#! perl
# 
# Step 1 : pl2bat this file.
# Step 2 : add an action for MP3 file types in the explorer
#          for me, this was located under Folder Options.
#          I used an action of "De&tail" and set
#          "Application used to perform action" to
#          C:\projects\emplalia\emp.bat "%1".
#          Adjust the filename to something appropriate.
# Step 3 : Right click on an mp3 file and select Detail
#          You can view & alter the Album, Artist, Song
#          Title and Track Number
# 


use Wx;

package MyApp;
use MP3::Tag;
use File::Copy;
use File::Path;

use strict;
use Win32;
use vars qw(@ISA);
use Wx qw(wxDefaultSize wxDefaultPosition);
@ISA=qw(Wx::App);






sub OnInit {
  my( $this ) = @_;
  
  my( $dialog ) = MyDialog->new( "MP3 details",wxDefaultPosition);

  $this->SetTopWindow($dialog);

  $dialog->Show(1);
  1;
}

package MyDialog;

use strict;
use vars qw(@ISA);

@ISA=qw(Wx::Dialog);

use Wx::Event qw(EVT_CLOSE EVT_BUTTON);
use Wx qw(wxDefaultSize wxDefaultValidator wxOK wxICON_INFORMATION wxTE_READONLY);
use File::Copy;
use File::Path;
#
#   alter these 3 items to create different directories & filenames
#
my $sortdir="F:/sorted mp3/";
my $pathPattern = '$sortdir$artist/$album/';
my $fnPattern = '$sortdir$artist/$album/$artist - $album - $track - $song';
($sortdir, $pathPattern, $fnPattern) = loadPatterns();
sub new {
    my( $class ) = shift;
    my( $this ) = $class->SUPER::new( undef, -1, $_[0], $_[1], [250, 310] );
    my $fieldwidth = 170;
    # grab the mp3 information
    my $fn = Win32::GetLongPathName (@ARGV[0]);
    my $mp3=MP3::Tag->new($fn) || die $!;;
    my ($song, $track, $artist, $album) = $mp3->autoinfo();
    $mp3->close();
    $mp3=undef;
    $song =~s/^\s*//; # leading space trim
    # done with mp3 info
    
    #create the gui controls
    Wx::StaticText->new ($this,-1,"filename",[10,10],[100,-1]);
    Wx::StaticText->new ($this,-1,"artist",[10,40],[100,-1]);
    Wx::StaticText->new ($this,-1,"album",[10,70],[100,-1]);
    Wx::StaticText->new ($this,-1,"track #",[10,100],[100,-1]);
    Wx::StaticText->new ($this,-1,"song title",[10,130],[100,-1]);
    my($fnTXT) = $this->{FILENAME} = Wx::TextCtrl->new( $this, -1, $fn, [60, 10], [$fieldwidth, -1], wxTE_READONLY);
    my($arTXT) = $this->{ARTIST} = Wx::TextCtrl->new( $this, -1, $artist, [60, 40], [$fieldwidth, -1]);
    my($alTXT) = $this->{ALBUM} = Wx::TextCtrl->new( $this, -1, $album, [60, 70], [$fieldwidth, -1]);
    my($trTXT) = $this->{TRACK} = Wx::TextCtrl->new( $this, -1, $track, [60, 100], [$fieldwidth, -1]);
    my($snTXT) = $this->{SONG} = Wx::TextCtrl->new( $this, -1, $song, [60, 130], [$fieldwidth, -1]);
    my($okBTN) = Wx::Button->new( $this, -1, 'OK', [5, 160] );
    my($llBTN) = Wx::Button->new( $this, -1, 'Load Last', [85, 160] );
    my($caBTN) = Wx::Button->new( $this, -1, 'Cancel', [165, 160] );
    my($osBTN) = Wx::Button->new( $this, -1, 'OK && Sort', [5, 190] );
    
    EVT_BUTTON( $this, $okBTN, \&okBTN );
    EVT_BUTTON( $this, $caBTN, \&OnClose );
    EVT_BUTTON ($this, $llBTN, \&loadLast);
    EVT_BUTTON ($this, $osBTN, \&oksortBTN);
    EVT_CLOSE( $this, \&OnClose );
    
    return $this;
}

sub okBTN {
    #update and save tags, then close
    my ($this) = @_;
    updateMP3Tag($this);
    saveTagData($this);
    $this->OnClose();
}

sub oksortBTN {
    # update and save tags, move file and close
    my ($this) = @_;
    updateMP3Tag ($this);
    saveTagData ($this);    
    archiveMP3 ($this);
    $this->OnClose();
}

