package SoundOfMusicSong;
use strict;
use warnings;

my %SoM = (
    'c' => {phrase => 'a deer a female deer',       sound => 'do'},
    'd' => {phrase => 'a drop of golden sun',       sound => 're'},
    'e' => {phrase => 'a name I call myself',       sound => 'me'},
    'f' => {phrase => 'a long long way to run',     sound => 'fa'},
    'g' => {phrase => 'a needle pulling thread',    sound => 'so'},
    'a' => {phrase => 'a note to follow so',        sound => 'la'},
    'b' => {phrase => 'a drink with jam and bread', sound => 'te'},
    );
my @notes = keys %SoM;

sub make_SoM_song {
    my ($user_song) = @_;

    return [
        map {exists $SoM{$_} ? $SoM{$_}->{sound} : 'not a note'}
        split /\W+/, $user_song
        ];
}

sub getPhrase {
    my ($user_song) = @_;
    my $notes = make_SoM_song($user_song);
    my @new_song = map {$SoM{$_} ? "$_ $SoM{$_}" : 'not a note'} @$notes;
    return \@new_song;
}

sub random_SoM_note {
    return $SoM{$notes[rand @notes]}{sound};
}

sub random_SoM_song {
    my ($number_of_notes) = @_;

    $number_of_notes ||= int(rand(100)) + 1;
    return [map {random_SoM_note()} 1 .. $number_of_notes];
}

sub note_to_sound {
    my ($note) = @_;
    
    return $SoM{$note}{sound};
}