var wpLink;

(function($){

	var inputs = {}, rivers = {}, ed, River, Query;

	wpLink = {

		timeToTriggerRiver: 150,

		minRiverAJAXDuration: 200,

		riverBottomThreshold: 5,

		keySensitivity: 100,

		lastSearch: '',

		textarea: '',

		init : function() {

			inputs.dialog = $('#wp-link');

			inputs.submit = $('#wp-link-submit');

			// URL

			inputs.url = $('#url-field');

			inputs.nonce = $('#_ajax_linking_nonce');

			// Secondary options

			inputs.title = $('#link-title-field');

			// Advanced Options

			inputs.openInNewTab = $('#link-target-checkbox');

			inputs.search = $('#search-field');

			// Build Rivers

			rivers.search = new River( $('#search-results') );

			rivers.recent = new River( $('#most-recent-results') );

			rivers.elements = $('.query-results', inputs.dialog);

			// Bind event handlers

			inputs.dialog.keydown( wpLink.keydown );

			inputs.dialog.keyup( wpLink.keyup );

			inputs.submit.click( function(e){

				e.preventDefault();

				wpLink.update();

			});

			$('#wp-link-cancel').click( function(e){

				e.preventDefault();

				wpLink.close();

			});

			$('#internal-toggle').click( wpLink.toggleInternalLinking );

			rivers.elements.bind('river-select', wpLink.updateFields );

			inputs.search.keyup( wpLink.searchInternalLinks );

			inputs.dialog.bind('wpdialogrefresh', wpLink.refresh);

			inputs.dialog.bind('wpdialogbeforeopen', wpLink.beforeOpen);

			inputs.dialog.bind('wpdialogclose', wpLink.onClose);

		},

		beforeOpen : function() {

			wpLink.range = null;

			if ( ! wpLink.isMCE() && document.selection ) {

				wpLink.textarea.focus();

				wpLink.range = document.selection.createRange();

			}

		},

		open : function() {

			if ( !wpActiveEditor )

				return;

			this.textarea = $('#'+wpActiveEditor).get(0);

			// Initialize the dialog if necessary (html mode).

			if ( ! inputs.dialog.data('wpdialog') ) {

				inputs.dialog.wpdialog({

					title: wpLinkL10n.title,

					width: 480,

					height: 'auto',

					modal: true,

					dialogClass: 'wp-dialog',

					zIndex: 300000

				});

			}

			inputs.dialog.wpdialog('open');

		},

		isMCE : function() {

			return tinyMCEPopup && ( ed = tinyMCEPopup.editor ) && ! ed.isHidden();

		},

		refresh : function() {

			// Refresh rivers (clear links, check visibility)

			rivers.search.refresh();

			rivers.recent.refresh();

			if ( wpLink.isMCE() )

				wpLink.mceRefresh();

			else

				wpLink.setDefaultValues();

			// Focus the URL field and highlight its contents.

			//     If this is moved above the selection changes,

			//     IE will show a flashing cursor over the dialog.

			inputs.url.focus()[0].select();

			// Load the most recent results if this is the first time opening the panel.

			if ( ! rivers.recent.ul.children().length )

				rivers.recent.ajax();

		},

		mceRefresh : function() {

			var e;

			ed = tinyMCEPopup.editor;

			tinyMCEPopup.restoreSelection();

			// If link exists, select proper values.

			if ( e = ed.dom.getParent(ed.selection.getNode(), 'A') ) {

				// Set URL and description.

				inputs.url.val( ed.dom.getAttrib(e, 'href') );

				inputs.title.val( ed.dom.getAttrib(e, 'title') );

				// Set open in new tab.

				if ( "_blank" == ed.dom.getAttrib(e, 'target') )

					inputs.openInNewTab.prop('checked', true);

				// Update save prompt.

				inputs.submit.val( wpLinkL10n.update );

			// If there's no link, set the default values.

			} else {

				wpLink.setDefaultValues();

			}

			tinyMCEPopup.storeSelection();

		},

		close : function() {

			if ( wpLink.isMCE() )

				tinyMCEPopup.close();

			else

				inputs.dialog.wpdialog('close');

		},

		onClose: function() {

			if ( ! wpLink.isMCE() ) {

				wpLink.textarea.focus();

				if ( wpLink.range ) {

					wpLink.range.moveToBookmark( wpLink.range.getBookmark() );

					wpLink.range.select();

				}

			}

		},

		getAttrs : function() {

			return {

				href : inputs.url.val(),

				title : inputs.title.val(),

				target : inputs.openInNewTab.prop('checked') ? '_blank' : ''

			};

		},

		update : function() {

			if ( wpLink.isMCE() )

				wpLink.mceUpdate();

			else

				wpLink.htmlUpdate();

		},

		htmlUpdate : function() {

			var attrs, html, begin, end, cursor,

				textarea = wpLink.textarea;

			if ( ! textarea )

				return;

			attrs = wpLink.getAttrs();

			// If there's no href, return.

			if ( ! attrs.href || attrs.href == 'http://' )

				return;

			// Build HTML

			html = '<a href="' + attrs.href + '"';

			if ( attrs.title )

				html += ' title="' + attrs.title + '"';

			if ( attrs.target )

				html += ' target="' + attrs.target + '"';

			html += '>';

