Wanikani Ultimate Timeline

Review schedule explorer for WaniKani

このスクリプトの質問や評価の投稿はこちら通報はこちらへお寄せください。
// ==UserScript==
// @name        Wanikani Ultimate Timeline
// @namespace   rfindley
// @description Review schedule explorer for WaniKani
// @version     7.1.8
// @match       https://www.wanikani.com/
// @match       https://www.wanikani.com/dashboard
// @match       https://preview.wanikani.com/
// @match       https://preview.wanikani.com/dashboard
// @copyright   2018-2023, Robin Findley
// @license     MIT; http://opensource.org/licenses/MIT
// @run-at      document-end
// @grant       none
// ==/UserScript==

window.timeline = {};

(function(gobj) {

    /* global $, wkof */
    /* eslint no-multi-spaces: "off" */

    //===================================================================
    // Initialization of the Wanikani Open Framework.
    //-------------------------------------------------------------------
    var script_name = 'Ultimate Timeline';
    var wkof_version_needed = '1.1.3';
    if (!window.wkof) {
        if (confirm(script_name+' requires Wanikani Open Framework.\nDo you want to be forwarded to the installation instructions?')) {
            window.location.href = 'https://community.wanikani.com/t/instructions-installing-wanikani-open-framework/28549';
        }
        return;
    }
    if (wkof.version.compare_to(wkof_version_needed) === 'older') {
        if (confirm(script_name+' requires Wanikani Open Framework version '+wkof_version_needed+'.\nDo you want to be forwarded to the update page?')) {
            window.location.href = 'https://greasyfork.org/en/scripts/38582-wanikani-open-framework';
        }
        return;
    }

    wkof.include('ItemData,Menu,Settings');
    wkof.ready('document,ItemData,Menu,Settings').then(load_settings).then(startup);

    //===================================================================
    // Chart defining the auto-scaling factors of the X-axis.
    //-------------------------------------------------------------------
    var xscale = {
        // Scaling chart.  Each column represents a scaling range,
        // and each row is something that we are scaling.
        hours_per_label:   [  1 ,  3 ,  6 ,  12 ,  24 ,  48 , 720 ],
        red_tic_choices:   ['1d','1d','1d', '1d', '1w','1ws', '1m'], // Red major tics (red label)
        major_tic_choices: ['1h','3h','6h','12h', '1d','1ds', '5D'], // Major tics (has label)
        minor_tic_choices: [ '-','1h','1h', '3h', '6h','12h', '1d'], // Minor tics (no label)
        bundle_choices   : [  1 ,  1 ,  1 ,   3 ,   6 ,  12 ,  24 ], // How many hours are bundled together.
        idx: 0
    };

    //===================================================================
    // Interal global object for centralizing data and configuration.
    //-------------------------------------------------------------------
    var graph = {
        elem: null,
        margin: {
            top: 16,
            left: 28,
            bottom: 16,
        },
        x_axis: {
            width: 0,
            max_hours: 0,
            pixels_per_tic: 0,
        },
        y_axis: {
            height: 100,
            min_height: 80,
            max_height: 300,
            max_reviews: 0,
        },
        radical_cache: {},
    };
    gobj.graph = graph;

    //===================================================================
    // Global utility functions.
    //-------------------------------------------------------------------
    function to_title_case(str) {return str.replace(/\w\S*/g, function(txt){return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();});}

    //===================================================================
    // Global variables
    //-------------------------------------------------------------------
    var settings, settings_dialog;
    var tz_ofs = new Date().getTimezoneOffset();
    var time_shift = Math.ceil(tz_ofs / 60) * 60 - tz_ofs;

    //========================================================================
    // Load the script settings.
    //-------------------------------------------------------------------
    function load_settings() {
        var defaults = {
            minimized: false,
            placement: 'before_nextreview',
            time_format: '12hour',
            graph_height: 100,
            max_days: 14,
            days: 3.5,
            max_bar_width: 40,
            max_bar_height: 0,
            fixed_bar_height: false,
            bar_style: 'item_type',
            srs_curr_next: 'curr',
            current_level_markers: 'rkv',
            burn_markers: 'show',
            show_review_details: 'full',
            review_details_summary: 'item_type',
            review_details_buttons: true,
            show_bar_style_dropdown: true,
        };
        return wkof.Settings.load('timeline', defaults).then(function(data){
            settings = wkof.settings.timeline;
            switch (settings.show_markers) {
                case 'none':
                    settings.current_level_markers = 'none';
                    settings.burn_markers = 'hide';
                    break;
                case 'curr':
                    settings.current_level_markers = 'rkv';
                    settings.burn_markers = 'hide';
                    break;
                case 'burn':
                    settings.current_level_markers = 'none';
                    settings.burn_markers = 'show';
                    break;
                case 'both':
                    settings.current_level_markers = 'rkv';
                    settings.burn_markers = 'show';
                    break;
            }
            delete settings.show_markers;
        });
    }

    //========================================================================
    // Startup
    //-------------------------------------------------------------------
    function startup() {
        install_css();
        install_menu_link();
        place_timeline(true /* first_time */);
        fetch_and_update();
        start_refresh_timer();
    }

    //===================================================================
    // Install a link to the settings in the menu.
    //-------------------------------------------------------------------
    function install_menu_link()
    {
        wkof.Menu.insert_script_link({
            name: 'timeline',
            submenu: 'Settings',
            title: 'Ultimate Timeline',
            on_click: open_settings
        });
    }

    //===================================================================
    // Top-level HTML for the script.
    //-------------------------------------------------------------------
    var timeline_html =
        '<section id="timeline">'+
        '  <h4 class="no_min">Reviews Timeline</h4>'+
        '  <i class="link open noselect no_min fa fa-chevron-up" title="Open the timeline"></i>'+
        '  <i class="link minimize noselect fa fa-chevron-down" title="Minimize the timeline"></i>'+
        '  <i class="link refresh noselect fa fa-refresh" title="Refresh"></i>'+
        '  <i class="link settings noselect fa fa-gear" title="Change timeline settings"></i>'+
        '  <span class="bar_style hidden"><label>Bar Style: </label><select>'+
        '    <option name="count">Review Count</option>'+
        '    <option name="item_type">Item Type</option>'+
        '    <option name="srs_stage">SRS Level</option>'+
        '    <option name="level">Level</option>'+
        '  </select></span>'+
        '  <form class="range_form" class="hidden"><label><span class="range_reviews">0</span> reviews in <span class="range_days">3 days</span> <input class="range_input" type="range" min="0.25" max="7" value="3" step="0.25" name="range_input"></label></form><br clear="all" class="no_min">'+
        '  <div class="graph_wrap">'+
        '    <div class="review_info hidden"><div class="inner"></div></div>'+
        '    <div class="graph_panel"></div>'+
        '  </div>'+
        '</section>';

    //===================================================================
    // Install the style sheet for the script.
    //-------------------------------------------------------------------
    function install_css() {
        var timeline_css =
            '.noselect {-webkit-touch-callout:none; -webkit-user-select:none; -khtml-user-select:none; -moz-user-select:none; -ms-user-select:none; user-select:none; cursor:default;}'+
            '.dashboard section.review-status {border-top: 1px solid #ffffff;}'+
            '.dashboard section.review-status ul li time {white-space: nowrap; overflow-x: hidden; height: 1.5em; margin-bottom: 0;}'+

            '#timeline {margin-bottom: 0px; border-bottom: 1px solid #d4d4d4;}'+
            '#timeline > h4 {clear:none; float:left; height:20px; margin-top:0px; margin-bottom:4px; font-weight:normal; margin-right:12px;}'+
            '@media (max-width: 767px) {#timeline h4 {display: none;}}'+
            '#timeline > .link {color:rgba(0,0,0,0.3); font-size:1.1em; text-decoration:none; cursor:pointer; margin-right:4px;}'+
            '#timeline > .link:hover {color:rgba(255,31,31,0.5);}'+
            '#timeline:not(.min) > .link.open, #timeline.min > :not(.no_min) {display:none;}'+
            '#timeline > .range_form {float:right; margin-bottom:0px; text-align:right;}'+

            '#timeline .bar_style label {display:inline; margin-left:80px;}'+
            '#timeline .bar_style select {height:auto; padding:0; width:auto; vertical-align:baseline; background-color:#e3e3e3; border:1px solid #aaa; border-radius:2px;}'+
            '@media (max-width: 979px) {'+
            '  #timeline .bar_style {float:left; clear:both; margin-left:inherit;}'+
            '  #timeline .bar_style label {margin-left:inherit;}'+
            '}'+
            '@media (max-width: 767px) {#timeline .link {float:left;}}'+

