updateClassDate.js

//! Run 'npm run refresh' to execute this script and refresh the class dates
// Script to randomize instructor class dates for demo purposes

const { MongoClient } = require("mongodb");
require("dotenv").config();
const uri = `mongodb+srv://${process.env.DB_USER}:${process.env.DB_PASS}@cluster0.y70m6ei.mongodb.net/?retryWrites=true&w=majority`;
const client = new MongoClient(uri);

function randomStartDate() {
    // Range: 40 days in the past to 30 days in the future
    const pastRange = 40;
    const futureRange = 30;
    const now = Date.now();
    const start = now - pastRange * 24 * 60 * 60 * 1000;
    const end = now + futureRange * 24 * 60 * 60 * 1000;
    return new Date(start + Math.random() * (end - start));
}

function randomEndDate(startDate) {
    const min = 3,
        max = 30;
    const offset = Math.floor(Math.random() * (max - min + 1)) + min;
    const result = new Date(startDate);
    result.setDate(result.getDate() + offset);
    return result;
}

async function refreshCourses() {
    await client.connect();
    const db = client.db("PMBIA");
    const users = db.collection("users");
    const bookings = db.collection("bookings");

    const instructors = await users
        .find({ role: "Instructor" }, { projection: { classes: 1, name: 1 } })
        .toArray();

    if (!instructors.length) {
        console.error("No instructors found.");
        await client.close();
        return;
    }

    for (const instructor of instructors) {
        const originalClasses = instructor?.classes || [];
        const updatedClasses = [];

        for (let i = 0; i < originalClasses.length; i++) {
            const cls = originalClasses[i];
            const startDate = randomStartDate();
            const endDate = randomEndDate(startDate);

            updatedClasses.push({ ...cls, startDate, endDate });

            await bookings.updateMany(
                {
                    instructorId: instructor._id,
                    classIndex: i,
                },
                {
                    $set: {
                        startDate,
                        endDate,
                    },
                }
            );
        }

        await users.updateOne(
            { _id: instructor._id },
            {
                $set: {
                    classes: updatedClasses,
                    "meta.lastUpdated": new Date(),
                },
            }
        );

        console.log(`✅ Updated classes for instructor: ${instructor.name}`);
    }

    console.log("🎉 All instructor classes updated!");
    await client.close();
}

module.exports = { refreshCourses };

// If run directly, execute refreshCourses
if (require.main === module) {
    refreshCourses().catch((err) => {
        console.error("Error updating instructor classes:", err);
        client.close();
    });
}