#!/usr/bin/perl -w
##############################################################################
# Create an fvwm menu for the most recently used applications and documents
# Optionally provide titles and icons in the menu
# Applications should be logged thus:
# echo "`date +%Y:%m:%d:%H:%M`,program,options" >> $DB
# titles may be specified thus:
# fvwmtitlestring:appname
# e.g 
# Mahjongg%gnome-mahjongg.png%:mahjongg
# By default anything over 1 day old is ignored. Anything used less than 
# once (sic) is ignored. Both of these values are configurable.
#
# documents are done differently. I have a shell function which logs edits
# to a file, separated by spaces. I use the same file here. The format 
# looks like this (without the leading '#')
#/tmp/log /home/cro/sh/launch.sh /home/cro/pl/showrecent.pl
#
# Author: Chris Rouch
# Date: 05/05/2004
# Changelog:
#
# Copyright (c) Chris Rouch 2004
#
#     This program is free software; you can redistribute it and/or modify
#     it under the terms of the GNU General Public License as published by
#     the Free Software Foundation; either version 2 of the License, or
#     (at your option) any later version.
# 
#     This program is distributed in the hope that it will be useful,
#     but WITHOUT ANY WARRANTY; without even the implied warranty of
#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#     GNU General Public License for more details.
# 
#     You should have received a copy of the GNU General Public License
#     along with this program; if not, write to the Free Software
#     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#     or see http://www.gnu.org/licenses/gpl.txt
##############################################################################
use strict;
use Getopt::Long;
use Time::Local;

# constants
use constant HOURS => 60*60;
use constant COUNT => 1;
use constant MAX => 20;
use constant TIME => 24; #Hours
use constant MENU => "Recent";
use constant MENUTITLE => "Most Recent";
use constant DB => "$ENV{HOME}/.launchdb";
use constant EDHIST => "$ENV{HOME}/.edhistory";
use constant TITLES => "$ENV{HOME}/.launchtitles";

# general global variables
use vars qw ($PROG $USAGE $OPTIONS);
use vars qw (%db %count %opts %titles @edit);
# command line variables
my $time=TIME;		    # max time ago in minutes (0 means no max)
my $count=COUNT;	    # min count
my $max=MAX;		    # max number of entries (0 means no max)
my $db=DB;		    # db to use
my $titles=TITLES;	    # list of titles
my $menu=MENU;		    # menu name to use
my $menutitle=MENUTITLE;    # menu title to use
my $verbose;		    # make some noise
my $purge;		    # remove entries older than $time

# command line switch
my %opts=
(
 "d|db=s" => \$db,
 "t|time=s" => \$time,
 "m|menu=s" => \$menu,
 "title=s" => \$menutitle,
 "c|count=s" => \$count,
 "v|verbose" => \$verbose,
 "p|purge" => \$purge,
);
($PROG=$0) =~ s!.*/!!;
SetUsage(\%opts,\$OPTIONS);

$USAGE="Usage: $PROG $OPTIONS";
die "$USAGE\n" unless GetOptions(%opts);

# program begins here
ReadDB(\%db,\%count,\%opts);
if (%db) {
    if ($purge) {
	PurgeDB(\%db,\%opts);
    }
    else {
	ReadTitles(\%titles);
	ReadEdit(\@edit);
	WriteMenu(\%db,\%count,\%opts,\%titles);
	WriteEdit(\@edit)
    }
}
############### end of main #############
sub PurgeDB {
    my ($rdb,$ropts) = @_;
    my ($year,$month,$day,$hour,$min,$apptime);
    return unless ($time > 0);
    foreach my $app (keys %$rdb) {
	($year,$month,$day,$hour,$min) = split(/:/,$$rdb{$app});
	$apptime=timelocal(0,$min,$hour,$day,$month-1,$year-1900);
 	my $diff = time - $apptime;
	if ((time - $apptime) > ($time*HOURS)) {
	    # too old
	    delete $$rdb{$app};
	    print "deleted $app: $year,$month,$day,$hour,$min\n" if ($verbose);
	}
	else {
	    print "$app is still current\n" if ($verbose);
	}
    }
    open(O,">$db") or die "failed to open $db for writing - $!\n";
    foreach my $app (sort {$$rdb{$a} cmp $$rdb{$b}} keys %$rdb) {
	print O "$$rdb{$app},$app,$$ropts{$app}\n";
    }
    close(O) or die "failed to update $db\n";
}
sub ReadTitles {
    my ($rtitles) = @_;
    my ($app,$title);
    if (open(I,$titles)) {
	while (<I>) {
	    next if m!^\s*$!; # ignore blanks
	    chomp;
	    ($title,$app) = split(/:/);
	    $$rtitles{$app} = $title;
# 	    print ">$app< = $title\n";
	}
	close(I);
    }
}
sub ReadDB {
    my ($rdb,$rcount,$ropts) = @_;
    my ($timestamp,$app,$opts);
    if (open(I,$db)) {
	while (<I>) {
	    chomp;
	    ($timestamp,$app,$opts) = split(/,/);
	    $$rcount{$app}++;
	    $$rdb{$app} = $timestamp; # always use latest
	    $$ropts{$app} = $opts; # use last opts
	}
	close(I);
    }
}
sub WriteMenu {
    my ($rdb,$rcount,$ropts,$rtitles) = @_;
    my ($year,$month,$day,$hour,$min,$apptime,$title,$entries);
    # prune based on count
    foreach my $app (keys %$rcount) {
	if ($$rcount{$app} < $count) {
	    delete $$rcount{$app};
	    delete $$rdb{$app};
	}
    }
    # prune based on time
    if ($time > 0) {
	foreach my $app (keys %$rdb) {
	    ($year,$month,$day,$hour,$min) = split(/:/,$$rdb{$app});
	    $apptime=timelocal(0,$min,$hour,$day,$month-1,$year-1900);
	    if ((time - $apptime) > ($time*HOURS)) {
		# too old
		delete $$rcount{$app};
		delete $$rdb{$app};
	    }
# 	    print "$app apptime $apptime\n";
	}
    }
    print qq[DestroyMenu recreate "$menu"\n];
    print qq[AddToMenu "$menu" "Recent Applications" Title\n];
    # sort it in most recent=first order
    $entries=0;
    foreach my $app (sort {$$rdb{$b} cmp $$rdb{$a}} keys %$rdb) {
# 	print "app $app $$rtitles{$app}\n";
	if ($$rtitles{$app}) {
	    $title=$$rtitles{$app}
	}
	else {
	    $title=$app;
	}
	print qq[AddToMenu "$menu" "$title" Exec exec launch $app $$ropts{$app}\n];
	$entries++;
	if (($max > 0) and ($entries >= $max)) {
 	    last;
 	}
    }
    
}
sub ReadEdit {
    my ($redit) = @_;
    if (open(I,EDHIST)) {
	while (<I>) {
	    chomp;
	    push(@$redit,split);
	}
	close(I);
    }
}
sub WriteEdit {
    my ($redit) = @_;
    print qq[AddToMenu "$menu" "Recent Documents" Title\n];
    foreach my $file (@$redit) {
	print qq[AddToMenu "$menu" "edit $file%emacs.png%" Exec exec launch editor $file\n];
    }

}
sub SetUsage {
    my ($ropts,$rstr) = @_;
    foreach my $key (keys %$ropts) {
	if ($key =~ /\|/) {
	    $key=~ s!^.*\|!!;
	}
	if ($key =~ /=/) {
	    $key =~ s!=.*$! value!;
	}
	$key = '-' . $key;
	$$rstr .= '[' . $key . '] ';
    }
}
############### end of file #############