Get all content downloads of any nptel course. \n Adds a button on the nav bar to run the script.
// ==UserScript==
// @name NPTEL-Save-Sourse-Content
// @match https://onlinecourses.nptel.ac.in/*
// @grant GM_setValue
// @license MIT
// @description Get all content downloads of any nptel course. \n Adds a button on the nav bar to run the script.
// @version 0.4.4
// @namespace https://greasyfork.org/users/941655
// ==/UserScript==
const courseContentWeeks = [];
const DEBUG = false;
/** @typedef {'assignment'|'material'|'book'|'transcript'|'lecture'|'video'|'notes'} ITEM_TYPE */
/**
* @typedef {Object} Course
* @property {string} title
* @property {ITEM_TYPE} type
* @property {string} href
* @property {string} data
* @property {string} meta
*/
/**@type {ITEM_TYPE}*/
const DEBUG_TYPE = "notes";
/**@type {Map<ITEM_TYPE, Boolean>}*/
const allowedTypes = new Map([
["assignment", true],
["material", true],
["notes", true],
["book", true],
["transcript", true],
["lecture", true],
["video", false],
]);
/**
* @param {Course} course
*/
const getContent = async (course) => {
let ret = null;
let meta = null;
switch (course.type) {
case "assignment":
case "material":
{
const body = await (await fetch(course.href)).text();
const dom = new DOMParser().parseFromString(body, "text/html");
ret = dom.querySelector('.gcb-lesson-content a[target]')
?.getAttribute("href");
if (!ret) {
ret = dom.querySelector(
'iframe[src^="https://drive"], iframe[src^="https://docs.google.com"]',
)?.getAttribute("src");
!ret && DEBUG && console.log("[Error] No link found");
}
}
break;
case "transcript":
case "lecture":
case "book":
case "notes":
{
const body = await (await fetch(course.href)).text();
const dom = new DOMParser().parseFromString(body, "text/html");
const a = dom.querySelector(".gcb-lesson-content a[target]");
if (a) {
course.title = a.parentElement.textContent || course.type;
ret = a.href;
} else DEBUG && console.log("[Error] No link found");
}
break;
case "video":
{
const body = await (await fetch(course.href)).text();
const videoId = body.match(/loadIFramePlayer\(['"](.+)['"],/)?.[1];
const dom = new DOMParser().parseFromString(body, "text/html");
meta = dom.querySelector("div.gcb-lesson-content > span")?.innerText;
!videoId && DEBUG && console.log("[Error] No link found");
ret = `https://www.youtube.com/watch?v=${videoId}`;
}
break;
default:
DEBUG && console.log("UNIMPLEMENTED type", course);
break;
}
DEBUG && console.log(course.title);
return { ...course, data: ret, meta };
};
/**
* @param {ITEM_TYPE} type
* @param {Array} week
* @param {Object} content
*/
const appendContent = (type, week, content) => {
if (DEBUG) {
if (type === DEBUG_TYPE) {
week.push(content);
}
} else if (allowedTypes.get(type)) {
week.push(content);
}
};
const fetchContent = async () => {
const nodes = document.querySelectorAll(
"div[id^=unit_navbar] > ul[id^=subunit_navbar]",
);
nodes.forEach((el) => {
const week = [];
const tags = el.querySelectorAll("li > div > a");
tags.forEach((tag) => {
const thing = tag.textContent.toLowerCase();
/**@type {ITEM_TYPE}*/
let type;
if (thing.includes("solution")) {
type = "assignment";
appendContent(type, week, {
href: tag.getAttribute("href"),
title: tag.textContent,
type,
});
} else if (thing.includes("lecture notes")) {
type = "notes";
appendContent(type, week, {
href: tag.getAttribute("href"),
title: tag.textContent,
type,
});
} else if (thing.includes("course material")) {
type = "material";
appendContent(type, week, {
href: tag.getAttribute("href"),
title: tag.textContent,
type,
});
} else if (thing.includes("book")) {
type = "book";
appendContent(type, week, {
href: tag.getAttribute("href"),
title: tag.textContent,
type,
});
} else if (thing.includes("transcript")) {
type = "transcript";
appendContent(type, week, {
href: tag.getAttribute("href"),
title: tag.textContent,
type,
});
} else if (thing.includes("lecture material")) {
type = "lecture";
appendContent(type, week, {
href: tag.getAttribute("href"),
title: tag.textContent,
type,
});
} else if (
thing.match(/lec(ture)? ?\d+ ?:/) !== null ||
thing.match(/part \d/) !== null
) {
type = "video";
appendContent(type, week, {
href: tag.getAttribute("href"),
title: tag.textContent,
type,
});
} else {
// DEBUG && console.log("UNKNOWN thing", thing);
}
});
week.length && courseContentWeeks.push(week);
});
await courseContents();
};
const courseContents = async () => {
const promises = [];
const total = courseContentWeeks.flat().length;
for (let weekIdx = 0; weekIdx < courseContentWeeks.length; ++weekIdx) {
for (let i = 0; i < courseContentWeeks[weekIdx].length; ++i) {
promises.push(updateContent(weekIdx, i, total));
}
}
await Promise.all(promises);
};
const updateContent = async (weekIdx, i, total) => {
const el = courseContentWeeks[weekIdx][i];
courseContentWeeks[weekIdx][i] = await getContent(el);
incrementProgress(total);
};
/**
* Builds a table from the given objects.
