/*!

  \file suggests.js This module contains the Suggests class.

*/

/*!

  Class to handle displaying URL suggestions from history and bookmarks.

*/

function Suggests()

{

    // "Private" member variables

    var suggestsXOffset = 20;

    var inputTimeoutId = null;

    var inputTimeoutDelay = _getTimeoutDelaySetting();

    var maxHeight = 0; // maximum height of suggest list

    var urlSearchHeight = 0;

    var urlSnippetId;

    var urlHasFoucus = false; // URL edit field focus flag

    // Orbit UI has a different URL snippet.

    if (app.layoutType() == "tenone") {

        urlSnippetId = "TitleUrlId";

    }

    else {

        urlSnippetId = "UrlSearchChromeId";

    }

    // "Private" methods

    //! Calculates the maximum height for the suggest list.

    //! If not all suggest items can fit in list, only half an item should be

    //! visible the end when scrolled to the top. This is to indicate more items.

    function _setMaxHeight()

    {

        // Calculate height of available space for suggest list.

        var statusbarSz = snippets.StatusBarChromeId.getGeometry();

        // The Orbit UI doesn't have a status bar.

        var statusbarHeight = (app.ui() == "orbit_ui") ? 0 : statusbarSz.height;

        var urlSearchSz = snippets[urlSnippetId].getGeometry();

        var toolbarSz = snippets.WebViewToolbarId.getGeometry();

        // leave some space between suggest and toolbar (~10% of display height)

        var bufferHeight = Math.ceil(chrome.displaySize.height / 10);

        var availableHeight = chrome.displaySize.height -

            (statusbarHeight + urlSearchSz.height + toolbarSz.height + bufferHeight);

        // Calculate number of elements that can fit in available space.

        var elementHeight = 70; // set in suggests.css

        var numElements = Math.floor(availableHeight / elementHeight);

        // in order to make room for 1/2 entry at end of list we may

        // need to sacrifice 1 full element.

        if ((availableHeight % elementHeight) < (elementHeight / 2)) {

            numElements -= 1;

        }

        numElements += 0.5; // half of final visible entry

        // max suggest list height in pixels

        maxHeight = Math.floor(numElements * elementHeight);

    }

    //! Temporary substitute for settings function to get the delay for

    //! displaying the URL suggests list.

    function _getTimeoutDelaySetting()

    {

        // no setting stored for this currently

        return (1000); // 1 second

    }

    //! Displays and updates suggest list.

    function _showSuggests()

    {

        // make sure the input is the latest

        var input = snippets[urlSnippetId].url;

        // only display suggestions if there is input

        if (input.length != 0) {

            _updateSuggestList(input);

            this.updateSuggestsSize();

            if (!snippets.SuggestsChromeId.visible && pageController.editMode) {

                window.scrollTo(0, 0);

                // Disable the content view, leave the URL serach bar and status bar enabled.

                views.WebView.enabled = false;

                views.WebView.freeze();

                snippets.SuggestsChromeId.show(false);

            }

        } else {

            // no user input so hide suggestions

            _hideSuggests();

        }

    }

    //! Updates the suggestion list based on the specified input.

    /*!

      \param input the current URL box text

    */

    function _updateSuggestList(input)

    {

        var recenturl;

        var recenttitle = window.localeDelegate.translateText(

            "txt_browser_chrome_suggests_search_for");

        var snippetId = document.getElementById('SuggestsId');

        var suggestUL = document.createElement('ul');

        var suggestLI = document.createElement('li');

        var pattern = new RegExp(input, "ig");

        snippetId.innerHTML = ""; // clear previous results

        suggestUL.id = 'suggestUlId';

        suggestLI.id = "searchLiId";

        // always provide an option to search for user entry

        recenttitle = recenttitle.replace(/%1/, "<b>" + input + "</b>");

        suggestLI.innerHTML = '<a href="#" onclick="searchSuggests.searchUrlValue(\''+input+'\');'+

            'return false;">'+

            '<div class="SuggestElement">'+'<span class="aTitle">'+recenttitle+'</span>'+'</div></a>';

        suggestUL.appendChild(suggestLI);

        // add each search suggestion to unordered list

        for (i=0; i < suggests.length; i++) {

            suggestLI = document.createElement('li');

            suggestLI.id = "suggestsLiId";

            // bold search text

            recenttitle = recenttitle.replace(pattern, "<b>$&</b>");

            recenturl = recenturl.replace(pattern, "<b>$&</b>");

