/**
 * Creation of the SectorMixin var.
 *
 * This contains all the functions the Graph object can use to employ the sector system.
 * The sector system is always used by Graph, though the benefits only apply to the use of clustering.
 * If clustering is not used, there is no overhead except for a duplicate object with references to nodes and edges.
 *
 * Alex de Mulder
 * 21-01-2013
 */
var SectorMixin = {

  /**
   * This function is only called by the setData function of the Graph object.
   * This loads the global references into the active sector. This initializes the sector.
   *
   * @private
   */
  _putDataInSector : function() {
    this.sectors["active"][this._sector()].nodes = this.nodes;
    this.sectors["active"][this._sector()].edges = this.edges;
    this.sectors["active"][this._sector()].nodeIndices = this.nodeIndices;
  },


  /**
   *  /**
   * This function sets the global references to nodes, edges and nodeIndices back to
   * those of the supplied (active) sector. If a type is defined, do the specific type
   *
   * @param {String} sectorId
   * @param {String} [sectorType] | "active" or "frozen"
   * @private
   */
  _switchToSector : function(sectorId, sectorType) {
    if (sectorType === undefined || sectorType == "active") {
      this._switchToActiveSector(sectorId);
    }
    else {
      this._switchToFrozenSector(sectorId);
    }
  },


  /**
   * This function sets the global references to nodes, edges and nodeIndices back to
   * those of the supplied active sector.
   *
   * @param sectorId
   * @private
   */
  _switchToActiveSector : function(sectorId) {
    this.nodeIndices = this.sectors["active"][sectorId]["nodeIndices"];
    this.nodes       = this.sectors["active"][sectorId]["nodes"];
    this.edges       = this.sectors["active"][sectorId]["edges"];
  },


  /**
   * This function sets the global references to nodes, edges and nodeIndices back to
   * those of the supplied frozen sector.
   *
   * @param sectorId
   * @private
   */
  _switchToFrozenSector : function(sectorId) {
    this.nodeIndices = this.sectors["frozen"][sectorId]["nodeIndices"];
    this.nodes       = this.sectors["frozen"][sectorId]["nodes"];
    this.edges       = this.sectors["frozen"][sectorId]["edges"];
  },


  /**
   * This function sets the global references to nodes, edges and nodeIndices to
   * those of the navigation controls sector.
   *
   * @private
   */
  _switchToNavigationSector : function() {
    this.nodeIndices = this.sectors["navigation"]["nodeIndices"];
    this.nodes       = this.sectors["navigation"]["nodes"];
    this.edges       = this.sectors["navigation"]["edges"];
  },


  /**
   * This function sets the global references to nodes, edges and nodeIndices back to
   * those of the currently active sector.
   *
   * @private
   */
  _loadLatestSector : function() {
    this._switchToSector(this._sector());
  },


  /**
   * This function returns the currently active sector Id
   *
   * @returns {String}
   * @private
   */
  _sector : function() {
    return this.activeSector[this.activeSector.length-1];
  },


  /**
   * This function returns the previously active sector Id
   *
   * @returns {String}
   * @private
   */
  _previousSector : function() {
    if (this.activeSector.length > 1) {
      return this.activeSector[this.activeSector.length-2];
    }
    else {
      throw new TypeError('there are not enough sectors in the this.activeSector array.');
    }
  },


  /**
   * We add the active sector at the end of the this.activeSector array
   * This ensures it is the currently active sector returned by _sector() and it reaches the top
   * of the activeSector stack. When we reverse our steps we move from the end to the beginning of this stack.
   *
   * @param newId
   * @private
   */
  _setActiveSector : function(newId) {
    this.activeSector.push(newId);
  },


  /**
   * We remove the currently active sector id from the active sector stack. This happens when
   * we reactivate the previously active sector
   *
   * @private
   */
  _forgetLastSector : function() {
    this.activeSector.pop();
  },


  /**
   * This function creates a new active sector with the supplied newId. This newId
   * is the expanding node id.
   *
   * @param {String} newId   | Id of the new active sector
   * @private
   */
  _createNewSector : function(newId) {
    // create the new sector
    this.sectors["active"][newId] = {"nodes":{},
                                     "edges":{},
                                     "nodeIndices":[],
                                     "formationScale": this.scale,
                                     "drawingNode": undefined};