            '#timeline > .graph_panel div, #timeline > .graph_panel canvas {height:100%;width:100%;}'+
            '#timeline > .graph_panel div {border:1px solid #d4d4d4;}'+

            '#timeline .graph_wrap {position:relative;}'+

            '#timeline .review_info {position:absolute; padding-bottom:150px; z-index:5;}'+
            '#timeline .review_info .inner {padding:4px 8px 8px 8px; color:#eeeeee; background-color:rgba(0,0,0,0.8); border-radius:4px; font-weight:bold; z-index:2; box-sizing:border-box;}'+
            '#timeline .review_info .summary {font-family:"Open Sans","Helvetica Neue",Helvetica,Arial,sans-serif; font-size:13px; display:inline-block;}'+
            '#timeline .review_info .summary div {padding:0px 8px;}'+
            '#timeline .review_info .summary .indent {padding:0; margin-bottom:8px;}'+
            '#timeline .review_info .summary .indent:last-child {margin-bottom:0;}'+
            '#timeline .review_info .summary .fixed {text-align:right;}'+
            '#timeline .review_info .summary .tot {color:#000000; background-color:#efefef; background-image:linear-gradient(to bottom, #efefef, #cfcfcf);}'+
            '#timeline .review_info .items_wrap {position:relative;}'+
            '#timeline .summary .fixed {display:inline-block; position:relative;}'+
            '#timeline .review_info .summary .indent>div {display:none}'+

            '#timeline .review_info[data-mode="item_type"] .summary .item_type {display:block;}'+
            '#timeline .review_info[data-mode="srs_stage"] .summary .srs_stage {display:block;}'+
            '#timeline .review_info[data-mode="level"] .summary .level {display:block;}'+

            '#timeline .review_info[data-mode="count"] .item_list > li {background-color:#eee; background-image:linear-gradient(to bottom, #efefef, #cfcfcf); color:#000;}'+
            '#timeline .review_info[data-mode="count"] .item_list > li svg {stroke:#000;}'+
            '#timeline .review_info[data-mode="item_type"] .rad {background-color:#0096e7; background-image:linear-gradient(to bottom, #0af, #0093dd);}'+
            '#timeline .review_info[data-mode="item_type"] .kan {background-color:#ee00a1; background-image:linear-gradient(to bottom, #f0a, #dd0093);}'+
            '#timeline .review_info[data-mode="item_type"] .voc {background-color:#9800e8; background-image:linear-gradient(to bottom, #a0f, #9300dd);}'+
            '#timeline .review_info[data-mode="srs_stage"] .appr {background-color:#dd0093; background-image:linear-gradient(to bottom, #ff00aa, #b30077);}'+
            '#timeline .review_info[data-mode="srs_stage"] .guru {background-color:#882d9e; background-image:linear-gradient(to bottom, #aa38c7, #662277);}'+
            '#timeline .review_info[data-mode="srs_stage"] .mast {background-color:#294ddb; background-image:linear-gradient(to bottom, #516ee1, #2142c4);}'+
            '#timeline .review_info[data-mode="srs_stage"] .enli {background-color:#0093dd; background-image:linear-gradient(to bottom, #00aaff, #0077b3);}'+
            '#timeline .review_info[data-mode="srs_stage"] .burn {background-color:#434343; background-image:linear-gradient(to bottom, #434343, #1a1a1a);}'+
            '#timeline .review_info[data-mode="srs_stage"] li.burn {border:1px solid #777;}'+
            '#timeline .review_info[data-mode="level"] .lvlgrp0 {background-color:#5eb6e8; background-image:linear-gradient(to bottom, #5eb6e8, #1d8ac9);}'+
            '#timeline .review_info[data-mode="level"] .lvlgrp1 {background-color:#e25ebc; background-image:linear-gradient(to bottom, #e25ebc, #c22495);}'+
            '#timeline .review_info[data-mode="level"] .lvlgrp2 {background-color:#af79c3; background-image:linear-gradient(to bottom, #af79c3, #87479e);}'+
            '#timeline .review_info[data-mode="level"] .lvlgrp3 {background-color:#768ce7; background-image:linear-gradient(to bottom, #768ce7, #264ad9);}'+
            '#timeline .review_info[data-mode="level"] .lvlgrp4 {background-color:#5e5e64; background-image:linear-gradient(to bottom, #5e5e64, #313135);}'+
            '#timeline .review_info[data-mode="level"] .lvlgrp5 {background-color:#f5c667; background-image:linear-gradient(to bottom, #f5c667, #f0a50f); color:#333}'+

            '#timeline .review_info[data-mode="level"] .lvlgrp5 svg {stroke:#333}'+

            '#timeline .review_info .summary .indent>.cur {display:block; font-style:italic; color:#000000; background-color:#ffff88; background-image:linear-gradient(to bottom, #ffffaa, #eeee77);}'+
            '#timeline .review_info .summary .indent>.bur {display:block; font-style:italic; color:#ffffff; background-color:#000000; background-image:linear-gradient(to bottom, #444444, #000000);}'+

            '#timeline .item_list {margin: 8px 0 0 0; padding: 0px;}'+
            '#timeline .item_list > li {padding:0 3px; margin:1px 1px; display:inline-block; border-radius:4px; font-size:14px; font-weight:normal; cursor:default; box-sizing:border-box; border:1px solid rgba(0,0,0,0);}'+

            '#timeline[data-detail="full"] .item_list > li {cursor:pointer;}'+
            '#timeline .item_info {position:absolute; background:#333; border:8px solid rgba(0,0,0,0.7); border-radius:6px; left:4px; padding:0 8px; z-index:10;}'+
            '#timeline .item_info .item {font-size:2em; line-height:1.2em;}'+
            '#timeline .review_info wk-character-image {--color-text:#fff;display:inline-block;}'+
            '#timeline .item_list wk-character-image {width:1em; transform:translateY(2px); stroke-width:85;}'+
            '#timeline .item_info .item wk-character-image {width:28px; transform:translateY(2px);}'+

            '#timeline .detail_buttons {display:inline-block; vertical-align:top; margin-left:8px;}'+
            '#timeline .detail_buttons button {display:block; width:130px; padding:0; margin-bottom:2px; color:#000000;}'+

            '#timeline svg {overflow:hidden;}'+
            '#timeline svg .grid {pointer-events:none;}'+
            '#timeline svg .grid path {fill:none;stroke:black;stroke-linecap:square;shape-rendering:crispEdges;}'+
            '#timeline svg .grid .light {stroke:#ffffff;}'+
            '#timeline svg .grid .shadow {stroke:#d5d5d5;}'+
            '#timeline svg .grid .major {opacity:0.15;}'+
            '#timeline svg .grid .minor {opacity:0.05;}'+
            '#timeline svg .grid .redtic {stroke:#f22;opacity:1;}'+
            '#timeline svg .grid .max {stroke:#f22;opacity:0.2;}'+
            '#timeline svg .boundary {fill:#000;opacity:0;}'+
            '#timeline svg .resize_grip {fill:none;cursor:row-resize;}'+
            '#timeline svg .resize_grip .light {stroke:#ffffff;}'+
            '#timeline svg .resize_grip .shadow {stroke:#bbb;}'+
            '#timeline svg text.redtic {fill:#f22;font-weight:bold;}'+
            '#timeline svg .label-x text {text-anchor:start;font-size:0.8em;}'+
            '#timeline svg .label-y text {text-anchor:end;font-size:0.8em;}'+
            '#timeline svg text {pointer-events:none;}'+
            '#timeline svg .bars rect {stroke:none;shape-rendering:crispEdges;}'+
            '#timeline svg .bar.overlay {opacity:0;}'+
            '#timeline svg .bkgd {fill:#f7f7f7;}'+
            '#timeline svg .rad {fill:#00a1f1;}'+
            '#timeline svg .kan {fill:#f100a1;}'+
            '#timeline svg .voc {fill:#a100f1;}'+
            '#timeline svg .sum {fill:#294ddb;}'+
            '#timeline svg .appr {fill:#dd0093;}'+
            '#timeline svg .guru {fill:#882d9e;}'+
            '#timeline svg .mast {fill:#294ddb;}'+
            '#timeline svg .enli {fill:#0093dd;}'+
            '#timeline svg .burn {fill:#434343;}'+
            '#timeline svg .count {fill:#778ad8;}'+
            '#timeline svg .lvlgrp0 {fill:#5eb6e8;}'+
            '#timeline svg .lvlgrp1 {fill:#e25ebc;}'+
            '#timeline svg .lvlgrp2 {fill:#af79c3;}'+
            '#timeline svg .lvlgrp3 {fill:#768ce7;}'+
            '#timeline svg .lvlgrp4 {fill:#5e5e64;}'+
            '#timeline svg .lvlgrp5 {fill:#f5c667;}'+
            '#timeline svg .bars .cur {fill:#ffffff;opacity:0.6;}'+
            '#timeline svg .bars .bur {fill:#000000;opacity:0.4;}'+
            '#timeline svg .markers {stroke:#000000;stroke-width:0.5;}'+
            '#timeline svg .markers .bur {fill:#000000;}'+
            '#timeline svg .markers .cur {fill:#ffffff;}'+
            '#timeline svg .highlight .boundary {cursor:pointer;}'+
            '#timeline[data-detail="none"] .highlight .boundary {cursor:auto;}'+
            '#timeline svg .highlight .marker {pointer-events:none;shape-rendering:crispEdges;}'+
            '#timeline svg .highlight path.marker {fill:#00a1f1; stroke:#00a1f1; stroke-width:2;}'+
            '#timeline svg .highlight rect.marker {fill:rgba(0,161,241,0.1); stroke:#00a1f1; stroke-width:1;}'+
            '#timeline svg.link:hover * {fill:rgb(255,31,31);}'+
            'body.mute_popover .popover.srs {display:none !important;}'+
            '';

