const mongoose = require('mongoose');
const mongoosePaginate = require('mongoose-paginate-v2');
const s3Storage = require('../plugins/s3Storage');

function pdfUri(uri) {
  if (!uri) return null;
  if (uri.startsWith('http://') || uri.startsWith('https://')) return uri;
  const fileName = uri.startsWith('/') ? uri.split('/').pop() : uri;
  return s3Storage.getPublicUrl(`uploads/pdf/${fileName}`);
}

function slideUrl(slide) {
  if (!slide) return null;
  if (slide.startsWith('http://') || slide.startsWith('https://')) return slide;
  const imageName = slide.startsWith('/') ? slide.split('/').pop() : slide;
  const key = imageName.endsWith('.jpeg')
    ? `uploads/books/${imageName}`
    : `uploads/books/${imageName}.jpeg`;
  return s3Storage.getPublicUrl(key);
}

const BookSchema = mongoose.Schema({
    title: String,
    uri: { type: String, get: pdfUri, default: null },
    slides: {
        default: [],
        type: [String],
        get: (slides) => (slides || []).map(slideUrl),
    }
});

BookSchema.plugin(mongoosePaginate);

module.exports = mongoose.model('Book', BookSchema);