'use strict';

const net = require('node:net');

function sourceUrl(value, prefix) {
  const url = new URL(value);
  if (url.protocol !== 'https:' || url.hostname !== 'weebcentral.com' || url.username || url.password || !url.pathname.startsWith(prefix)) {
    throw new Error('Source plugin returned an unexpected WeebCentral URL');
  }
  return url.href;
}

function imageUrl(value) {
  const url = new URL(value);
  const hostname = url.hostname.toLowerCase();
  if (url.protocol !== 'https:' || url.username || url.password || net.isIP(hostname)
    || hostname === 'localhost' || hostname.endsWith('.localhost') || hostname.endsWith('.local')
    || !hostname.includes('.')) {
    throw new Error('Source plugin returned an unsafe image URL');
  }
  return url.href;
}

function validate(plugin, operation, output) {
  if (plugin !== 'weebcentral' || !output || typeof output !== 'object' || Array.isArray(output)) {
    throw new Error('Invalid source plugin output');
  }
  if (operation === 'series') {
    if (typeof output.title !== 'string' || typeof output.listUrl !== 'string' && output.listUrl !== null) throw new Error('Invalid series parse');
    if (output.listUrl !== null) sourceUrl(output.listUrl, '/series/');
  } else if (operation === 'catalog') {
    if (!Array.isArray(output.chapters) || !Number.isInteger(output.chapterLinks) || output.chapterLinks < 0) throw new Error('Invalid catalog parse');
    for (const chapter of output.chapters) {
      if (!chapter || typeof chapter.id !== 'string' || typeof chapter.number !== 'string') throw new Error('Invalid chapter reference');
      sourceUrl(chapter.url, '/chapters/');
    }
  } else if (operation === 'chapter') {
    sourceUrl(output.manifestUrl, '/chapters/');
    if (!new URL(output.manifestUrl).pathname.endsWith('/images')) throw new Error('Invalid chapter image manifest');
  } else if (operation === 'pages') {
    if (!Array.isArray(output.pages)) throw new Error('Invalid page parse');
    for (const page of output.pages) imageUrl(page);
  } else throw new Error('Unknown source plugin operation');
  return output;
}

module.exports = { validate };