const { getServiceData } = require("../services/service.service");
const Service = require("../models/service");
const syncServiceMenu = require("../services/syncServiceMenu");
const { addBaseUrlToImages, getFullImageUrl } = require("../utils/imageHelper");
const writeAuditLog = require("../audit/writeAuditLog");
const diffObject = require("../audit/diffObject");
const AUDIT_ACTIONS = require("../constants/auditAction");

const slugify = require("slugify");

// Admin page - Service list
exports.index = async (req, res) => {
  try {
    const data = await getServiceData();
    console.log(data.services.items.image);
    res.render("admin/service/index", {
      title: "Service Management",
      data,
      layout: "layouts/main",
      getFullImageUrl, // Truyền helper function vào view
    });
  } catch (err) {
    console.error(err);
    req.flash("error_msg", "Error loading service data");
    res.redirect("/admin/dashboard");
  }
};

// Admin page - Service edit
exports.edit = async (req, res) => {
  try {
    const { slug } = req.params;
    const data = await getServiceData();

    const service = data.services?.items?.find((item) => item.slug === slug);
    if (!service) {
      req.flash("error_msg", "Service not found");
      return res.redirect("/admin/service");
    }

    res.render("admin/service/edit", {
      title: `Edit Service - ${service.name}`,
      service,
      layout: "layouts/main",
      getFullImageUrl,
    });
  } catch (err) {
    console.error(err);
    req.flash("error_msg", "Error loading service for editing");
    res.redirect("/admin/service");
  }
};

// Update single service
exports.updateService = async (req, res) => {
  try {
    const { slug } = req.params;
    const currentData = await getServiceData();

    const serviceIndex = currentData.services?.items?.findIndex(
      (item) => item.slug === slug,
    );
    if (serviceIndex === -1) {
      req.flash("error_msg", "Service not found");
      return res.redirect("/admin/service");
    }

    const oldItem = JSON.parse(
      JSON.stringify(currentData.services.items[serviceIndex]),
    );

    // Update service data
    const updatedData = { ...currentData.toObject?.() };
    updatedData.services.items[serviceIndex] = {
      ...updatedData.services.items[serviceIndex],
      name: req.body.name,
      slug: req.body.slug,
      description: req.body.description,
      image: req.body.image,
      layout: req.body.layout,
    };

    if (currentData._id) {
      await Service.findByIdAndUpdate(currentData._id, updatedData);
    } else {
      await Service.create(updatedData);
    }
    const newItem = updatedData.services.items[serviceIndex];

    const changes = diffObject(oldItem, newItem);
    console.log("USER:", req.session?.user || req.user || "No user found");

    await writeAuditLog({
      model: "Service",
      documentId: currentData._id,
      action: AUDIT_ACTIONS.UPDATE_SERVICE,
      before: oldItem,
      after: newItem,
      changes,
      req,
    });
    // Sync header menu children to reflect updated service name/slug
    await syncServiceMenu(updatedData.services?.items || []);
    req.flash("success_msg", "Service updated successfully");
    res.redirect("/admin/service");
  } catch (err) {
    console.error(err);
    req.flash("error_msg", err.message);
    res.redirect("/admin/service");
  }
};

// Admin page - Service details
exports.details = async (req, res) => {
  try {
    const { slug } = req.params;
    const data = await getServiceData();

    const service = data.services?.items?.find((item) => item.slug === slug);
    if (!service) {
      req.flash("error_msg", "Service not found");
      return res.redirect("/admin/service");
    }

    res.render("admin/service/details", {
      title: `Service Details - ${service.name}`,
      service,
      layout: "layouts/main",
      getFullImageUrl, // Truyền helper function vào view
    });
  } catch (err) {
    console.error(err);
    req.flash("error_msg", "Error loading service details");
    res.redirect("/admin/service");
  }
};

// Update service list
exports.update = async (req, res) => {
  try {
    const currentData = await getServiceData();
    const sections = [
      "pageTitle",
      "services",
      "destinations",
      "visas",
      "reviews",
    ];

    let updatedData = { ...currentData.toObject?.() };
    let hasChanges = false;

    sections.forEach((section) => {
      if (!req.body[section]) return;

      const newData = JSON.parse(req.body[section]);
      if (JSON.stringify(newData) !== JSON.stringify(currentData[section])) {
        updatedData[section] = newData;
        hasChanges = true;
      }
    });

    if (!hasChanges) {
      req.flash("info_msg", "No changes were made");
      return res.redirect("/admin/service");
    }

    if (currentData._id) {
      await Service.findByIdAndUpdate(currentData._id, updatedData);
    } else {
      await Service.create(updatedData);
    }

    // Sync header menu children to reflect current service list
    await syncServiceMenu(updatedData.services?.items || []);

    req.flash("success_msg", "Service updated successfully");
    res.redirect("/admin/service");
  } catch (err) {
    console.error(err);
    req.flash("error_msg", err.message);
    res.redirect("/admin/service");
  }
};