        $('head').append('<style>'+timeline_css+'</style>');
    }

    //========================================================================
    // Place the timeline on the dashboard, or adjust its location on the page.
    //-------------------------------------------------------------------
    function place_timeline(first_time) {
        var timeline = (first_time ? $(timeline_html) : $('#timeline'));
        $('.progress-and-forecast').before(timeline);
        if (first_time) {
            // Initialize UI from settings
            graph.elem = timeline.find('.graph_panel');
            graph.x_axis.width = graph.elem.width() - graph.margin.left;
            graph.y_axis.height = settings.graph_height - (graph.margin.top + graph.margin.bottom);
            update_minimize();
            init_ui();

            // Install event handlers
            timeline.find('.link.open, .link.minimize').on('click', toggle_minimize);
            timeline.find('.link.refresh').on('click', fetch_and_update);
            timeline.find('.link.settings').on('click', open_settings);
            timeline.find('.bar_style select').on('change', bar_style_changed);
            timeline.find('.range_input').on('input change', days_changed);
            timeline.find('.review_info>.inner').on('mouseenter', '.item_list > li', item_hover);
            timeline.find('.review_info>.inner').on('mouseleave', '.item_list', item_hover);
            timeline.find('.review_info>.inner').on('click', '.detail_buttons button', detail_button_clicked);
            timeline.find('.review_info>.inner').on('click', function(){return false;});
            window.addEventListener('resize', window_resized);
        }
    }

    //========================================================================
    // Toggle whether the timeline is minimized.
    //-------------------------------------------------------------------
    function toggle_minimize() {
        settings.minimized = !settings.minimized;
        update_minimize();
        save_settings();
    }

    //========================================================================
    // Hide or unhide the timeline when the user minimizes/restores.
    //-------------------------------------------------------------------
    function update_minimize() {
        var timeline = $('#timeline');
        var is_min = timeline.hasClass('min');
        if (settings.minimized && !is_min) {
            timeline.addClass('min');
        } else if (!settings.minimized && is_min) {
            timeline.removeClass('min');
        }
    }

    //========================================================================
    // Update the timeline after the user changes the number of days to display.
    //-------------------------------------------------------------------
    function days_changed() {
        var days = Number($('#timeline .range_input').val());
        if (days === settings.days) return;
        settings.days = days;
        update_slider_days();
        bundle_by_timeslot();
        update_slider_reviews();
        draw_timeline();
        save_settings();
    }

    //========================================================================
    // Handler for when user changes the Bar Style.
    //-------------------------------------------------------------------
    function bar_style_changed() {
        settings.bar_style = $('#timeline .bar_style select :selected').attr('name');
        draw_timeline();
        save_settings();
    }

    //========================================================================
    // Handler for when user clicks 'Save' in the settings window.
    //-------------------------------------------------------------------
    function settings_saved() {
        settings = wkof.settings.timeline;
        place_timeline(false /* first_time */);
        init_ui();
        bundle_by_timeslot();
        draw_timeline();
    }

    //========================================================================
    // Initialize the user interface.
    //-------------------------------------------------------------------
    function init_ui() {
        init_slider();
        if (settings.show_bar_style_dropdown) {
            $('#timeline .bar_style').removeClass('hidden');
        } else {
            $('#timeline .bar_style').addClass('hidden');
        }
        $('#timeline .bar_style option[name="'+settings.bar_style+'"]').prop('selected',true);
        $('#timeline').attr('data-detail', settings.show_review_details);
        $('#timeline .review_info').attr('data-mode', settings.review_details_summary);
    }

    //========================================================================
    // Initialize the scale slider.
    //-------------------------------------------------------------------
    function init_slider() {
        var range = $('#timeline .range_input');
        if (settings.days > settings.max_days) {
            settings.days = settings.max_days;
            save_settings();
        }
        range.attr('max', settings.max_days);
        range.attr('value', settings.days);
        update_slider_days();
    }

    //========================================================================
    // Update the 'reviews' text of the scale slider.
    //-------------------------------------------------------------------
    function update_slider_reviews() {
        var review_count = $('#timeline .range_reviews');
        review_count.text(graph.total_reviews);
    }

    //========================================================================
    // Update the 'days' text of the scale slider.
    //-------------------------------------------------------------------
    function update_slider_days() {
        var days = settings.days;
        var period = $('#timeline .range_days');
        if (days <= 1) {
            period.text((days*24)+' hours');
        } else {
            period.text(days.toFixed(2)+' days');
        }
    }

    //========================================================================
    // Save the script settings (after a 500ms delay).
    //-------------------------------------------------------------------
    var save_delay_timer;
    function save_settings() {
        if (save_delay_timer !== undefined) clearTimeout(save_delay_timer);
        save_delay_timer = setTimeout(function(){
            wkof.Settings.save('timeline');
        }, 500);
    }

    //========================================================================
    // Handler for resizing the panel by dragging the bottom of the graph.
    //------------------------------------------------------------------------
    function resize_panel(e) {
        if (e.button !== 0) return;
        var panel = $('#timeline > .graph_panel');
        var start_y = e.pageY;
        var start_height = settings.graph_height;
        $('body')
        .addClass('mute_popover')
        .on('mousemove.timeline_resize touchmove.timeline_resize', function(e){
            var height = start_height + (e.pageY - start_y);
            if (height < graph.y_axis.min_height) height = graph.y_axis.min_height;
            if (height > graph.y_axis.max_height) height = graph.y_axis.max_height;
            settings.graph_height = height;
            graph.y_axis.height = height - (graph.margin.top + graph.margin.bottom);
            draw_timeline();
        })
        .on('mouseup.timeline_resize touchend.timeline_resize', function(e){
            save_settings();
            $('body').off('.timeline_resize').removeClass('mute_popover');
        });
    }

    //========================================================================
    // Event handler for hovering over the time scale for highlighting.
    //------------------------------------------------------------------------
    var highlight = {start:0, end:0, dragging:false, highlighted: false};
    function highlight_hover(e) {
        if (settings.show_review_details === 'none') return;
        if (highlight.dragging) return true;
        var bundle_idx = nearest_bundle(e.pageX);
        var x;
        switch (e.type) {
            case 'mouseenter':
                break;

            case 'mousemove':
                if (highlight.highlighted) return;
                x = bundle_to_x(bundle_idx);
                $('#timeline .highlight .marker.start').attr('transform', 'translate('+x+',0)');
                break;

            case 'mouseleave':
                if (highlight.dragging || highlight.highlighted) return true;
                hide_highlight();
                break;

            case 'touchstart':
            case 'mousedown':
                if (e.button !== 0) return;
                highlight.highlighted = true;
                highlight.dragging = true;
                highlight.start = bundle_idx;
                x = bundle_to_x(bundle_idx);
                $('#timeline .highlight .marker.start').attr('transform', 'translate('+x+',0)');
                $('#timeline .highlight .marker.end').attr('transform', 'translate(-100,0)');
                $('#timeline .highlight rect.marker').attr('width',0).attr('transform', 'translate('+x+',0)');
                $('body').on('mousemove.timeline_highlight', highlight_drag);
                $('body').on('touchend.timeline_highlight mouseup.timeline_highlight', highlight_release);
                break;
        }
    }

