eCommerce-backend/src/controllers/admin/categoryController.js

const { prisma } = require('../../config/database');

exports.getAllCategories = async (req, res, next) => {
  try {
    const categories = await prisma.category.findMany({
      orderBy: { name: 'asc' },
    });
    // res.json({ success: true, data: categories });
    res.status(200).json({
      // statusCode: 200,
      status: true,
      message: 'Categories fetched successfully',
      data: categories,
    });
  } catch (error) {
    next(error);
  }
};

exports.createCategory = async (req, res, next) => {
  try {
    const { name, description, image, parentId, metaTitle, metaDescription } =
      req.body;

    // Generate slug from name
    let slug = name
      .toLowerCase()
      .replace(/[^a-z0-9]+/g, '-')
      .replace(/(^-|-$)/g, '');

    // Check if slug already exists with the same parent
    const existing = await prisma.category.findFirst({
      where: {
        slug,
        parentId: parentId || null, // Handle both subcategories and root categories
      },
    });

    if (existing) {
      // If exists under same parent, append timestamp to make it unique
      slug = `${slug}-${Date.now()}`;
    }

    const category = await prisma.category.create({
      data: {
        name,
        slug,
        description,
        image,
        parentId,
        metaTitle,
        metaDescription,
      },
    });

    res.status(201).json({
      statusCode: 201,
      status: true,
      message: 'Category created successfully',
      data: category,
    });
  } catch (error) {
    // Handle Prisma duplicate error explicitly
    if (error.code === 'P2002') {
      return res.status(400).json({
        statusCode: 400,
        status: false,
        message: 'Duplicate field value entered',
      });
    }
    next(error);
  }
};

exports.updateCategory = async (req, res, next) => {
  try {
    const { id } = req.params;
    const { name, description, image, parentId, metaTitle, metaDescription } =
      req.body;

    let slug;
    if (name) {
      slug = name
        .toLowerCase()
        .replace(/[^a-z0-9]+/g, '-')
        .replace(/(^-|-$)/g, '');
    }

    const category = await prisma.category.update({
      where: { id },
      data: {
        name,
        slug,
        description,
        image,
        parentId,
        metaTitle,
        metaDescription,
      },
    });

    res.json({
      status: true,
      message: 'Category updated successfully',
      data: category,
    });
  } catch (error) {
    next(error);
  }
};

exports.deleteCategory = async (req, res, next) => {
  try {
    const { id } = req.params;

    await prisma.category.delete({
      where: { id },
    });

    res.json({
      status: true,
      message: 'Category deleted successfully',
    });
  } catch (error) {
    next(error);
  }
};

exports.toggleCategoryStatus = async (req, res, next) => {
  try {
    const { id } = req.params;
    const { isActive } = req.body;

    // 1️⃣ Update parent category
    const parentCategory = await prisma.category.update({
      where: { id },
      data: { isActive },
    });

    // 2️⃣ If parent is being deactivated, also deactivate all children recursively
    if (!isActive) {
      const deactivateChildren = async parentId => {
        const children = await prisma.category.findMany({
          where: { parentId },
        });

        for (const child of children) {
          await prisma.category.update({
            where: { id: child.id },
            data: { isActive: false },
          });
          // Recursive call for nested subcategories
          await deactivateChildren(child.id);
        }
      };

      await deactivateChildren(id);
    }

    res.json({
      status: true,
      message: `Category ${isActive ? 'activated' : 'deactivated'} successfully`,
      data: parentCategory,
    });
  } catch (error) {
    next(error);
  }
};

exports.reorderCategories = async (req, res) => {
  const { orders } = req.body;

  await Promise.all(
    orders.map(item =>
      prisma.category.update({
        where: { id: item.id },
        data: { sequence: item.sequence },
      })
    )
  );

  res.json({
    status: true,
    message: 'Category order updated',
  });
};

exports.getCategoryHierarchy = async (req, res, next) => {
  try {
    // 1. Fetch all categories
    const categories = await prisma.category.findMany({
      orderBy: { name: 'asc' },
    });

    // 2. Convert array to a lookup map
    const lookup = {};
    categories.forEach(cat => {
      lookup[cat.id] = { ...cat, children: [] };
    });

    const hierarchy = [];

    // 3. Build hierarchical structure
    categories.forEach(cat => {
      if (cat.parentId) {
        lookup[cat.parentId].children.push(lookup[cat.id]);
      } else {
        hierarchy.push(lookup[cat.id]);
      }
    });

    res.status(200).json({
      // statusCode: 200,
      status: true,
      message: 'Category hierarchy fetched successfully',
      data: hierarchy,
    });
  } catch (error) {
    next(error);
  }
};

exports.getCategoryById = async (req, res) => {
  try {
    const { id } = req.params;

    if (!id) {
      return res.status(400).json({
        success: false,
        message: 'Category ID is required',
      });
    }

    const category = await prisma.category.findUnique({
      where: {
        id: id, // ✅ PASS THE ACTUAL STRING VALUE
      },
    });

    if (!category) {
      return res.status(404).json({
        success: false,
        message: 'Category not found',
      });
    }

    return res.status(200).json({
      success: true,
      message: 'Category details fetched successfully',
      data: category,
    });
  } catch (error) {
    console.error('Get category by id error:', error);

    return res.status(500).json({
      success: false,
      message: 'Error fetching category',
    });
  }
};