'use server';

import { db } from '@/lib/db';
import { revalidatePath } from 'next/cache';

const INITIAL_CATEGORIES = [
  'Next.js',
  'React',
  'Python & AI',
  'Tailwind CSS',
  'Docker & DevOps',
];

export async function getCategories() {
  try {
    if (!db || !(db as any).category) {
      console.error('db.category is not initialized yet');
      return INITIAL_CATEGORIES.map((name) => ({ id: name, name, slug: name.toLowerCase() }));
    }

    let categories = await db.category.findMany({
      orderBy: { name: 'asc' },
    });

    if (categories.length === 0) {
      // Seed default categories if database has none
      for (const name of INITIAL_CATEGORIES) {
        const slug = name
          .toLowerCase()
          .replace(/[^\w\s-]/g, '')
          .replace(/[\s_-]+/g, '-');
        await db.category.upsert({
          where: { slug },
          update: { name },
          create: { name, slug },
        }).catch(err => console.error('Failed seeding category:', name, err));
      }

      categories = await db.category.findMany({
        orderBy: { name: 'asc' },
      });
    }

    return categories;
  } catch (error) {
    console.error('Error fetching categories:', error);
    return INITIAL_CATEGORIES.map((name) => ({ id: name, name, slug: name.toLowerCase() }));
  }
}

export async function createCategory(name: string) {
  try {
    const trimmed = name.trim();
    if (!trimmed) return { success: false, error: 'Category name cannot be empty' };

    const slug = trimmed
      .toLowerCase()
      .replace(/[^\w\s-]/g, '')
      .replace(/[\s_-]+/g, '-') + '-' + Date.now().toString().slice(-4);

    const newCategory = await db.category.create({
      data: {
        name: trimmed,
        slug,
      },
    });

    revalidatePath('/[locale]');
    revalidatePath('/[locale]/lessons');
    revalidatePath('/[locale]/admin');
    return { success: true, category: newCategory };
  } catch (error: any) {
    console.error('Error creating category:', error);
    return { success: false, error: error.message || 'Failed to create category' };
  }
}

export async function updateCategory(id: string, name: string) {
  try {
    const trimmed = name.trim();
    if (!trimmed) return { success: false, error: 'Category name cannot be empty' };

    const slug = trimmed
      .toLowerCase()
      .replace(/[^\w\s-]/g, '')
      .replace(/[\s_-]+/g, '-') + '-' + Date.now().toString().slice(-4);

    const updatedCategory = await db.category.updateMany({
      where: {
        OR: [{ id }, { name: id }, { slug: id }],
      },
      data: {
        name: trimmed,
        slug,
      },
    });

    revalidatePath('/[locale]');
    revalidatePath('/[locale]/lessons');
    revalidatePath('/[locale]/admin');
    return { success: true, count: updatedCategory.count };
  } catch (error: any) {
    console.error('Error updating category:', error);
    return { success: false, error: error.message || 'Failed to update category' };
  }
}

export async function deleteCategory(id: string) {
  try {
    if (!db || !(db as any).category) {
      return { success: false, error: 'Category database table is not ready' };
    }

    await db.category.deleteMany({
      where: {
        OR: [{ id }, { name: id }, { slug: id }],
      },
    });

    revalidatePath('/[locale]');
    revalidatePath('/[locale]/dersler');
    revalidatePath('/[locale]/admin');
    return { success: true };
  } catch (error: any) {
    console.error('Error deleting category:', error);
    return { success: false, error: error.message || 'Failed to delete category' };
  }
}