import { fetchCms } from "~/server/utils/cmsApi";

function slugify(text: string): string {
	return text
		.toLowerCase()
		.replace(/\s+/g, "-")
		.replace(/ü/g, "ue")
		.replace(/ä/g, "ae")
		.replace(/ö/g, "oe")
		.replace(/ß/g, "ss");
}

interface ProductData {
	id: number;
	slug?: string;
	updatedAt?: string;
	cover?: { id: number } | { data: { id: number } };
	attributes?: {
		slug: string;
		updatedAt: string;
		cover?: { data: { id: number } };
	};
}

interface CoverData {
	id: number;
	name?: string;
	sort?: number;
	updatedAt?: string;
	attributes?: {
		name: string;
		sort?: number;
		updatedAt: string;
	};
}

interface ApiResponse<T> {
	data: T[];
	meta?: {
		pagination?: {
			total: number;
			pageSize: number;
			pageCount: number;
		};
	};
}

export default defineSitemapEventHandler(async (event) => {
	const config = useRuntimeConfig(event);
	const siteUrl = config.siteUrl || "https://muellerprints-paperwork.com";
	const urls: { loc: string; lastmod?: string; priority?: number }[] = [];
	const allPageSize = 20; // must match notebooks/index.vue pageSize
	const coverPageSize = 24; // must match notebooks/[cover].vue pageSize

	try {
		// Fetch all products for detail page URLs
		const products = await fetchCms<ApiResponse<ProductData>>("/products", {
			query: {
				"pagination[pageSize]": "1000",
				"fields[0]": "slug",
				"fields[1]": "updatedAt",
				"populate[cover][fields][0]": "id"
			}
		});

		// Product detail pages
		for (const product of products.data || []) {
			const slug = product.slug || product.attributes?.slug;
			const updatedAt = product.updatedAt || product.attributes?.updatedAt;

			if (slug) {
				urls.push({
					loc: `${siteUrl}/details/${slug}`,
					lastmod: updatedAt,
					priority: 0.8
				});
			}
		}

		// Fetch promo products count for pagination (matches what the page actually shows)
		const promoProducts = await fetchCms<ApiResponse<ProductData>>("/promo-products", {
			query: {
				"pagination[pageSize]": "1",
				"pagination[page]": "1"
			}
		});
		const totalPromoProducts = promoProducts.meta?.pagination?.total || 0;
		const totalNotebooksPages = Math.ceil(totalPromoProducts / allPageSize);

		// Add /notebooks pagination pages
		for (let page = 2; page <= totalNotebooksPages; page++) {
			urls.push({
				loc: `${siteUrl}/notebooks?page=${page}`,
				priority: 0.7
			});
		}

		// Fetch all covers
		const covers = await fetchCms<ApiResponse<CoverData>>("/product-covers", {
			query: {
				"fields[0]": "name",
				"fields[1]": "sort",
				"fields[2]": "updatedAt"
			}
		});

		// Sort covers by sort field
		const sortedCovers = (covers.data || []).sort((a, b) => {
			const sortA = a.sort ?? a.attributes?.sort ?? 0;
			const sortB = b.sort ?? b.attributes?.sort ?? 0;
			return sortA - sortB;
		});

		// Cover category pages with slugs and pagination
		for (const cover of sortedCovers) {
			const name = cover.name || cover.attributes?.name;
			const updatedAt = cover.updatedAt || cover.attributes?.updatedAt;

			if (name) {
				const slug = slugify(name);

				// Main category page
				urls.push({
					loc: `${siteUrl}/notebooks/${slug}`,
					lastmod: updatedAt,
					priority: 0.7
				});

				// Fetch promo product count for this cover (matches page display)
				const coverId = cover.id;
				const coverPromo = await fetchCms<ApiResponse<ProductData>>("/promo-products", {
					query: {
						"filters[cover]": String(coverId),
						"pagination[pageSize]": "1",
						"pagination[page]": "1"
					}
				});
				const coverTotal = coverPromo.meta?.pagination?.total || 0;
				const coverPageCount = Math.ceil(coverTotal / coverPageSize);

				// Add pagination pages for this category
				for (let page = 2; page <= coverPageCount; page++) {
					urls.push({
						loc: `${siteUrl}/notebooks/${slug}?page=${page}`,
						priority: 0.6
					});
				}
			}
		}
	} catch (error) {
		console.error("Error fetching sitemap data:", error);
	}

	// Static pages
	urls.push(
		{ loc: `${siteUrl}/`, priority: 1.0 },
		{ loc: `${siteUrl}/notebooks`, priority: 0.9 },
		// Info pages
		{ loc: `${siteUrl}/about`, priority: 0.6 },
		{ loc: `${siteUrl}/kontakt`, priority: 0.5 },
		{ loc: `${siteUrl}/anfahrt`, priority: 0.4 },
		{ loc: `${siteUrl}/oeffnungszeiten`, priority: 0.4 },
		// Legal pages
		{ loc: `${siteUrl}/impressum`, priority: 0.2 },
		{ loc: `${siteUrl}/datenschutz`, priority: 0.2 },
		{ loc: `${siteUrl}/agb`, priority: 0.2 },
		{ loc: `${siteUrl}/versand`, priority: 0.3 },
		{ loc: `${siteUrl}/zahlung`, priority: 0.3 }
	);

	return urls;
});