sub updateMP3Tag {
    # update tags...
    my ($this) = @_;
    my $id;
    my $mpeg=MP3::Tag->new($this->{FILENAME}->GetValue());
    $mpeg->get_tags();
    my $id;
    if (exists $mpeg->{ID3v2}){        
        $id = $mpeg->{ID3v2};
    } else {
        $id = $mpeg->new_tag("ID3v2");
    }
    unless ($id){
        # something's seriously funky here. The only time I've seen this scenario is
        # on a file with an old id3v2 tag.
        showWarningMessage($this, "Could not create or find tag",
            "Could not create or find an id3v2 tag for this file for some reason",
            "The file may have a ID3v2 tag that can't be coped with, or the file may be in use.", 
            "(perl reports $!)");
        return; # used to be OnClose, decided to let user have a chance to cope with problem :)
    }
    $id->remove_frame ($_) foreach (qw (TIT2 TALB TPE1 TRCK));
    $id->add_frame("TIT2", $this->{SONG}->GetValue());                   
    $id->add_frame("TALB", $this->{ALBUM}->GetValue());         
    $id->add_frame("TPE1", $this->{ARTIST}->GetValue());
    $id->add_frame("TRCK", $this->{TRACK}->GetValue());        
    unless ($id->write_tag()) { 
        showWarningMessage ($this, "Can't update tag","Couldn't write updated tag information",
            "(Is the file in use by another program?)","(perl reports $!)");
        return; # used to be OnClose, decided to let user have a chance to cope with problem :)        
    }        
}

sub saveTagData {
    # saves tag data to a text file for later loading.    
    my ($this) = @_;    
    my $cfgfn = "emp.cfg"; # configuration file name        
    open FH, ">$cfgfn" || print " no open $!";
    print FH join "\n",
        $this->{SONG}->GetValue(),
        $this->{ALBUM}->GetValue(),
        $this->{ARTIST}->GetValue(),
        $this->{TRACK}->GetValue();
    close FH;
}    

sub archiveMP3 {
    #moves & renames file to user specified info (see loadPatterns)
    my ($this) = @_;
    my ($fn, $song, $album, $artist, $track) = 
        ($this->{FILENAME}->GetValue(),
		 $this->{SONG}->GetValue(),
         $this->{ALBUM}->GetValue(),
         $this->{ARTIST}->GetValue(),
         $this->{TRACK}->GetValue());
         
         
    # clean up the track information         
    if ($track=~m|(\d+)\D+/\D+\d+|){ # deal with n/nn tracks as simply being track "n"
        $track =$1
    }      
    $track =~s |(\d+)/\d+|$1|;
    $track = sprintf ("%02d",$track);
    
    # make sure file path exists/ can be created 
    my $path = eval "\"$pathPattern\"";    
    eval {mkpath ($path)};
    if ($@) { # failed to create the new path. This will not occur if the path already exists
        showWarningMessage($this,"File name too damn long", "Could not create specified path '$sortdir$artist/$album'",
                        "Please deal with this file on your own.");
        return; # exit early; don't make a file on a path that doesn't exist                        
    }        

    # now move the file over
    my $newfn = eval "\"$fnPattern\"";
    $newfn .=".mp3";
    if (length $newfn >259) {
        # The maximum length of a path, including drive, directory
        # and filename is 259 characters. The maximum length of the 
        # filename portion of a path is 255 characters.
        showWarningMessage($this, "File name too damn long",
            "resulting filename '$newfn' would be greater that 255 characters.",
            "Please deal with this file on your own.");
        return; # no continue;                        
    }
    

    if (-e $newfn) { 
        # does  the file already exist? don't bother copying if it does
        # TODO : ask user if he wants to delete the file or overwrite target;
        showWarningMessage($this, "Can't move file","File '$newfn' already exists.");
        return;                         
        
    }
    
    unless (move ($fn, $newfn)) {
        showWarningMessage($this, "AAAIIEE", "Couldn't move this file.\n(Perl reports $!)");
    } 
    
}    

sub loadLast {
    # load last corrected tag minus track name.
    # increments track # by one as well
    my( $this ) = @_;
    my $cfgfn = "c:/emp.cfg";        
    open FH, $cfgfn || print $!;;
    my @lines=<FH>;
    close FH;
    chomp @lines;
    print join "\n", @lines;
    $this->{ALBUM}->SetValue($lines[1]);
    $this->{ARTIST}->SetValue($lines[2]);
    if ($lines[3]=~m|(\d+)\D+/\D+(\d+)|) { #attempt to preserve n/nn track numbering
        my $temp =$1 + 1;
        $this->{TRACK}->SetValue( "$temp/$2");        
    } else {
        $this->{TRACK}->SetValue(++$lines[3]);    
    }
    $this->{ARTIST}->SetValue($lines[2]);
    $this->{ALBUM}->SetValue($lines[1]);
}

sub loadPatterns {
    my ($sortdir,$pathPattern, $fnPattern);
    my @defaults = ("F:/sorted mp3/",
        '$sortdir$artist/$album/',
        '$sortdir$artist/$album/$artist - $album - $track - $song');
    open FH, "emplex.pat" || warn $!; # it's not really a requirement
    my @temp = <FH>;
    close FH;
    chomp @temp;
    for (0..2) {
        $temp[$_] = defined $temp[$_] ? $temp[$_] : $defaults[$_];
    }
    return @temp;
}

sub OnClose {
  my( $this, $event ) = @_;
  $this->Destroy();
}

sub showWarningMessage {
    my $this = shift;
    my $title = shift || "Infomational note";
    Wx::MessageBox( join ("\n", @_),$title, wxOK | wxICON_INFORMATION, $this );
}

package main;
my( $app ) = MyApp->new();
$app->MainLoop();