#---8<---gadget-piano.ps1---Jean-JMST-Belgium---8<---

   #=9/2006===================================Version 1==========#
   #===========  "human hearable" string music notes ============#
   #
   # To use :
   #
   #  -music paremeter is a string containing music notes separated
   #   by a space.
   #
   #   A simplified abc notation is used.
   #   A music note begins with the keyboard's ocatve used (1, 2 or 3)
   #   followed by a character music note (from C to B) + eventually
   #   a # character indicating an half tone higher (sharp), so :
   #
   #    2F# is music note F sharp played on the second piano 
   #    keyboard's octave.
   #
   #   Values allowed for notes :
   #     C,C#,D,D#,E,F,F#,G,G#,A,A# and B
   #      preceded by 1,2 or 3
   #
   #   A silence is marked with a Z.
   #   
   #   To multiply a note duration, ie $black*2 : 3C2
   #   To divide a note duration, ie $black/4 : 3C/4
   #
   #  -black is the duration in millisecond a note is played
   #    default=200
   #
   #  -tempo is the duration between notes in milliseconds
   #    default=100
   #
   # To test :
   #
   #  .\gadget-piano
   #   °plays a little music
   #  .\gadget-piano "2A" 5000
   #   °plays a A note 5 seconds ... to tune your Stradivarius
   #  .\gadget-piano (("1F# Z ")*5) 300
   #   °plays a F sharp and a silence 5 times
   #  .\gadget-piano "1A 1B 1C 3A 3B 3C" 150 50
   #   °plays a sequence of notes, each one played 150 ms with
   #    an interval of 50 ms
   #
   # NOTE :
   #
   #  You must have a pc internal speaker present and enabled 
   #  to hear something :-)
   #
   #========Tested on PowerShell 1 RC2===========================#

   param(
         [string]$music='2C 2D 2E 2G 2F 2F 2A 2G 2G 3C 2B 3C 2G 2E 2C',
         [int]$black=200,
         [int]$tempo=100
        )
   
   filter play-sound{
    [console]::Beep(
                    [math]::Pow([math]::Pow(2,1/12),$_)*440,
                    $black*$ratio
                   )
   }

   $script:OFS=''

   $notes=('C','C#','D','D#','E','F','F#','G','G#','A','A#','B')
   $sounds=-21..14
   $keyboards=(($sounds[0..11]),($sounds[12..23]),($sounds[24..35]))
   $h=@{}

   for($i=1;$i -lt 4;$i++)
    {0..11|%{$h.Add("$i"+$notes[$_],$keyboards[$i-1][$_])}}
   [regex]$r='(\d)?([A-GZ])(#)?(/)?(\d)?(\-)?'
   $music.Split(' ',[StringSplitOptions]::RemoveEmptyEntries)|% `
     {
      if($_ -match $r){
       $ratio=1
       if($matches[4] -and $matches[5])
        {$ratio=invoke-expression ('1'+[string]$matches[4..5])}
       elseif($matches[5])
        {$ratio=invoke-expression ('1*'+[string]$matches[5])}
       if($matches[2] -eq 'Z'){Start-Sleep -m ($black*$ratio)}
       else{
           $note=$h[[string]($matches[1..3])]
           $note|play-sound
           }
       if(!$matches[6]){Start-Sleep -m $tempo}
      }
     }
  #---8<---gadget-piano.ps1---Jean-JMST-Belgium---8<---