main.js

// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

/*jslint browser: true, es5: true */
/*globals $: true, rootPath: true */

(function() {
    "use strict";
    var resizeTimeout, interval;

    $('.js-only').removeClass('js-only');

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        return params;
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        if (e.keyCode === 188 && $('#help').hasClass('hidden')) { // question mark
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                $('#help').addClass('hidden');
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                e.preventDefault();
                $('#search').addClass('hidden');
                $('#main').removeClass('hidden');
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        document.location.href = url;
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    function initSearch(rawSearchIndex) {
        var currentResults, index, searchIndex;
        var params = getQueryStringParams();

        // Populate search bar with query string search term when provided,
        // but only if the input bar is empty. This avoid the obnoxious issue
        // where you start trying to do a search, and the index loads, and
        // suddenly your search is gone!
        if ($(".search-input")[0].value === "") {
            $(".search-input")[0].value = params.search || '';
        }

        /**
         * Executes the query and builds an index of results
         * @param  {[Object]} query     [The user query]
         * @param  {[type]} max         [The maximum results returned]
         * @param  {[type]} searchWords [The list of search words to query
         *                               against]
         * @return {[type]}             [A search index of results]
         */
        function execQuery(query, max, searchWords) {
            var valLower = query.query.toLowerCase(),
                val = valLower,
                typeFilter = itemTypeFromName(query.type),
                results = [],
                split = valLower.split("::");

            //remove empty keywords
            for (var j = 0; j < split.length; j++) {
                split[j].toLowerCase();
                if (split[j] === "") {
                    split.splice(j, 1);
                }
            }

            // quoted values mean literal search
            var nSearchWords = searchWords.length;
            if ((val.charAt(0) === "\"" || val.charAt(0) === "'") &&
                val.charAt(val.length - 1) === val.charAt(0))
            {
                val = val.substr(1, val.length - 2);
                for (var i = 0; i < nSearchWords; i += 1) {
                    if (searchWords[i] === val) {
                        // filter type: ... queries
                        if (typeFilter < 0 || typeFilter === searchIndex[i].ty) {
                            results.push({id: i, index: -1});
                        }
                    }
                    if (results.length === max) {
                        break;
                    }
                }
            } else {
                // gather matching search results up to a certain maximum
                val = val.replace(/\_/g, "");
                for (var i = 0; i < split.length; i++) {
                    for (var j = 0; j < nSearchWords; j += 1) {
                        if (searchWords[j].indexOf(split[i]) > -1 ||
                            searchWords[j].indexOf(val) > -1 ||
                            searchWords[j].replace(/_/g, "").indexOf(val) > -1)
                        {
                            // filter type: ... queries
                            if (typeFilter < 0 || typeFilter === searchIndex[j].ty) {
                                results.push({id: j, index: searchWords[j].replace(/_/g, "").indexOf(val)});
                            }
                        }
                        if (results.length === max) {
                            break;
                        }
                    }
                }
            }

            var nresults = results.length;
            for (var i = 0; i < nresults; i += 1) {
                results[i].word = searchWords[results[i].id];
                results[i].item = searchIndex[results[i].id] || {};
                results[i].ty = results[i].item.ty;
                results[i].path = results[i].item.path;
            }
            // if there are no results then return to default and fail
            if (results.length === 0) {
                return [];
            }

