import * as path from 'path';
import * as fs from 'fs';
import { rollup } from 'rollup';
import virtual from '@rollup/plugin-virtual';
import glob from 'tiny-glob/sync.js';
import { clear_loops, flush, set_now, set_raf } from '../../internal';

import {
	assert,
	showOutput,
	loadConfig,
	loadSvelte,
	cleanRequireCache,
	env,
	setupHtmlEqual,
	mkdirp
} from '../helpers';

let svelte$;
let svelte;

let compileOptions = null;
let compile = null;

const sveltePath = process.cwd().split('\\').join('/');

let unhandled_rejection = false;
process.on('unhandledRejection', err => {
	unhandled_rejection = err;
});

describe('runtime', () => {
	before(() => {
		svelte = loadSvelte(false);
		svelte$ = loadSvelte(true);

		require.extensions['.svelte'] = function(module, filename) {
			const options = Object.assign({
				filename
			}, compileOptions);

			const { js: { code } } = compile(fs.readFileSync(filename, 'utf-8').replace(/\r/g, ''), options);

			return module._compile(code, filename);
		};

		return setupHtmlEqual();
	});

	const failed = new Set();

	function runTest(dir, hydrate) {
		if (dir[0] === '.') return;

		const config = loadConfig(`${__dirname}/samples/${dir}/_config.js`);
		const solo = config.solo || /\.solo/.test(dir);

		if (hydrate && config.skip_if_hydrate) return;

		if (solo && process.env.CI) {
			throw new Error('Forgot to remove `solo: true` from test');
		}

		(config.skip ? it.skip : solo ? it.only : it)(`${dir} ${hydrate ? '(with hydration)' : ''}`, () => {
			if (failed.has(dir)) {
				// this makes debugging easier, by only printing compiled output once
				throw new Error('skipping test, already failed');
			}

			unhandled_rejection = null;

			compile = (config.preserveIdentifiers ? svelte : svelte$).compile;

			const cwd = path.resolve(`${__dirname}/samples/${dir}`);

			compileOptions = config.compileOptions || {};
			compileOptions.format = 'cjs';
			compileOptions.sveltePath = sveltePath;
			compileOptions.hydratable = hydrate;
			compileOptions.immutable = config.immutable;
			compileOptions.accessors = 'accessors' in config ? config.accessors : true;

			cleanRequireCache();

			let mod;
			let SvelteComponent;

			let unintendedError = null;

			const window = env();

			glob('**/*.svelte', { cwd }).forEach(file => {
				if (file[0] === '_') return;

				const dir  = `${cwd}/_output/${hydrate ? 'hydratable' : 'normal'}`;
				const out = `${dir}/${file.replace(/\.svelte$/, '.js')}`;

				if (fs.existsSync(out)) {
					fs.unlinkSync(out);
				}

				mkdirp(dir);

				try {
					const { js } = compile(
						fs.readFileSync(`${cwd}/${file}`, 'utf-8').replace(/\r/g, ''),
						{
							...compileOptions,
							filename: file
						}
					);

					fs.writeFileSync(out, js.code);
				} catch (err) {
					// do nothing
				}
			});

			return Promise.resolve()
				.then(() => {
					// hack to support transition tests
					clear_loops();

					const raf = {
						time: 0,
						callback: null,
						tick: now => {
							raf.time = now;
							if (raf.callback) raf.callback();
						}
					};
					set_now(() => raf.time);
					set_raf(cb => {
						raf.callback = () => {
							raf.callback = null;
							cb(raf.time);
							flush();
						};
					});

					try {
						mod = require(`./samples/${dir}/main.svelte`);
						SvelteComponent = mod.default;
					} catch (err) {
						showOutput(cwd, compileOptions, compile); // eslint-disable-line no-console
						throw err;
					}

					if (config.before_test) config.before_test();

					// Put things we need on window for testing
					window.SvelteComponent = SvelteComponent;

					const target = window.document.querySelector('main');

					const warnings = [];
					const warn = console.warn;
					console.warn = warning => {
						warnings.push(warning);
					};

					const options = Object.assign({}, {
						target,
						hydrate,
						props: config.props,
						intro: config.intro
					}, config.options || {});

					const component = new SvelteComponent(options);

					console.warn = warn;

					if (config.error) {
						unintendedError = true;
						throw new Error('Expected a runtime error');
					}

					if (config.warnings) {
						assert.deepEqual(warnings, config.warnings);
					} else if (warnings.length) {
						unintendedError = true;
						throw new Error('Received unexpected warnings');
					}

					if (config.html) {
						assert.htmlEqual(target.innerHTML, config.html);
					}

					if (config.test) {
						return Promise.resolve(config.test({
							assert,
							component,
							mod,
							target,
							window,
							raf,
							compileOptions
						})).then(() => {
							component.$destroy();

							if (unhandled_rejection) {
								throw unhandled_rejection;
							}
						});
					} else {
						component.$destroy();
						assert.htmlEqual(target.innerHTML, '');

						if (unhandled_rejection) {
							throw unhandled_rejection;
						}
					}
				})
				.catch(err => {
					if (config.error && !unintendedError) {
						if (typeof config.error === 'function') {
							config.error(assert, err);
						} else {
							assert.equal(err.message, config.error);
						}
					} else {
						throw err;
					}
				}).catch(err => {
					failed.add(dir);
					showOutput(cwd, compileOptions, compile); // eslint-disable-line no-console
					throw err;
				})
				.catch(err => {
					// print a clickable link to open the directory
					err.stack += `\n\ncmd-click: ${path.relative(process.cwd(), cwd)}/main.svelte`;
					throw err;
				})
				.then(() => {
					if (config.show) {
						showOutput(cwd, compileOptions, compile);
					}

					flush();

					if (config.after_test) config.after_test();
				});
		});
	}

	fs.readdirSync(`${__dirname}/samples`).forEach(dir => {
		runTest(dir, false);
		runTest(dir, true);
	});

	async function create_component(src = '<div></div>') {
		const { js } = svelte$.compile(src, {
			format: 'esm',
			name: 'SvelteComponent',
			dev: true
		});

		const bundle = await rollup({
			input: 'main.js',
			plugins: [
				virtual({
					'main.js': js.code
				}),
				{
					name: 'svelte-packages',
					resolveId: (importee) => {
						if (importee.startsWith('svelte/')) {
							return importee.replace('svelte', process.cwd()) + '/index.mjs';
						}
					}
				}
			]
		});

		const result = await bundle.generate({
			format: 'iife',
			name: 'App'
		});

		return eval(
			`(function () { ${result.output[0].code}; return App; }())`
		);
	}

	it('fails if options.target is missing in dev mode', async () => {
		const App = await create_component();

		assert.throws(() => {
			new App();
		}, /'target' is a required option/);
	});

	it('fails if options.hydrate is true but the component is non-hydratable', async () => {
		const App = await create_component();

		assert.throws(() => {
			new App({
				target: { childNodes: [] },
				hydrate: true
			});
		}, /options.hydrate only works if the component was compiled with the `hydratable: true` option/);
	});
});