<!-- The <query2-sk> custom element declaration.

  Starting from a serialized paramtools.ParamSet, this control allows the user
  to build up a query, suitable for passing to query.New.

  Attributes:
    current_query - The current query formatted as a URL formatted query string.

  Events:
    'query-change'
      The 'query2-sk' element will produce 'query-change' events when the query
      parameters chosen have changed. The event contains the current
      selections formatted as a URL query, found in e.detail.q.

    'query-change-delayed'
      The same exact event as query-change, but with a 500ms delay after
      the query stops changing.

  Methods:
    setCurrentQuery(s) - Sets the query selections of the control, where 's'
      is a URL formatted query string, as returned from current_query.

    setParamset(p) -  A serialized paramtools.ParamSet, that is the source
      of the options for the query.

    setKeyOrder(s) - An array of strings, the keys in the order they should
      appear. All keys not in the key order will be present after and in
      alphabetical order.
-->

<link rel="stylesheet" href="/res/common/css/md.css">
<link rel="import" href="/res/imp/bower_components/iron-flex-layout/iron-flex-layout-classes.html">
<link rel="import" href="/res/imp/bower_components/paper-input/paper-input.html">
<link rel="import" href="/res/imp/bower_components/iron-selector/iron-selector.html">

<link rel="import" href="query2-values-sk.html">

<dom-module id="query2-sk">
  <style include="iron-flex iron-flex-alignment iron-positioning">
    input {
      margin: 0 1em;
    }

    iron-selector {
      cursor: pointer;
      border: solid 1px #A6CEE3;
      margin-top: 6px;
      max-height: 600px;
      overflow-y: auto;
    }

    iron-selector div {
      padding: 0.4em 1.2em;
      background-color: white;
      border: none;
      outline: none;
      line-height: 20px;
      vertical-align: middle;
    }

    iron-selector div:hover {
      background-color: #A6CEE3;
    }

    iron-selector div.iron-selected {
      background: #eee;
    }

    iron-selector div.iron-selected:hover {
      background: #1F78B4;
      color: white;
    }

  </style>
  <template>
    <div class="horizontal layout">
      <div class="vertical layout">
        <div class="horizontal layout">
          <paper-input id="fast" label="Filter" on-input="_fastFilter"></paper-input>
          <button on-tap="_clearFilter">Clear Filter</button>
        </div>
        <iron-selector id=keys size=12
          on-selected-items-changed="_keyChange"
          attr-for-selected=value
          >
          <template is="dom-repeat" items="[[_keys]]">
            <div value="[[item]]">[[item]]</div>
          </template>
        </iron-selector>
        <button on-tap="_clear">Clear Selections</button>
      </div>
      <query2-values-sk id=values on-query2-values-changed="_valuesChanged"></query2-values-sk>
    </div>
  </template>
</dom-module>

<script>
  Polymer({
    is: "query2-sk",

    properties: {
      // The serialized form of _query.
      current_query: {
        type: String,
        value: "",
        reflectToAttribute: true,
        notify: true,
        observer: "_currentQueryChanged",
      },

      // A serialized paramtools.ParamSet, which we are building a query around.
      //
      // Might contain a subset of _originalParamset if filtering has been applied.
      _paramset: {
        type: Object,
        value: function() { return {}; },
      },

      // A serialized paramtools.ParamSet, which we are building a query around.
      _originalParamset: {
        type: Object,
        value: function() { return {}; },
      },

      // The keys of paramset.
      _keys: {
        type: Array,
        value: function() { return []; },
      },

      // The currently selected key from _keys.
      _selectedKey: {
        type: String,
        value: "",
      },

      // The current set of user selections.
      _query: {
        type: Object,
        value: function() { return {}; },
      },
      // The order for some or all of the keys. An array of strings.
      _key_order: {
        type: Array,
        value: [],
      },
      _delayedTimeout: {
        type: Number,
        value: null,
      },
    },

    setCurrentQuery: function(s) {
      this._query = sk.query.toParamSet(s);
      this._queryChanged();
    },

    _currentQueryChanged: function(s) {
      this.setCurrentQuery(s)
    },

    setParamset: function(paramset) {
      this._originalParamset = paramset;
      this._paramset = paramset;
      this._recalcKeys();
    },

    setKeyOrder: function(key_order) {
      this._key_order = key_order;
    },

    _recalcKeys: function() {
      var keys = Object.keys(this._paramset);
      keys.sort();
      // Pull out all the keys that appear in _key_order to be pushed
      // to the front of the list, store them in 'pre'.
      var pre = [];
      this._key_order.forEach(function(key) {
        var index = keys.indexOf(key);
        if (index != -1) {
          pre.push(keys.splice(index, 1)[0]);
        }
      }.bind(this));
      keys = pre.concat(keys);

      var key = this.$.keys.selected;

      this.set("_keys", keys);
      this.$.keys.selectedIndex = -1;
      this.$.keys.selected = key;
      this._keyChange();
    },

    _fastFilter: function() {
      var filters = this.$.fast.value.trim().toLowerCase().split(/\s+/);

      // Create a closure that returns true if the given label
      // matches the filter.
      var matches = function(s) {
        s = s.toLowerCase();
        for (var i = 0; i < filters.length; i++) {
          if (s.indexOf(filters[i]) >= 0) {
            return true;
          }
        }
        return false;
      };

      // Loop over this._originalParamset.
      var filtered = {};
      Object.keys(this._originalParamset).forEach(function(paramkey) {
        // If the param key matches, then all the values go over.
        if (matches(paramkey)) {
          filtered[paramkey] = this._originalParamset[paramkey];
        } else {
          // Look for matches in the param values.
          var valueMatches = [];
          this._originalParamset[paramkey].forEach(function(paramvalue) {
            if (matches(paramvalue)) {
              valueMatches.push(paramvalue);
            }
          }.bind(this));
          if (valueMatches.length > 0) {
            filtered[paramkey] = valueMatches;
          }
        }
      }.bind(this));

      this._paramset = filtered;
      this._recalcKeys();
    },

    _clearFilter: function() {
      this._paramset = this._originalParamset;
      this._recalcKeys();
      this.$.fast.value = "";
    },

    _keyChange: function() {
      var key = this.$.keys.selected;
      this.$.values.setOptions(this._paramset[key], this._query[key]);
    },

    _valuesChanged: function(e) {
      var key = this.$.keys.selected;
      this._query[key] = e.detail;
      this._queryChanged();
    },

    _queryChanged: function() {
      var prev_query = this.current_query;
      this.current_query = sk.query.fromParamSet(this._query);
      if (prev_query !== this.current_query) {
        this.dispatchEvent(new CustomEvent('query-change', {
          detail: {q: this.current_query},
          bubbles: true,
        }));
        clearTimeout(this._delayedTimeout);
        this._delayedTimeout = setTimeout(function() {
          this.dispatchEvent(new CustomEvent('query-change-delayed', {
            detail: {q: this.current_query},
            bubbles: true,
          }));
        }.bind(this), 500);
      }
    },

    _clear: function() {
      this._query = {};
      this._recalcKeys();
      this._queryChanged();
    },

  });
</script>