/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

import * as assert from 'assert';
import * as platform from 'vs/base/common/platform';
import * as crypto from 'crypto';
import * as os from 'os';
import * as fs from 'fs';
import * as path from 'vs/base/common/path';
import * as pfs from 'vs/base/node/pfs';
import { URI } from 'vs/base/common/uri';
import { BackupFilesModel } from 'vs/workbench/services/backup/common/backupFileService';
import { TextModel, createTextBufferFactory } from 'vs/editor/common/model/textModel';
import { getRandomTestPath } from 'vs/base/test/node/testUtils';
import { DefaultEndOfLine } from 'vs/editor/common/model';
import { Schemas } from 'vs/base/common/network';
import { IWindowConfiguration } from 'vs/platform/windows/common/windows';
import { FileService } from 'vs/platform/files/common/fileService';
import { NullLogService } from 'vs/platform/log/common/log';
import { DiskFileSystemProvider } from 'vs/platform/files/node/diskFileSystemProvider';
import { NativeWorkbenchEnvironmentService } from 'vs/workbench/services/environment/electron-browser/environmentService';
import { parseArgs, OPTIONS } from 'vs/platform/environment/node/argv';
import { snapshotToString } from 'vs/workbench/services/textfile/common/textfiles';
import { IFileService } from 'vs/platform/files/common/files';
import { hashPath, BackupFileService } from 'vs/workbench/services/backup/node/backupFileService';
import { BACKUPS } from 'vs/platform/environment/common/environment';
import { FileUserDataProvider } from 'vs/workbench/services/userData/common/fileUserDataProvider';
import { VSBuffer } from 'vs/base/common/buffer';

const userdataDir = getRandomTestPath(os.tmpdir(), 'vsctests', 'backupfileservice');
const appSettingsHome = path.join(userdataDir, 'User');
const backupHome = path.join(userdataDir, 'Backups');
const workspacesJsonPath = path.join(backupHome, 'workspaces.json');

const workspaceResource = URI.file(platform.isWindows ? 'c:\\workspace' : '/workspace');
const workspaceBackupPath = path.join(backupHome, hashPath(workspaceResource));
const fooFile = URI.file(platform.isWindows ? 'c:\\Foo' : '/Foo');
const customFile = URI.parse('customScheme://some/path');
const customFileWithFragment = URI.parse('customScheme2://some/path#fragment');
const barFile = URI.file(platform.isWindows ? 'c:\\Bar' : '/Bar');
const fooBarFile = URI.file(platform.isWindows ? 'c:\\Foo Bar' : '/Foo Bar');
const untitledFile = URI.from({ scheme: Schemas.untitled, path: 'Untitled-1' });
const fooBackupPath = path.join(workspaceBackupPath, 'file', hashPath(fooFile));
const barBackupPath = path.join(workspaceBackupPath, 'file', hashPath(barFile));
const untitledBackupPath = path.join(workspaceBackupPath, 'untitled', hashPath(untitledFile));

class TestBackupEnvironmentService extends NativeWorkbenchEnvironmentService {

	constructor(backupPath: string) {
		super({ ...parseArgs(process.argv, OPTIONS), ...{ backupPath, 'user-data-dir': userdataDir } } as IWindowConfiguration, process.execPath, 0);
	}

}

class TestBackupFileService extends BackupFileService {

	readonly fileService: IFileService;

	constructor(workspace: URI, backupHome: string, workspacesJsonPath: string) {
		const environmentService = new TestBackupEnvironmentService(workspaceBackupPath);
		const fileService = new FileService(new NullLogService());
		const diskFileSystemProvider = new DiskFileSystemProvider(new NullLogService());
		fileService.registerProvider(Schemas.file, diskFileSystemProvider);
		fileService.registerProvider(Schemas.userData, new FileUserDataProvider(environmentService.appSettingsHome, environmentService.backupHome, diskFileSystemProvider, environmentService));

		super(environmentService, fileService);

		this.fileService = fileService;
	}

	toBackupResource(resource: URI): URI {
		return super.toBackupResource(resource);
	}
}

suite('BackupFileService', () => {
	let service: TestBackupFileService;

	setup(async () => {
		service = new TestBackupFileService(workspaceResource, backupHome, workspacesJsonPath);