    // create the new sector render node. This gives visual feedback that you are in a new sector.
    this.sectors["active"][newId]['drawingNode'] = new Node(
        {id:newId,
          color: {
            background: "#eaefef",
            border: "495c5e"
          }
        },{},{},this.constants);
    this.sectors["active"][newId]['drawingNode'].clusterSize = 2;
  },


  /**
   * This function removes the currently active sector. This is called when we create a new
   * active sector.
   *
   * @param {String} sectorId   | Id of the active sector that will be removed
   * @private
   */
  _deleteActiveSector : function(sectorId) {
    delete this.sectors["active"][sectorId];
  },


  /**
   * This function removes the currently active sector. This is called when we reactivate
   * the previously active sector.
   *
   * @param {String} sectorId   | Id of the active sector that will be removed
   * @private
   */
  _deleteFrozenSector : function(sectorId) {
    delete this.sectors["frozen"][sectorId];
  },


  /**
   * Freezing an active sector means moving it from the "active" object to the "frozen" object.
   * We copy the references, then delete the active entree.
   *
   * @param sectorId
   * @private
   */
  _freezeSector : function(sectorId) {
    // we move the set references from the active to the frozen stack.
    this.sectors["frozen"][sectorId] = this.sectors["active"][sectorId];

    // we have moved the sector data into the frozen set, we now remove it from the active set
    this._deleteActiveSector(sectorId);
  },


  /**
   * This is the reverse operation of _freezeSector. Activating means moving the sector from the "frozen"
   * object to the "active" object.
   *
   * @param sectorId
   * @private
   */
  _activateSector : function(sectorId) {
    // we move the set references from the frozen to the active stack.
    this.sectors["active"][sectorId] = this.sectors["frozen"][sectorId];

    // we have moved the sector data into the active set, we now remove it from the frozen stack
    this._deleteFrozenSector(sectorId);
  },


  /**
   * This function merges the data from the currently active sector with a frozen sector. This is used
   * in the process of reverting back to the previously active sector.
   * The data that is placed in the frozen (the previously active) sector is the node that has been removed from it
   * upon the creation of a new active sector.
   *
   * @param sectorId
   * @private
   */
  _mergeThisWithFrozen : function(sectorId) {
    // copy all nodes
    for (var nodeId in this.nodes) {
      if (this.nodes.hasOwnProperty(nodeId)) {
        this.sectors["frozen"][sectorId]["nodes"][nodeId] = this.nodes[nodeId];
      }
    }

    // copy all edges (if not fully clustered, else there are no edges)
    for (var edgeId in this.edges) {
      if (this.edges.hasOwnProperty(edgeId)) {
        this.sectors["frozen"][sectorId]["edges"][edgeId] = this.edges[edgeId];
      }
    }

    // merge the nodeIndices
    for (var i = 0; i < this.nodeIndices.length; i++) {
      this.sectors["frozen"][sectorId]["nodeIndices"].push(this.nodeIndices[i]);
    }
  },


  /**
   * This clusters the sector to one cluster. It was a single cluster before this process started so
   * we revert to that state. The clusterToFit function with a maximum size of 1 node does this.
   *
   * @private
   */
  _collapseThisToSingleCluster : function() {
    this.clusterToFit(1,false);
  },


  /**
   * We create a new active sector from the node that we want to open.
   *
   * @param node
   * @private
   */
  _addSector : function(node) {
    // this is the currently active sector
    var sector = this._sector();

//    // this should allow me to select nodes from a frozen set.
//    if (this.sectors['active'][sector]["nodes"].hasOwnProperty(node.id)) {
//      console.log("the node is part of the active sector");
//    }
//    else {
//      console.log("I dont know what the fuck happened!!");
//    }

    // when we switch to a new sector, we remove the node that will be expanded from the current nodes list.
    delete this.nodes[node.id];

    var unqiueIdentifier = util.randomUUID();

    // we fully freeze the currently active sector
    this._freezeSector(sector);

    // we create a new active sector. This sector has the Id of the node to ensure uniqueness
    this._createNewSector(unqiueIdentifier);

