import fs from 'fs';
import path from 'path';
import matter from 'gray-matter';
import { mapSlugToFileSlug } from './slugs';

export interface ProductFrontmatter {
  title: string;
  sku: string;
  description: string;
  categories: string[];
  images: string[];
  locale: string;
}

export interface ProductMdx {
  slug: string;
  frontmatter: ProductFrontmatter;
  content: string;
}

export async function getProductMetadata(
  slug: string,
  locale: string,
): Promise<Partial<ProductMdx> | null> {
  // Map translated slug to file slug
  const fileSlug = await mapSlugToFileSlug(slug, locale);
  const productsDir = path.join(process.cwd(), 'data', 'products', locale);

  if (!fs.existsSync(productsDir)) return null;

  // Recursive search for the file
  const findFile = (dir: string): string | null => {
    const files = fs.readdirSync(dir);
    for (const file of files) {
      const fullPath = path.join(dir, file);
      const stat = fs.statSync(fullPath);
      if (stat.isDirectory()) {
        const found = findFile(fullPath);
        if (found) return found;
      } else if (file === `${fileSlug}.mdx` || file === `${fileSlug}-2.mdx`) {
        return fullPath;
      }
    }
    return null;
  };

  let filePath = findFile(productsDir);

  if (!filePath && locale !== 'en') {
    // Fallback to English
    const enProductsDir = path.join(process.cwd(), 'data', 'products', 'en');
    if (fs.existsSync(enProductsDir)) {
      filePath = findFile(enProductsDir);
    }
  }

  if (filePath && fs.existsSync(filePath)) {
    const fileContent = fs.readFileSync(filePath, 'utf8');
    const { data } = matter(fileContent);

    // Filter out products without images to match getProductBySlug behavior
    if (!data.images || data.images.length === 0 || !data.images[0]) {
      return null;
    }

    return {
      slug: fileSlug,
      frontmatter: {
        ...data,
        isFallback: filePath.includes('/en/'),
      } as any,
    };
  }

  return null;
}

export async function getProductBySlug(slug: string, locale: string): Promise<ProductMdx | null> {
  // Map translated slug to file slug
  const fileSlug = await mapSlugToFileSlug(slug, locale);
  const productsDir = path.join(process.cwd(), 'data', 'products', locale);

  if (!fs.existsSync(productsDir)) return null;

  // Recursive search for the file
  const findFile = (dir: string): string | null => {
    const files = fs.readdirSync(dir);
    for (const file of files) {
      const fullPath = path.join(dir, file);
      const stat = fs.statSync(fullPath);
      if (stat.isDirectory()) {
        const found = findFile(fullPath);
        if (found) return found;
      } else if (file === `${fileSlug}.mdx` || file === `${fileSlug}-2.mdx`) {
        return fullPath;
      }
    }
    return null;
  };

  let filePath = findFile(productsDir);
  let isFallback = false;

  if (!filePath && locale !== 'en') {
    // Fallback to English
    const enProductsDir = path.join(process.cwd(), 'data', 'products', 'en');
    if (fs.existsSync(enProductsDir)) {
      filePath = findFile(enProductsDir);
      if (filePath) isFallback = true;
    }
  }

  if (filePath && fs.existsSync(filePath)) {
    const fileContent = fs.readFileSync(filePath, 'utf8');
    const { data, content } = matter(fileContent);
    const product = {
      slug: fileSlug,
      frontmatter: {
        ...data,
        isFallback,
      } as any,
      content,
    };

    // Filter out products without images
    if (
      !product.frontmatter.images ||
      product.frontmatter.images.length === 0 ||
      !product.frontmatter.images[0]
    ) {
      return null;
    }

    return product;
  }

  return null;
}

export async function getAllProductSlugs(locale: string): Promise<string[]> {
  const productsDir = path.join(process.cwd(), 'data', 'products', locale);
  if (!fs.existsSync(productsDir)) return [];

  const slugs: string[] = [];
  const walk = (dir: string) => {
    const files = fs.readdirSync(dir);
    for (const file of files) {
      const fullPath = path.join(dir, file);
      const stat = fs.statSync(fullPath);
      if (stat.isDirectory()) {
        walk(fullPath);
      } else if (file.endsWith('.mdx')) {
        slugs.push(file.replace(/\.mdx$/, ''));
      }
    }
  };

  walk(productsDir);
  return slugs;
}

export async function getAllProducts(locale: string): Promise<ProductMdx[]> {
  const slugs = await getAllProductSlugs(locale);
  let allSlugs = slugs;

  if (locale !== 'en') {
    const enSlugs = await getAllProductSlugs('en');
    allSlugs = Array.from(new Set([...slugs, ...enSlugs]));
  }

  const products = await Promise.all(allSlugs.map((slug) => getProductBySlug(slug, locale)));
  return products.filter((p): p is ProductMdx => p !== null);
}

export async function getAllProductsMetadata(locale: string): Promise<Partial<ProductMdx>[]> {
  const slugs = await getAllProductSlugs(locale);
  let allSlugs = slugs;

  if (locale !== 'en') {
    const enSlugs = await getAllProductSlugs('en');
    allSlugs = Array.from(new Set([...slugs, ...enSlugs]));
  }

  const metadata = await Promise.all(allSlugs.map((slug) => getProductMetadata(slug, locale)));
  return metadata.filter((m): m is Partial<ProductMdx> => m !== null);
}