#! perl -w
# Author:   Bert Muennich
# Website:  http://www.github.com/muennich/urxvt-perls
# Based on: http://www.jukie.net/~bart/blog/urxvt-url-yank
# License:  GPLv2

# Use keyboard shortcuts to select URLs.
# This should be used as a replacement for the default matcher extension,
# it also makes URLs clickable with the middle mouse button.

# Usage: put the following lines in your .Xdefaults/.Xresources:
#   URxvt.perl-ext-common: ...,url-select
#   URxvt.keysym.M-u: perl:url-select:select_next

# Use Meta-u to activate URL selection mode, then use the following keys:
#   j/k:      Select next downward/upward URL (also with arrow keys)
#   g/G:      Select first/last URL (also with home/end key)
#   o/Return: Open selected URL in browser, Return: deactivate afterwards
#   y:        Copy (yank) selected URL and deactivate selection mode
#   q/Escape: Deactivate URL selection mode

# Options:
#   URxvt.url-select.autocopy:  If true, selected URLs are copied to PRIMARY
#   URvxt.url-select.button:    Mouse button to click-open URLs (default: 2)
#   URxvt.url-select.launcher:  Browser/command to open selected URL with
#   URxvt.url-select.underline: If set to true, all URLs get underlined

use strict;

# The custom rendition bit to use for marking the cell as being underlined
# by us so we can unset it again after a line has changed.
use constant UNDERLINED => 1<<3; # arbitrarily chosen in hope of no collision

sub on_start {
	my ($self) = @_;

	# read resource settings
	if ($self->x_resource('url-select.launcher')) {
		@{$self->{browser}} = split /\s+/, $self->x_resource('url-select.launcher');
	} else {
		@{$self->{browser}} = ('x-www-browser');
	}
	if ($self->x_resource('url-select.underline') eq 'true') {
		$self->enable(line_update => \&line_update);
	}
	if ($self->x_resource('url-select.autocopy') eq 'true') {
		$self->{autocopy} = 1;
	}

	$self->{state} = 0;

	for my $mod (split '', $self->x_resource("url-select.button") ||
	                       $self->x_resource("matcher.button") || 2) {
		if ($mod =~ /^\d+$/) {
			$self->{button} = $mod;
		} elsif ($mod eq "C") {
			$self->{state} |= urxvt::ControlMask;
		} elsif ($mod eq "S") {
			$self->{state} |= urxvt::ShiftMask;
		} elsif ($mod eq "M") {
			$self->{state} |= $self->ModMetaMask;
		} elsif ($mod ne "-" && $mod ne " ") {
			warn("invalid button/modifier in $self->{_name}<$self->{argv}[0]>: $mod\n");
		}
	}

	if ($self->x_resource('matcher.pattern')) {
		@{$self->{pattern}} = ($self->x_resource('matcher.pattern'));
	} elsif ($self->x_resource('matcher.pattern.0')) {
		my $current = 0;

		while (defined (my $res = $self->x_resource("matcher.pattern.$current"))) {
			$res = $self->locale_decode($res);
			utf8::encode $res;
			push @{$self->{pattern}}, qr($res)x;
			$current++;
		}
	} else {
		@{$self->{pattern}} = qr{
			(?:https?://|ftp://|news://|mailto:|file://|\bwww\.)
			[\w\-\@;\/?:&=%\$.+!*\x27,~#]*
			(
				\([\w\-\@;\/?:&=%\$.+!*\x27,~#]*\)   # Allow a pair of matched parentheses
				|                                    #
				[\w\-\@;\/?:&=%\$+*~]                # exclude some trailing characters (heuristic)
			)+
		}x;
	}

	()
}


sub line_update {
	my ($self, $row) = @_;

	my $line = $self->line($row);
	my $text = $line->t;
	my $rend = $line->r;

	# clear all underlines that were set by us
	for (@$rend) {
		if (urxvt::GET_CUSTOM($_) & UNDERLINED) {
			$_ = urxvt::SET_CUSTOM($_, urxvt::GET_CUSTOM($_) & ~UNDERLINED) &
			     ~urxvt::RS_Uline;
		}
	}

	for my $pattern (@{$self->{pattern}}) {
		while ($text =~ /$pattern/g) {
			my $url = $&;
			my ($beg, $end) = ($-[0], $+[0] - 1);

			for (@{$rend}[$beg .. $end]) {
				unless ($_ & urxvt::RS_Uline) {
					$_ = urxvt::SET_CUSTOM($_, urxvt::GET_CUSTOM($_) | UNDERLINED);
					$_ |= urxvt::RS_Uline;
				}
			}
		}
	}

