#!/usr/bin/perl
use warnings;
use strict;
use LWP::Simple;
use Encode qw/encode decode/;

# http://music.sogou.com/song/newtop_1.html

############################################################
use constant URL => "http://music.sogou.com/song/newtop_1.html";
use constant MAX => 20;
############################################################


if (! (-d "down_mp3")) {
	mkdir "down_mp3";
}
if (! (-d "down_mp3")) {
	print "cannot create directory: down_mp3\n";
	exit;
}

print "#### get top list... from  ", URL, "\n";
my $resp = get( URL );
my @songs;
my $i = 0;
while ($resp =~ m/width="153"(.*?)width="83"/gsm and $i < MAX) {
	my $tmp = $1;
	my ($t, $a);
	$tmp =~ m/title="([^"]+)"/;
	$t = encode("utf8", $1);
	$tmp =~ m/showSinger=t>([^<]+)<\//;
	$a = encode("utf8", $1);
	print "$a - $t\n";
	push @songs, {"artist" => $a, "title" => $t};

	$i++;
}
print "############################################################\n";
foreach (@songs) {
	my $a = $_->{artist};
	my $t = $_->{title};

	if ((not -e "down_mp3/$a - $t.mp3.aria2") and (-e "down_mp3/$a - $t.mp3" )) {
		print "# File exits already:\t$a - $t.mp3\n";
		next;
	}

	print "#### get the url of  $a - $t.mp3 ...\n";
	my $u = &get_best_url($_);


	if (defined $u) {
		&down($_, $u);
	}
	else {
		print "######## failed to get the url of  $a - $t.mp3 ...\n";
	}
}

exit;


sub down {
	my $a = $_[0]->{artist};
	my $t = $_[0]->{title};
	my $l = $_[1];


	if ( -e "down_mp3/$a - $t.mp3.aria2") {
		print "# Continue download: $a - $t.mp3\n";
		system("aria2c", "-q", "-o", "down_mp3/$a - $t.mp3", $l);
	}
	else {
		print "# Now downloading:\t$a - $t.mp3\n";
		system("aria2c", "-q", "-o", "down_mp3/$a - $t.mp3", $l);
	}
}

sub get_best_url {
	my $aa = $_[0]->{artist};
	my $t = $_[0]->{title};
	my ($r, $u);
	my @items;
	my @links;
	my $retry = 3;

	do {
		$r = get("http://mp3.sogou.com/music.so?query="
			. encode("gbk", decode("utf8", "$aa $t")));
		$retry--;
	} while ((! defined $r) and $retry);

	@items = ($r =~ /(<td class="songname">.*?)class="spd"/gms);
	foreach (@items) {
		$_ = encode("utf8", $_);
		my ($tmp_title, $tmp_artist, $tmp_url, $tmp_size);
		$_ =~ /songname.*?>([^<]+)</;
		$tmp_title = $1;
		next if not ($tmp_title =~ $t);

		$_ =~ /singer.*?>([^<]+)</;
		$tmp_artist = $1;
		next if not ($tmp_artist =~ $aa);

		$_ =~ /window\.open\('([^']+)'/;
		$tmp_url = "http://mp3.sogou.com$1";

		$_ =~ /nowrap>(.*?)</;
		$tmp_size = $1;
		next if not ($tmp_size =~ /M/i);
		$tmp_size =~ s/M//;

		$_ =~ /<td>(.{3})<\/td>/;
		next if not ($1 =~ /mp3/i);

		push @links, {"size" => "$tmp_size", "link" => "$tmp_url"};
	}
	return undef if ((scalar @links) == 0);

	@links = reverse sort {$a->{size} <=> $b->{size}} @links;


	foreach (@links) {
		$r = get($_->{link});
		$r =~ /url=(http:[^"']+)/g;
		$u = $1;
		last if (defined $u);
	}

	return $u;
}