import fs from 'fs';
import path from 'path';
import { bold, cyan, gray, green, red, yellow } from 'kleur/colors';
import fetch from 'node-fetch';
import prompts from 'prompts';
import degit from 'degit';
import yargs from 'yargs-parser';
import { FRAMEWORKS, COUNTER_COMPONENTS } from './frameworks.js';
import { TEMPLATES } from './templates.js';
import { createConfig } from './config.js';

// NOTE: In the v7.x version of npm, the default behavior of `npm init` was changed
// to no longer require `--` to pass args and instead pass `--` directly to us. This
// broke our arg parser, since `--` is a special kind of flag. Filtering for `--` here
// fixes the issue so that create-astro now works on all npm version.
const cleanArgv = process.argv.filter((arg) => arg !== '--');
const args = yargs(cleanArgv, { array: ['renderers'] });
prompts.override(args);

export function mkdirp(dir: string) {
	try {
		fs.mkdirSync(dir, { recursive: true });
	} catch (e: any) {
		if (e.code === 'EEXIST') return;
		throw e;
	}
}

const { version } = JSON.parse(fs.readFileSync(new URL('../package.json', import.meta.url), 'utf-8'));

const POSTPROCESS_FILES = ['package.json', 'astro.config.mjs', 'CHANGELOG.md']; // some files need processing after copying.

export async function main() {
	console.log(`\n${bold('Welcome to Astro!')} ${gray(`(create-astro v${version})`)}`);
	console.log(`If you encounter a problem, visit ${cyan('https://github.com/withastro/astro/issues')} to search or file a new issue.\n`);

	console.log(`${green(`>`)} ${gray(`Prepare for liftoff.`)}`);
	console.log(`${green(`>`)} ${gray(`Gathering mission details...`)}`);

	const cwd = args['_'][2] || '.';
	if (fs.existsSync(cwd)) {
		if (fs.readdirSync(cwd).length > 0) {
			const response = await prompts({
				type: 'confirm',
				name: 'forceOverwrite',
				message: 'Directory not empty. Continue [force overwrite]?',
				initial: false,
			});
			if (!response.forceOverwrite) {
				process.exit(1);
			}
			mkdirp(cwd);
		}
	} else {
		mkdirp(cwd);
	}

	const options = /** @type {import('./types/internal').Options} */ await prompts([
		{
			type: 'select',
			name: 'template',
			message: 'Which app template would you like to use?',
			choices: TEMPLATES,
		},
	]);

	if (!options.template) {
		process.exit(1);
	}

	const hash = args.commit ? `#${args.commit}` : '';

	const templateTarget = options.template.includes('/') ? options.template : `withastro/astro/examples/${options.template}#latest`;

	const emitter = degit(`${templateTarget}${hash}`, {
		cache: false,
		force: true,
		verbose: false,
	});

	const selectedTemplate = TEMPLATES.find((template) => template.value === options.template);
	let renderers: string[] = [];

	if (selectedTemplate?.renderers === true) {
		const result = /** @type {import('./types/internal').Options} */ await prompts([
			{
				type: 'multiselect',
				name: 'renderers',
				message: 'Which frameworks would you like to use?',
				choices: FRAMEWORKS,
			},
		]);
		renderers = result.renderers;
	} else if (selectedTemplate?.renderers && Array.isArray(selectedTemplate.renderers) && selectedTemplate.renderers.length) {
		renderers = selectedTemplate.renderers;
		const titles = renderers.map((renderer) => FRAMEWORKS.find((item) => item.value === renderer)?.title).join(', ');
		console.log(`${green(`✔`)} ${bold(`Using template's default renderers`)} ${gray('›')} ${titles}`);
	}

	// Copy
	try {
		// emitter.on('info', info => { console.log(info.message) });
		console.log(`${green(`>`)} ${gray(`Copying project files...`)}`);
		await emitter.clone(cwd);
	} catch (err: any) {
		// degit is compiled, so the stacktrace is pretty noisy. Just report the message.
		console.error(red(err.message));

