//[[he:MediaWiki:Gadget-autocomplete.js]]
//[[ar:MediaWiki:Gadget-autocomplete.js]]
//http://help.wikia.com/wiki/Help:Link_Suggest

mw.loader.using(['jquery.ui', 'jquery.textSelection'], function() {
    //extends jquery with autoCompleteWikiText functionality for autocomplete of links and templates
    $.fn.autoCompleteWikiText = function(options) {
        var mode = "none",
            templateDataCache = {},
            ctrl = $(this),
            settings = $.extend(true, {
            positionMy: "left top" ,
            positionAt: "left bottom" ,
            positionOf: ctrl,
            positionOffset: "0",
            filterResponse: function(a) {
                return a;
            }, // function that expects array of string and returns array of strings
            menuCSS: {
                width: '30%',
                maxHeight: '30em',
                'overflow-y': 'auto'
            },
            itemCSS: {
                right: 'inherit'
            },
            onselected: function(item) {
                var pos = ctrl.textSelection('getCaretPosition') - 1,
                    txt = ctrl.val(),
                	open, close, caretBackwards;

                switch (mode) {
                    case "none":
                        return;
                    case "templateValue":
                        open = "|";
                        close = "";
                        caretBackwards = 0;
                        break;
                    case "templateParams":
                        open = "|";
                        close = "=";
                        caretBackwards = 0;
                        break;
                    case "template":
                        item = item.substr(mw.config.get('wgFormattedNamespaces')[10].length + 1);
                        caretBackwards = 2;
                        open = "((";
                        close = "|))";
                        break;
                    case "link":
                        open = "[[";
                        close = "]]";
                        caretBackwards = 0;
                        if (item[item.length - 1] == ')') item += '|';
                        break;
                }
                var lastbegin = txt.lastIndexOf(open, pos);
                if (txt[lastbegin + 2] == ':')
                    item = ':' + item;

                var newTxt = txt.substr(0, lastbegin) + open + item + close + txt.substr(pos + 1);
                var orgScroll = ctrl.scrollTop();
                ctrl.val(newTxt);
                ctrl.textSelection('setSelection', {
                    start: lastbegin + (open + item + close).length - caretBackwards
                });
                ctrl.scrollTop(orgScroll);
            }
        }, options);

        function findLinks(res) {
            var pos = ctrl.textSelection('getCaretPosition') - 1;
            var txt = ctrl.val();

            var lastbegin = txt.lastIndexOf("[[", pos);
            var lastend = txt.lastIndexOf("]]", pos);
            var isLink = lastbegin > lastend;
            if (isLink) {
                mode = 'link';
                fillLinksList(res, txt.substr(lastbegin + 2, pos - lastbegin));
            } else {
                lastbegin = txt.lastIndexOf("((", pos);
                lastend = txt.lastIndexOf("))", pos);
                var isTemplate = lastbegin > lastend;
                if (isTemplate) {
                    var prefixName = mw.config.get('wgFormattedNamespaces')[10] + ':' + txt.substr(lastbegin + 2, pos - lastbegin - 1);
                    mode = (prefixName.indexOf('|') > -1) ? 'templateParams' : 'template';
                    fillLinksList(res, prefixName);
                } else {
                    mode = "none";
                    res([]);
                }
            }
        }


        function resolveTempalte(templateName) {
            var dfd = new jQuery.Deferred();
            if (!templateName) return dfd.reject().promise();
            if (templateDataCache[templateName]) return dfd.resolve().promise();
            var api = new mw.Api();
            api.get({
                action: 'templatedata',
                titles: templateName,
                redirects: 1
            }).done(function(data) {
                if (!data.pages) return dfd.reject();
                for (var pageid in data.pages) {
                    templateDataCache[templateName] = data.pages[pageid];
                    dfd.resolve();
                }
                if (!templateDataCache[templateName]) dfd.reject();
            });
            return dfd.promise();
        }

        function resolveApi(queryType, queryValue) {
            var dfd = new jQuery.Deferred(),
                api = new mw.Api();

            switch (queryType) {
                case 'users':
                    api.get({
                        action: 'query',
                        list: 'allusers',
                        auactiveusers: 1,
                        auprefix: queryValue
                    }).done(function(data) {
                        if (data && data.query && data.query.allusers) dfd.resolve($.map(data.query.allusers, function(e) {
                            return e.name;
                        }));
                        else dfd.reject();
                    });
                    break;
                case 'pages':
                    api.get({
                        action: 'opensearch',
                        search: queryValue
                    }).done(function(data) {
                        if (data[1]) dfd.resolve(settings.filterResponse(data[1]));
                        else dfd.reject();
                    });
                    break;
                default:
                    throw 'unexpected queryType';
            }