            // sort by exact match
            results.sort(function search_complete_sort0(aaa, bbb) {
                if (aaa.word === valLower &&
                    bbb.word !== valLower) {
                    return 1;
                }
            });
            // first sorting attempt
            // sort by item name length
            results.sort(function search_complete_sort1(aaa, bbb) {
                if (aaa.word.length > bbb.word.length) {
                    return 1;
                }
            });
            // second sorting attempt
            // sort by item name
            results.sort(function search_complete_sort1(aaa, bbb) {
                if (aaa.word.length === bbb.word.length &&
                    aaa.word > bbb.word) {
                    return 1;
                }
            });
            // third sorting attempt
            // sort by index of keyword in item name
            if (results[0].index !== -1) {
                results.sort(function search_complete_sort1(aaa, bbb) {
                    if (aaa.index > bbb.index && bbb.index === 0) {
                        return 1;
                    }
                });
            }
            // fourth sorting attempt
            // sort by type
            results.sort(function search_complete_sort3(aaa, bbb) {
                if (aaa.word === bbb.word &&
                    aaa.ty > bbb.ty) {
                    return 1;
                }
            });
            // fifth sorting attempt
            // sort by path
            results.sort(function search_complete_sort4(aaa, bbb) {
                if (aaa.word === bbb.word &&
                    aaa.ty === bbb.ty && aaa.path > bbb.path) {
                    return 1;
                }
            });
            // sixth sorting attempt
            // remove duplicates, according to the data provided
            for (var i = results.length - 1; i > 0; i -= 1) {
                if (results[i].word === results[i - 1].word &&
                    results[i].ty === results[i - 1].ty &&
                    results[i].path === results[i - 1].path)
                {
                    results[i].id = -1;
                }
            }
            for (var i = 0; i < results.length; i++) {
                var result = results[i],
                    name = result.item.name.toLowerCase(),
                    path = result.item.path.toLowerCase(),
                    parent = result.item.parent;

                var valid = validateResult(name, path, split, parent);
                if (!valid) {
                    result.id = -1;
                }
            }
            return results;
        }

        /**
         * Validate performs the following boolean logic. For example:
         * "File::open" will give IF A PARENT EXISTS => ("file" && "open")
         * exists in (name || path || parent) OR => ("file" && "open") exists in
         * (name || path )
         *
         * This could be written functionally, but I wanted to minimise
         * functions on stack.
         *
         * @param  {[string]} name   [The name of the result]
         * @param  {[string]} path   [The path of the result]
         * @param  {[string]} keys   [The keys to be used (["file", "open"])]
         * @param  {[object]} parent [The parent of the result]
         * @return {[boolean]}       [Whether the result is valid or not]
         */
        function validateResult(name, path, keys, parent) {
            //initially valid
            var validate = true;
            //if there is a parent, then validate against parent
            if (parent !== undefined) {
                for (var i = 0; i < keys.length; i++) {
                    // if previous keys are valid and current key is in the
                    // path, name or parent
                    if ((validate) &&
                        (name.toLowerCase().indexOf(keys[i]) > -1 ||
                         path.toLowerCase().indexOf(keys[i]) > -1 ||
                         parent.name.toLowerCase().indexOf(keys[i]) > -1))
                    {
                        validate = true;
                    } else {
                        validate = false;
                    }
                }
            } else {
                for (var i = 0; i < keys.length; i++) {
                    // if previous keys are valid and current key is in the
                    // path, name
                    if ((validate) &&
                        (name.toLowerCase().indexOf(keys[i]) > -1 ||
                         path.toLowerCase().indexOf(keys[i]) > -1))
                    {
                        validate = true;
                    } else {
                        validate = false;
                    }
                }
            }
            return validate;
        }

        function getQuery() {
            var matches, type, query = $('.search-input').val();

            matches = query.match(/^(fn|mod|str(uct)?|enum|trait|t(ype)?d(ef)?)\s*:\s*/i);
            if (matches) {
                type = matches[1].replace(/^td$/, 'typedef')
                                 .replace(/^str$/, 'struct')
                                 .replace(/^tdef$/, 'typedef')
                                 .replace(/^typed$/, 'typedef');
                query = query.substring(matches[0].length);
            }

            return {
                query: query,
                type: type,
                id: query + type,
            };
        }

        function initSearchNav() {
            var hoverTimeout, $results = $('.search-results .result');

            $results.on('click', function() {
                var dst = $(this).find('a')[0];
                if (window.location.pathname == dst.pathname) {
                    $('#search').addClass('hidden');
                    $('#main').removeClass('hidden');
                }
                document.location.href = dst.href;
            }).on('mouseover', function() {
                var $el = $(this);
                clearTimeout(hoverTimeout);
                hoverTimeout = setTimeout(function() {
                    $results.removeClass('highlighted');
                    $el.addClass('highlighted');
                }, 20);
            });

            $(document).off('keypress.searchnav');
            $(document).on('keypress.searchnav', function(e) {
                var $active = $results.filter('.highlighted');

                if (e.keyCode === 38) { // up
                    e.preventDefault();
                    if (!$active.length || !$active.prev()) {
                        return;
                    }