                ' return false;">'+

                '<div class="SuggestElement">'+

                '<span class="aTitle">'+recenttitle+'</span><br/>'+

                '<span class="aUrl">'+recenturl+'</span></div></a>';

            suggestUL.appendChild(suggestLI);

        }

        snippetId.appendChild(suggestUL);

    }

    //! Hides suggests list and support items.

    function _hideSuggests()

    {

        clearTimeout(inputTimeoutId);

        window.snippets.SuggestsChromeId.hide(false);

        views.WebView.enabled = true;

        views.WebView.unfreeze();

    }

    // Public Functions

    //! Handler for onload javascript event.

    this.loadComplete = function()

    {

        var urlSearchSz = snippets[urlSnippetId].getGeometry();

        urlSearchHeight = urlSearchSz.height;

        snippets.SuggestsChromeId.anchorTo(urlSnippetId, suggestsXOffset, urlSearchHeight);

        snippets.SuggestsChromeId.zValue = 10;

        _setMaxHeight(); // calculate max suggest list height

        // hide suggests on external mouse events

        snippets.SuggestsChromeId.externalMouseEvent.connect(this.handleExternalMouseEvent);

        // need to resize suggest page snippet on geometry change

        chrome.prepareForGeometryChange.connect(createDelegate(this, this.handleGeometryChange));

    }

    //! Updates the size of the suggests window depending on the size of the

    //! main DIV -- which changes as the number of items changes.

    this.updateSuggestsSize = function()

    {

        if (snippets.SuggestsChromeId != undefined) {

            var totalW = chrome.displaySize.width;

            var divHeight = document.getElementById("SuggestsId").clientHeight + 2;

            var displayHeight = Math.min(maxHeight, divHeight);

            var displayWidth = totalW - (2 * suggestsXOffset);

            // reset snippet height

            snippets.SuggestsChromeId.setSize(displayWidth, displayHeight);

        }

    }

    //! Handles the geometry change signal. Need to re-calculate max height

    //! and then update suggest page height.

    this.handleGeometryChange = function()

    {

        _setMaxHeight(); // max height is based on display height

        this.updateSuggestsSize();

    }

    //! Loads google search page for search string.

    /*!

      \param input value to search for

    */

    this.searchUrlValue = function(input)

    {

        var searchurl = window.pageController.searchUrl(input);

        _hideSuggests();

        window.pageController.currentLoad(searchurl);

        window.pageController.urlTextChanged(searchurl);

    }

    //! Hides suggests list and loads specified page.

    /*!

      \param url address of page to load

    */

    this.gotoUrl = function(url)

    {

        _hideSuggests();

        url = window.pageController.guessUrlFromString(url);

        window.pageController.currentLoad(url);

        window.pageController.urlTextChanged(url);

    }

    //! Handles external mouse events - dismisses suggests list.

    /*!

      \param type the type of event

      \param name the name of event

      \param description event description

    */

    this.handleExternalMouseEvent = function(type, name, description)

    {

        // external mouse event received on VKB mouse clicks and 

        // suggest list mouse clicks both of which should be ignored

        if ((name == "MouseClick") && !urlHasFoucus 

            && !snippets.SuggestsChromeId.hasFocus) {

            _hideSuggests();

        }

    }

    //! Updates the user input for suggestion list.

    /*!

      \param input the current user input

    */

    this.updateUserInput = function()

    {

        // user still editing URL - don't show/update suggests yet

        clearTimeout(inputTimeoutId);

        inputTimeoutId = setTimeout(_showSuggests.bind(this), inputTimeoutDelay);

    }

    //! Called when load state changes. Suggests should only be called when

    //! the load state is editing.

    this.updateLoadState = function()

    {

        if (!pageController.editMode) {

            // not in editing mode - suggests not allowed

            _hideSuggests(); // ensure suggests are hidden

        }

    }

    //! Called when URL search bar focus changes. The external mouse event

    //! handler deals with most cases where the suggestion list should be

    //! dismissed but we don't get those events when the list isn't visible

    //! so this handler is needed to cancel the timer in those cases.

    this.urlSearchFocusChanged = function(focusIn)

    {

        urlHasFoucus = focusIn;

        // if visible user may be scrolling suggestion page so ignore focus change

        if (!focusIn && !snippets.SuggestsChromeId.visible) {

            // prevent suggestion list from being displayed until URL edited again

            clearTimeout(inputTimeoutId);

        }

    }

    //! Sets the user input URL suggest delay.

    /*!

      \param to the new delay time.

    */

    this.setSuggestTimeout = function(to)

    {

        inputTimeoutDelay = to;

    }

}