const { addBaseUrlToImages } = require("../utils/imageHelper");
const Home = require("../models/home");

// -------------------- Helpers --------------------

const getHomeDoc = async () => {
  // Keep newest document as the source of truth
  return await Home.findOne().sort({ updatedAt: -1 });
};

const getHomeData = async () => {
  const doc = await Home.findOne().sort({ updatedAt: -1 }).lean();
  return doc || {};
};

/**
 * Default structure used by the current CMS Home admin UI (`views/admin/home/index.ejs`).
 * This is intentionally permissive; the Home model itself also supports the Next.js
 * structure from `hailearning.edu.vn/app/home.json`.
 */
const getDefaultHomeData = () => ({
  hero: {
    title: "",
    description: "",
    backgroundImage: "",
    button: { label: "Book Your Adventure", href: "/booking" },
    contactBox: {
      welcomeText: "",
      phone: { label: "Call us", number: "", href: "" },
      email: { label: "Email", address: "", href: "" },
      workingHours: { label: "Working Hours", hours: "" },
    },
  },
  about: {
    title: "",
    subtitle: "",
    description: "",
    images: { mainImage1: "", mainImage2: "", avatars: [] },
    features: [],
    quote: "",
    button: { label: "", href: "" },
    stats: { customerCount: 0, customerLabel: "" },
  },
  missionVision: {
    title: "",
    subtitle: "",
    backgroundImage: "",
    cards: [],
  },
  whyChooseUs: {
    title: "",
    subtitle: "",
    description: "",
    button: { label: "", href: "" },
    features: [],
    tags: [],
    cta: { text: "", linkText: "", linkHref: "" },
  },
  activities: { cards: [] },
  faq: {
    title: "",
    subtitle: "",
    description: "",
    image: "",
    contact: { title: "", info: "" },
    questions: [],
  },
  partners: {
    title: "",
    subtitle: "",
    backgroundImage: "",
    logos: [],
    cta: { badge: "", text: "", linkText: "", linkHref: "" },
  },
  programs: {
    title: "",
    subtitle: "",
    button: { label: "", href: "" },
    card: {
      pricePrefix: "from",
      priceSuffix: "USD",
      buttonLabel: "Camp Detail",
      buttonHref: "/camp-profiles",
    },
    items: [],
  },
  newsletter: {
    title: "",
    subtitle: "",
    description: "",
    image: "",
    decorativeImage: "",
    button: { label: "", placeholder: "", href: "" },
  },
  latestPosts: {
    title: "",
    subtitle: "",
    searchPlaceholder: "",
    sidebarTitle: "",
    blogPosts: [],
    sidebarPosts: [],
    featuredCard: { image: "", title: "", description: "" },
  },
});

// -------------------- Admin --------------------

exports.index = async (req, res) => {
  try {
    let data = await getHomeData();

    if (!data || Object.keys(data).length === 0) {
      data = getDefaultHomeData();
    } else {
      // Merge minimal defaults to keep the view safe
      const defaults = getDefaultHomeData();
      data.hero = data.hero || defaults.hero;
      data.about = data.about || defaults.about;
      data.missionVision = data.missionVision || defaults.missionVision;
      data.whyChooseUs = data.whyChooseUs || defaults.whyChooseUs;
      data.activities = data.activities || defaults.activities;
      data.faq = data.faq || defaults.faq;
      data.partners = data.partners || defaults.partners;
      data.programs = data.programs || defaults.programs;
      data.newsletter = data.newsletter || defaults.newsletter;
      data.latestPosts = data.latestPosts || defaults.latestPosts;
    }

    const frontendUrl = process.env.FRONTEND_URL || "http://localhost:3000";

    return res.render("admin/home/index", {
      layout: "layouts/main",
      title: "Home Management",
      data,
      frontendUrl,
      currentPath: req.path,
      user: req.session.user,
    });
  } catch (err) {
    console.error("Home index error:", err);
    req.flash("error_msg", "Error loading home data");
    return req.session.save(() => res.redirect("/admin/dashboard"));
  }
};

exports.update = async (req, res) => {
  try {
    const currentDoc = await getHomeDoc();
    const currentData = currentDoc ? currentDoc.toObject() : {};
    const updatedData = { ...currentData };

    // Quick fields (Hero) from classic form fields
    if (req.body.heroTitle || req.body.heroDescription || req.body.heroBackgroundImage) {
      updatedData.hero = {
        title: req.body.heroTitle || "",
        description: req.body.heroDescription || "",
        backgroundImage: req.body.heroBackgroundImage || "",
        button: {
          label: req.body.heroButtonLabel || "Book Your Adventure",
          href: req.body.heroButtonHref || "/booking",
        },
        contactBox: {
          welcomeText: req.body.heroContactWelcome || "",
          phone: {
            label: "Call us",
            number: req.body.heroContactPhone || "",
            href: req.body.heroContactPhone ? `tel:${req.body.heroContactPhone}` : "",
          },
          email: {
            label: "Email",
            address: req.body.heroContactEmail || "",
            href: req.body.heroContactEmail ? `mailto:${req.body.heroContactEmail}` : "",
          },
          workingHours: {
            label: "Working Hours",
            hours: req.body.heroContactHours || "",
          },
        },
      };
    }

    // Handle sections sent as JSON payloads
    const sections = [
      "hero",
      "about",
      "missionVision",
      "whyChooseUs",
      "activities",
      "faq",
      "partners",
      "programs",
      "newsletter",
      "latestPosts",
    ];

    let hasChanges = false;

    for (const section of sections) {
      if (!req.body[section]) continue;

      try {
        const newSectionData = JSON.parse(req.body[section]);
        const currentSectionData = currentData?.[section];

        if (JSON.stringify(newSectionData) !== JSON.stringify(currentSectionData)) {
          updatedData[section] = newSectionData;
          hasChanges = true;
        }
      } catch (e) {
        console.error(`Error processing section "${section}":`, e);
        req.flash("error_msg", `Invalid JSON for section "${section}": ${e.message}`);
        return req.session.save(() => res.redirect("/admin/home"));
      }
    }

    if (!hasChanges) {
      req.flash("info_msg", "No changes were made");
      return req.session.save(() => res.redirect("/admin/home"));
    }

    if (currentDoc?._id) {
      await Home.findByIdAndUpdate(currentDoc._id, updatedData, { new: true });
    } else {
      await Home.create(updatedData);
    }

    req.flash("success_msg", "Home data updated successfully");
    return req.session.save(() => res.redirect("/admin/home"));
  } catch (err) {
    console.error("Home update error:", err);
    req.flash("error_msg", `Update error: ${err.message || "Unknown"}`);
    return req.session.save(() => res.redirect("/admin/home"));
  }
};

// -------------------- Public API --------------------

exports.api = async (req, res) => {
  try {
    const homeData = await getHomeData();
    const baseUrl = process.env.BACKEND_URL || `${req.protocol}://${req.get("host")}`;
    const processedData = addBaseUrlToImages(homeData, baseUrl);
    return res.json(processedData);
  } catch (err) {
    console.error("Home API error:", err);
    return res.status(500).json({ error: "Error loading home data" });
  }
};