#!/usr/bin/perl

# NOTE: this thing needs documented, badly :-)
# and cleaned up. Rolling it out as is cause we're in a hurry.
# The code, however, does the job (the lib is the important part anyway).

use strict;
use JavaScript::Squish;
use Getopt::Long;
use File::Basename();

my $DEBUG = 0;


&Main();

sub Main
{
    my $opts = &load_options();

    die "Unable to read file [$$opts{src}]\n".&usage() unless -r $$opts{'src'};

    my $outfile = $$opts{'dest'};
    if ($outfile)
    {
        if (-e $outfile && $$opts{'force'}) {
            print STDERR "WARNING: output file [$outfile] exists. Overwritting in 2 seconds.\n";
            sleep 2;
        } elsif (-e $outfile) {
            die "Output file [$outfile] already exists.\nSpecify --force or remove the file prior to running.\n";
        }
        open(OUT, "> $outfile") or die "Unable to open output file [$outfile]\n";
    } else {
        *OUT = *STDOUT;
    }

    print STDERR "Reading in file...\n" if $DEBUG;
    die "Unable to read file [$$opts{src}]\n".&usage() unless open(IN,"< $$opts{'src'}");

    # slurp in the input
    my $data;
    { local($/); $data = <IN>; }
    close IN;

    my $js = JavaScript::Squish->new();
    $js->data($data);
    $js->determine_line_ending();

    if ($$opts{'remove_comments'})
    {
        if (@{$$opts{'comment_exception'}}) {
            $js->remove_comments(exceptions => $$opts{'comment_exception'});
        } else {
            $js->remove_comments();
        }
    }

    $js->extract_strings_and_comments();

    $js->replace_white_space() if $$opts{'replace_white_space'};
    $js->remove_blank_lines()  if $$opts{'remove_blank_lines'};
    $js->combine_concats()     if $$opts{'combine_concats'};
    $js->join_all()            if $$opts{'join_all'};
    $js->replace_extra_whitespace() if $$opts{'replace_extra_whitespace'};

    $js->restore_literal_strings();
    $js->restore_comments();

    $js->replace_final_eol();

    print OUT $js->data;

    close OUT if $outfile;
}

sub usage
{
    my $prog_name = File::Basename::basename($0);
    return "Usage $prog_name
    [--src=<source file>]
    [--dest=<destination file>]

    [--opt]  (do max squishing)

    [--comment_exception=<copyright>] (may specified multiple times)
    [--remove_coments]              (can negate with --no_...)
    [--replace_white_space]         (can negate with --no_...)
    [--remove_blank_lines]          (can negate with --no_...)
    [--combine_concats]             (can negate with --no_...)
    [--join_all]                    (can negate with --no_...)
    [--replace_extra_whitespace]    (can negate with --no_...)

    [--force]   (force overwrite of destination files)

    [--help]
\n";
}

sub load_options
{
    my %opts;
    $opts{'comment_exception'} = [];
    GetOptions(
        "src=s"                 => \$opts{'src'},
        "destination=s"         => \$opts{'dest'},
        "optimal"               => \$opts{'optimal'},
        "force"                 => \$opts{'force'},
        "comment_exception=s"   => $opts{'comment_exception'},

        "remove_comments"       => \$opts{'remove_comments'},
        "replace_white_space"   => \$opts{'replace_white_space'},
        "remove_blank_lines"    => \$opts{'remove_blank_lines'},
        "combine_concats"       => \$opts{'combine_concats'},
        "join_all"              => \$opts{'join_all'},
        "replace_extra_whitespace"  => \$opts{'replace_extra_whitespace'},

        "no_remove_comments"        => \$opts{'no_remove_comments'},
        "no_replace_white_space"    => \$opts{'no_replace_white_space'},
        "no_remove_blank_lines"     => \$opts{'no_remove_blank_lines'},
        "no_combine_concats"        => \$opts{'no_combine_concats'},
        "no_join_all"               => \$opts{'no_join_all'},
        "no_replace_extra_whitespace"   => \$opts{'no_replace_extra_whitespace'},
        ) or die &usage();

    if ($opts{'help'})
    {
        print &usage();
        exit(1);
    }
    if (! $opts{'src'})
    {
        print "Required option [src] not specified.\n\n";
        print &usage();
        exit(1);
    }

    my @bool_options = qw(remove_comments replace_white_space remove_blank_lines combine_concats join_all replace_extra_whitespace);

    # if none of the options were requested, assume default of --opt
    my $something_checked;
    foreach my $option (@bool_options) {
        $something_checked++ if $opts{$option};
    }

