import {
	beforeAll,
	afterAll,
	afterEach,
	beforeEach,
	describe,
	expect,
	it, vi,
} from 'vitest';
import {
	tmpdir
} from 'os';
import {
	mkdtemp,
	rm,
	writeFile,
} from 'fs/promises';
import {
	join
} from 'path';
import {request} from 'http';
import {constants} from 'http2';
import {Backend, dataSources} from '../../../src/backend';
import { application, resource, validation as v, Resource } from '../../../src/common';
import { autoIncrement } from '../../fixtures';
import {createTestClient, TestClient} from '../../utils';
import {DataSource} from '../../../src/backend/data-source';

const PORT = 3001;
const HOST = '127.0.0.1';
const BASE_PATH = '/api';
const ACCEPT = 'application/json';
const ACCEPT_LANGUAGE = 'en';
const ACCEPT_CHARSET = 'utf-8';
const CONTENT_TYPE_CHARSET = 'utf-8';
const CONTENT_TYPE = ACCEPT;

class DummyDataSource implements DataSource {
	private resource?: { dataSource?: unknown };

	create(): Promise<never> {
		throw new Error();
	}

	delete(): Promise<never> {
		throw new Error();
	}

	emplace(): Promise<never> {
		throw new Error();
	}

	getById(): Promise<never> {
		throw new Error();
	}

	newId(): Promise<never> {
		throw new Error();
	}

	getMultiple(): Promise<never> {
		throw new Error();
	}

	getSingle(): Promise<never> {
		throw new Error();
	}

	getTotalCount(): Promise<never> {
		throw new Error();
	}

	async initialize(): Promise<void> {}

	patch(): Promise<never> {
		throw new Error();
	}

	prepareResource(rr: unknown) {
		this.resource = rr as unknown as { dataSource: DummyDataSource };
		this.resource.dataSource = this;
	}
}

describe('error handling', () => {
	let client: TestClient;
	beforeEach(() => {
		client = createTestClient({
			host: HOST,
			port: PORT,
		})
			.acceptMediaType(ACCEPT)
			.acceptLanguage(ACCEPT_LANGUAGE)
			.acceptCharset(ACCEPT_CHARSET)
			.contentType(CONTENT_TYPE)
			.contentCharset(CONTENT_TYPE_CHARSET);
	});

	describe('on internal errors', () => {
		let baseDir: string;
		beforeAll(async () => {
			try {
				baseDir = await mkdtemp(join(tmpdir(), 'yasumi-'));
			} catch {
				// noop
			}
		});
		afterAll(async () => {
			try {
				await rm(baseDir, {
					recursive: true,
				});
			} catch {
				// noop
			}
		});

		let Piano: Resource;
		beforeEach(() => {
			Piano = resource(v.object(
				{
					brand: v.string()
				},
				v.never()
			))
				.name('Piano' as const)
				.route('pianos' as const)
				.id('id' as const, {
					generationStrategy: autoIncrement,
					serialize: (id) => id?.toString() ?? '0',
					deserialize: (id) => Number.isFinite(Number(id)) ? Number(id) : 0,
					schema: v.number(),
				});
		});

		let dataSource: DataSource;
		let backend: Backend;
		let server: ReturnType<Backend['createHttpServer']>;
		beforeEach(() => {
			const app = application({
				name: 'piano-service',
			})
				.resource(Piano);

			dataSource = new DummyDataSource();

			backend = app.createBackend({
				dataSource,
			});

			server = backend.createHttpServer({
				basePath: BASE_PATH
			});

			return new Promise((resolve, reject) => {
				server.on('error', (err) => {
					reject(err);
				});

				server.on('listening', () => {
					resolve();
				});

				server.listen({
					port: PORT
				});
			});
		});

		afterEach(() => new Promise((resolve, reject) => {
			server.close((err) => {
				if (err) {
					reject(err);
				}

				resolve();
			});
		}));

		describe.skip('serving collections', () => {
			beforeEach(() => {
				Piano.canFetchCollection();
				return new Promise((resolve) => {
					setTimeout(() => {
						resolve();
					});
				});
			});

			afterEach(() => {
				Piano.canFetchCollection(false);
			});

			it('throws on query', async () => {
				const [res] = await client({
					method: 'GET',
					path: `${BASE_PATH}/pianos`,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_INTERNAL_SERVER_ERROR);
				expect(res).toHaveProperty('statusMessage', 'Unable To Fetch Piano Collection');
			});

			it('throws on HEAD method', async () => {
				const [res] = await client({
					method: 'HEAD',
					path: `${BASE_PATH}/pianos`,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_INTERNAL_SERVER_ERROR);
				expect(res).toHaveProperty('statusMessage', 'Unable To Fetch Piano Collection');
			});
		});