			// Insert HTML

			if ( document.selection && wpLink.range ) {

				// IE

				// Note: If no text is selected, IE will not place the cursor

				//       inside the closing tag.

				textarea.focus();

				wpLink.range.text = html + wpLink.range.text + '</a>';

				wpLink.range.moveToBookmark( wpLink.range.getBookmark() );

				wpLink.range.select();

				wpLink.range = null;

			} else if ( typeof textarea.selectionStart !== 'undefined' ) {

				// W3C

				begin       = textarea.selectionStart;

				end         = textarea.selectionEnd;

				selection   = textarea.value.substring( begin, end );

				html        = html + selection + '</a>';

				cursor      = begin + html.length;

				// If no next is selected, place the cursor inside the closing tag.

				if ( begin == end )

					cursor -= '</a>'.length;

				textarea.value = textarea.value.substring( 0, begin )

				               + html

				               + textarea.value.substring( end, textarea.value.length );

				// Update cursor position

				textarea.selectionStart = textarea.selectionEnd = cursor;

			}

			wpLink.close();

			textarea.focus();

		},

		mceUpdate : function() {

			var ed = tinyMCEPopup.editor,

				attrs = wpLink.getAttrs(),

				e, b;

			tinyMCEPopup.restoreSelection();

			e = ed.dom.getParent(ed.selection.getNode(), 'A');

			// If the values are empty, unlink and return

			if ( ! attrs.href || attrs.href == 'http://' ) {

				if ( e ) {

					tinyMCEPopup.execCommand("mceBeginUndoLevel");

					b = ed.selection.getBookmark();

					ed.dom.remove(e, 1);

					ed.selection.moveToBookmark(b);

					tinyMCEPopup.execCommand("mceEndUndoLevel");

					wpLink.close();

				}

				return;

			}

			tinyMCEPopup.execCommand("mceBeginUndoLevel");

			if (e == null) {

				ed.getDoc().execCommand("unlink", false, null);

				tinyMCEPopup.execCommand("mceInsertLink", false, "#mce_temp_url#", {skip_undo : 1});

				tinymce.each(ed.dom.select("a"), function(n) {

					if (ed.dom.getAttrib(n, 'href') == '#mce_temp_url#') {

						e = n;

						ed.dom.setAttribs(e, attrs);

					}

				});

				// Sometimes WebKit lets a user create a link where

				// they shouldn't be able to. In this case, CreateLink

				// injects "#mce_temp_url#" into their content. Fix it.

				if ( $(e).text() == '#mce_temp_url#' ) {

					ed.dom.remove(e);

					e = null;

				}

			} else {

				ed.dom.setAttribs(e, attrs);

			}

			// Don't move caret if selection was image

			if ( e && (e.childNodes.length != 1 || e.firstChild.nodeName != 'IMG') ) {

				ed.focus();

				ed.selection.select(e);

				ed.selection.collapse(0);

				tinyMCEPopup.storeSelection();

			}

			tinyMCEPopup.execCommand("mceEndUndoLevel");

			wpLink.close();

		},

		updateFields : function( e, li, originalEvent ) {

			inputs.url.val( li.children('.item-permalink').val() );

			inputs.title.val( li.hasClass('no-title') ? '' : li.children('.item-title').text() );

			if ( originalEvent && originalEvent.type == "click" )

				inputs.url.focus();

		},

		setDefaultValues : function() {

			// Set URL and description to defaults.

			// Leave the new tab setting as-is.

			inputs.url.val('http://');

			inputs.title.val('');

			// Update save prompt.

			inputs.submit.val( wpLinkL10n.save );

		},

		searchInternalLinks : function() {

			var t = $(this), waiting,

				search = t.val();

			if ( search.length > 2 ) {

				rivers.recent.hide();

				rivers.search.show();

				// Don't search if the keypress didn't change the title.

				if ( wpLink.lastSearch == search )

					return;

				wpLink.lastSearch = search;

				waiting = t.siblings('img.waiting').show();

				rivers.search.change( search );

				rivers.search.ajax( function(){ waiting.hide(); });

			} else {

				rivers.search.hide();

				rivers.recent.show();

			}

		},

		next : function() {

			rivers.search.next();

			rivers.recent.next();

		},

		prev : function() {

			rivers.search.prev();

			rivers.recent.prev();

		},

		keydown : function( event ) {

			var fn, key = $.ui.keyCode;

			switch( event.which ) {

				case key.UP:

					fn = 'prev';

				case key.DOWN:

					fn = fn || 'next';

					clearInterval( wpLink.keyInterval );

					wpLink[ fn ]();

					wpLink.keyInterval = setInterval( wpLink[ fn ], wpLink.keySensitivity );

					break;

				default:

					return;

			}

			event.preventDefault();

		},

		keyup: function( event ) {

			var key = $.ui.keyCode;

			switch( event.which ) {

				case key.ESCAPE:

					event.stopImmediatePropagation();

					if ( ! $(document).triggerHandler( 'wp_CloseOnEscape', [{ event: event, what: 'wplink', cb: wpLink.close }] ) )

						wpLink.close();

					return false;

					break;

				case key.UP:

				case key.DOWN:

					clearInterval( wpLink.keyInterval );

					break;

				default:

					return;

			}

			event.preventDefault();