#!/usr/bin/perl -w
# ggh - grovel global history in netscape logs
$USAGE = <<EO_COMPLAINT;
usage: $0 [-database dbfilename] [-help]
           [-epochtime | -localtime | -gmtime]
           [ [-regexp] pattern] | href ... ]
EO_COMPLAINT

use Getopt::Long;

($opt_database, $opt_epochtime, $opt_localtime,
 $opt_gmtime,   $opt_regexp,    $opt_help,
 $pattern,                                  )      = (0) x 7;

usage() unless GetOptions qw{ database=s
                              regexp=s
                              epochtime localtime gmtime
                              help
                            };

if ($opt_help) { print $USAGE; exit; }

usage("only one of localtime, gmtime, and epochtime allowed")
    if $opt_localtime + $opt_gmtime + $opt_epochtime > 1;

if ( $opt_regexp ) {
    $pattern = $opt_regexp;
} elsif (@ARGV && $ARGV[0] !~ m(://)) {
    $pattern = shift;
}

usage("can't mix URLs and explicit patterns")
    if $pattern && @ARGV;

if ($pattern && !eval { '' =~ /$pattern/; 1 } ) {
    $@ =~ s/ at \w+ line \d+\.//;
    die "$0: bad pattern $@";
}

require DB_File; DB_File->import();  # delay loading until runtime
$| = 1;                              # feed the hungry PAGERs

$dotdir  = $ENV{HOME}    || $ENV{LOGNAME};
$HISTORY = $opt_database || "$dotdir/.netscape/history.db";

die "no netscape history dbase in $HISTORY: $!" unless -e $HISTORY;
die "can't dbmopen $HISTORY: $!" unless dbmopen %hist_db, $HISTORY, 0666;

# the next line is a hack because the C programmers who did this
# didn't understand strlen vs strlen+1.  jwz told me so. :-)
$add_nulls   = (ord(substr(each %hist_db, -1)) == 0);

# XXX: should now do scalar keys to reset but don't 
#      want cost of full traverse, required on tied hashes.
#   better to close and reopen?

$nulled_href = "";  
$byte_order  = "V";         # PC people don't grok "N" (network order)
    
if (@ARGV) {
    foreach $href (@ARGV) {
        $nulled_href = $href . ($add_nulls && "\0");
        unless ($binary_time = $hist_db{$nulled_href}) {
            warn "$0: No history entry for HREF $href\n";
            next;
        }
        $epoch_secs = unpack($byte_order, $binary_time);
        $stardate   = $opt_epochtime ? $epoch_secs
                                     : $opt_gmtime ? gmtime    $epoch_secs
                                                   : localtime $epoch_secs;
        print "$stardate $href\n";
    }
} else {
    while ( ($href, $binary_time) = each %hist_db ) {
        chop $href if $add_nulls;
        # gnat reports some binary times are missing
        $binary_time = pack($byte_order, 0) unless $binary_time;
        $epoch_secs = unpack($byte_order, $binary_time);
        $stardate   = $opt_epochtime ? $epoch_secs
                                     : $opt_gmtime ? gmtime    $epoch_secs
                                                   : localtime $epoch_secs;
        print "$stardate $href\n" unless $pattern && $href !~ /$pattern/o;
    }
}

sub usage {
    print STDERR "@_\n" if @_;
    die $USAGE;
}