/*
 * JavaScript functions for the CategoryTree extension, an AJAX based gadget
 * to display the category structure of a wiki
 *
 * @file
 * @ingroup Extensions
 * @author Daniel Kinzler, brightbyte.de
 * @copyright © 2006 Daniel Kinzler
 * @licence GNU General Public Licence 2.0 or later
 *
 * NOTE: if you change this, increment $wgCategoryTreeVersion
 *       in CategoryTree.php to avoid users getting stale copies from cache.
 */

// Default messages if new code loaded with old cached page
var categoryTreeErrorMsg = "Problem loading data.";
var categoryTreeRetryMsg = "Please wait a moment and try again.";

function categoryTreeNextDiv(e) {
	var n= e.nextSibling;
	while ( n && ( n.nodeType != 1 || n.nodeName != 'DIV') ) {
		//alert('nodeType: ' + n.nodeType + '; nodeName: ' + n.nodeName);
		n= n.nextSibling;
	}

	return n;
}

function categoryTreeExpandNode(cat, options, lnk) {
	var div= categoryTreeNextDiv( lnk.parentNode.parentNode );

	div.style.display= 'block';
	lnk.innerHTML= categoryTreeCollapseBulletMsg;
	lnk.title= categoryTreeCollapseMsg;
	lnk.onclick= function() { categoryTreeCollapseNode(cat, options, lnk) }

	if (!lnk.className.match(/(^| )CategoryTreeLoaded($| )/)) {
		categoryTreeLoadNode(cat, options, lnk, div);
	}
}

function categoryTreeCollapseNode(cat, options, lnk) {
	var div= categoryTreeNextDiv( lnk.parentNode.parentNode );

	div.style.display= 'none';
	lnk.innerHTML= categoryTreeExpandBulletMsg;
	lnk.title= categoryTreeExpandMsg;
	lnk.onclick= function() { categoryTreeExpandNode(cat, options, lnk) }
}

function categoryTreeLoadNode(cat, options, lnk, div) {
	div.style.display= 'block';
	lnk.className= 'CategoryTreeLoaded';
	lnk.innerHTML= categoryTreeCollapseBulletMsg;
	lnk.title= categoryTreeCollapseMsg;
	lnk.onclick= function() { categoryTreeCollapseNode(cat, options, lnk) }

	categoryTreeLoadChildren(cat, options, div)
}

// FIXME Why can't this just use uneval()?
function categoryTreeEncodeValue(value) {
	switch (typeof value) {
		case 'function':
			throw new Error("categoryTreeEncodeValue encountered a function");
			break;
		case 'string':
			s = '"' + value.replace(/([\\"'])/g, "\\$1") + '"';
			break;
		case 'number':
		case 'boolean':
		case 'null':
			s = String(value);
			break;
		case 'object':
			if ( !value ) {
				s = 'null';
			} else if (typeof value.length === 'number' && !(value.propertyIsEnumerable('length'))) {
				s = '';
				for (i = 0; i<value.length; i++) {
					v = value[i];
					if ( s!='' ) s += ', ';
					s += categoryTreeEncodeValue( v );
				}
				s = '[' + s + ']';
			} else {
				s = '';
				for (k in value) {
					v = value[k];
					if ( s!='' ) s += ', ';
					s += categoryTreeEncodeValue( k );
					s += ': ';
					s += categoryTreeEncodeValue( v );
				}
				s = '{' + s + '}';
			}
			break;
		default:
			throw new Error("categoryTreeEncodeValue encountered strange variable type " + (typeof value));
	}

	return s;
}

function categoryTreeLoadChildren(cat, options, div) {
	div.innerHTML= '<i class="CategoryTreeNotice">' + categoryTreeLoadingMsg + '</i>';

	if ( typeof options == "string" ) { //hack for backward compatibility
		options = { mode : options };
	}

	function f( request ) {
		if (request.status != 200) {
			div.innerHTML = '<i class="CategoryTreeNotice">' + categoryTreeErrorMsg + ' </i>';
			var retryLink = document.createElement('a');
			retryLink.innerHTML = categoryTreeRetryMsg;
			retryLink.onclick = function() {
				categoryTreeLoadChildren(cat, options, div, enc);
			}
			div.appendChild(retryLink);
			return;
		}

		result= request.responseText;
		result= result.replace(/^\s+|\s+$/, '');

		if ( result == '' ) {
			result= '<i class="CategoryTreeNotice">';

			if ( options.mode == 0 ) {
				result= categoryTreeNoSubcategoriesMsg;
			} else if ( options.mode == 10 ) {
				result= categoryTreeNoPagesMsg;
			} else if ( options.mode == 100 ) {
					result= categoryTreeNoParentCategoriesMsg;
			} else {
				result= categoryTreeNothingFoundMsg;
			}

			result+= '</i>';
		}

		result = result.replace(/##LOAD##/g, categoryTreeExpandMsg);
		div.innerHTML= result;

		categoryTreeShowToggles();
	}

	var opt = categoryTreeEncodeValue(options);
	sajax_do_call( "efCategoryTreeAjaxWrapper", [cat, opt, 'json'] , f );
}

function categoryTreeShowToggles() {
	var toggles = getElementsByClassName( document, 'span', 'CategoryTreeToggle' );

	for( var i = 0; i<toggles.length; ++i ) {
		toggles[i].style.display = 'inline';
	}
}

// Re-show the CategoryTreeToggles
addOnloadHook(categoryTreeShowToggles);