Function groupHighlights

src/scripts/highlighting/textHighlighter.js:151–182

* Groups given highlights by timestamp. * @param {Array} highlights * @returns {Array} Grouped highlights.

(highlights)

     * @returns {Array} Grouped highlights.
     */
    function groupHighlights(highlights) {
        var order = [],
            chunks = {},
            grouped = [];

        highlights.forEach(function (hl) {
            var timestamp = hl.getAttribute(TIMESTAMP_ATTR);

            if (typeof chunks[timestamp] === 'undefined') {
                chunks[timestamp] = [];
                order.push(timestamp);
            }

            chunks[timestamp].push(hl);
        });

        order.forEach(function (timestamp) {
            var group = chunks[timestamp];

            grouped.push({
                chunks: group,
                timestamp: timestamp,
                toString: function () {
                    return group.map(function (h) {
                        return h.textContent;
                    }).join('');
                }
            });
        });

        return grouped;
    }

    /**
     * Utility functions to make DOM manipulation easier.