    // we add the active sector to the sectors array to be able to revert these steps later on
    this._setActiveSector(unqiueIdentifier);

    // we redirect the global references to the new sector's references. this._sector() now returns unqiueIdentifier
    this._switchToSector(this._sector());

    // finally we add the node we removed from our previous active sector to the new active sector
    this.nodes[node.id] = node;
  },


  /**
   * We close the sector that is currently open and revert back to the one before.
   * If the active sector is the "default" sector, nothing happens.
   *
   * @private
   */
  _collapseSector : function() {
    // the currently active sector
    var sector = this._sector();

    // we cannot collapse the default sector
    if (sector != "default") {
      if ((this.nodeIndices.length == 1) ||
       (this.sectors["active"][sector]["drawingNode"].width*this.scale < this.constants.clustering.screenSizeThreshold * this.frame.canvas.clientWidth) ||
       (this.sectors["active"][sector]["drawingNode"].height*this.scale < this.constants.clustering.screenSizeThreshold * this.frame.canvas.clientHeight)) {
        var previousSector = this._previousSector();

        // we collapse the sector back to a single cluster
        this._collapseThisToSingleCluster();

        // we move the remaining nodes, edges and nodeIndices to the previous sector.
        // This previous sector is the one we will reactivate
        this._mergeThisWithFrozen(previousSector);

        // the previously active (frozen) sector now has all the data from the currently active sector.
        // we can now delete the active sector.
        this._deleteActiveSector(sector);

        // we activate the previously active (and currently frozen) sector.
        this._activateSector(previousSector);

        // we load the references from the newly active sector into the global references
        this._switchToSector(previousSector);

        // we forget the previously active sector because we reverted to the one before
        this._forgetLastSector();

        // finally, we update the node index list.
        this._updateNodeIndexList();
      }
    }
  },


  /**
   * This runs a function in all active sectors. This is used in _redraw() and the _initializeForceCalculation().
   *
   * @param {String} runFunction  |   This is the NAME of a function we want to call in all active sectors
   *                              |   we dont pass the function itself because then the "this" is the window object
   *                              |   instead of the Graph object
   * @param {*} [argument]            |   Optional: arguments to pass to the runFunction
   * @private
   */
  _doInAllActiveSectors : function(runFunction,argument) {
    if (argument === undefined) {
      for (var sector in this.sectors["active"]) {
        if (this.sectors["active"].hasOwnProperty(sector)) {
          // switch the global references to those of this sector
          this._switchToActiveSector(sector);
          this[runFunction]();
        }
      }
    }
    else {
      for (var sector in this.sectors["active"]) {
        if (this.sectors["active"].hasOwnProperty(sector)) {
          // switch the global references to those of this sector
          this._switchToActiveSector(sector);
          var args = Array.prototype.splice.call(arguments, 1);
          if (args.length > 1) {
            this[runFunction](args[0],args[1]);
          }
          else {
            this[runFunction](argument);
          }
        }
      }
    }
    // we revert the global references back to our active sector
    this._loadLatestSector();
  },


  /**
   * This runs a function in all frozen sectors. This is used in the _redraw().
   *
   * @param {String} runFunction  |   This is the NAME of a function we want to call in all active sectors
   *                              |   we don't pass the function itself because then the "this" is the window object
   *                              |   instead of the Graph object
   * @param {*} [argument]            |   Optional: arguments to pass to the runFunction
   * @private
   */
  _doInAllFrozenSectors : function(runFunction,argument) {
    if (argument === undefined) {
      for (var sector in this.sectors["frozen"]) {
        if (this.sectors["frozen"].hasOwnProperty(sector)) {
          // switch the global references to those of this sector
          this._switchToFrozenSector(sector);
          this[runFunction]();
        }
      }
    }
    else {
      for (var sector in this.sectors["frozen"]) {
        if (this.sectors["frozen"].hasOwnProperty(sector)) {
          // switch the global references to those of this sector
          this._switchToFrozenSector(sector);
          var args = Array.prototype.splice.call(arguments, 1);
          if (args.length > 1) {
            this[runFunction](args[0],args[1]);
          }
          else {
            this[runFunction](argument);
          }
        }
      }
    }
    this._loadLatestSector();
  },