    //========================================================================
    // Even handler for dragging when highlighting a time range.
    //------------------------------------------------------------------------
    function highlight_drag(e) {
        var bundle_idx = nearest_bundle(e.pageX);
        highlight.end = bundle_idx;
        var x1 = bundle_to_x(highlight.start);
        var x2 = bundle_to_x(highlight.end);
        $('#timeline .highlight .marker.end').attr('transform', 'translate('+x2+',0)');
        $('#timeline .highlight rect.marker').attr('transform', 'translate('+Math.min(x1,x2)+'.5,0.5)').attr('width',Math.abs(x2-x1));
        show_review_info(false /* sticky */);
    }

    //========================================================================
    // Event handler for the end of a 'drag' when highlighting a time range.
    //------------------------------------------------------------------------
    function highlight_release(e) {
        if (e.button !== 0) return;
        highlight.dragging = false;
        $('body').off('.timeline_highlight');
        var bundle_idx = nearest_bundle(e.pageX);
        highlight.end = bundle_idx;
        if (highlight.start === highlight.end) {
            hide_highlight();
        } else {
            var x1 = bundle_to_x(Math.min(highlight.start, highlight.end));
            var x2 = bundle_to_x(Math.max(highlight.start, highlight.end));
            $('#timeline .highlight .marker.start').attr('transform', 'translate('+x1+',0)');
            $('#timeline .highlight .marker.end').attr('transform', 'translate('+x2+',0)');
            $('#timeline .highlight rect.marker').attr('transform', 'translate('+x1+'.5,0.5)').attr('width',x2-x1);
            highlight.highlighted = true;
            show_review_info(true /* sticky */);
        }
        return false;
    }

    //========================================================================
    // Hide the timeline's highlight cursors.
    //------------------------------------------------------------------------
    function hide_highlight() {
        highlight.start = -1;
        highlight.end = -1;
        highlight.highlighted = false;
        $('#timeline .highlight rect.marker').attr('width',0).attr('transform', 'translate(-100,0.5)');
        $('#timeline .highlight .marker.start').attr('transform', 'translate(-100,0)');
        $('#timeline .highlight .marker.end').attr('transform', 'translate(-100,0)');
        hide_review_info();
    }

    //========================================================================
    // nearest_bundle()
    //------------------------------------------------------------------------
    function nearest_bundle(x) {
        var panel_left = Math.floor($('#timeline .graph_panel').offset().left);
        x -= panel_left + graph.margin.left;
        if (x < 0) x = 0;
        var tic = x * graph.x_axis.max_hours / graph.x_axis.width;
        var bundle_idx = graph.timeslots[Math.min(graph.x_axis.max_hours-1, Math.floor(tic))];
        var bundle = graph.bundles[bundle_idx];
        var start = bundle.start_time;
        var end = bundle.end_time;
        return (tic <= ((start+end)/2) ? bundle_idx : bundle_idx+1);
    }

    //========================================================================
    // Convert a bundle_idx to a graph hour offset.
    //------------------------------------------------------------------------
    function bundle_to_tic(bundle_idx) {
        if (bundle_idx >= graph.bundles.length) return graph.x_axis.max_hours;
        return graph.bundles[bundle_idx].start_time;
    }

    //========================================================================
    // Convert a bundle_idx to a graph X offset.
    //------------------------------------------------------------------------
    function bundle_to_x(bundle_idx) {
        return Math.round(bundle_to_tic(bundle_idx) * graph.tic_spacing);
    }

    //========================================================================
    // Open the settings dialog
    //-------------------------------------------------------------------
    function open_settings() {
        var config = {
            script_id: 'timeline',
            title: 'Ultimate Timeline',
            on_save: settings_saved,
            content: {
                tabs: {type:'tabset', content: {
                    pgGraph: {type:'page', label:'Graph', hover_tip:'Graph Settings', content: {
                        grpTime: {type:'group', label:'Time', content:{
                            time_format: {type:'dropdown', label:'Time Format', default:'12hour', content:{'12hour':'12-hour','24hour':'24-hour', 'hours_only': 'Hours only'}, hover_tip:'Display time in 12 or 24-hour format, or hours-from-now.'},
                            max_days: {type:'number', label:'Slider Range Max (days)', min:1, max:125, default:7, hover_tip:'Choose maximum range of the timeline slider (in days).'},
                        }},
                        grpBars: {type:'group', label:'Bars', content:{
                            max_bar_width: {type:'number', label:'Max Bar Width (pixels)', default:0, hover_tip:'Set the maximum bar width (in pixels).\n(0 = unlimited)'},
                            max_bar_height: {type:'number', label:'Max Graph Height (reviews)', default:0, hover_tip:'Set the maximum graph height (in reviews).\n(0 = unlimited)\nUseful for when you have a huge backlog.'},
                            fixed_bar_height: {type:'checkbox', label:'Force Graph to Max Height', default:false, hover_tip:'Force the graph height to always be the Max Graph Height.\nUseful when limiting the number of reviews you do in one sitting.'},
                            bar_style: {type:'dropdown', label:'Bar Style', default:'item_type', content:{'count':'Review Count','item_type':'Item Type','srs_stage':'SRS Level','level':'Level'}, hover_tip:'Choose how bars are subdivided.'},
                            srs_curr_next: {type:'dropdown', label:'Current / Next SRS Level', default:'curr', content:{'curr':'Current SRS Level','next':'Next SRS Level'}, hover_tip:'Select whether SRS is color-coded by\ncurrent SRS level, or next SRS level.'},
                        }},
                        grpMarkers: {type:'group', label:'Markers', content:{
                            current_level_markers: {type:'dropdown', label:'Current Level Markers', default:'rkv', content:{'none':'None','rk':'Rad + Kan','rkv':'Rad + Kan + Voc'}, hover_tip:'Select which item types will trigger a Current Level\nmarker at the bottom of the graph.'},
                            burn_markers: {type:'dropdown', label:'Burn Markers', default:'show', content:{'show':'Show','hide':'Hide'}, hover_tip:'Select whether Burn markers are shown\nat the bottom of the graph.'},
                        }},
                    }},
                    pgReviewDetails: {type:'page', label:'Review Details', hover_tip:'Review Details Pop-up', content: {
                        show_review_details: {type:'dropdown', label:'Show Review Details', default:'full', content:{'none':'None','summary':'Summary','item_list':'Item List','full':'Full Item Details'}, hover_tip:'Choose the level of detail to display\nwhen a bar or time range is selected.'},
                        review_details_summary: {type:'dropdown', label:'Review Details Summary', default:'item_type', content:{'count':'Review Count','item_type':'Item Type','srs_stage':'SRS Level','level':'Level'}, hover_tip:'Choose which summary information to\ndisplay on the Review Details pop-up.'},
                        review_details_buttons: {type:'checkbox', label:'Show Review Details Buttons', default:true, hover_tip:'Show configuration buttons on Review Details pop-up.'},
                        show_bar_style_dropdown: {type:'checkbox', label:'Show Bar Style Dropdown', default:false, hover_tip:'Show the Bar Style dropdown above the timeline.'},
                    }},
                }},
            }
        };
        var settings_dialog = new wkof.Settings(config);
        settings_dialog.open();
    }

    //========================================================================
    // Get the number of hours per bar.
    //-------------------------------------------------------------------
    function get_hours_per_bar() {
        graph.x_axis.width = graph.elem.width() - graph.margin.left;
        graph.x_axis.max_hours = Math.round(settings.days * 24);

        // No more than 1 label every 50 pixels
        var min_pixels_per_label = 50;
        graph.min_hours_per_label = min_pixels_per_label * graph.x_axis.max_hours / graph.x_axis.width;
        xscale.idx = 0;
        while ((xscale.hours_per_label[xscale.idx] <= graph.min_hours_per_label) &&
               (xscale.idx < xscale.hours_per_label.length-1)) {
            xscale.idx++;
        }

        return xscale.bundle_choices[xscale.idx];
    }

    //========================================================================
    // Map letters in the xscale chart to corresponding label-generating functions.
    //-------------------------------------------------------------------
    var label_functions = {
        'm': month_label,
        'w': week_label,
        'D': mday_label,
        'd': day_label,
        'h': hour_label,
        '-': no_label,
    };