	$line->r($rend);

	()
}

sub on_action {
    my ($self, $action) = @_;

    on_user_command($self, "url-select:" . $action);
}


sub on_user_command {
	my ($self, $cmd) = @_;

	if ($cmd eq 'url-select:select_next') {
		if (not $self->{active}) {
			activate($self);
		}
		select_next($self, -1);
	}

	()
}


sub key_press {
	my ($self, $event, $keysym) = @_;
	my $char = chr($keysym);

	if ($keysym == 0xff1b || lc($char) eq 'q' ||
	    (lc($char) eq 'c' && $event->{state} & urxvt::ControlMask)) {
		deactivate($self);
	} elsif ($keysym == 0xff0d || $char eq 'o') {
		$self->exec_async(@{$self->{browser}}, ${$self->{found}[$self->{n}]}[4]);
		deactivate($self) unless $char eq 'o';
	} elsif ($char eq 'y') {
		my $found = $self->{found}[$self->{n}];
		$self->selection_beg(${$found}[0], ${$found}[1]);
		$self->selection_end(${$found}[2], ${$found}[3]);
		$self->selection_make($event->{time});
		$self->selection_beg(1, 0);
		$self->selection_end(1, 0);
		deactivate($self);
	} elsif ($char eq 'k' || $keysym == 0xff52 || $keysym == 0xff51) {
		select_next($self, -1, $event);
	} elsif ($char eq 'j' || $keysym == 0xff54 || $keysym == 0xff53) {
		select_next($self, 1, $event);
	} elsif ($char eq 'g' || $keysym == 0xff50) {
		$self->{row} = $self->top_row - 1;
		delete $self->{found};
		select_next($self, 1, $event);
	} elsif ($char eq 'G' || $keysym == 0xff57) {
		$self->{row} = $self->nrow;
		delete $self->{found};
		select_next($self, -1, $event);
	}

	return 1;
}


sub on_button_press {
	my ($self, $event) = @_;

	my $mask = $self->ModLevel3Mask | $self->ModMetaMask |
	           urxvt::ShiftMask | urxvt::ControlMask;

	if ($event->{button} == $self->{button} && ($event->{state} & $mask) == $self->{state}) {
		my $col = $event->{col};
		my $row = $event->{row};
		my $line = $self->line($row);
		my $text = $line->t;

		for my $pattern (@{$self->{pattern}}) {
			while ($text =~ /$pattern/g) {
				my ($url, $beg, $end) = ($&, $-[0], $+[0]);
				--$end if $url =~ s/["')]$//;

				if ($col >= $beg && $col <= $end) {
					$self->{button_pressed} = 1;
					$self->{button_col} = $col;
					$self->{button_row} = $row;
					$self->{button_url} = $url;
					return 1;
				}
			}
		}
	}

	()
}

sub on_button_release {
	my ($self, $event) = @_;

	if ($self->{button_pressed} && $event->{button} == $self->{button}) {
		my $col = $event->{col};
		my $row = $event->{row};

		$self->{button_pressed} = 0;

		if ($col == $self->{button_col} && $row == $self->{button_row}) {
			$self->exec_async(@{$self->{browser}}, $self->{button_url});
			return 1;
		}
	}