		// Delete any existing backups completely and then re-create it.
		await pfs.rimraf(backupHome, pfs.RimRafMode.MOVE);
		await pfs.mkdirp(backupHome);

		return pfs.writeFile(workspacesJsonPath, '');
	});

	teardown(() => {
		return pfs.rimraf(backupHome, pfs.RimRafMode.MOVE);
	});

	suite('hashPath', () => {
		test('should correctly hash the path for untitled scheme URIs', () => {
			const uri = URI.from({
				scheme: 'untitled',
				path: 'Untitled-1'
			});
			const actual = hashPath(uri);
			// If these hashes change people will lose their backed up files!
			assert.equal(actual, '13264068d108c6901b3592ea654fcd57');
			assert.equal(actual, crypto.createHash('md5').update(uri.fsPath).digest('hex'));
		});

		test('should correctly hash the path for file scheme URIs', () => {
			const uri = URI.file('/foo');
			const actual = hashPath(uri);
			// If these hashes change people will lose their backed up files!
			if (platform.isWindows) {
				assert.equal(actual, 'dec1a583f52468a020bd120c3f01d812');
			} else {
				assert.equal(actual, '1effb2475fcfba4f9e8b8a1dbc8f3caf');
			}
			assert.equal(actual, crypto.createHash('md5').update(uri.fsPath).digest('hex'));
		});
	});

	suite('getBackupResource', () => {
		test('should get the correct backup path for text files', () => {
			// Format should be: <backupHome>/<workspaceHash>/<scheme>/<filePathHash>
			const backupResource = fooFile;
			const workspaceHash = hashPath(workspaceResource);
			const filePathHash = hashPath(backupResource);
			const expectedPath = URI.file(path.join(appSettingsHome, BACKUPS, workspaceHash, Schemas.file, filePathHash)).with({ scheme: Schemas.userData }).toString();
			assert.equal(service.toBackupResource(backupResource).toString(), expectedPath);
		});

		test('should get the correct backup path for untitled files', () => {
			// Format should be: <backupHome>/<workspaceHash>/<scheme>/<filePath>
			const backupResource = URI.from({ scheme: Schemas.untitled, path: 'Untitled-1' });
			const workspaceHash = hashPath(workspaceResource);
			const filePathHash = hashPath(backupResource);
			const expectedPath = URI.file(path.join(appSettingsHome, BACKUPS, workspaceHash, Schemas.untitled, filePathHash)).with({ scheme: Schemas.userData }).toString();
			assert.equal(service.toBackupResource(backupResource).toString(), expectedPath);
		});
	});

	suite('loadBackupResource', () => {
		test('should return whether a backup resource exists', async () => {
			await pfs.mkdirp(path.dirname(fooBackupPath));
			fs.writeFileSync(fooBackupPath, 'foo');
			service = new TestBackupFileService(workspaceResource, backupHome, workspacesJsonPath);
			const resource = await service.loadBackupResource(fooFile);
			assert.ok(resource);
			assert.equal(path.basename(resource!.fsPath), path.basename(fooBackupPath));
			const hasBackups = await service.hasBackups();
			assert.ok(hasBackups);
		});
	});

	suite('backupResource', () => {
		test('text file', async () => {
			await service.backupResource(fooFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'file')).length, 1);
			assert.equal(fs.existsSync(fooBackupPath), true);
			assert.equal(fs.readFileSync(fooBackupPath), `${fooFile.toString()}\ntest`);
			assert.ok(service.hasBackupSync(fooFile));
		});

		test('text file (with version)', async () => {
			await service.backupResource(fooFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false), 666);
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'file')).length, 1);
			assert.equal(fs.existsSync(fooBackupPath), true);
			assert.equal(fs.readFileSync(fooBackupPath), `${fooFile.toString()}\ntest`);
			assert.ok(!service.hasBackupSync(fooFile, 555));
			assert.ok(service.hasBackupSync(fooFile, 666));
		});

		test('text file (with meta)', async () => {
			await service.backupResource(fooFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false), undefined, { etag: '678', orphaned: true });
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'file')).length, 1);
			assert.equal(fs.existsSync(fooBackupPath), true);
			assert.equal(fs.readFileSync(fooBackupPath).toString(), `${fooFile.toString()} {"etag":"678","orphaned":true}\ntest`);
			assert.ok(service.hasBackupSync(fooFile));
		});

