// utilities.js
// Copyright (C) 2008 University of California - San Diego

/**
 * Date extension to replace the way UTC strings are displayed.
 */
Date.prototype.toUTCString = function() {
  var Y = this.getUTCFullYear();
  var m = this.getUTCMonth()+1;
  if(m < 10) { m = "0" + m; }

  var d = this.getUTCDate();
  if(d < 10) { d = "0" + d; }

  var H = this.getUTCHours();
  if(H < 10) { H = "0" + H; }

  var M = this.getUTCMinutes();
  if(M < 10) { M = "0" + M; }

  var S = this.getUTCSeconds();
  if(S < 10) { S = "0" + S; }

  var Z = "UTC";

  return (Y+"-"+m+"-"+d+" "+H+":"+M+":"+S+" "+Z);
}


/**
 * Utility function to determin if param exists in array
 */
function in_array(p,a) { 
  for(var k in a) { 
    if(a[k] == p) { 
      return true;
    }
  }
  return false;
}


/*
 * Returns value of URL parameter, null if not found.
 */
function get_url_parameter(r) {
  // querystring
  var q = location.search.substring(1);
  // parameters
  var p = q.split("&");
  // loop through parameters
  for(var i=0,n=p.length; i<n; i++) {
    // key=value
    var s = p[i].split("=");
    // if key == requested key
    if( s[0] == r ) {
      // return value
      return s[1];
    }
  }
  return null;
}