// /components/courses/courseModel.js

const mongoose = require('mongoose');

const discountSchema = new mongoose.Schema({
  percent: { type: Number, required: true, min: 0, max: 100 },
  validFrom: { type: Date, required: true },
  validTo: { type: Date, required: true },
  isActive: { type: Boolean, default: true }
});

const offerSchema = new mongoose.Schema({
  title: { type: String, required: true, trim: true },
  description: { type: String, trim: true },
  type: {
    type: String,
    enum: ['fullAdvancePayment', 'earlyBird', 'custom'],
    required: true
  },
  percent: { type: Number, min: 0, max: 100 },
  fixedAmount: { type: Number, min: 0 },
  validFrom: { type: Date },
  validTo: { type: Date },
  isActive: { type: Boolean, default: true }
});

const courseSchema = new mongoose.Schema({
  title: {
    type: String,
    required: true,
    trim: true,
    index: true
  },
  description: {
    type: String,
    trim: true
  },
  type: {
    type: String,
    enum: ['General', 'Private'],
    required: true
  },
  price: {
    type: Number,
    required: true,
    min: 0
  },
  rating: {
    type: Number,
    default: 0,
    min: 0,
    max: 5
  },
  isOfficial: {
    type: Boolean,
    default: false
  },
  /** When true, course appears on the public website */
  showOnFrontend: {
    type: Boolean,
    default: true,
    index: true
  },
  /** Number of sessions in the course */
  sectionCount: {
    type: Number,
    default: 1,
    min: 1
  },
  /** Hours per session */
  hoursPerSection: {
    type: Number,
    default: 1.5,
    min: 0
  },
  /** Bullet-point highlights shown on the frontend */
  highlights: [{
    type: String,
    trim: true
  }],
  professor: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'Professor'
  },
  discounts: [discountSchema],
  offers: [offerSchema],
  capacity: {
    type: Number,
    default: 30
  }
}, {
  timestamps: true
});

module.exports = mongoose.model('Course', courseSchema);