            return dfd.promise();
        }

        function fillLinksList(res, txt) {
            txt = $.trim(txt);
            if (txt.length <= 1 || (mode != 'templateParams' && txt.indexOf('|') > -1) || (txt.indexOf('#') > -1 && mw.config.get('wgNamespaceNumber') === 0)) res([]);
            else if (mode === 'templateParams') {
                var templateMatch = /(.+?)\|(?:.*\|)?([^=]+$)/.exec(txt);
                $.when(resolveTempalte(templateMatch && templateMatch[1])).done(function() {
                    var curTemplateData = templateDataCache[templateMatch[1]],
                    	suggestions = [],
                    	curParamIndex = txt.split('|').length - 1;
                    for (var paramName in curTemplateData.params) {
                        if (paramName == curParamIndex) {
                            var paramValue = templateMatch[2];
                            var dfd;
                            switch (curTemplateData.params[paramName].type) {
                                case 'wiki-page-name':
                                    dfd = $.when(resolveApi('pages', paramValue));
                                    mode = 'templateValue';
                                    break;
                                case 'wiki-file-name':
                                    dfd = $.when(resolveApi('pages', 'File:' + paramValue));
                                    mode = 'templateValue';
                                    break;
                                case 'wiki-template-name':
                                    dfd = $.when(resolveApi('pages', 'Template:' + paramValue));
                                    mode = 'templateValue';
                                    break;                                    
                                case 'wiki-user-name':
                                    dfd = $.when(resolveApi('users', paramValue));
                                    mode = 'templateValue';
                                    break;
                                default:
                                    return res([]); // dont suggest for this indexed param
                            }
                            return dfd.done(res).fail(function() {
                                res([]);
                            });
                        }
                        if (paramName === '1' || txt.indexOf(paramName) > -1) continue; //dont suggest used params
                        suggestions.push(paramName);
                    }
                    res(suggestions);
                }).fail(res);
            } else if (txt.indexOf('#') > -1) {
                var pageTitle = txt.substr(0, txt.indexOf('#'));
                var sectionPrefix = txt.substr(txt.indexOf('#') + 1);
                var api = new mw.Api();
                api.get({
                    action: 'parse',
                    page: pageTitle,
                    prop: 'sections'
                }).done(function(data) {
                    if (data && data.parse && data.parse.sections) res($(data.parse.sections).map(function() {
                        return this.line.indexOf(sectionPrefix) == 0 ? (pageTitle + '#' + this.line.replace(/[|\[\]\{\}]/g, escape)) : null;
                    }));
                });
            } else {
                $.when(resolveApi('pages', txt)).done(res).fail(function() {
                    res([])
                });
            }
        }

        ctrl.autocomplete({
            source: function(request, response) {
                if (fixArrowsBug(this))
                    response([]);
                else
                    findLinks(response);
            },
            focus: function() {
                return false;
            },
            select: function(e, ui) {
                settings.onselected(ui.item.value);
                return false;
            },
            open: function() {
                $(".ui-autocomplete")
                    .css(settings.menuCSS)
                    .position({
                        my: settings.positionMy,
                        at: settings.positionAt,
                        of: settings.positionOf,
                        offset: settings.positionOffset,
                        collision: 'none fit'
                    })
                    .find('li').css(settings.itemCSS);
            }
        });
        var fixed, stfu, escapes = 0;
        //this is hack to prevent known serious bug in autocomplete.js that prevent default of the up and down key which may drive you crazy....
        function fixArrowsBug(self) {
            if (fixed) return false;
            fixed = true;

	   // on click selection may change. close the menu
            ctrl.on("click.autocomplete", function(e){
		clearTimeout(self.searching);
		self.close();
	   });
            ctrl.off("keydown.autocomplete");
            ctrl.off("keydown.autocomplete0");
            ctrl.on("keydown.autocomplete",
                function(event) {
                    var keyCode = $.ui.keyCode;
                    // hack to allow cancelling the gadget: mostly useful when editing templates.
                    escapes = event.keyCode == keyCode.ESCAPE ? escapes + 1 : 0;
                    if ( stfu || ( stfu = escapes >= 3 ) ) {
                        self.close(event);
                    	return;
                    }
                    switch (event.keyCode) {
                        case keyCode.PAGE_UP:
                            self._move("previousPage", event);
                            break;
                        case keyCode.PAGE_DOWN:
                            self._move("nextPage", event);
                            break;
                        case keyCode.UP:
                            if (!self.menu.element.is(":visible")) return;
                            self._move("previous", event);
                            // prevent moving cursor to beginning of text field in some browsers
                            event.preventDefault();
                            break;
                        case keyCode.DOWN:
                            if (!self.menu.element.is(":visible")) return;
                            self._move("next", event);
                            // prevent moving cursor to end of text field in some browsers
                            event.preventDefault();
                            break;
                        case keyCode.ENTER:
                        case keyCode.NUMPAD_ENTER:
                            // when menu is open or has focus
                            if (self.menu.active) {
                                event.preventDefault();
                            }
                            //passthrough - ENTER and TAB both select the current element
                        case keyCode.TAB:
                            if (!self.menu.active) {
                                return;
                            }
                            self.menu.select(event);
                            break;
                        case keyCode.ESCAPE:
                            self.element.val(self.term);
                            self.close(event);
                            break;

                        case keyCode.SHIFT:
                        case keyCode.CONTROL:
                        case keyCode.ALT:
                        case keyCode.COMMAND:
                        case keyCode.COMMAND_RIGHT:
                        case keyCode.INSERT:
                        case keyCode.CAPS_LOCK:
                        case keyCode.END:
                        case keyCode.HOME:
                        case keyCode.LEFT:
                        case keyCode.RIGHT:                        	
                            // ignore metakeys (shift, ctrl, alt)
                            break;
                        default:
                            // keypress is triggered before the input value is changed
                            clearTimeout(self.searching);
                            self.searching = setTimeout(function() {
                                self.search(null, event);
                            }, self.options.delay);
                            break;
                    }
                });
            return true;
        }
    }
});

if ($.inArray(mw.config.get('wgAction'), ['edit', 'submit']) + 1)
    mw.loader.using(['jquery.ui', 'jquery.textSelection'], function() {
        //enable autocomplete for editbox, relative to editform in an offset of -80 vertical
        $("#wpTextbox1").autoCompleteWikiText({
            positionAt: "left top",
            positionOf: '#editform',
            positionOffset: "0 0",
            menuCSS: {
                background: '#E0EEF7',
                opacity: 0.8,
                left: 0
            },
            itemCSS: {
                padding: 0,
                margin: 0
            }
        });
    });