] =~ s/^{s}//) {
 		$selectable_line->{$l}++;
 	}
 }
@@ -73,8 +76,8 @@
 
 sub chunk {
 	my $t = shift;
-	return unless length($t) > 2;
-	return substr($t,1,$scr->cols);
+	cluck "expected line" unless defined $t;
+	return substr($t,0,$scr->cols);
 }
 
 sub redraw_line {
@@ -88,22 +91,22 @@
 }
 
 sub redraw {
-	for my $l (0 .. $scr->rows - 3) {
-		my $line = $lines[ $l + $o ];
-		next if (length($line) < 2);
+	for my $l (0 .. $scr->rows - $status_lines) {
+		my $line = $lines[ $l + $top_screen_line ];
 		redraw_line( $l, $line );
 		last if ($l == $#lines);
 	}
+	selected(0);
 }
 
 sub status {
 	my $pcnt = int(($pos || 0) * 100 / ($#lines || 1));
 	my $pos_txt = sprintf('%d, %d%% ',$pos,$pcnt);
 	
-	$scr->at($scr->rows - 2,0)->reverse()->puts(
+	$scr->at($scr->rows - $status_lines + 1,0)->reverse()->puts(
 		sprintf(' %-'.($scr->cols - length($pos_txt) - 2).'s ',$status_text)
 	.$pos_txt)->normal();
-	$scr->at($scr->rows - 1,0)->puts(
+	$scr->at($scr->rows - $status_lines + 2,0)->puts(
 		sprintf('%-'.$scr->cols.'s', $error_text)
 	);
 }
@@ -111,22 +114,24 @@
 sub selected {
 	my $d = shift || 0;
 
-	my $screen_line = $pos - $o;
+	my $screen_line = $pos - $top_screen_line;
 
 	redraw_line( $screen_line, $lines[$pos] );
 
-	my $last_screen_line = $scr->rows - 3;
+	my $last_screen_line = $scr->rows - $status_lines;
 
 	if ( $d < 0 && $screen_line == 0 ) {
 		if ( $pos > 0 ) {
-			$o--;
+			$top_screen_line--;
+			$pos--;
 		} else {
 			$error_text = "Already at Begin.";
 		}
 		redraw;
 	} elsif ( $d > 0 && $screen_line == $last_screen_line ) {
-		if ( $pos <= $#lines ) {
-			$o++;
+		if ( $pos < $#lines ) {
+			$top_screen_line++;
+			$pos++;
 		} else {
 			$error_text = "Already at End.";
 		}
@@ -137,10 +142,10 @@
 
 	my $line = $lines[$pos];
 	if ( defined $selectable_line->{ $pos } ) {
-		$scr->at($pos - $o,0)->reverse->bold()->puts( full_line( chunk($line) ) )->normal();
+		$scr->at($pos - $top_screen_line,0)->reverse->bold()->puts( full_line( chunk($line) ) )->normal();
 		$sel_pos = $pos;
 	} else {
-		$scr->at($pos - $o,0)->reverse->puts( full_line( chunk($line) ) );
+		$scr->at($pos - $top_screen_line,0)->reverse->puts( full_line( chunk($line) ) );
 		$sel_pos = -1;
 	}
 	status;
@@ -155,13 +160,31 @@
 
 	$error_text = "";
 
+	my $lines_on_screen = $scr->rows - $status_lines;
+
 	if ($key eq 'ku') {
 		selected( -1 );
 	} elsif ($key eq 'kd') {
 		selected( +1 );
+	} elsif ($key eq 'pgup' ) {
+		# first line on screen?
+		if ( $pos == $top_screen_line ) {
+			$top_screen_line -= $lines_on_screen;
+			$top_screen_line = 0 if $top_screen_line < 0;
+			redraw;
+		}
+		selected( -( $pos - $top_screen_line ) );
+	} elsif ($key eq 'pgdn' ) {
+		# last line on screen?
+		if ( $pos - $top_screen_line == $lines_on_screen ) {
+			$top_screen_line += $lines_on_screen;
+			$top_screen_line = $#lines - $lines_on_screen if $top_screen_line >= $#lines - $lines_on_screen;
+			redraw;
+		}
+		selected( $top_screen_line + $lines_on_screen - $pos );
 	}
 
-	$status_text = sprintf("pos: %-3d sel_pos: %-3d top offset: %-3d", $pos, $sel_pos, $o );
+	$status_text = sprintf("pos: %-3d sel_pos: %-3d top_screen_line: %-3d", $pos, $sel_pos, $top_screen_line );
 	if ( length($key) > 1 ) {
 		$status_text .= " key: $key";
 	} else {
@@ -170,7 +193,8 @@
 
 	status;
 
-	redraw if lc($key) eq 'r';
+	# CTRL+L
+	redraw if ord($key) eq 0x0c;
 
 	exit if (lc($key) eq 'q');
 }