// Update service details
exports.updateDetails = async (req, res) => {
  try {
    const { slug } = req.params;
    const currentData = await getServiceData();

    const serviceIndex = currentData.services?.items?.findIndex(
      (item) => item.slug === slug,
    );
    if (serviceIndex === -1) {
      req.flash("error_msg", "Service not found");
      return res.redirect("/admin/service");
    }
    const beforeDetails = JSON.parse(
      JSON.stringify(currentData.services.items[serviceIndex].details || {}),
    );
    // Parse features and FAQ from JSON strings
    const features = req.body.features ? JSON.parse(req.body.features) : [];
    const faq = req.body.faq ? JSON.parse(req.body.faq) : [];

    // Update service details
    const updatedData = { ...currentData.toObject?.() };
    const updatedDetails = {
      title: req.body.title,
      description: req.body.description,
      mainImage: req.body.mainImage,
      overviewTitle: req.body.overviewTitle,
      overviewDescription: req.body.overviewDescription,
      additionalDescription: req.body.additionalDescription,
      keyFeaturesTitle: req.body.keyFeaturesTitle,
      keyFeaturesImage: req.body.keyFeaturesImage,
      features,
      faqTitle: req.body.faqTitle,
      faqImage: req.body.faqImage,
      faq,
    };

    updatedData.services.items[serviceIndex].details = updatedDetails;
    if (currentData._id) {
      await Service.findByIdAndUpdate(currentData._id, updatedData);
    } else {
      await Service.create(updatedData);
    }
    const changes = diffObject(beforeDetails, updatedDetails);
    if (changes.length > 0) {
      await writeAuditLog({
        model: "Service",
        documentId: currentData._id,
        action: AUDIT_ACTIONS.UPDATE_SERVICE_DETAILS,
        before: beforeDetails,
        after: updatedDetails,
        changes,
        req,
      });
    }

    req.flash("success_msg", "Service details updated successfully");
    res.redirect(`/admin/service/${slug}/details`);
  } catch (err) {
    console.error(err);
    req.flash("error_msg", err.message);
    res.redirect("/admin/service");
  }
};

// API endpoint
exports.api = async (req, res) => {
  try {
    const serviceData = await getServiceData();
    const baseUrl =
      process.env.BACKEND_URL || `${req.protocol}://${req.get("host")}`;

    const processedData = addBaseUrlToImages(serviceData, baseUrl);
    res.json(processedData);
  } catch (err) {
    res.status(500).json({ error: "Error loading service data" });
  }
};

/**
 * Get service details by slug - API endpoint
 */
exports.getServiceBySlug = async (req, res) => {
  try {
    const { slug } = req.params;

    const serviceDoc = await Service.findOne().lean();

    if (!serviceDoc) {
      return res.status(404).json({
        success: false,
        message: "Service data not found",
      });
    }

    // Find service by slug
    const service = serviceDoc.services?.items?.find(
      (item) => item.slug === slug,
    );

    if (!service) {
      return res.status(404).json({
        success: false,
        message: `Service with slug '${slug}' not found`,
      });
    }

    const baseUrl =
      process.env.BACKEND_URL || `${req.protocol}://${req.get("host")}`;

    // Return service details in the expected format
    const responseData = {
      pageTitle: serviceDoc.pageTitle,
      breadcrumb: {
        ...serviceDoc.breadcrumb,
        title: "Service Details",
        items: [
          { label: "Home", href: "/" },
          { label: "Services", href: "/services" },
          { label: service.name, href: `/services/${slug}` },
        ],
      },
      serviceDetails: {
        content: service.details,
        keyFeatures: {
          title: service.details.keyFeaturesTitle || "Key Features",
          sideImage: service.details.keyFeaturesImage || "img/default.jpg",
          items: service.details.features || [],
        },
        faq: {
          title: service.details.faqTitle || "Frequently Asked Questions",
          sideImage: service.details.faqImage || "img/default.jpg",
          items: service.details.faq || [],
        },
      },
    };

    const processedData = addBaseUrlToImages(responseData, baseUrl);
    res.json(processedData);
  } catch (error) {
    console.error("Error fetching service by slug:", error);
    res.status(500).json({
      success: false,
      message: "Internal server error",
      error: error.message,
    });
  }
};

/**
 * Generate slug from text - API endpoint
 */
exports.generateSlug = async (req, res) => {
  try {
    const { text } = req.body;

    if (!text || typeof text !== "string") {
      return res.status(400).json({
        success: false,
        message: "Text is required",
      });
    }

    // Generate slug using slugify library with Vietnamese support
    const slug = slugify(text, {
      lower: true,
      strict: true,
      locale: "vi",
    });

    res.json({
      success: true,
      slug: slug,
    });
  } catch (error) {
    console.error("Error generating slug:", error);
    res.status(500).json({
      success: false,
      message: "Internal server error",
      error: error.message,
    });
  }
};

/**
 * Get all service slugs - API endpoint
 */
exports.getServiceSlugs = async (req, res) => {
  try {
    const serviceDoc = await Service.findOne().lean();

    if (!serviceDoc?.services?.items) {
      return res.json({
        success: true,
        slugs: [],
      });
    }

    const slugs = serviceDoc.services.items.map((item) => ({
      slug: item.slug,
      name: item.name,
      id: item.id,
    }));

    res.json({
      success: true,
      slugs,
    });
  } catch (error) {
    console.error("Error fetching service slugs:", error);
    res.status(500).json({
      success: false,
      message: "Internal server error",
      error: error.message,
    });
  }
};