File Coverage

blib/lib/Podcast/ESLPodcast/Splitter.pm

Criterion	Covered	Total	%
statement	16	18	88.8
branch			n/a
condition			n/a
subroutine	6	6	100.0
pod			n/a
total	22	24	91.6

package Podcast::ESLPodcast::Splitter;

use warnings;
use strict;
use Carp;

use LWP::UserAgent;
use File::Basename;
use XML::FeedPP;
use MP3::Splitter;
use Data::Dumper;
use Time::Piece;
use List::MoreUtils qw(any all);

use version; our $VERSION = qv('0.0.1');

use constant FEEDURI =>
  'http://feeds.feedburner.com/EnglishAsASecondLanguagePodcast?format=xml';

# constructor
sub new {
    my ( $class, @args ) = @_;
    my %args = ref $args[0] eq 'HASH' ? %{ $args[0] } : @args;
    my $self = {%args};
    $self->{n} ||= 5;
    bless $self, $class;
}

# fetch a feed information for the ESLPodcast
sub fetch_feed {
    my $feed = XML::FeedPP->new(FEEDURI);
    printf STDERR "===============FEED INFO================\n";
    printf STDERR "Title: %s\n",     $feed->title;
    printf STDERR "Date: %s\n",      $feed->pubDate;
    printf STDERR "Copyright: %s\n", $feed->copyright;
    printf STDERR "Link: %s\n",      $feed->link;
    printf STDERR "Language: %s\n",  $feed->language;
    printf STDERR "========================================\n";
    return $feed;
}

sub run {
    my $self     = shift;
    my $feed     = fetch_feed();
    my $num_mp3s = 1;
    for my $item ( $feed->get_item() ) {
        if ( $item->title =~ /English Cafe/ ) {
            printf STDERR "skip: %s\n", $item->title;
            next;
        }
        last if ( $num_mp3s > $self->{n} );

        printf STDERR "\tURL: %s\n\tTitle: %s\n\tguid: %s\n\tDescription: %s\n",
          $item->link, $item->title, $item->guid, "";    # $item->description;

        my $durations = extract_durations( $item->description );
        next if ( !$durations );

        my $uri      = $item->guid();
        my $mp3_file = basename($uri);
        if ( !download_mp3( \$uri, \$mp3_file ) ) {
            printf STDERR "download failure: %s\n", $mp3_file;
            next;
        }
        if ( split_mp3( \$mp3_file, $durations ) ) {
            printf STDERR "split failure: %s\n", $mp3_file;
        }

        ++$num_mp3s;
    }
    printf STDERR "DONE!";
}

# extract durations for each dialog
sub extract_durations {
    my ($desc) = @_;

    # find started at
    my $started_at = { slow => undef, explanation => undef, fast => undef };
    for ( split( /[\n|\r\n]/, $desc ) ) {
        chomp;
        if (/Slow (dialog|dialogue):\s*(\d+:\d+)/) {
            $started_at->{slow} = $2;
        }
        if (/Explanations:\s*(\d+:\d+)/) {
            $started_at->{explanation} = $1;
        }
        if (/Fast (dialog|dialogue):\s*(\d+:\d+)/) {
            $started_at->{fast} = $2;
        }
    }

    # print Dumper($started_at);
    if ( !( all { defined($_) } values %$started_at ) ) {
        printf STDERR "something wrong in this feed\n";
        return 0;
    }

    # find durations
    my $durations = { slow => undef, explanation => undef, fast => undef };
    $durations->{slow} = [
        $started_at->{slow},
        find_duration( $started_at->{explanation}, $started_at->{slow} )
    ];
    $durations->{explanation} = [
        $started_at->{explanation},
        find_duration( $started_at->{fast}, $started_at->{explanation} )
    ];
    $durations->{fast} = [ $started_at->{fast}, "=INF" ];
    return $durations;
}

# find a duration
sub find_duration {
    my ( $from, $to ) = @_;
    my $t1 = Time::Piece->strptime( $from, "%M:%S" );
    my $t2 = Time::Piece->strptime( $to,   "%M:%S" );
    my $diff = $t2 - $t1;
    return $diff->seconds;
}

# split a mp3 file into three files
sub split_mp3 {
    my ( $mp3_file, $durations ) = @_;
    mp3split(
        $$mp3_file, { verbose => 1 },
        $durations->{start}, $durations->{explanation},
        $durations->{fast}
    );
    return 1;
}

# download a mp3 file
sub download_mp3 {
    my ( $uri, $mp3_file ) = @_;
    open( my $fh, '>', $$mp3_file ) or die "$$mp3_file: $!";
    my $res = LWP::UserAgent->new->get(
        $$uri,
        ':content_cb' => sub {
            my ( $chunk, $res, $proto ) = @_;
            print $fh $chunk;
            my $size = tell $fh;
            if ( my $total = $res->header('Content-Length') ) {
                printf "%d/%d (%f%%)\r", $size, $total, $size / $total * 100;
            }
            else {
                printf "%d/Unknown bytes\r", $size;
            }
        }
    );
    close $fh;
    print "\n", $res->status_line, "\n";
    unlink $$mp3_file if ( !$res->is_success );
    return $res->is_success;
}

1;    # Magic true value required at end of module
__END__