const SiteContent = require('../models/SiteContent');
const { asyncController } = require('../utils/asyncController');

const DEFAULT_SITE_CONTENT = {
  welcome: {
    title: 'ITS IT Department Kiosk',
    subtitle:
      "Hi I'm ITS IT Department Kiosk, I can help you explore our department, meet our faculty, and discover our achievements.",
    cta: 'Start Exploring',
    footerHint: 'Touch anywhere to begin',
  },
  mainMenu: {
    title: 'Department of Information Technology',
    subtitle: 'What would you like to explore?',
    footerHint: 'Touch any card to explore that section',
    modules: [
      {
        key: 'aboutus',
        label: 'About Us',
        subtitle: 'Learn about our department',
        bg: '#3b82f6',
        href: '/aboutus',
        iconImage: '',
      },
      {
        key: 'profile',
        label: 'Faculty Profiles',
        subtitle: 'Meet our expert faculty',
        bg: '#8b5cf6',
        href: '/profile',
        iconImage: '',
      },
      {
        key: 'admission',
        label: 'Admissions/Other Info',
        subtitle: 'Join our program',
        bg: '#06b6d4',
        href: '/admission',
        iconImage: '',
      },
      {
        key: 'achievement',
        label: 'Achievements/News',
        subtitle: 'Our success stories',
        bg: '#f97316',
        href: '/achievement',
        iconImage: '',
      },
      {
        key: 'announcement',
        label: 'Announcements',
        subtitle: 'Latest updates and news',
        bg: '#22c55e',
        href: '/announcement',
        iconImage: '',
      },
    ],
  },
};

const sanitizeCopy = (value, fallback) => {
  if (!value || typeof value !== 'object') return fallback;
  return {
    title: String(value.title || fallback.title).trim(),
    subtitle: String(value.subtitle || fallback.subtitle).trim(),
    cta: String(value.cta || fallback.cta).trim(),
    footerHint: String(value.footerHint || fallback.footerHint).trim(),
  };
};

const toKeySlug = (value = '') =>
  String(value)
    .toLowerCase()
    .trim()
    .replace(/[^a-z0-9\s-]/g, '')
    .replace(/\s+/g, '-')
    .replace(/-+/g, '-');

const sanitizeModule = (item = {}, fallback = {}) => ({
  key: String(item.key || fallback.key || '').trim(),
  label: String(item.label || fallback.label || '').trim(),
  subtitle: String(item.subtitle || fallback.subtitle || '').trim(),
  bg: String(item.bg || fallback.bg || '#3b82f6').trim(),
  href: String(item.href || fallback.href || '').trim(),
  iconImage: String(item.iconImage || fallback.iconImage || '').trim(),
});

const sanitizeMainMenu = (value) => {
  const fallback = DEFAULT_SITE_CONTENT.mainMenu;
  const modules = Array.isArray(value?.modules) && value.modules.length
    ? value.modules
    : fallback.modules;

  return {
    title: value?.title || fallback.title,
    subtitle: value?.subtitle || fallback.subtitle,
    footerHint: value?.footerHint || fallback.footerHint,
    modules: modules
      .map((item, index) => {
        const moduleItem = sanitizeModule(item, fallback.modules[index] || {});
        const generatedKey = toKeySlug(moduleItem.key || moduleItem.label || moduleItem.href || `card-${index + 1}`);
        return {
          ...moduleItem,
          key: generatedKey || `card-${index + 1}`,
        };
      })
      .filter((item) => item.label),
  };
};

const normalizeSiteContent = (doc) => ({
  welcome: sanitizeCopy(doc?.welcome?.EN || doc?.welcome, DEFAULT_SITE_CONTENT.welcome),
  mainMenu: sanitizeMainMenu(doc?.mainMenu),
});

const getSiteContent = asyncController(async (req, res) => {
  const doc = await SiteContent.findOne({ slug: 'main' }).lean();
  res.json(normalizeSiteContent(doc));
});

const updateSiteContent = asyncController(async (req, res) => {
  const { welcome, mainMenu } = req.body;
  const payload = {};

  if (welcome && typeof welcome === 'object') {
    const source = welcome.EN && typeof welcome.EN === 'object' ? welcome.EN : welcome;
    payload.welcome = {
      title: String(source?.title || '').trim(),
      subtitle: String(source?.subtitle || '').trim(),
      cta: String(source?.cta || '').trim(),
      footerHint: String(source?.footerHint || '').trim(),
    };
  }

  if (mainMenu && typeof mainMenu === 'object') {
    payload.mainMenu = {
      title: String(mainMenu?.title || '').trim(),
      subtitle: String(mainMenu?.subtitle || '').trim(),
      footerHint: String(mainMenu?.footerHint || '').trim(),
      modules: Array.isArray(mainMenu?.modules)
        ? mainMenu.modules
          .map((item, index) => {
            const moduleItem = sanitizeModule(item);
            const generatedKey = toKeySlug(moduleItem.key || moduleItem.label || moduleItem.href || `card-${index + 1}`);
            return {
              ...moduleItem,
              key: generatedKey || `card-${index + 1}`,
            };
          })
          .filter((item) => item.label)
        : [],
    };
  }

  if (!Object.keys(payload).length) {
    return res.status(400).json({ message: 'No fields provided to update' });
  }

  const doc = await SiteContent.findOneAndUpdate(
    { slug: 'main' },
    { $set: payload },
    { returnDocument: 'after', upsert: true, runValidators: true }
  );

  if (!doc) {
    return res.status(500).json({ message: 'Failed to persist site content' });
  }

  res.json(normalizeSiteContent(doc));
}, { defaultStatus: 400 });

module.exports = { getSiteContent, updateSiteContent };