server/src/models/Notification.js

const mongoose = require('mongoose');

const notificationSchema = new mongoose.Schema({
    recipient: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'User',
        required: true
    },
    type: {
        type: String,
        enum: ['booking', 'message', 'review', 'system'],
        required: true
    },
    content: {
        type: String,
        required: true
    },
    link: {
        type: String
    },
    isRead: {
        type: Boolean,
        default: false
    }
}, { timestamps: true });

// Index for fetching unread notifications for a user
notificationSchema.index({ recipient: 1, isRead: 1 });

const Notification = mongoose.model('Notification', notificationSchema);
module.exports = Notification;