// ==UserScript==
// @name         UESTC 研究生课表ics导出
// @namespace    http://tampermonkey.net/
// @version      1.1
// @description  一键导出课表的ics文件，方便各系统加入原生日历应用
// @author       ygowill
// @match        https://yjsjy.uestc.edu.cn/pyxx/pygl/xskbcx/index/*
// @require      https://cdn.jsdelivr.net/gh/nwcell/ics.js@dfec67f37a3c267b3f97dd229c9b6a3521222794/demo/ics.deps.min.js
// @grant        none
// @license      MIT
// @downloadURL none
// ==/UserScript==

(function () {
    'use strict';

    Date.prototype.format = function (fmt) {
        var o = {
            "M+": this.getMonth() + 1, //月份
            "d+": this.getDate(), //日
            "h+": this.getHours(), //小时
            "m+": this.getMinutes(), //分
            "s+": this.getSeconds(), //秒
            "q+": Math.floor((this.getMonth() + 3) / 3), //季度
            "S": this.getMilliseconds() //毫秒
        };
        if (/(y+)/.test(fmt)) {
            fmt = fmt.replace(RegExp.$1, (this.getFullYear() + "").substr(4 - RegExp.$1.length));
        }
        for (var k in o) {
            if (new RegExp("(" + k + ")").test(fmt)) {
                fmt = fmt.replace(RegExp.$1, (RegExp.$1.length == 1) ? (o[k]) : (("00" + o[k]).substr(("" + o[k]).length)));
            }
        }
        return fmt;
    }

    const start_monday_date = new Date("2021-03-01"); // 实在是不知道从哪里找每学期第一个周一的日期，只能硬编码了
    let week_date_table = []; // 生成本学期所有日期，默认到20周结束
    for (let i = 0; i < 20; i++) {
        let week_arr = []
        for (let j = 0; j < 7; j++) {
            let tmp_date = new Date(start_monday_date);
            tmp_date.setDate(tmp_date.getDate() + 7 * i + j);
            week_arr.push(tmp_date);
        }
        week_date_table.push(week_arr);
    }

    let timeTable = [ // 硬编码时间表
        ["08:30", "09:15"], // startTime, endTime
        ["09:20", "10:05"],
        ["10:20", "11:05"],
        ["11:10", "11:55"],
        ["14:30", "15:15"],
        ["15:20", "16:05"],
        ["16:20", "17:05"],
        ["17:10", "17:55"],
        ["19:30", "20:15"],
        ["20:20", "21:05"],
        ["21:10", "21:55"],
        ["22:00", "22:45"]
    ];

    function generate_button() { // 按钮生成
        let tool_bar = document.getElementsByClassName("widget-toolbar")[0];
        let return_button = document.querySelector("#main-container > div > div > div.page-content > div > div.widget-header.widget-header-large > div > button:nth-child(2)");
        let download_ics = document.createElement("button");
        download_ics.type = "button";
        download_ics.style = "margin-top: 5px; margin-right: 5px;";
        download_ics.className = "btn btn-xs btn-return ";
        download_ics.innerHTML = "<i class=\"icon-hdd  align-top bigger-150\"></i>导出ics文件";
        download_ics.addEventListener("click", parse_table, false);
        tool_bar.insertBefore(download_ics, return_button);
    }

    function parse_table() {
        let cal = ics();
        let table = document.querySelector("#tbl > tbody");
        let table_line_list = table.getElementsByTagName("tr");
        let week_map = new Map();
        for (let no = 1; no < 7; no++) { // no==0 为表头
            for (let day = 0; day < 7; day++) { // day==0 为节标号
                if (typeof (table_line_list[no]) == "undefined") {
                    continue;
                }
                let course_info = table_line_list[no].getElementsByTagName("td")[day + 1].innerText;
                if (course_info.trim() === "") {
                    continue;
                }
                let course_map = new Map();
                let course_list = course_info.split("，");
                for (let course of course_list) { // info example: "0808126007/大数据分析与挖掘(全英文)/40/2/邵俊明/1-10周/(1~2)/品学楼B107"
                    let c_list = course.split("/");
                    let course_id = c_list[0].trim();
                    let week_str = c_list[5];
                    week_str = week_str.substring(0, week_str.length - 1);
                    let time_str = c_list[6];
                    time_str = time_str.substring(1, time_str.length - 1);
                    let start_week = parseInt(week_str.split("-")[0]);
                    let end_week = parseInt(week_str.split("-")[1]);
                    if (!course_map.has(course_id)) {
                        course_map.set(course_id, new Map());
                        course_map.get(course_id).set("course_id", course_id);
                        course_map.get(course_id).set("name", c_list[1]);
                        course_map.get(course_id).set("teacher", c_list[4]);
                        course_map.get(course_id).set("start_time", timeTable[parseInt(time_str.split("~")[0]) - 1][0]);
                        course_map.get(course_id).set("end_time", timeTable[parseInt(time_str.split("~")[1]) - 1][1]);
                        course_map.get(course_id).set("location", c_list[7]);
                    }

                    if (week_map.has(course_id)) {
                        week_map.get(course_id).set("min", Math.min(start_week, week_map.get(course_id).get("min")));
                        week_map.get(course_id).set("max", Math.max(end_week, week_map.get(course_id).get("max")));
                    } else {
                        week_map.set(course_id, new Map());
                        week_map.get(course_id).set("min", start_week);
                        week_map.get(course_id).set("max", end_week);
                    }
                }

                for (let course of course_map.values()) {
                    const start_week = parseInt(week_map.get(course.get("course_id")).get("min"));
                    const end_week = parseInt(week_map.get(course.get("course_id")).get("max"));

                    for (let i=start_week;i<=end_week;i++) {
                        let description = "任课教师：" + course.get("teacher") + "  周：" + start_week + "-" + end_week;
                        // 起止时间
                        let start_time = new Date(start_monday_date);
                        start_time.setDate(start_time.getDate() + (i - 1) * 7 + day);
                        start_time.setHours(course.get("start_time").split(":")[0]);
                        start_time.setMinutes(course.get("start_time").split(":")[1]);

                        let end_time = new Date(start_monday_date);
                        end_time.setDate(end_time.getDate() + (i - 1) * 7 + day);
                        end_time.setHours(course.get("end_time").split(":")[0]);
                        end_time.setMinutes(course.get("end_time").split(":")[1]);

                        cal.addEvent(course.get("name"), description, course.get("location"), start_time.toUTCString(), end_time.toUTCString());
                    }
                }
            }
        }
        cal.download();
    }

    generate_button();
})();