                    $active.prev().addClass('highlighted');
                    $active.removeClass('highlighted');
                } else if (e.keyCode === 40) { // down
                    e.preventDefault();
                    if (!$active.length) {
                        $results.first().addClass('highlighted');
                    } else if ($active.next().length) {
                        $active.next().addClass('highlighted');
                        $active.removeClass('highlighted');
                    }
                } else if (e.keyCode === 13) { // return
                    e.preventDefault();
                    if ($active.length) {
                        document.location.href = $active.find('a').prop('href');
                    }
                }
            });
        }

        function showResults(results) {
            var output, shown, query = getQuery();

            currentResults = query.id;
            output = '<h1>Results for ' + query.query +
                    (query.type ? ' (type: ' + query.type + ')' : '') + '</h1>';
            output += '<table class="search-results">';

            if (results.length > 0) {
                shown = [];

                results.forEach(function(item) {
                    var name, type;

                    if (shown.indexOf(item) !== -1) {
                        return;
                    }

                    shown.push(item);
                    name = item.name;
                    type = itemTypes[item.ty];

                    output += '<tr class="' + type + ' result"><td>';

                    if (type === 'mod') {
                        output += item.path +
                            '::<a href="' + rootPath +
                            item.path.replace(/::/g, '/') + '/' +
                            name + '/index.html" class="' +
                            type + '">' + name + '</a>';
                    } else if (type === 'static' || type === 'reexport') {
                        output += item.path +
                            '::<a href="' + rootPath +
                            item.path.replace(/::/g, '/') +
                            '/index.html" class="' + type +
                            '">' + name + '</a>';
                    } else if (item.parent !== undefined) {
                        var myparent = item.parent;
                        var anchor = '#' + type + '.' + name;
                        output += item.path + '::' + myparent.name +
                            '::<a href="' + rootPath +
                            item.path.replace(/::/g, '/') +
                            '/' + itemTypes[myparent.ty] +
                            '.' + myparent.name +
                            '.html' + anchor +
                            '" class="' + type +
                            '">' + name + '</a>';
                    } else {
                        output += item.path +
                            '::<a href="' + rootPath +
                            item.path.replace(/::/g, '/') +
                            '/' + type +
                            '.' + name +
                            '.html" class="' + type +
                            '">' + name + '</a>';
                    }

                    output += '</td><td><span class="desc">' + item.desc +
                        '</span></td></tr>';
                });
            } else {
                output += 'No results :( <a href="https://duckduckgo.com/?q=' +
                    encodeURIComponent('rust ' + query.query) +
                    '">Try on DuckDuckGo?</a>';
            }

            output += "</p>";
            $('#main.content').addClass('hidden');
            $('#search.content').removeClass('hidden').html(output);
            $('#search .desc').width($('#search').width() - 40 -
                $('#search td:first-child').first().width());
            initSearchNav();
        }

        function search(e) {
            var query,
                filterdata = [],
                obj, i, len,
                results = [],
                maxResults = 200,
                resultIndex;
            var params = getQueryStringParams();

            query = getQuery();
            if (e) {
                e.preventDefault();
            }

            if (!query.query || query.id === currentResults) {
                return;
            }

            // Because searching is incremental by character, only the most
            // recent search query is added to the browser history.
            if (browserSupportsHistoryApi()) {
                if (!history.state && !params.search) {
                    history.pushState(query, "", "?search=" +
                                                encodeURIComponent(query.query));
                } else {
                    history.replaceState(query, "", "?search=" +
                                                encodeURIComponent(query.query));
                }
            }

            resultIndex = execQuery(query, 20000, index);
            len = resultIndex.length;
            for (i = 0; i < len; i += 1) {
                if (resultIndex[i].id > -1) {
                    obj = searchIndex[resultIndex[i].id];
                    filterdata.push([obj.name, obj.ty, obj.path, obj.desc]);
                    results.push(obj);
                }
                if (results.length >= maxResults) {
                    break;
                }
            }