    //========================================================================
    // Functions for generating time-scale labels
    //-------------------------------------------------------------------
    function month_label(date, qty, use_short) {
        if (date.getHours() !== 0 || date.getDate() !== 1) return;
        return ['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'][date.getMonth()];
    }
    //-------------------------------------------------------------------
    function week_label(date, qty, use_short) {
        if (date.getHours() !== 0 || date.getDay() !== 0) return;
        return (use_short ? 'S' : 'Sun');
    }
    //-------------------------------------------------------------------
    function mday_label(date, qty, use_short) {
        if (date.getHours() !== 0) return;
        var mday = date.getDate();
        if (mday % qty !== 0) return;
        return mday;
    }
    //-------------------------------------------------------------------
    function day_label(date, qty, use_short) {
        if (date.getHours() !== 0) return;
        var label = ['Sun','Mon','Tue','Wed','Thu','Fri','Sat'][date.getDay()];
        return (use_short ? label[0] : label);
    }
    //-------------------------------------------------------------------
    function hour_label(date, qty, use_short) {
        var hh = date.getHours();
        if ((hh % qty) !== 0) return;
        if (settings.time_format === '24hour') {
            return ('0'+hh+':00').slice(-5);
        } else {
            return (((hh + 11) % 12) + 1) + 'ap'[Math.floor(hh/12)] + 'm';
        }
    }
    //-------------------------------------------------------------------
    function hour_only_label(date, qty, use_short, tic_idx) {
        if (tic_idx % qty !== 0) return;
        return tic_idx + (use_short ? 'h' : ' hrs');
    }

    //-------------------------------------------------------------------
    function no_label() {return;}
    //-------------------------------------------------------------------

    //========================================================================
    // Draw the timeline
    //-------------------------------------------------------------------
    function draw_timeline() {
        var panel = graph.elem,
            panel_height = settings.graph_height,
            panel_width = graph.elem.width(),
            graph_height = panel_height - (graph.margin.top + graph.margin.bottom);

        var match = xscale.red_tic_choices[xscale.idx].match(/^(\d*)(.)(s?)$/);
        var red_qty = Number(match[1]);
        var red_func = label_functions[match[2]];
        var red_use_short = (match[3] === 's');

        match = xscale.major_tic_choices[xscale.idx].match(/^(\d*)(.)(s?)$/);
        var maj_qty = Number(match[1]);
        var maj_func = label_functions[match[2]];
        var maj_use_short = (match[3] === 's');

        match = xscale.minor_tic_choices[xscale.idx].match(/^(\d*)(.)(s?)$/);
        var min_qty = Number(match[1]);
        var min_func = label_functions[match[2]];
        var min_use_short = (match[3] === 's');

        if (settings.time_format === 'hours_only') {
            red_func = function() {return 0;};
            maj_func = hour_only_label;
            min_func = hour_only_label;
        }

        var bundle_size = xscale.bundle_choices[xscale.idx];

        // String for building html.
        var grid = '';
        var label_x = [];
        var label_y = '';
        var bars = '', bar_overlays = '';
        var markers = '';

        //=================================
        // Draw vertical axis grid

        // Calculate major and minor vertical graph tics.
        var inc_s = 1, inc_l = 5;
        var max_reviews = graph.max_reviews;
        if (settings.max_bar_height > 0) {
            if (settings.fixed_bar_height || (max_reviews > settings.max_bar_height)) max_reviews = settings.max_bar_height;
        }
        while (Math.ceil(max_reviews / inc_s) > 5) {
            switch (inc_s.toString()[0]) {
                case '1': inc_s *= 2; inc_l *= 2; break;
                case '2': inc_s = Math.round(2.5 * inc_s); break;
                case '5': inc_s *= 2; inc_l *= 5; break;
            }
        }

        // Draw vertical graph tics (# of Reviews).
        var tic_class, y;
        graph.y_axis.max_reviews = Math.max(3, Math.ceil(max_reviews / inc_s) * inc_s);
        for (var tic = 0; tic <= graph.y_axis.max_reviews; tic += inc_s) {
            tic_class = ((tic % inc_l) === 0 ? 'major' : 'minor');
            y = (graph.margin.top + graph_height) - Math.round(graph_height * (tic / graph.y_axis.max_reviews));
            if (tic > 0) {
                grid += '<path class="'+tic_class+'" d="M'+graph.margin.left+','+y+'h'+graph.x_axis.width+'" />';
            }
            label_y += '<text class="'+tic_class+'" x="'+(graph.margin.left-4)+'" y="'+y+'" dy="0.4em">'+tic+'</text>';
        }

        //=================================
        // Draw horizontal axis grid

        graph.tic_spacing = (graph.x_axis.width) / (graph.x_axis.max_hours); // Width of a time slot.
        var prev_label = -9e10;
        for (var tic_idx = 0; tic_idx < graph.x_axis.max_hours; tic_idx++) {
            var time = new Date(graph.start_time.getTime() + tic_idx * 3600000);

            var red_label = red_func(time, red_qty, red_use_short, tic_idx);
            var maj_label = maj_func(time, maj_qty, maj_use_short, tic_idx);
            var min_label = min_func(time, min_qty, min_use_short, tic_idx);

            var x = graph.margin.left + Math.round((tic_idx - time_shift/60) * graph.tic_spacing);
            var label;
            if (red_label) {
                if (tic_idx > 0) grid += '<path class="redtic" d="M'+x+',0v'+(graph.margin.top+graph_height-1)+'" />';
                if (!maj_use_short && tic_idx - prev_label < graph.min_hours_per_label*0.58) label_x.pop();
                label_x.push('<text class="redtic" x="'+(x+4)+'" y="'+(graph.margin.top-8)+'">'+red_label+'</text>');
                prev_label = tic_idx;
            } else if (maj_label) {
                if (tic_idx > 0) grid += '<path class="major" d="M'+x+',0v'+(graph.margin.top+graph_height-1)+'" />';
                if (maj_use_short || tic_idx - prev_label > graph.min_hours_per_label*0.58) {
                    label_x.push('<text class="major" x="'+(x+4)+'" y="'+(graph.margin.top-8)+'">'+maj_label+'</text>');
                    prev_label = tic_idx;
                }
            } else if (min_label) {
                if (tic_idx > 0) grid += '<path class="minor" d="M'+x+','+(graph.margin.top-6)+'v'+(graph_height+6)+'" />';
            }
        }

        //=================================
        // Draw bars

        var min_bar_height = Math.ceil(graph.y_axis.max_reviews / graph.y_axis.height);
        for (var bundle_idx in graph.bundles) {
            var bundle = graph.bundles[bundle_idx];
            var bar_parts = [];
            var stats = bundle.stats;

            var x1 = Math.round(bundle.start_time * graph.tic_spacing);
            var x2 = Math.round(bundle.end_time * graph.tic_spacing);
            if (settings.max_bar_width > 0) x2 = Math.min(x1 + settings.max_bar_width, x2);

            switch (settings.bar_style) {
                case 'count':
                    if (stats.count) bar_parts.push({class:'count', height:stats.count});
                    break;

                case 'item_type':
                    if (stats.rad) bar_parts.push({class:'rad', height:stats.rad});
                    if (stats.kan) bar_parts.push({class:'kan', height:stats.kan});
                    if (stats.voc) bar_parts.push({class:'voc', height:stats.voc});
                    break;

                case 'srs_stage':
                    if (stats.appr) bar_parts.push({class:'appr', height:stats.appr});
                    if (stats.guru) bar_parts.push({class:'guru', height:stats.guru});
                    if (stats.mast) bar_parts.push({class:'mast', height:stats.mast});
                    if (stats.enli) bar_parts.push({class:'enli', height:stats.enli});
                    if (stats.burn) bar_parts.push({class:'burn', height:stats.burn});
                    break;

                case 'level':
                    for (var grp_idx = 0; grp_idx <= 5; grp_idx++) {
                        var grp_name = 'lvlgrp'+grp_idx;
                        if (stats[grp_name]) bar_parts.push({class:'lvlgrp'+grp_idx, height:stats[grp_name]});
                    }
                    break;
            }
            var bar_offset = 0;
            for (var part_idx in bar_parts) {
                var part = bar_parts[part_idx];
                if ((part_idx == bar_parts.length-1) && (bar_offset + part.height < min_bar_height)) {
                    part.height = min_bar_height - bar_offset;
                }
                bars += '<rect class="bar '+part.class+'" x="'+(x1+1)+'" y="'+bar_offset+'" width="'+(x2-x1-3)+'" height="'+part.height+'" />';
                bar_offset += part.height;
            }
            if (bar_parts.length > 0) {
                bar_overlays += '<rect class="bar overlay" x="'+x1+'" y="0" width="'+(x2-x1)+'" height="'+graph.y_axis.max_reviews+'" data-bundle="'+bundle_idx+'" />';
            }

            var marker_x;
            marker_x = graph.margin.left + Math.floor((x1+x2)/2);
            if (bundle.stats.has_curr_marker && settings.current_level_markers !== 'none') {
                markers += '<path class="cur" d="M'+marker_x+','+(graph.margin.top+graph_height+1)+'l-3,6h6z" />';
            }
            if ( bundle.stats.burn_count > 0 && settings.burn_markers === 'show') {
                markers += '<path class="bur" d="M'+marker_x+','+(graph.margin.top+graph_height+8)+'l-3,6h6z" />';
            }
        }