		test('untitled file', async () => {
			await service.backupResource(untitledFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'untitled')).length, 1);
			assert.equal(fs.existsSync(untitledBackupPath), true);
			assert.equal(fs.readFileSync(untitledBackupPath), `${untitledFile.toString()}\ntest`);
			assert.ok(service.hasBackupSync(untitledFile));
		});

		test('text file (ITextSnapshot)', async () => {
			const model = TextModel.createFromString('test');

			await service.backupResource(fooFile, model.createSnapshot());
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'file')).length, 1);
			assert.equal(fs.existsSync(fooBackupPath), true);
			assert.equal(fs.readFileSync(fooBackupPath), `${fooFile.toString()}\ntest`);
			assert.ok(service.hasBackupSync(fooFile));

			model.dispose();
		});

		test('untitled file (ITextSnapshot)', async () => {
			const model = TextModel.createFromString('test');

			await service.backupResource(untitledFile, model.createSnapshot());
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'untitled')).length, 1);
			assert.equal(fs.existsSync(untitledBackupPath), true);
			assert.equal(fs.readFileSync(untitledBackupPath), `${untitledFile.toString()}\ntest`);

			model.dispose();
		});

		test('text file (large file, ITextSnapshot)', async () => {
			const largeString = (new Array(10 * 1024)).join('Large String\n');
			const model = TextModel.createFromString(largeString);

			await service.backupResource(fooFile, model.createSnapshot());
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'file')).length, 1);
			assert.equal(fs.existsSync(fooBackupPath), true);
			assert.equal(fs.readFileSync(fooBackupPath), `${fooFile.toString()}\n${largeString}`);
			assert.ok(service.hasBackupSync(fooFile));

			model.dispose();
		});

		test('untitled file (large file, ITextSnapshot)', async () => {
			const largeString = (new Array(10 * 1024)).join('Large String\n');
			const model = TextModel.createFromString(largeString);

			await service.backupResource(untitledFile, model.createSnapshot());
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'untitled')).length, 1);
			assert.equal(fs.existsSync(untitledBackupPath), true);
			assert.equal(fs.readFileSync(untitledBackupPath), `${untitledFile.toString()}\n${largeString}`);
			assert.ok(service.hasBackupSync(untitledFile));

			model.dispose();
		});
	});

	suite('discardResourceBackup', () => {
		test('text file', async () => {
			await service.backupResource(fooFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'file')).length, 1);
			assert.ok(service.hasBackupSync(fooFile));

			await service.discardResourceBackup(fooFile);
			assert.equal(fs.existsSync(fooBackupPath), false);
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'file')).length, 0);
			assert.ok(!service.hasBackupSync(fooFile));
		});

		test('untitled file', async () => {
			await service.backupResource(untitledFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'untitled')).length, 1);
			await service.discardResourceBackup(untitledFile);
			assert.equal(fs.existsSync(untitledBackupPath), false);
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'untitled')).length, 0);
		});
	});

	suite('discardAllWorkspaceBackups', () => {
		test('text file', async () => {
			await service.backupResource(fooFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'file')).length, 1);
			await service.backupResource(barFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'file')).length, 2);
			await service.discardAllWorkspaceBackups();
			assert.equal(fs.existsSync(fooBackupPath), false);
			assert.equal(fs.existsSync(barBackupPath), false);
			assert.equal(fs.existsSync(path.join(workspaceBackupPath, 'file')), false);
		});

		test('untitled file', async () => {
			await service.backupResource(untitledFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			assert.equal(fs.readdirSync(path.join(workspaceBackupPath, 'untitled')).length, 1);
			await service.discardAllWorkspaceBackups();
			assert.equal(fs.existsSync(untitledBackupPath), false);
			assert.equal(fs.existsSync(path.join(workspaceBackupPath, 'untitled')), false);
		});

		test('should disable further backups', async () => {
			await service.discardAllWorkspaceBackups();
			await service.backupResource(untitledFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			assert.equal(fs.existsSync(workspaceBackupPath), false);
		});
	});