            showResults(results);
        }

        // This mapping table should match the discriminants of
        // `rustdoc::html::item_type::ItemType` type in Rust.
        var itemTypes = ["mod",
                         "struct",
                         "enum",
                         "fn",
                         "typedef",
                         "static",
                         "trait",
                         "impl",
                         "viewitem",
                         "tymethod",
                         "method",
                         "structfield",
                         "variant",
                         "ffi",
                         "ffs",
                         "macro"];

        function itemTypeFromName(typename) {
            for (var i = 0; i < itemTypes.length; ++i) {
                if (itemTypes[i] === typename) return i;
            }
            return -1;
        }

        function buildIndex(rawSearchIndex) {
            searchIndex = [];
            var searchWords = [];
            for (var crate in rawSearchIndex) {
                if (!rawSearchIndex.hasOwnProperty(crate)) { continue }

                // an array of [(Number) item type,
                //              (String) name,
                //              (String) full path,
                //              (String) description,
                //              (optional Number) the parent path index to `paths`]
                var items = rawSearchIndex[crate].items;
                // an array of [(Number) item type,
                //              (String) name]
                var paths = rawSearchIndex[crate].paths;

                // convert `paths` into an object form
                var len = paths.length;
                for (var i = 0; i < len; ++i) {
                    paths[i] = {ty: paths[i][0], name: paths[i][1]};
                }

                // convert `items` into an object form, and construct word indices.
                //
                // before any analysis is performed lets gather the search terms to
                // search against apart from the rest of the data.  This is a quick
                // operation that is cached for the life of the page state so that
                // all other search operations have access to this cached data for
                // faster analysis operations
                var len = items.length;
                for (var i = 0; i < len; i += 1) {
                    var rawRow = items[i];
                    var row = {crate: crate, ty: rawRow[0], name: rawRow[1],
                               path: rawRow[2], desc: rawRow[3],
                               parent: paths[rawRow[4]]};
                    searchIndex.push(row);
                    if (typeof row.name === "string") {
                        var word = row.name.toLowerCase();
                        searchWords.push(word);
                    } else {
                        searchWords.push("");
                    }
                }
            }
            return searchWords;
        }

        function startSearch() {
            var keyUpTimeout;
            $('.do-search').on('click', search);
            $('.search-input').on('keyup', function() {
                clearTimeout(keyUpTimeout);
                keyUpTimeout = setTimeout(search, 100);
            });

            // Push and pop states are used to add search results to the browser
            // history.
            if (browserSupportsHistoryApi()) {
                $(window).on('popstate', function(e) {
                    var params = getQueryStringParams();
                    // When browsing back from search results the main page
                    // visibility must be reset.
                    if (!params.search) {
                        $('#main.content').removeClass('hidden');
                        $('#search.content').addClass('hidden');
                    }
                    // When browsing forward to search results the previous
                    // search will be repeated, so the currentResults are
                    // cleared to ensure the search is successful.
                    currentResults = null;
                    // Synchronize search bar with query string state and
                    // perform the search, but don't empty the bar if there's
                    // nothing there.
                    if (params.search !== undefined) {
                        $('.search-input').val(params.search);
                    }
                    // Some browsers fire 'onpopstate' for every page load
                    // (Chrome), while others fire the event only when actually
                    // popping a state (Firefox), which is why search() is
                    // called both here and at the end of the startSearch()
                    // function.
                    search();
                });
            }
            search();
        }

        index = buildIndex(rawSearchIndex);
        startSearch();

        // Draw a convenient sidebar of known crates if we have a listing
        if (rootPath == '../') {
            var sidebar = $('.sidebar');
            var div = $('<div>').attr('class', 'block crate');
            div.append($('<h2>').text('Crates'));

            var crates = [];
            for (var crate in rawSearchIndex) {
                if (!rawSearchIndex.hasOwnProperty(crate)) { continue }
                crates.push(crate);
            }
            crates.sort();
            for (var i = 0; i < crates.length; i++) {
                var klass = 'crate';
                if (crates[i] == window.currentCrate) {
                    klass += ' current';
                }
                div.append($('<a>', {'href': '../' + crates[i] + '/index.html',
                                    'class': klass}).text(crates[i]));
                div.append($('<br>'));
            }
            sidebar.append(div);
        }
    }

    window.initSearch = initSearch;
}());