* @param {Array<String>} labels
* @param {Array} objects
* @param {HTMLElement} container
*/
function buildTable(labels, objects, container) {
container.querySelector("table")?.remove();
const table = document.createElement("table");
table.style.textAlign = "center";
table.style.width = "100%";
const thead = document.createElement("thead");
const tbody = document.createElement("tbody");
const theadTr = document.createElement("tr");
for (let i = 0; i < labels.length; ++i) {
const theadTh = document.createElement("th");
theadTh.innerHTML = labels[i].toUpperCase();
theadTr.appendChild(theadTh);
}
thead.appendChild(theadTr);
table.appendChild(thead);
for (let j = 0; j < objects.length; ++j) {
const tbodyTr = document.createElement("tr");
for (let k = 0; k < labels.length; ++k) {
const tbodyTd = document.createElement("td");
tbodyTd.style.padding = "10px";
if (objects[j][labels[k]]?.startsWith("http")) {
const a = document.createElement("a");
a.href = objects[j][labels[k]];
a.target = "_blank";
a.innerHTML = "Open Link";
if (objects[j]["meta"]) {
const p = document.createElement("p");
p.innerHTML = objects[j]["meta"];
tbodyTd.appendChild(p);
}
tbodyTd.appendChild(a);
} else {
tbodyTd.innerHTML = objects[j][labels[k]];
}
tbodyTr.appendChild(tbodyTd);
}
tbody.appendChild(tbodyTr);
}
table.appendChild(tbody);
container.prepend(table);
}
const nav = document.querySelector(".gcb-aux");
const button = document.createElement("button");
const progressDiv = document.createElement("div");
progressDiv.appendChild(document.createTextNode("Please wait..."));
const progress = document.createElement("span");
progressDiv.appendChild(progress);
const itemListDiv = document.createElement("div");
Array.from(allowedTypes.keys()).forEach((item) => {
const checkbox = document.createElement("input");
checkbox.type = "checkbox";
checkbox.id = item;
checkbox.checked = allowedTypes.get(item);
checkbox.addEventListener("change", () => {
allowedTypes.set(item, checkbox.checked);
});
const label = document.createElement("label");
label.htmlFor = item;
label.textContent = item;
itemListDiv.appendChild(checkbox);
itemListDiv.appendChild(label);
itemListDiv.appendChild(document.createElement("br"));
});
const setProgress = (val) => {
progress.innerText = `${val.toPrecision(2)}%`;
};
const incrementProgress = (total) => {
const val = parseFloat(progress.innerText.replace("%", ""));
setProgress(val + 100 / total);
};
button.innerHTML = "Run Script";
progressDiv.style.display = "none";
button.onclick = async () => {
console.log("scriptMain");
setProgress(0);
courseContentWeeks.length = 0;
progressDiv.style.display = "block";
await fetchContent();
progressDiv.style.display = "none";
console.table(courseContentWeeks.flat());
buildTable(
["title", "type", "data"],
courseContentWeeks.flat(),
document.getElementById("gcb-main-body"),
);
console.log(courseContentWeeks);
};
nav.appendChild(button);
nav.appendChild(progressDiv);
nav.appendChild(itemListDiv);
(async () => {
await new Promise((resolve) => setTimeout(resolve, 1000));
console.clear();
})();