		describe('serving items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canFetchItem();
				return new Promise((resolve) => {
					setTimeout(() => {
						resolve();
					});
				});
			});

			afterEach(() => {
				Piano.canFetchItem(false);
			});

			it('throws on query', async () => {
				const [res] = await client({
					method: 'GET',
					path: `${BASE_PATH}/pianos/2`,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_INTERNAL_SERVER_ERROR);
				expect(res).toHaveProperty('statusMessage', 'Unable To Fetch Piano');
			});

			it('throws on HEAD method', async () => {
				const [res] = await client({
					method: 'HEAD',
					path: `${BASE_PATH}/pianos/2`,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_INTERNAL_SERVER_ERROR);
				expect(res).toHaveProperty('statusMessage', 'Unable To Fetch Piano');
			});

			it('throws on item not found', async () => {
				const getById = vi.spyOn(DummyDataSource.prototype, 'getById');
				getById.mockResolvedValueOnce(null as never);

				const [res] = await client({
					method: 'GET',
					path: `${BASE_PATH}/pianos/2`,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_NOT_FOUND);
			});

			it('throws on item not found on HEAD method', async () => {
				const getById = vi.spyOn(DummyDataSource.prototype, 'getById');
				getById.mockResolvedValueOnce(null as never);

				const [res] = await client({
					method: 'HEAD',
					path: `${BASE_PATH}/pianos/2`,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_NOT_FOUND);
			});
		});

		describe('creating items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			const newData = {
				brand: 'K. Kawai'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canCreate();
			});

			afterEach(() => {
				Piano.canCreate(false);
			});

			it('throws on error assigning ID', async () => {
				const [res] = await client({
					method: 'POST',
					path: `${BASE_PATH}/pianos`,
					body: newData,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_INTERNAL_SERVER_ERROR);
				expect(res).toHaveProperty('statusMessage', 'Unable To Assign ID From Piano Data Source');
			});

			it('throws on error creating resource', async () => {
				const getById = vi.spyOn(DummyDataSource.prototype, 'newId');
				getById.mockResolvedValueOnce(data.id as never);

				const [res] = await client({
					method: 'POST',
					path: `${BASE_PATH}/pianos`,
					body: newData,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_INTERNAL_SERVER_ERROR);
				expect(res).toHaveProperty('statusMessage', 'Unable To Create Piano');
			});
		});

		describe.skip('patching items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			const newData = {
				brand: 'K. Kawai'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canPatch();
			});

			afterEach(() => {
				Piano.canPatch(false);
			});

			it('throws on item to patch not found', () => {
				return new Promise<void>((resolve, reject) => {
					const req = request(
						{
							host: HOST,
							port: PORT,
							path: `${BASE_PATH}/pianos/2`,
							method: 'PATCH',
							headers: {
								'Accept': ACCEPT,
								'Accept-Language': ACCEPT_LANGUAGE,
								'Content-Type': `${CONTENT_TYPE}; charset="${CONTENT_TYPE_CHARSET}"`,
							},
						},
						(res) => {
							res.on('error', (err) => {
								reject(err);
							});

							expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_NOT_FOUND);
							resolve();
						},
					);

					req.on('error', (err) => {
						reject(err);
					});

					req.write(JSON.stringify(newData));
					req.end();
				});
			});
		});

		describe.skip('emplacing items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			const newData = {
				id: 1,
				brand: 'K. Kawai'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canEmplace();
			});

			afterEach(() => {
				Piano.canEmplace(false);
			});
		});

		describe.skip('deleting items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canDelete();
				backend.throwsErrorOnDeletingNotFound();
			});

			afterEach(() => {
				Piano.canDelete(false);
				backend.throwsErrorOnDeletingNotFound(false);
			});

			it('throws on item not found', () => {
				return new Promise<void>((resolve, reject) => {
					const req = request(
						{
							host: HOST,
							port: PORT,
							path: `${BASE_PATH}/pianos/2`,
							method: 'DELETE',
							headers: {
								'Accept': ACCEPT,
								'Accept-Language': ACCEPT_LANGUAGE,
							},
						},
						(res) => {
							res.on('error', (err) => {
								reject(err);
							});

							expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_NOT_FOUND);
							resolve();
						},
					);

					req.on('error', (err) => {
						reject(err);
					});

					req.end();
				});
			});
		});
	});

	describe('on data source errors', () => {
		let baseDir: string;
		beforeAll(async () => {
			try {
				baseDir = await mkdtemp(join(tmpdir(), 'yasumi-'));
			} catch {
				// noop
			}
		});
		afterAll(async () => {
			try {
				await rm(baseDir, {
					recursive: true,
				});
			} catch {
				// noop
			}
		});