        //=================================
        // Assemble the HTML

        panel.html(
            '<svg class="graph noselect" width="'+panel_width+'" height="'+panel_height+'">'+
            '  <rect class="bkgd" x="'+graph.margin.left+'" y="'+graph.margin.top+'" width="'+graph.x_axis.width+'" height="'+graph_height+'" />'+
            '  <g class="grid" transform="translate(0.5,0.5)">'+
            grid+
            '    <path class="shadow" d="M'+(graph.margin.left-2)+',0v'+(graph.margin.top+graph_height)+',h'+(graph.margin.left+graph.x_axis.width+1)+'" />'+
            '    <path class="light" d="M'+(graph.margin.left-1)+',0v'+(graph.margin.top+graph_height-1)+'" />'+
            '    <path class="light" d="M'+(graph.margin.left-2)+','+(graph.margin.top+graph_height+1)+'h'+(graph.margin.left+graph.x_axis.width+1)+'" />'+
            '  </g>'+
            '  <g class="label-x">'+
            label_x.join('')+
            '  </g>'+
            '  <g class="label-y">'+
            label_y+
            '  </g>'+
            '  <g class="markers" transform="translate(0.5,0.5)">'+
            markers+
            '  </g>'+
            '  <g class="bars" transform="translate('+graph.margin.left+','+(graph.margin.top+graph_height)+') scale(1,'+(-1 * graph_height / graph.y_axis.max_reviews)+')">'+
            bars+
            bar_overlays+
            '  </g>'+
            '  <g class="resize_grip">'+
            '    <path class="shadow" d="M'+(panel_width-2)+','+panel_height+'l2,-2m0,-4l-6,6m-4,0l10,-10" />'+
            '    <path class="light" d="M'+(panel_width-3)+','+panel_height+'l3,-3m0,-4l-7,7m-4,0l11,-11" />'+
            '    <rect class="boundary" x="0" y="'+(panel_height-13)+'" width="'+panel_width+'" height="13" />'+
            '  </g>'+
            '  <g class="highlight">'+
            '    <rect class="marker" transform="translate(-100,0.5)" x="'+graph.margin.left+'" y="'+graph.margin.top+'" width="0" height="'+graph_height+'" />'+
            '    <path class="marker start" transform="translate(-100,0)" d="M'+graph.margin.left+','+(graph.margin.top-1)+'l-3,-5h6l-3,5v'+(graph_height+1)+'" />'+
            '    <path class="marker end" transform="translate(-100,0)" d="M'+graph.margin.left+','+(graph.margin.top-1)+'l-3,-5h6l-3,5v'+(graph_height+1)+'" />'+
            '    <rect class="boundary" x="'+(graph.margin.left-2)+'" y="0" width="'+(graph.x_axis.width+2)+'" height="'+graph.margin.top+'" />'+
            '  </g>'+
            '</svg>'
        );
        panel.height(panel_height);

        // Attach event handlers
        panel.find('.resize_grip .boundary').on('mousedown touchstart', resize_panel);
        panel.find('.highlight .boundary').on('mouseenter mouseleave mousemove mousedown touchstart', highlight_hover);
        panel.find('.bar.overlay').on('mouseenter mouseleave', bar_hover);
        panel.find('.bar.overlay').on('click', bar_click);
    }

    //========================================================================
    // Event handler for clicking timeline bars.
    //-------------------------------------------------------------------
    function bar_click(e) {
        if (settings.show_review_details === 'none') return;
        if (highlight.highlighted) hide_highlight();
        var bundle_idx = Number(e.target.attributes['data-bundle'].value);
        highlight.start = bundle_idx;
        highlight.end = bundle_idx + 1;
        highlight.highlighted = true;
        graph.elem.off('.bar_hover_move');
        show_review_info(true /* sticky */, e);
    }

    //========================================================================
    // Event handler for hovering over timeline bars.
    //-------------------------------------------------------------------
    function bar_hover(e) {
        if (settings.show_review_details === 'none') return;
        if (highlight.highlighted) return;
        switch (e.type) {
            case 'mouseenter':
                var bundle_idx = Number(e.target.attributes['data-bundle'].value);
                highlight.start = bundle_idx;
                highlight.end = bundle_idx + 1;
                show_review_info(false /* sticky */, e);
                graph.elem.on('mousemove.bar_hover_move', function(e){
                    graph.review_info.css('top', e.clientY - e.target.getBoundingClientRect().top - 30);
                });
                break;

            case 'mouseleave':
                graph.elem.off('.bar_hover_move');
                hide_review_info();
                break;
        }
    }

    //========================================================================
    // Build and display the Review Info pop-up.
    //-------------------------------------------------------------------
    function show_review_info(sticky, e) {
        var info = $('#timeline .review_info');
        if (sticky) {
            $('body').off('.timeline_hideinfo');
            setTimeout(function(){
                $('body').on('click.timeline_hideinfo', function(e){
                    $('body').off('.timeline_hideinfo');
                    hide_highlight();
                    hide_review_info();
                });
            }, 10);
        }

        var start = Math.min(highlight.start, highlight.end);
        var end = Math.max(highlight.start, highlight.end);

        var bundle = {items:[]};
        for (var bundle_idx = start; bundle_idx < end; bundle_idx++) {
            bundle.items = bundle.items.concat(graph.bundles[bundle_idx].items);
        }

        calc_bundle_stats(bundle);

        // Print the date or date range.
        var allow_now = ((start === 0) && (graph.bundle_size === 1));
        var html = '<div>';
        var now = new Date();
        var start_date = new Date(graph.start_time.getTime() + bundle_to_tic(start) * 3600000);
        var end_date = new Date(graph.start_time.getTime() + bundle_to_tic(end) * 3600000 + (time_shift - 1) * 60000);
        var same_day = (new Date(start_date).setHours(0,0,0,0) == new Date(end_date).setHours(0,0,0,0));
        var show_month = ((now.getMonth() != start_date.getMonth()) || ((new Date(end_date).setHours(0,0,0,0) - new Date(now).setHours(0,0,0,0)) > (6.5 * 86400000)));
        if (((end-start) > 1) || (graph.bundle_size > 1)) {
            html += format_date(start_date, allow_now, true /* show_day */, show_month) + ' to ' + format_date(end_date, false, !same_day /* show_day */, show_month && !same_day);
        } else {
            html += format_date(start_date, allow_now, true /* show_day */, show_month);
        }
        html += '</div>';