	()
}


sub select_next {
	# $dir < 0: up, > 0: down
	my ($self, $dir, $event) = @_;
	my $row = $self->{row};

	if (($dir < 0 && $self->{n} > 0) ||
			($dir > 0 && $self->{n} < $#{ $self->{found} })) {
		# another url on current line
		$self->{n} += $dir;
		hilight($self);
		if ($self->{autocopy}) {
			my $found = $self->{found}[$self->{n}];
			$self->selection_beg(${$found}[0], ${$found}[1]);
			$self->selection_end(${$found}[2], ${$found}[3]);
			$self->selection_make($event->{time});
			$self->selection_beg(1, 0);
			$self->selection_end(1, 0);
		}
		return;
	}

	while (($dir < 0 && $row > $self->top_row) ||
	       ($dir > 0 && $row < $self->nrow - 1)) {
		my $line = $self->line($row);
		$row = ($dir < 0 ? $line->beg : $line->end) + $dir;
		$line = $self->line($row);
		my $text = $line->t;

		for my $pattern (@{$self->{pattern}}) {
			if ($text =~ /$pattern/g) {
				delete $self->{found};

				do {
					my ($beg, $end) = ($-[0], $+[0]);
					push @{$self->{found}}, [$line->coord_of($beg),
							$line->coord_of($end), substr($text, $beg, $end - $beg)];
				} while ($text =~ /$pattern/g);

				$self->{row} = $row;
				$self->{n} = $dir < 0 ? $#{$self->{found}} : 0;
				hilight($self);
				if ($self->{autocopy}) {
					my $found = $self->{found}[$self->{n}];
					$self->selection_beg(${$found}[0], ${$found}[1]);
					$self->selection_end(${$found}[2], ${$found}[3]);
					$self->selection_make($event->{time});
					$self->selection_beg(1, 0);
					$self->selection_end(1, 0);
				}
				return;
			}
		}
	}

	deactivate($self) unless $self->{found};

	()
}


sub hilight {
	my ($self) = @_;

	if ($self->{found}) {
		if ($self->{row} < $self->view_start() ||
				$self->{row} >= $self->view_start() + $self->nrow) {
			# scroll selected url into visible area
			my $top = $self->{row} - ($self->nrow >> 1);
			$self->view_start($top < 0 ? $top : 0);
		}

		status_area($self);
		$self->want_refresh();
	}

	()
}


sub refresh {
	my ($self) = @_;

	if ($self->{found}) {
		if ($self->x_resource('highlightColor')) {
			$self->scr_xor_span(@{$self->{found}[$self->{n}]}[0 .. 3], urxvt::RS_Sel);
		} else {
			$self->scr_xor_span(@{$self->{found}[$self->{n}]}[0 .. 3], urxvt::RS_RVid);
		}
	}

	()
}


sub status_area {
	my ($self) = @_;

	my $row = $self->{row} < 0 ?
			$self->{row} - $self->top_row : abs($self->top_row) + $self->{row};
	my $text = sprintf("%d,%d ", $row + 1, $self->{n} + 1);

	if ($self->top_row == 0) {
		$text .= "All";
	} elsif ($self->view_start() == $self->top_row) {
		$text .= "Top";
	} elsif ($self->view_start() == 0) {
		$text .= "Bot";
	} else {
		$text .= sprintf("%2d%",
				($self->top_row - $self->view_start) * 100 / $self->top_row);
	}

	my $text_len = length($text);

	if ($self->{overlay_len} != $text_len) {
		delete $self->{overlay} if $self->{overlay};
		$self->{overlay} = $self->overlay(-1, -1, $text_len, 1,
				urxvt::OVERLAY_RSTYLE, 0);
		$self->{overlay_len} = $text_len;
	}

	$self->{overlay}->set(0, 0, $self->special_encode($text));
	$self->{overlay}->show();

	()
}


sub tt_write {
	return 1;
}


sub activate {
	my ($self) = @_;

	$self->{active} = 1;

	$self->{row} = $self->view_start() + $self->nrow;
	$self->{n} = 0;
	$self->{overlay_len} = 0;
	$self->{button_pressed} = 0;

	$self->{view_start} = $self->view_start();
	$self->{pty_ev_events} = $self->pty_ev_events(urxvt::EV_NONE);

	$self->enable(
		key_press     => \&key_press,
		refresh_begin => \&refresh,
		refresh_end   => \&refresh,
		tt_write      => \&tt_write,
	);

	()
}


sub deactivate {
	my ($self) = @_;

	$self->disable("key_press", "refresh_begin", "refresh_end", "tt_write");
	$self->view_start($self->{view_start});
	$self->pty_ev_events($self->{pty_ev_events});

	delete $self->{overlay} if $self->{overlay};
	delete $self->{found} if $self->{found};

	$self->want_refresh();

	$self->{active} = 0;

	()
}