github-calendar-parser/lib/index.js

Parses the GitHub contributions calendar SVG code into JSON.

"use strict";

var colorLegend = require("github-calendar-legend");

/**
 * parseGitHubCalendarSvg
 * Parses the SVG input (as string).
 *
 * @name parseGitHubCalendarSvg
 * @function
 * @param {String} input The SVG code of the contributions calendar.
 * @return {Object} An object containing:
 *
 *  - `last_year` (Number): The total contributions in the last year.
 *  - `longest_streak` (Number): The longest streak.
 *  - `longest_streak_range` (Array): An array of two date objects representing the date range.
 *  - `current_streak` (Number): The current streak.
 *  - `current_streak_range` (Array): An array of two date objects representing the date range.
 *  - `days` (Array): An array of day objects:
 *       - `fill` (String): The hex color.
 *       - `date` (Date): The day date.
 *       - `count` (Number): The number of commits.
 *       - `level` (Number): A number between 0 and 4 (inclusive) representing the contribution level (more commits, higher value).
 *  - `weeks` (Array): The day objects grouped by weeks (arrays).
 *  - `last_contributed` (Date): The last contribution date.
 */
module.exports = function parseGitHubCalendarSvg(input) {

    var data = {
        last_year: 0,
        longest_streak: -1,
        longest_streak_range: [],
        current_streak: 0,
        current_streak_range: [],
        longest_break: -1,
        longest_break_range: [],
        current_break: 0,
        current_break_range: [],
        weeks: [],
        days: [],
        last_contributed: null
    },
        lastWeek = [],
        updateLongestStreak = function updateLongestStreak() {
        if (data.current_streak > data.longest_streak) {
            data.longest_streak = data.current_streak;
            data.longest_streak_range[0] = data.current_streak_range[0];
            data.longest_streak_range[1] = data.current_streak_range[1];
        }
    },
        updateLongestBreak = function updateLongestBreak() {
        if (data.current_break > data.longest_break) {
            data.longest_break = data.current_break;
            data.longest_break_range[0] = data.current_break_range[0];
            data.longest_break_range[1] = data.current_break_range[1];
        }
    };

    input.split("\n").slice(2).map(function (c) {
        return c.trim();
    }).forEach(function (c) {
        if (c.startsWith("<g transform")) {
            return lastWeek.length && data.weeks.push(lastWeek) && (lastWeek = []);
        }

        var level = c.match(/data-level="([0-9\-]+)"/i),
            date = c.match(/data-date="([0-9\-]+)"/),
            count = c.match(/(No|[0-9]+)( contribution)/);

        level = level && level[1];
        date = date && date[1];
        if (count) {
            if (count[1] === "No") {
                count[1] = 0;
            }
            count = +count[1];
        } else {
            count = 0;
        }

        if (!level) {
            return;
        }

        var fill = colorLegend[level];

        var obj = {
            fill: fill,
            date: new Date(date),
            count: count,
            level: level
        };

        if (data.current_streak === 0) {
            data.current_streak_range[0] = obj.date;
        }

        if (data.current_break === 0) {
            data.current_break_range[0] = obj.date;
        }

        if (obj.count) {
            ++data.current_streak;
            data.last_year += obj.count;
            data.last_contributed = obj.date;
            data.current_streak_range[1] = obj.date;

            updateLongestBreak();
            data.current_break = 0;
        } else {
            updateLongestStreak();
            data.current_streak = 0;

            ++data.current_break;
            data.current_break_range[1] = obj.date;
        }

        lastWeek.push(obj);
        data.days.push(obj);
    });

    updateLongestStreak();

    return data;
};