'use strict';

const mongoose = require('mongoose');

const pendingStudentSchema = new mongoose.Schema({
  user: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'User',
    required: true,
    index: true
  },
  class: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'Class',
    required: true,
    index: true
  },
  course: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'Course',
    required: true
  },
  type: {
    type: String,
    enum: ['enrollment', 'class_request'],
    required: true
  },
  paymentPlan: {
    type: String,
    enum: ['full', 'installments', 'deposit'],
    required: true
  },
  tuitionFee: { type: Number, required: true, min: 0 },
  classDiscount: { type: Number, default: 0, min: 0 },
  paymentDiscount: { type: Number, default: 0, min: 0 },
  totalAmount: { type: Number, required: true, min: 0 },
  amountDueNow: { type: Number, required: true, min: 0 },
  secondInstallmentAmount: { type: Number, default: 0, min: 0 },
  secondInstallmentDueDate: { type: Date },
  status: {
    type: String,
    enum: ['pending_payment', 'pending_review', 'approved', 'rejected', 'cancelled'],
    default: 'pending_review',
    index: true
  },
  payment: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'Payment'
  },
  paymentReference: { type: String, trim: true },
  adminNotes: { type: String, trim: true, maxlength: 2000 },
  reviewedBy: { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
  reviewedAt: { type: Date }
}, {
  timestamps: true
});

pendingStudentSchema.index({ user: 1, class: 1, type: 1, status: 1 });

module.exports = mongoose.model('PendingStudent', pendingStudentSchema);