        // Populate item type summaries.
        html += '<div class="summary">';
        html += '<div class="tot">'+(bundle.stats.count)+' reviews</div>';
        html += '<div class="indent">';

        html += '<div class="item_type rad"><span class="fixed">'+(bundle.stats.rad || 0)+'</span> radicals</div>';
        html += '<div class="item_type kan"><span class="fixed">'+(bundle.stats.kan || 0)+'</span> kanji</div>';
        html += '<div class="item_type voc"><span class="fixed">'+(bundle.stats.voc || 0)+'</span> vocabulary</div>';

        html += '<div class="srs_stage appr"><span class="fixed">'+(bundle.stats.appr || 0)+'</span> apprentice</div>';
        html += '<div class="srs_stage guru"><span class="fixed">'+(bundle.stats.guru || 0)+'</span> guru</div>';
        html += '<div class="srs_stage mast"><span class="fixed">'+(bundle.stats.mast || 0)+'</span> master</div>';
        html += '<div class="srs_stage enli"><span class="fixed">'+(bundle.stats.enli || 0)+'</span> enlightened</div>';
        if (settings.srs_curr_next === 'next') {
            html += '<div class="srs_stage burn"><span class="fixed">'+(bundle.stats.burn || 0)+'</span> burn</div>';
        }

        html += '<div class="level lvlgrp0"><span class="fixed">'+(bundle.stats.lvlgrp0 || 0)+'</span> levels 1-10</div>';
        html += '<div class="level lvlgrp1"><span class="fixed">'+(bundle.stats.lvlgrp1 || 0)+'</span> levels 11-20</div>';
        html += '<div class="level lvlgrp2"><span class="fixed">'+(bundle.stats.lvlgrp2 || 0)+'</span> levels 21-30</div>';
        html += '<div class="level lvlgrp3"><span class="fixed">'+(bundle.stats.lvlgrp3 || 0)+'</span> levels 31-40</div>';
        html += '<div class="level lvlgrp4"><span class="fixed">'+(bundle.stats.lvlgrp4 || 0)+'</span> levels 41-50</div>';
        html += '<div class="level lvlgrp5"><span class="fixed">'+(bundle.stats.lvlgrp5 || 0)+'</span> levels 51-60</div>';

        html += '</div>';

        if ((bundle.stats.curr_count > 0) || (bundle.stats.burn_count > 0)) {
            html += '<div class="indent">';
            if (bundle.stats.curr_count > 0) html += '<div class="cur"><span class="fixed">'+bundle.stats.curr_count+'</span> Current Level</div>';
            if (bundle.stats.burn_count > 0) html += '<div class="bur"><span class="fixed">'+bundle.stats.burn_count+'</span> Burn Item'+(bundle.stats.burn_count > 1 ? 's' : '')+'</div>';
            html += '</div>';
        }

        html += '</div>';

        if (settings.review_details_buttons) {
            html += '<div class="detail_buttons">';
            html += '<button class="count">Review Count</button>';
            html += '<button class="item_type">Item Type</button>';
            html += '<button class="srs_stage">SRS Level</button>';
            html += '<button class="level">Level</button>';
            html += '</div>';
        }

        if (settings.show_review_details === 'item_list' || settings.show_review_details === 'full') {
            html = populate_item_list(bundle, html);
        }

        info.find('.inner').html(html);
        graph.review_info = info;

        var num_width = bundle.stats.count.toString();
        info.find('.summary .fixed').css('width', (num_width.toString().length * 9 + 8) + 'px');

        var top, left, right, width;
        var half_width = graph.x_axis.width/2;
        var x = bundle_to_x(start);
        info.css('max-width', half_width);
        if (highlight.dragging) {
            top = graph.margin.top + graph.y_axis.height + graph.margin.bottom;
            if (x < half_width) {
                left = graph.margin.left + x;
                info.css({left:left, right:'auto', top:top});
            } else {
                right = 0;
                info.css({left:'auto', right:right, top:top});
                if (x < graph.x_axis.width - info.outerWidth()) {
                    left = graph.margin.left + x;
                    info.css({left:left, right:'auto', top:top});
                }
            }
        } else if (e) {
            top = e.clientY - e.target.getBoundingClientRect().top - 30;
            if (x < half_width) {
                left = graph.margin.left + bundle_to_x(start+1) + 4;
                info.css({left:left, right:'auto', top:top});
            } else {
                right = graph.x_axis.width - bundle_to_x(start) + 4;
                info.css({left:'auto', right:right, top:top});
            }
        }

        info.removeClass('hidden');
    }

    //========================================================================
    // Populate the list of items present in a time bundle.
    //-------------------------------------------------------------------
    function populate_item_list(bundle, html) {
        var srs_to_class = {
            curr: ['appr','appr','appr','appr','appr','guru','guru','mast','enli'],
            next: ['appr','appr','appr','appr','guru','guru','mast','enli','burn']
        };
        html += '<div class="item_info hidden"></div><ul class="item_list">';
        for (var item_idx in bundle.items) {
            var item = bundle.items[item_idx];
            var classes = [
                (item.object === 'kana_vocabulary' ? 'voc' : item.object.slice(0,3)),
                srs_to_class[settings.srs_curr_next][item.assignments.srs_stage],
                'lvlgrp'+Math.floor((item.data.level-1)/10)
            ];
            var item_name;
            if (item.object === 'radical') {
                if (item.data.characters !== null && item.data.characters !== '') {
                    html += '<li class="'+classes.join(' ')+'">'+item.data.characters+'</li>';
                } else {
                    html += '<li class="'+classes.join(' ')+'" data-radname="'+item.data.slug+'">';
                    var url = item.data.character_images.filter(function(img){
                        return (img.content_type === 'image/svg+xml' && img.metadata.inline_styles);
                    })[0]?.url;
                    if (!url) {
                        html += '??';
                    } else {
                        html += '<wk-character-image src="'+url+'"></wk-character-image>';
                    }
                    html += '</li>';
                }
            } else {
                html += '<li class="'+classes.join(' ')+'">'+item.data.slug+'</li>';
            }
        }
        html += '</ul>';
        return html;
    }

    //========================================================================
    // Insert an svg into a specified DOM element.
    //-------------------------------------------------------------------
    function populate_radical_svg(selector, svg) {
        $(selector).html(svg);
        $(selector+' svg').addClass('radical');
    }

    //========================================================================
    // Event handler for buttons on the Review Info pop-up.
    //-------------------------------------------------------------------
    function detail_button_clicked(e) {
        var mode = e.target.className;
        $('#timeline .review_info').attr('data-mode', mode);
        settings.review_details_summary = mode;
        save_settings();
    }

    //========================================================================
    // Event handler for hovering over an item in the Review Detail pop-up.
    //-------------------------------------------------------------------
    function item_hover(e) {
        if (settings.show_review_details !== 'full') return;
        var info = $('#timeline .item_info');
        switch (e.type) {
            case 'mouseenter':
                var target = $(e.currentTarget);
                var item = graph.current_bundle.items[target.index()];
                var pos = target.position();
                info.css({top:pos.top+target.outerHeight()+3});
                populate_item_info(info, item);
                info.removeClass('hidden');
                break;

            case 'mouseleave':
                info.addClass('hidden');
                break;
        }
    }

    //========================================================================
    // Handler for resizing the timeline when the window size changes.
    //-------------------------------------------------------------------
    function window_resized() {
        var new_width = graph.elem.width();
        if (new_width != graph.x_axis.width + graph.margin.left) {
            bundle_by_timeslot();
            draw_timeline();
        }
    }

    //========================================================================
    // Generate the HTML content of the Item Detail pop-up.
    //-------------------------------------------------------------------
    var srs_stages = ['Initiate', 'Apprentice 1', 'Apprentice 2', 'Apprentice 3', 'Apprentice 4', 'Guru 1', 'Guru 2', 'Master', 'Enlightened', 'Burned']
    function populate_item_info(info, item) {
        var html;
        switch (item.object) {
            case 'radical':
                if (item.data.characters !== null && item.data.characters !== '') {
                    html = '<span class="item">Radical: <span class="slug" lang="ja">'+item.data.characters+'</span></span><br>';
                } else {
                    html = '<span class="item">Radical: <span class="slug" data-radname="'+item.data.slug+'">';
                    var url = item.data.character_images.filter(function(img){
                        return (img.content_type === 'image/svg+xml' && img.metadata.inline_styles);
                    })[0]?.url;
                    if (!url) {
                        html += '??';
                    } else {
                        html += '<wk-character-image src="'+url+'"></wk-character-image>';
                    }
                    html += '</span></span><br>';
                }
                break;

            case 'kanji':
                html = '<span class="item">Kanji: <span class="slug" lang="ja">'+item.data.slug+'</span></span><br>';
                html += get_important_reading(item)+'<br>';
                break;

            case 'vocabulary':
                html = '<span class="item">Vocab: <span class="slug" lang="ja">'+item.data.slug+'</span></span><br>';
                html += 'Reading: '+get_reading(item)+'<br>';
                break;

            case 'kana_vocabulary':
                html = '<span class="item">Vocab: <span class="slug" lang="ja">'+item.data.slug+'</span></span><br>';
                break;
        }
        html += 'Meaning: '+get_meanings(item)+'<br>';
        html += 'Level: '+item.data.level+'<br>';
        html += 'SRS Level: '+item.assignments.srs_stage+' ('+srs_stages[item.assignments.srs_stage]+')';
        info.html(html);
    }

