five-bells-visualization/public/bower_components/polymer/src/lib/collection.html

Tool to visualize Five Bells payments

<!--
@license
Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
Code distributed by Google as part of the polymer project is also
subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
-->

<link rel="import" href="array-observe.html">
<link rel="import" href="debounce.html">

<script>

  Polymer._collections = new WeakMap();

  Polymer.Collection = function(userArray, noObserve) {
    Polymer._collections.set(userArray, this);
    this.userArray = userArray;
    this.store = userArray.slice();
    this.callbacks = [];
    this.debounce = null;
    this.map = null;
    this.added = [];
    this.removed = [];
    if (!noObserve) {
      Polymer.ArrayObserve.observe(userArray, this.applySplices.bind(this));
      this.initMap();
    }
  };

  Polymer.Collection.prototype = {
    constructor: Polymer.Collection,

    initMap: function() {
      var map = this.map = new WeakMap();
      var s = this.store;
      var u = this.userArray;
      for (var i=0; i<s.length; i++) {
        var v = s[i];
        if (v) {
          switch (typeof v) {
            case 'string':
              v = s[i] = u[i]= new String(v);
              break;
            case 'number':
              v = s[i] = u[i]= new Number(v);
              break;          
            case 'boolean':
              v = s[i] = u[i]= new Boolean(v);
              break;          
          }
        map.set(v, i);
        }
      }
    },

    add: function(item, squelch) {
      var key = this.store.push(item) - 1;
      if (item != null && this.map) {
        this.map.set(item, key);
      }
      if (!squelch) {
        this.added.push(key);
        this.debounce = Polymer.Debounce(this.debounce, this.notify.bind(this));
      }
      return key;
    },

    removeKey: function(key) {
      if (this.map) {
        this.map.delete(this.store[key]);
      }
      delete this.store[key];
      this.removed.push(key);
      this.debounce = Polymer.Debounce(this.debounce, this.notify.bind(this));
    },

    remove: function(item, squelch) {
      var key = this.getKey(item);
      if (item != null && this.map) {
        this.map.delete(item);
      }
      delete this.store[key];
      if (!squelch) {
        this.removed.push(key);
        this.debounce = Polymer.Debounce(this.debounce, this.notify.bind(this));
      }
      return key;
    },

    notify: function(splices) {
      if (!splices) {
        splices = [{
          added: this.added,
          removed: this.removed
        }];
        this.added = [];
        this.removed = [];
      }
      this.callbacks.forEach(function(cb) {
        cb(splices);
      }, this);
    },

    observe: function(callback) {
      this.callbacks.push(callback);
    },

    unobserve: function(callback) {
      this.callbacks.splice(this.callbacks.indexOf(callback), 1);
    },

    getKey: function(item) {
      if (item != null && this.map) {
        return this.map.get(item);
      } else {
        return this.store.indexOf(item);      
      }
    },

    getKeys: function() {
      return Object.keys(this.store);
    },

    setItem: function(key, value) {
      this.store[key] = value;
    },

    getItem: function(key) {
      return this.store[key];
    },

    getItems: function() {
      var items = [], store = this.store;
      for (var key in store) {
        items.push(store[key]);
      }
      return items;
    },

    applySplices: function(splices) {
      var map = this.map;
      var keySplices = [];
      for (var i=0; i<splices.length; i++) {
        var j, o, key, s = splices[i];
        // Removed keys
        var removed = [];
        for (j=0; j<s.removed.length; j++) {
          o = s.removed[j];
          key = this.remove(o, true);
          removed.push(key);
        }
        // Added keys
        var added = [];
        for (j=0; j<s.addedCount; j++) {
          o = this.userArray[s.index + j];
          key = this.add(o, true);
          added.push(key);
        }
        // Record splice
        keySplices.push({
          index: s.index,
          removed: removed,
          added: added
        });
      }
      this.notify(keySplices);
    }

  };

  Polymer.Collection.get = function(userArray, noObserve) {
    return Polymer._collections.get(userArray) 
      || new Polymer.Collection(userArray, noObserve);
  };

</script>