		let Piano: Resource;
		beforeEach(() => {
			Piano = resource(v.object(
				{
					brand: v.string()
				},
				v.never()
			))
				.name('Piano' as const)
				.route('pianos' as const)
				.id('id' as const, {
					generationStrategy: autoIncrement,
					serialize: (id) => id?.toString() ?? '0',
					deserialize: (id) => Number.isFinite(Number(id)) ? Number(id) : 0,
					schema: v.number(),
				});
		});

		let backend: Backend;
		let server: ReturnType<Backend['createHttpServer']>;
		beforeEach(() => {
			const app = application({
				name: 'piano-service',
			})
				.resource(Piano);

			backend = app.createBackend({
				dataSource: new dataSources.jsonlFile.DataSource(baseDir),
			});

			server = backend.createHttpServer({
				basePath: BASE_PATH
			});

			return new Promise((resolve, reject) => {
				server.on('error', (err) => {
					reject(err);
				});

				server.on('listening', () => {
					resolve();
				});

				server.listen({
					port: PORT
				});
			});
		});

		afterEach(() => new Promise((resolve, reject) => {
			server.close((err) => {
				if (err) {
					reject(err);
				}

				resolve();
			});
		}));

		describe.skip('serving collections', () => {
			beforeEach(() => {
				Piano.canFetchCollection();
				return new Promise((resolve) => {
					setTimeout(() => {
						resolve();
					});
				});
			});

			afterEach(() => {
				Piano.canFetchCollection(false);
			});
		});

		describe('serving items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canFetchItem();
				return new Promise((resolve) => {
					setTimeout(() => {
						resolve();
					});
				});
			});

			afterEach(() => {
				Piano.canFetchItem(false);
			});

			it('throws on item not found', async () => {
				const [res] = await client({
					method: 'GET',
					path: `${BASE_PATH}/pianos/2`,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_NOT_FOUND);
			});

			it('throws on item not found on HEAD method', async () => {
				const [res] = await client({
					method: 'HEAD',
					path: `${BASE_PATH}/pianos/2`,
				});

				expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_NOT_FOUND);
			});
		});

		describe.skip('creating items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			const newData = {
				brand: 'K. Kawai'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canCreate();
			});

			afterEach(() => {
				Piano.canCreate(false);
			});
		});

		describe.skip('patching items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			const newData = {
				brand: 'K. Kawai'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canPatch();
			});

			afterEach(() => {
				Piano.canPatch(false);
			});

			it('throws on item to patch not found', () => {
				return new Promise<void>((resolve, reject) => {
					const req = request(
						{
							host: HOST,
							port: PORT,
							path: `${BASE_PATH}/pianos/2`,
							method: 'PATCH',
							headers: {
								'Accept': ACCEPT,
								'Accept-Language': ACCEPT_LANGUAGE,
								'Content-Type': `${CONTENT_TYPE}; charset="${CONTENT_TYPE_CHARSET}"`,
							},
						},
						(res) => {
							res.on('error', (err) => {
								reject(err);
							});

							expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_NOT_FOUND);
							resolve();
						},
					);

					req.on('error', (err) => {
						reject(err);
					});

					req.write(JSON.stringify(newData));
					req.end();
				});
			});
		});

		describe.skip('emplacing items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			const newData = {
				id: 1,
				brand: 'K. Kawai'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canEmplace();
			});

			afterEach(() => {
				Piano.canEmplace(false);
			});
		});

		describe.skip('deleting items', () => {
			const data = {
				id: 1,
				brand: 'Yamaha'
			};

			beforeEach(async () => {
				const resourcePath = join(baseDir, 'pianos.jsonl');
				await writeFile(resourcePath, JSON.stringify(data));
			});

			beforeEach(() => {
				Piano.canDelete();
				backend.throwsErrorOnDeletingNotFound();
			});

			afterEach(() => {
				Piano.canDelete(false);
				backend.throwsErrorOnDeletingNotFound(false);
			});

			it('throws on item not found', () => {
				return new Promise<void>((resolve, reject) => {
					const req = request(
						{
							host: HOST,
							port: PORT,
							path: `${BASE_PATH}/pianos/2`,
							method: 'DELETE',
							headers: {
								'Accept': ACCEPT,
								'Accept-Language': ACCEPT_LANGUAGE,
							},
						},
						(res) => {
							res.on('error', (err) => {
								reject(err);
							});

							expect(res).toHaveProperty('statusCode', constants.HTTP_STATUS_NOT_FOUND);
							resolve();
						},
					);

					req.on('error', (err) => {
						reject(err);
					});

					req.end();
				});
			});
		});
	});
});