/** @class This class implement a serializer for the JSON-Cinelab format

    @params DataLoader a dataloader reference

    @url the url from which to get our cinelab

 */

IriSP.JSONSerializer = function(DataLoader, url) {

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

};

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

/** serialize data */

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

  return JSON.stringify(data);

};

/** deserialize data */

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

  return JSON.parse(data);

};

/** load JSON-cinelab data and also sort the annotations by start time

    @param callback function to call when the data is ready.

 */

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

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

  var self = this;

  var fn = function(data) {

	  //TODO: seems taht data can be null here

	  if (data !== null) {

		  self._data = data;  

	      if (typeof(self._data["annotations"]) === "undefined" ||

	          self._data["annotations"] === null)

	          self._data["annotations"] = [];

	      // 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, force_refresh);

};

/** @return the metadata about the media being read FIXME: always return the first media. */

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

  return (typeof this._data.medias == "object" && this._data.medias.length) ? this._data.medias[0] : IriSP.__jsonMetadata.medias[0];

};

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

    var _m = this.currentMedia();

    if (_m === null || typeof _m.meta == "undefined") {

        return 0;

    }

    return +(IriSP.get_aliased(_m.meta, ["dc:duration", "duration"]) || 0);

}

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

   "" matches any field. 

   Note: it ignores tweets.

   @return a list of matching ids.

*/    

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 filterfn = function(annotation) {

      if( searchViewType  != "" && 

          typeof(annotation.meta) !== "undefined" && 

          typeof(annotation.meta["id-ref"]) !== "undefined" &&

          annotation.meta["id-ref"] !== searchViewType) {

        return true; // don't pass

      } else {

          return false;

      }

    };

    return this.searchAnnotationsFilter(title, description, keyword, filterfn);

};

/* only look for tweets */

IriSP.JSONSerializer.prototype.searchTweets = 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 searchViewType = this.getTweets();

    if (typeof(searchViewType) === "undefined") {

      var view;

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

         view = this._data.views[0];    

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

              searchViewType = view.annotation_types[0];

      }

    }

    var filterfn = function(annotation) {

      if( searchViewType  != "" && 

          typeof(annotation.meta) !== "undefined" && 

          typeof(annotation.meta["id-ref"]) !== "undefined" &&

          annotation.meta["id-ref"] === searchViewType) {

        return false; // pass

      } else {

          return true;

      }

    };

    return this.searchAnnotationsFilter(title, description, keyword, filterfn);

};

/**

  search an annotation according to its title, description and keyword

  @param filter a function to filter the results with. Used to select between annotation types.

 */    

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

    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 */

      if (filter(annotation)) {

          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.

   @param searchString a string of words.

   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;

};

/** 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.searchTweetsOccurences = 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.searchTweets(keyword, "", ""));

    found_annotations = found_annotations.concat(this.searchTweets("", 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;

};

/** 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.

   @param currentTime the time at which we search.

   @param (optional) the if of the type of the annotations we want to get.

 */

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

  var view;

  var currentTimeMs = 1000 * currentTime;

  if (typeof(id) === "undefined") {

      var legal_ids = this.getNonTweetIds();

  } else {

      legal_ids = [id];

  }

  var ret_array = [];

  var i;

  for (i in this._data.annotations) {

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

    if (IriSP.underscore.include(legal_ids, annotation.meta["id-ref"]) && 

        annotation.begin <= currentTimeMs &&

        annotation.end >= currentTimeMs)

          ret_array.push(annotation);

  }

  if (ret_array == []) {

    console.log("ret_array empty, ", legal_ids);

  }

  return ret_array;

};

/** return the current chapitre

    @param currentTime the current time, in seconds.

*/

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

  return this.currentAnnotations(currentTime, this.getChapitrage())[0];

};

/** returns a list of ids of tweet lines (aka: groups in cinelab) */

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

  if (IriSP.null_or_undefined(this._data.lists) || IriSP.null_or_undefined(this._data.lists) ||

      IriSP.null_or_undefined(this._data.views) || IriSP.null_or_undefined(this._data.views[0]))

    return [];

  /* Get the displayable types

     We've got to jump through a few hoops because the json sometimes defines

     fields with underscores and sometimes with dashes

  */

  var annotation_types = IriSP.get_aliased(this._data.views[0], ["annotation_types", "annotation-types"]);

  if (annotation_types === null) {

      console.log("neither view.annotation_types nor view.annotation-types are defined");      

      return;

  }

  var available_types = IriSP.get_aliased(this._data, ["annotation_types", "annotation-types"]);    

  if (available_types === null) {

      console.log("neither view.annotation_types nor view.annotation-types are defined");      

      return;

  }

  var potential_types = [];

  // Get the list of types which contain "Tw" in their content

  for (var i = 0; i < available_types.length; i++) {

    if (/Tw/i.test(IriSP.get_aliased(available_types[i], ['dc:title', 'title']))) {

      potential_types.push(available_types[i].id);

    }

  }

  // Get the intersection of both.

  var tweetsId = IriSP.underscore.intersection(annotation_types, potential_types);

  return tweetsId;

};

/** this function returns a list of lines which are not tweet lines */

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

  if (IriSP.null_or_undefined(this._data.lists) || IriSP.null_or_undefined(this._data.lists) ||

      IriSP.null_or_undefined(this._data.views) || IriSP.null_or_undefined(this._data.views[0]))

    return [];

  /* Get the displayable types

     We've got to jump through a few hoops because the json sometimes defines

     fields with underscores and sometimes with dashes

  */

  var annotation_types = IriSP.get_aliased(this._data.views[0], ["annotation_types", "annotation-types"]);

  if (annotation_types === null) {

      console.log("neither view.annotation_types nor view.annotation-types are defined");      

      return;

  }

  var available_types = IriSP.get_aliased(this._data, ["annotation_types", "annotation-types"]);    

  if (available_types === null) {

      console.log("neither view.annotation_types nor view.annotation-types are defined");      

      return;