// +---------------------------------------------------------------------------+
// | This file is part of a Revolution Linux project.                          |
// | Copyright © 2007 Revolution Linux Inc.                                    |
// |                                                                           |
// | For the full copyright and license information, please view the LICENSE   |
// | file that was distributed with this source code.                          |
// +---------------------------------------------------------------------------+

/**
 * RSorter is a class used to sort a given list of data using what I think is
 * the selection sort. I have not yet tested it on very large list but right now
 * it's quite efficient.
 * @package revolution linux
 * @subpackage data
 * @author Jean-Philippe Dery (jeanphilippe.dery@revolutionlinux.com)
 * @copyright Revolution Linux
 * @since 1.0.0
 * @version 1.0.0
 */
var RSorter = RBase.extend(
{
	/**
	 * @var object The selector used to find a single row of data.
	 */
	rowSelector : '',

	/**
	 * @var array The sub selector used to find each sortable fields.
	 */
	txtSelector : null,

	/**
	 * Constructor. Set the row and text selectors and the options. The text
	 * selectors are not mandatory and they can be added manually using the
	 * set column method.
	 * @param string The row selector.
	 * @param object The options.
	 * @return void
	 * @author Jean-Philippe Dery (jeanphilippe.dery@revolutionlinux.com)
	 * @since 1.0.0
	 */
	initialize : function(rowSelector, options) {
		this.rowSelector = rowSelector;
		this.txtSelector = new Array();
		this.options = Object.extend({
			onBegin : null,
			onComplete : null
		}, options || {});
		return this;
	},

	/**
	 * Make a column sortable using the sub selector and an identifier called
	 * a criteria which will be used in the future to start the sorting.
	 * @param string The criteria name.
	 * @param string The column selector.
	 * @return void
	 * @author Jean-Philippe Dery (jeanphilippe.dery@revolutionlinux.com)
	 * @since 1.0.0
	 */
	setColumn : function(criteria, selector) {
		this.txtSelector[criteria] = {selector : selector, mode : 'asc'};
	},

	/**
	 * Return a column data if existent.
	 * @param string The criteria name.
	 * @return object The column selector infos.
	 * @author Jean-Philippe Dery (jeanphilippe.dery@revolutionlinux.com)
	 * @since 1.0.0
	 */
	getColumn : function(criteria) {
		return this.txtSelector[criteria] !== undefined ? this.txtSelector[criteria] : null;
	},

	/**
	 * Sort the list using a given criteria and specify a mode to sort which can
	 * be asc, desc or toggle which switch the last order.
	 * @param string The criteria name.
	 * @param bool True to order the list in descending mode.
	 * @return void
	 * @author Jean-Philippe Dery (jeanphilippe.dery@revolutionlinux.com)
	 * @since 1.0.0
	 */
	sort : function(criteria, mode) {
		var column = this.txtSelector[criteria];
		if (column == null) {
			// somehow we are trying to sort by a non existent field so we stop
			// right here instead of throwing an error
			return;
		}
		mode = mode === undefined ? 'asc' : mode;
		switch (mode.toLowerCase()) {
			case 'asc' : column.mode = 'asc'; break;
			case 'desc' : column.mode = 'desc'; break;
			case 'toggle' : column.mode = column.mode == 'asc' ? 'desc' : 'asc'; break;
		}

		var texts = [];
		var elems = [];
		// the first step consists in creating an array which contains only the
		// texts and the elements so we can work directly on this array
		$ES(this.rowSelector).each(function(elem) {
			elems.push(elem);
			texts.push(elem.getElements(column.selector)[0].getText());
		}.bind(this));
		// now we sort the list and put this list into a new array
		for (var i = 0; i < elems.length; i++) {
			for (var j = i; j < elems.length; j++) {
				if (this.compare(texts[i], texts[j], column.mode == 'desc') == false) {
					texts = this.swap(texts, i, j);
					elems = this.swap(elems, i, j);
				}
			}
		}
		// now all we have to do is rebuild the tree and the list will be
		// correctly sorted
		for (var i = 0; i < elems.length; i++) {
			elems[i].injectAfter(i == 0 ? elems[0] : elems[i - 1]);
		}
	},

	/**
	 * Compare two text value and indicate if the first value is bigger than
	 * the second. The result is inverted if desc is true.
	 * @param string The first value.
	 * @param string The second value.
	 * @param bool True for descending order.
	 * @return bool True if the first value is bigger than the second.
	 * @author Jean-Philippe Dery (jeanphilippe.dery@revolutionlinux.com)
	 * @since 1.0.0
	 */
	compare : function(v1, v2, desc) {
		return (desc) ? v1 > v2 : v1 < v2;
	},

	/**
	 * Switch two elements inside an array and return the new array.
	 * @param array The array.
	 * @param int The first index.
	 * @param int The second index.
	 * @return array The new array.
	 * @author Jean-Philippe Dery (jeanphilippe.dery@revolutionlinux.com)
	 * @since 1.0.0
	 */
	swap : function(arr, i, j) {
		var t = arr[j];
		arr[j] = arr[i];
		arr[i] = t;
		return arr;
	}
});

// ----------- Example

		var sorter = null;
		new RSelector().start({
			'#ambulance-index' : function() {
				// load the sorter object on the list of ambulances and allow a
				// sort by vehicle number, model and permit number
				sorter = new RSorter('#ambulance-index .cards .card');
				sorter.setColumn('vehicle', 'span.vehicle');
				sorter.setColumn('model', 'span.model');
				sorter.setColumn('permit', 'span.permit');
			},
			'#ambulance-index #fe-sort-vehicle:click' : function() { sorter.sort('vehicle') },
			'#ambulance-index #fe-sort-model:click' : function() { sorter.sort('model') },
			'#ambulance-index #fe-sort-permit:click' : function() { sorter.sort('permit') },

		});