		// Warning for issue #655
		if (err.message === 'zlib: unexpected end of file') {
			console.log(yellow("This seems to be a cache related problem. Remove the folder '~/.degit/github/snowpackjs' to fix this error."));
			console.log(yellow('For more information check out this issue: https://github.com/withastro/astro/issues/655'));
		}

		// Helpful message when encountering the "could not find commit hash for ..." error
		if (err.code === 'MISSING_REF') {
			console.log(yellow("This seems to be an issue with degit. Please check if you have 'git' installed on your system, and install it if you don't have (https://git-scm.com)."));
			console.log(yellow("If you do have 'git' installed, please file a new issue here: https://github.com/withastro/astro/issues"));
		}
		process.exit(1);
	}

	// Post-process in parallel
	await Promise.all(
		POSTPROCESS_FILES.map(async (file) => {
			const fileLoc = path.resolve(path.join(cwd, file));

			switch (file) {
				case 'CHANGELOG.md': {
					if (fs.existsSync(fileLoc)) {
						await fs.promises.unlink(fileLoc);
					}
					break;
				}
				case 'astro.config.mjs': {
					if (selectedTemplate?.renderers !== true) {
						break;
					}
					await fs.promises.writeFile(fileLoc, createConfig({ renderers }));
					break;
				}
				case 'package.json': {
					const packageJSON = JSON.parse(await fs.promises.readFile(fileLoc, 'utf8'));
					delete packageJSON.snowpack; // delete snowpack config only needed in monorepo (can mess up projects)
					// Fetch latest versions of selected renderers
					const rendererEntries = (await Promise.all(
						['astro', ...renderers].map((renderer: string) =>
							fetch(`https://registry.npmjs.org/${renderer}/latest`)
								.then((res: any) => res.json())
								.then((res: any) => [renderer, `^${res['version']}`])
						)
					)) as any;
					packageJSON.devDependencies = { ...(packageJSON.devDependencies ?? {}), ...Object.fromEntries(rendererEntries) };
					await fs.promises.writeFile(fileLoc, JSON.stringify(packageJSON, undefined, 2));
					break;
				}
			}
		})
	);

	// Inject framework components into starter template
	if (selectedTemplate?.value === 'starter') {
		let importStatements: string[] = [];
		let components: string[] = [];
		await Promise.all(
			renderers.map(async (renderer) => {
				const component = COUNTER_COMPONENTS[renderer as keyof typeof COUNTER_COMPONENTS];
				const componentName = path.basename(component.filename, path.extname(component.filename));
				const absFileLoc = path.resolve(cwd, component.filename);
				importStatements.push(`import ${componentName} from '${component.filename.replace(/^src/, '..')}';`);
				components.push(`<${componentName} client:visible />`);
				await fs.promises.writeFile(absFileLoc, component.content);
			})
		);

		const pageFileLoc = path.resolve(path.join(cwd, 'src', 'pages', 'index.astro'));
		const content = (await fs.promises.readFile(pageFileLoc)).toString();
		const newContent = content
			.replace(/^(\s*)\/\* ASTRO\:COMPONENT_IMPORTS \*\//gm, (_, indent) => {
				return indent + importStatements.join('\n');
			})
			.replace(/^(\s*)<!-- ASTRO:COMPONENT_MARKUP -->/gm, (_, indent) => {
				return components.map((ln) => indent + ln).join('\n');
			});
		await fs.promises.writeFile(pageFileLoc, newContent);
	}

	console.log(bold(green('✔') + ' Done!'));

	console.log('\nNext steps:');
	let i = 1;

	const relative = path.relative(process.cwd(), cwd);
	if (relative !== '') {
		console.log(`  ${i++}: ${bold(cyan(`cd ${relative}`))}`);
	}

	console.log(`  ${i++}: ${bold(cyan('npm install'))} (or pnpm install, yarn, etc)`);
	console.log(`  ${i++}: ${bold(cyan('git init && git add -A && git commit -m "Initial commit"'))} (optional step)`);
	console.log(`  ${i++}: ${bold(cyan('npm run dev'))} (or pnpm, yarn, etc)`);

	console.log(`\nTo close the dev server, hit ${bold(cyan('Ctrl-C'))}`);
	console.log(`\nStuck? Visit us at ${cyan('https://astro.build/chat')}\n`);
}