    //========================================================================
    // Load a radical's svg file.
    //-------------------------------------------------------------------
    function load_radical_svg(item) {
        var promise = graph.radical_cache[item.data.slug];
        if (promise) return promise;
        if (item.data.character_images.length === 0) return promise;
        var url = item.data.character_images.filter(function(img){
            return (img.content_type === 'image/svg+xml' && img.metadata.inline_styles);
        })[0]?.url;
        promise = wkof.load_file(url);
        graph.radical_cache[item.data.slug] = promise;
        return promise;
    }

    //========================================================================
    // Extract the meanings (including synonyms) from an item.
    //-------------------------------------------------------------------
    function get_meanings(item) {
        var meanings = [];
        if (item.study_materials && item.study_materials.meaning_synonyms) {
            meanings = item.study_materials.meaning_synonyms;
        }
        meanings = meanings.concat(item.data.meanings.map(meaning => meaning.meaning));
        return to_title_case(meanings.join(', '));
    }

    //========================================================================
    // Extract the 'important' readings from a kanji.
    //-------------------------------------------------------------------
    function get_important_reading(item) {
        var readings = item.data.readings.filter(reading => reading.primary);
        return to_title_case(readings[0].type)+': '+readings.map(reading => reading.reading).join(', ');
    }

    //========================================================================
    // Extract the list of readings from an item.
    //-------------------------------------------------------------------
    function get_reading(item) {
        return item.data.readings.map(reading => reading.reading).join(', ');
    }

    //========================================================================
    // Hide the Review Info pop-up.
    //-------------------------------------------------------------------
    function hide_review_info() {
        $('#timeline .review_info').addClass('hidden');
    }

    //========================================================================
    // Generate a formatted date string.
    //-------------------------------------------------------------------
    function format_date(time, allow_now, show_day, show_month) {
        var str = '';
        if (allow_now && time.getTime() >= graph.start_time.getTime()) return 'Now';
        if (show_day) {
            if (new Date(time).setHours(0,0,0,0) === (new Date()).setHours(0,0,0,0)) {
                str = 'Today';
                show_month = false;
            } else {
                str = 'SunMonTueWedThuFriSat'.substr(time.getDay()*3, 3);
            }
            if (show_month) {
                str += ', ' + 'JanFebMarAprMayJunJulAugSepOctNovDec'.substr(time.getMonth()*3, 3) + ' ' + time.getDate();
            }
        }
        if (settings.time_format === '24hour') {
            str += ' ' + ('0' + time.getHours()).slice(-2) + ':' + ('0'+time.getMinutes()).slice(-2);
        } else {
            str += ' ' + ('0' + (((time.getHours()+11)%12)+1)).slice(-2) + ':'+('0'+time.getMinutes()).slice(-2) + 'ap'[Math.floor(time.getHours()/12)] + 'm';
        }
        return str;
    }

    //========================================================================
    // Fetch item info, and redraw the timeline.
    //-------------------------------------------------------------------
    function fetch_and_update() {
        return wkof.ItemData.get_items('subjects, assignments, study_materials')
        .then(process_items)
        .then(draw_timeline);
    }

    //========================================================================
    // Process the fetched items.
    //-------------------------------------------------------------------
    function process_items(fetched_items) {
        // Remove any unlearned items.
        graph.items = [];
        for (var idx in fetched_items) {
            var item = fetched_items[idx];
            if (!item.assignments || !item.assignments.available_at || item.assignments.srs_stage <= 0) continue;
            graph.items.push(item);
        }

        graph.items.sort(function(a, b) {
            return (new Date(a.assignments.available_at).getTime() - new Date(b.assignments.available_at).getTime());
        });

        bundle_by_timeslot();
        update_slider_reviews();
    }

    //========================================================================
    // Bundle the items into timeslots.
    //-------------------------------------------------------------------
    function bundle_by_timeslot() {
        var bundle_size = graph.bundle_size = get_hours_per_bar();
        var bundles = graph.bundles = [];
        var timeslots = graph.timeslots = [];

        // Rewind the clock to the start of a bundle period.
        var start_time = toStartOfUTCHour(new Date());
        while (start_time.getHours() % bundle_size !== 0) start_time = new Date(start_time.getTime() - 3600000);
        graph.start_time = start_time;

        // Find the tic of the last bundle (round down if only a partial).
        graph.total_reviews = 0;
        graph.max_reviews = 0;
        var hour = 0, item_idx = 0, item_count = 0;
        var bundle = {start_time:hour, items:[]};
        while (true) {
            timeslots.push(bundles.length);
            hour++;
            // Check if we're past end of the timeline (including rounding up to the nearest bundle)
            // Need to use date function to account for time shifts (e.g. Daylight Savings Time)
            var time = new Date(start_time.getTime() + hour * 3600000);
            if ((time.getHours() % bundle_size) !== 0) continue;

            var start_idx = item_idx;
            while ((item_idx < graph.items.length) &&
                   (new Date(graph.items[item_idx].assignments.available_at) < time)) {
                item_idx++;
            }

            bundle.items = graph.items.slice(start_idx, item_idx);
            bundle.end_time = hour;
            calc_bundle_stats(bundle);
            graph.bundles.push(bundle);

            graph.total_reviews += bundle.items.length;
            if (bundle.items.length > graph.max_reviews) graph.max_reviews = bundle.items.length;
            if (hour >= graph.x_axis.max_hours) break;

            bundle = {start_time:hour, items:[]};
        }
        graph.x_axis.max_hours = hour;
    }

    //========================================================================
    // Calculate stats for a bundle
    //-------------------------------------------------------------------
    function calc_bundle_stats(bundle) {
        var itype_to_int = {radical:0, kanji:1, vocabulary:2};
        var itype_to_class = {radical:'rad', kanji:'kan', vocabulary:'voc', kana_vocabulary:'voc'};
        var srs_to_class = {
            curr: ['appr','appr','appr','appr','appr','guru','guru','mast','enli'],
            next: ['appr','appr','appr','appr','guru','guru','mast','enli','burn']
        };
        bundle.items.sort(function(a, b){
            var a_itype = itype_to_int[a.object];
            var b_itype = itype_to_int[b.object];
            if (a_itype !== b_itype) return a_itype - b_itype;
            if (a.data.level !== b.data.level) return a.data.level - b.data.level;
            return a.data.slug.localeCompare(b.data.slug);
        });
        bundle.stats = {
            count:0,
            rad:0, kan:0, voc:0,
            appr:0, guru:0, mast:0, enli:0, burn:0,
            lvlgrp0:0, lvlgrp1:0, lvlgrp2:0, lvlgrp3:0, lvlgrp4:0, lvlgrp5:0,
            curr_count: 0,
            has_curr_marker: false,
            burn_count: 0
        };
        var stats = bundle.stats;
        for (var item_idx in bundle.items) {
            var item = bundle.items[item_idx];
            stats.count++;
            stats[itype_to_class[item.object]]++;
            stats[srs_to_class[settings.srs_curr_next][item.assignments.srs_stage]]++;
            stats['lvlgrp'+Math.floor((item.data.level-1)/10)]++;
            if (item.data.level === wkof.user.level) {
                stats.curr_count++;
                if (settings.current_level_markers.indexOf(itype_to_class[item.object][0]) >= 0) {
                    stats.has_curr_marker = true;
                }
            }
        }
        bundle.stats.burn_count = bundle.stats[srs_to_class[settings.srs_curr_next][8]];
        graph.current_bundle = bundle;
    }

    //========================================================================
    // Return the timestamp of the beginning of the current UTC hour.
    //-------------------------------------------------------------------
    function toStartOfUTCHour(date) {
        var d = (date instanceof Date ? date.getTime() : date);
        d = Math.floor(d/3600000)*3600000;
        return (date instanceof Date ? new Date(d) : d);
    }

    //========================================================================
    // Start a timer to refresh the timeline (without fetch) at the top of the hour.
    //-------------------------------------------------------------------
    function start_refresh_timer() {
        var now = Date.now();
        var next_hour = toStartOfUTCHour(now) + 3601000; // 1 second past the next UTC hour.
        var wait_time = (next_hour - now);
        setTimeout(function(){
            bundle_by_timeslot();
            update_slider_reviews();
            draw_timeline();
            start_refresh_timer();
        }, wait_time);
    }

})(window.timeline);