import fs from 'node:fs';
import { mkdirp } from '../../../utils/filesystem.js';
import { find_deps, resolve_symlinks } from './utils.js';
import { s } from '../../../utils/misc.js';
import { normalizePath } from 'vite';

/**
 * @param {string} out
 * @param {import('types').ValidatedKitConfig} kit
 * @param {import('types').ManifestData} manifest_data
 * @param {import('vite').Manifest} server_manifest
 * @param {import('vite').Manifest | null} client_manifest
 * @param {import('rollup').OutputAsset[] | null} css
 */
export function build_server_nodes(out, kit, manifest_data, server_manifest, client_manifest, css) {
	mkdirp(`${out}/server/nodes`);
	mkdirp(`${out}/server/stylesheets`);

	const stylesheet_lookup = new Map();

	if (css) {
		css.forEach((asset) => {
			if (asset.source.length < kit.inlineStyleThreshold) {
				const index = stylesheet_lookup.size;
				const file = `${out}/server/stylesheets/${index}.js`;

				fs.writeFileSync(file, `// ${asset.fileName}\nexport default ${s(asset.source)};`);
				stylesheet_lookup.set(asset.fileName, index);
			}
		});
	}

	manifest_data.nodes.forEach((node, i) => {
		/** @type {string[]} */
		const imports = [];

		// String representation of
		/** @type {import('types').SSRNode} */
		/** @type {string[]} */
		const exports = [`export const index = ${i};`];

		/** @type {string[]} */
		const imported = [];

		/** @type {string[]} */
		const stylesheets = [];

		/** @type {string[]} */
		const fonts = [];

		if (node.component && client_manifest) {
			exports.push(
				'let component_cache;',
				`export const component = async () => component_cache ??= (await import('../${
					resolve_symlinks(server_manifest, node.component).chunk.file
				}')).default;`
			);
		}

		if (node.universal) {
			imports.push(`import * as universal from '../${server_manifest[node.universal].file}';`);
			exports.push('export { universal };');
			exports.push(`export const universal_id = ${s(node.universal)};`);
		}

		if (node.server) {
			imports.push(`import * as server from '../${server_manifest[node.server].file}';`);
			exports.push('export { server };');
			exports.push(`export const server_id = ${s(node.server)};`);
		}

		if (client_manifest && (node.universal || node.component)) {
			const entry = find_deps(
				client_manifest,
				`${normalizePath(kit.outDir)}/generated/client-optimized/nodes/${i}.js`,
				true
			);

			imported.push(...entry.imports);
			stylesheets.push(...entry.stylesheets);
			fonts.push(...entry.fonts);
		}

		exports.push(
			`export const imports = ${s(imported)};`,
			`export const stylesheets = ${s(stylesheets)};`,
			`export const fonts = ${s(fonts)};`
		);

		/** @type {string[]} */
		const styles = [];

		stylesheets.forEach((file) => {
			if (stylesheet_lookup.has(file)) {
				const index = stylesheet_lookup.get(file);
				const name = `stylesheet_${index}`;
				imports.push(`import ${name} from '../stylesheets/${index}.js';`);
				styles.push(`\t${s(file)}: ${name}`);
			}
		});

		if (styles.length > 0) {
			exports.push(`export const inline_styles = () => ({\n${styles.join(',\n')}\n});`);
		}

		fs.writeFileSync(
			`${out}/server/nodes/${i}.js`,
			`${imports.join('\n')}\n\n${exports.join('\n')}\n`
		);
	});
}