'use strict';

const { generateUniqueCode } = require('./uniqueCode');

/**
 * Mongoose plugin: auto-assigns an 8-digit uniqueCode before validation if missing.
 */
const uniqueCodePlugin = (schema, options = {}) => {
  const field = options.field || 'uniqueCode';

  schema.add({
    [field]: {
      type: String,
      unique: true,
      sparse: true,
      trim: true,
      index: true
    }
  });

  schema.pre('validate', async function assignUniqueCode(next) {
    if (this[field]) return next();
    try {
      this[field] = await generateUniqueCode(this.constructor, field);
      return next();
    } catch (err) {
      return next(err);
    }
  });
};

module.exports = uniqueCodePlugin;