    # apply default optimal settings if specified
    # (or if nothing was checked).
    if ($opts{'optimal'} || (!$something_checked) )
    {
        $opts{'remove_comments'} = 1;
        $opts{'replace_white_space'} = 1;
        $opts{'remove_blank_lines'} = 1;
        $opts{'combine_concats'} = 1;
        $opts{'join_all'} = 1;
        $opts{'replace_extra_whitespace'} = 1;
    }

    # apply any negatives requested
    foreach my $neg (@bool_options)
    {
        if ($opts{'no_'.$neg})
        {
            $opts{$neg} = 0;
        }
    }

    # handle comment exceptions
    for (my $i=0; $i<@{$opts{'comment_exception'}}; $i++)
    {
        my $item = $opts{'comment_exception'}->[$i];
        $opts{'comment_exception'}->[$i] = qr/$item/i;
    }

    return \%opts;
}

=head1 NAME

js_compactor - Command line utility to reduce JavaScript code to as few characters as possible.

=head1 USAGE

 js_compactor -src=source_file [OPTIONS]

=head1 SYNOPSIS

js_compactor
[--src=source_file]
[--dest=destination_file]
[--opt]
[--comment_exception=text]
[--remove_coments]
[--replace_white_space]
[--remove_blank_lines]
[--combine_concats]
[--join_all]
[--replace_extra_whitespace]
[--no_remove_coments]
[--no_replace_white_space]
[--no_remove_blank_lines]
[--no_combine_concats]
[--no_join_all]
[--no_replace_extra_whitespace]
[--force]
[--help]

=head1 DESCRIPTION

The "--src" option is requied.

Default usage is as though you specified "--opt", for optimal settings. Setting any of the specific settings will override the default "--opt" behavior, and rules will be applied one by one. You may also specify "--opt" and then disable specific features with a "--no_option_name" style option.

=over

=item B<--src=filename>

The source javascript filename. (REQUIRED)

=item B<--dest=filename>

The destination file. Defaults to output to STDOUT.

=item B<--force>

Force overwriting of output file if it exists.

=item B<--opt>

Same as B<--remove_coments --replace_white_space --remove_blank_lines --combine_concats --join_all --replace_extra_whitespace>

=item B<--comment_exception=text_to_match>

Comments matching the provided text will NOT be removed. The primary purpose for this is to retain copyright notices. Eg.

    js_compator --comment_exception=copyright -src=somefile

This option may be specified multiple times. Any comment matching any of the provided strings will then be retained.

It uses a case insenstive regexp for the match. This option has no effect if --no_remove_comments is specified.

=item B<--remove_comments> | B<--no_remove_comments>

Remove all comments from the source.

=item B<--replace_white_space> | B<--no_replace_white_space>

Per each line:

=over

=item * Removes all begining of line whitespace.

=item * Removes all end of line whitespace.

=item * Combined all series of whitespace into one space character (eg.  s/\s+/ /g)

=back

Comments and string literals (if still embeded) are untouched.

=item B<--remove_blank_lines> | B<--no_remove_blank_lines>

Blank lines in code are removed.

=item B<--combine_concats> | B<--no_combine_concats>

Removes any string literal concatenations. Eg.

    "bob and " +   "sam " + someVar;

Becomes:

    "bob and sam " + someVar

=item B<--join_all> | B<--no_join_all>

Put everything on one line (retained comments may still contain new lines).

=item B<--replace_extra_whitespace> | B<--no_replace_extra_whitespace>

This removes any excess whitespace. Eg.

    if (someVar = "foo") {

Becomes:

    if(someVar="foo"){

=back

=head1 EXAMPLES

The normal use is probably just for one off squishings:

    js_compactor --src=input_file > new_file.js

If you're squishing something with a copyright, it is recommended that you retain that copyright:

    js_compactor --comment_exception=copyright --src=input_file > new_file.js

If you want the code to still be somewhat readable, it is often helpful to retain all the line breaks:

    js_compactor --opt --no_join_all --comment_exception=copyright --src=input_file > new_file.js

=head1 SEE ALSO

L<JavaScript::Squish>

=head1 BUGS

Please refer to http://developer.berlios.de/projects/jscompactor/ to report bugs.

=head1 AUTHOR

Joshua I. Miller <jmiller@puriifeddata.net>

=head1 COPYRIGHT AND LICENSE

Copyright (c) 2005 by CallTech Communications, Inc.

This library is free software; you can redistribute it and/or modify it
under the same terms as Perl itself, either Perl version 5.8.3 or, at
your option, any later version of Perl 5 you may have available.

=cut