  /**
   * This runs a function in the navigation controls sector.
   *
   * @param {String} runFunction  |   This is the NAME of a function we want to call in all active sectors
   *                              |   we don't pass the function itself because then the "this" is the window object
   *                              |   instead of the Graph object
   * @param {*} [argument]            |   Optional: arguments to pass to the runFunction
   * @private
   */
  _doInNavigationSector : function(runFunction,argument) {
    this._switchToNavigationSector();
    if (argument === undefined) {
      this[runFunction]();
    }
    else {
      var args = Array.prototype.splice.call(arguments, 1);
      if (args.length > 1) {
        this[runFunction](args[0],args[1]);
      }
      else {
        this[runFunction](argument);
      }
    }
    this._loadLatestSector();
  },


  /**
   * This runs a function in all sectors. This is used in the _redraw().
   *
   * @param {String} runFunction  |   This is the NAME of a function we want to call in all active sectors
   *                              |   we don't pass the function itself because then the "this" is the window object
   *                              |   instead of the Graph object
   * @param {*} [argument]        |   Optional: arguments to pass to the runFunction
   * @private
   */
  _doInAllSectors : function(runFunction,argument) {
    var args = Array.prototype.splice.call(arguments, 1);
    if (argument === undefined) {
      this._doInAllActiveSectors(runFunction);
      this._doInAllFrozenSectors(runFunction);
    }
    else {
      if (args.length > 1) {
        this._doInAllActiveSectors(runFunction,args[0],args[1]);
        this._doInAllFrozenSectors(runFunction,args[0],args[1]);
      }
      else {
        this._doInAllActiveSectors(runFunction,argument);
        this._doInAllFrozenSectors(runFunction,argument);
      }
    }

  },


  /**
   * This clears the nodeIndices list. We cannot use this.nodeIndices = [] because we would break the link with the
   * active sector. Thus we clear the nodeIndices in the active sector, then reconnect the this.nodeIndices to it.
   *
   * @private
   */
  _clearNodeIndexList : function() {
    var sector = this._sector();
    this.sectors["active"][sector]["nodeIndices"] = [];
    this.nodeIndices = this.sectors["active"][sector]["nodeIndices"];
  },


  /**
   * Draw the encompassing sector node
   *
   * @param ctx
   * @param sectorType
   * @private
   */
  _drawSectorNodes : function(ctx,sectorType) {
    var minY = 1e9, maxY = -1e9, minX = 1e9, maxX = -1e9, node;
    for (var sector in this.sectors[sectorType]) {
      if (this.sectors[sectorType].hasOwnProperty(sector)) {
        if (this.sectors[sectorType][sector]["drawingNode"] !== undefined) {

          this._switchToSector(sector,sectorType);

          minY = 1e9; maxY = -1e9; minX = 1e9; maxX = -1e9;
          for (var nodeId in this.nodes) {
            if (this.nodes.hasOwnProperty(nodeId)) {
              node = this.nodes[nodeId];
              node.resize(ctx);
              if (minX > node.x - 0.5 * node.width) {minX = node.x - 0.5 * node.width;}
              if (maxX < node.x + 0.5 * node.width) {maxX = node.x + 0.5 * node.width;}
              if (minY > node.y - 0.5 * node.height) {minY = node.y - 0.5 * node.height;}
              if (maxY < node.y + 0.5 * node.height) {maxY = node.y + 0.5 * node.height;}
            }
          }
          node = this.sectors[sectorType][sector]["drawingNode"];
          node.x = 0.5 * (maxX + minX);
          node.y = 0.5 * (maxY + minY);
          node.width = 2 * (node.x - minX);
          node.height = 2 * (node.y - minY);
          node.radius = Math.sqrt(Math.pow(0.5*node.width,2) + Math.pow(0.5*node.height,2));
          node.setScale(this.scale);
          node._drawCircle(ctx);
        }
      }
    }
  },

  _drawAllSectorNodes : function(ctx) {
    this._drawSectorNodes(ctx,"frozen");
    this._drawSectorNodes(ctx,"active");
    this._loadLatestSector();
  }
};