gkmid

#!/usr/bin/env php
<?php
  //default tempo
  $tempo = 60;
  $monada = 4;
  //beep executable
  $beep = "beep";

  //constant data
  $frequencies_table = array(
    "C" => 261.6,
    "C#" => 277.2,
    "D" => 293.7,
    "D#" => 311.1,
    "E" => 329.6,
    "F" => 349.2,
    "F#" => 370.0,
    "G" => 392.0,
    "G#" => 415.3,
    "A" => 440.0,
    "A#" => 466.2,
    "B" => 493.9
  );
  $note_line_pattern = "/^(?<notes>([a-gA-G]{1}\-?\d{1}#?,?)+)\s+(?<duration>\d+)(?<dotted>\*{0,2})$/";
  $note_pattern = "/^(?<note>[a-gA-G]{1})(?<octave>\-?\d{1})(?<sharp>#?)$/";
  $tempo_pattern = "/^%\s?(?<tempo>\d+)\/{1}(?<monada>\d+)$/";

  //parse options
  $cmdline_opts = getopt("t:f:",array("transpose:", "format:"));

  if (isset($cmdline_opts["t"])) {
    $transpose = $cmdline_opts["t"];
  } else if (isset($cmdline_opts["transpose"])) {
    $transpose = $cmdline_opts["transpose"];
  } else {
    $transpose = 0;
  }

  if (isset($cmdline_opts["f"])) {
    $format = $cmdline_opts["f"];
  } else if (isset($cmdline_opts["format"])) {
    $format = $cmdline_opts["format"];
  } else {
    $format = "beep-stdin";
  }

  if (count($argv) > 1) {
    $file = $argv[count($argv)-1];
  } else {
    die("No input files\n");
  }

  //code
  $content = file_get_contents($file);
  $notes = explode("\n", $content);

  foreach($notes as $line => $i) {
    if (empty($i)) {
      continue;
    }

    if ($i[0] == "%")
    {
      if (!preg_match($tempo_pattern, $i, $matches)) {
        error_log("Invalid syntax on tempo definition at $line");
        continue;
      }
      $tempo = $matches["tempo"];
      $monada = $matches["monada"];
    }
    else if ($i[0] != '#')
    {
      if (!preg_match($note_line_pattern, $i, $matches)) {
        error_log("Invalid syntax on note definition at $line");
        continue;
      }

      //frequencies calculation
      $freqs = array();
      $notes = explode(",", $matches["notes"]);
      foreach($notes as $j) {
        if (!empty($j)) {
          preg_match($note_pattern, $j, $note_parts);
          $note = $note_parts["note"] . $note_parts["sharp"];
          $freqs[] = $frequencies_table[$note] * pow(2, $note_parts["octave"] + $transpose);
        }
      }

      //duration calculation
      $duration = ($monada * 60) / ($tempo * $matches["duration"]);
      if (strlen($matches["dotted"] == 1)) {
        $duration *= 1.5;
      } else if (strlen($matches["dotted"] == 2)) {
        $duration *= 1.75;
      }
      $duration = ceil($duration * 1000);

      //multiplexing
      if (sizeof($freqs) > 1) {
//         $slots = $duration / 15;
//         while ($slots >= 1) {
//           $output_notes[] = array($freqs[$slots % count($freqs)], 15);
//           $slots--;
//         }
        $slot_time = 20;
        $slots = $duration / $slot_time;
        $note_index = 0;
        $note_dir = 1;
        for(;$slots >= 1; $slots--) {
          $output_notes[] = array($freqs[$note_index], $slot_time);
          if ($note_dir > 0 && $note_index >= (count($freqs) - 1)) {
            $note_dir = -1;
          } else if ($note_dir < 0 && $note_index == 0) {
            $note_dir = 1;
          }

          $note_index += $note_dir;
        }
      } else {
        $output_notes[] = array($freqs[0], $duration);
      }
    }
  }

  if (!isset($output_notes)) {
    die("Input file does not contain any notes\n");
  }

  switch($format) {
  case "c-array":
    echo "typedef struct _Note {\n\tfloat freq;\n\tunsigned short duration;\n} Note;\n\n";
    echo "Note notes[] = {\n";
    foreach($output_notes as $note) {
      echo "\t{" . $note[0] . ", " . $note[1] . "},\n";
    }
    echo "};\n";
    break;
  case "beep-stdin":
  default:
    foreach($output_notes as $note) {
      echo "$note[0] $note[1]\n";
    }
    break;
  }

?>