IriSP.JSONSerializer = function(DataLoader, url) {

  IriSP.Serializer.call(this, DataLoader, url);

};

IriSP.JSONSerializer.prototype = new IriSP.Serializer();

IriSP.JSONSerializer.prototype.serialize = function(data) {

  return JSON.stringify(data);

};

IriSP.JSONSerializer.prototype.deserialize = function(data) {

  return JSON.parse(data);

};

IriSP.JSONSerializer.prototype.sync = function(callback) {

  /* we don't have to do much because jQuery handles json for us */

  var self = this;

  var fn = function(data) {      

      self._data = data;      

      // sort the data too     

      self._data["annotations"].sort(function(a, b) 

          { var a_begin = +a.begin;

            var b_begin = +b.begin;

            return a_begin - b_begin;

          });

      callback(data);      

  };

  this._DataLoader.get(this._url, fn);

};

IriSP.JSONSerializer.prototype.currentMedia = function() {  

  return this._data.medias[0]; /* FIXME: don't hardcode it */

};

/* this function searches for an annotation which matches title, description and keyword 

   "" matches any field. 

*/    

IriSP.JSONSerializer.prototype.searchAnnotations = function(title, description, keyword) {

    /* we can have many types of annotations. We want search to only look for regular segments */

    /* the next two lines are a bit verbose because for some test data, _serializer.data.view is either

       null or undefined.

    */

    var view;

    if (typeof(this._data.views) !== "undefined" && this._data.views !== null)

       view = this._data.views[0];

    var searchViewType = "";

    if(typeof(view) !== "undefined" && typeof(view.annotation_types) !== "undefined" && view.annotation_types.length > 1) {

            searchViewType = view.annotation_types[0];

    }

    var rTitle;

    var rDescription;

    var rKeyword;

    /* match anything if given the empty string */

    if (title == "")

      title = ".*";

    if (description == "")

      description = ".*";

    if (keyword == "")

      keyword = ".*";

    rTitle = new RegExp(title, "i");  

    rDescription = new RegExp(description, "i");  

    rKeyword = new RegExp(keyword, "i");  

    var ret_array = [];

    var i;

    for (i in this._data.annotations) {

      var annotation = this._data.annotations[i];

      /* filter the annotations whose type is not the one we want */

          continue;

      }

      if (rTitle.test(annotation.content.title) && 

          rDescription.test(annotation.content.description)) {

          /* FIXME : implement keyword support */

          ret_array.push(annotation);

      }

    }

    return ret_array;

};

/* breaks a string in words and searches each of these words. Returns an array

   of objects with the id of the annotation and its number of occurences.

   FIXME: optimize ? seems to be n^2 in the worst case.

*/

IriSP.JSONSerializer.prototype.searchOccurences = function(searchString) {

  var ret = { };

  var keywords = searchString.split(/\s+/);

  for (var i in keywords) {

    var keyword = keywords[i];

    // search this keyword in descriptions and title

    var found_annotations = []

    found_annotations = found_annotations.concat(this.searchAnnotations(keyword, "", ""));

    found_annotations = found_annotations.concat(this.searchAnnotations("", keyword, ""));

    for (var j in found_annotations) {

      var current_annotation = found_annotations[j];

      if (!ret.hasOwnProperty(current_annotation.id)) {

        ret[current_annotation.id] = 1;

      } else {

        ret[current_annotation.id] += 1;

      }

    }

  };

  return ret;

};

/* takes the currentTime and returns all the annotations that are displayable at the moment 

   NB: only takes account the first type of annotations - ignores tweets 

   currentTime is in seconds.

 */

IriSP.JSONSerializer.prototype.currentAnnotations = function(currentTime) {

  var view;

  var currentTimeMs = 1000 * currentTime;

  if (typeof(this._data.views) !== "undefined" && this._data.views !== null)

     view = this._data.views[0];

  var view_type = "";

  if(typeof(view) !== "undefined" && typeof(view.annotation_types) !== "undefined" && view.annotation_types.length >= 1) {

          view_type = view.annotation_types[0];

  }

  var ret_array = [];

  var i;

  for (i in this._data.annotations) {

    var annotation = this._data.annotations[i];

    if (annotation.meta["id-ref"] === view_type && annotation.begin <= currentTimeMs && annotation.end >= currentTimeMs)

      ret_array.push(annotation);

  }

  return ret_array;

};