	suite('getWorkspaceFileBackups', () => {
		test('("file") - text file', async () => {
			await service.backupResource(fooFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			const textFiles = await service.getWorkspaceFileBackups();
			assert.deepEqual(textFiles.map(f => f.fsPath), [fooFile.fsPath]);
			await service.backupResource(barFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			const textFiles_1 = await service.getWorkspaceFileBackups();
			assert.deepEqual(textFiles_1.map(f => f.fsPath), [fooFile.fsPath, barFile.fsPath]);
		});

		test('("file") - untitled file', async () => {
			await service.backupResource(untitledFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			const textFiles = await service.getWorkspaceFileBackups();
			assert.deepEqual(textFiles.map(f => f.fsPath), [untitledFile.fsPath]);
		});

		test('("untitled") - untitled file', async () => {
			await service.backupResource(untitledFile, createTextBufferFactory('test').create(DefaultEndOfLine.LF).createSnapshot(false));
			const textFiles = await service.getWorkspaceFileBackups();
			assert.deepEqual(textFiles.map(f => f.fsPath), ['Untitled-1']);
		});
	});

	suite('resolveBackupContent', () => {

		interface IBackupTestMetaData {
			mtime?: number;
			size?: number;
			etag?: string;
			orphaned?: boolean;
		}

		test('should restore the original contents (untitled file)', async () => {
			const contents = 'test\nand more stuff';

			await testResolveBackup(untitledFile, contents);
		});

		test('should restore the original contents (untitled file with metadata)', async () => {
			const contents = 'test\nand more stuff';

			const meta = {
				etag: 'the Etag',
				size: 666,
				mtime: Date.now(),
				orphaned: true
			};

			await testResolveBackup(untitledFile, contents, meta);
		});

		test('should restore the original contents (text file)', async () => {
			const contents = [
				'Lorem ipsum ',
				'dolor öäü sit amet ',
				'consectetur ',
				'adipiscing ßß elit'
			].join('');

			await testResolveBackup(fooFile, contents);
		});

		test('should restore the original contents (text file - custom scheme)', async () => {
			const contents = [
				'Lorem ipsum ',
				'dolor öäü sit amet ',
				'consectetur ',
				'adipiscing ßß elit'
			].join('');

			await testResolveBackup(customFile, contents);
		});

		test('should restore the original contents (text file with metadata)', async () => {
			const contents = [
				'Lorem ipsum ',
				'dolor öäü sit amet ',
				'adipiscing ßß elit',
				'consectetur '
			].join('');

			const meta = {
				etag: 'theEtag',
				size: 888,
				mtime: Date.now(),
				orphaned: false
			};

			await testResolveBackup(fooFile, contents, meta);
		});

		test('should restore the original contents (text file with metadata changed once)', async () => {
			const contents = [
				'Lorem ipsum ',
				'dolor öäü sit amet ',
				'adipiscing ßß elit',
				'consectetur '
			].join('');

			const meta = {
				etag: 'theEtag',
				size: 888,
				mtime: Date.now(),
				orphaned: false
			};

			await testResolveBackup(fooFile, contents, meta);

			// Change meta and test again
			meta.size = 999;
			await testResolveBackup(fooFile, contents, meta);
		});

		test('should restore the original contents (text file with broken metadata)', async () => {
			const contents = [
				'Lorem ipsum ',
				'dolor öäü sit amet ',
				'adipiscing ßß elit',
				'consectetur '
			].join('');

			const meta = {
				etag: 'theEtag',
				size: 888,
				mtime: Date.now(),
				orphaned: false
			};

			await service.backupResource(fooFile, createTextBufferFactory(contents).create(DefaultEndOfLine.LF).createSnapshot(false), 1, meta);

			assert.ok(await service.loadBackupResource(fooFile));

			const fileContents = fs.readFileSync(fooBackupPath).toString();
			assert.equal(fileContents.indexOf(fooFile.toString()), 0);

			const metaIndex = fileContents.indexOf('{');
			const newFileContents = fileContents.substring(0, metaIndex) + '{{' + fileContents.substr(metaIndex);
			fs.writeFileSync(fooBackupPath, newFileContents);

			const backup = await service.resolveBackupContent(service.toBackupResource(fooFile));
			assert.equal(contents, snapshotToString(backup.value.create(platform.isWindows ? DefaultEndOfLine.CRLF : DefaultEndOfLine.LF).createSnapshot(true)));
			assert.ok(!backup.meta);
		});

		test('should restore the original contents (text file with metadata and fragment URI)', async () => {
			const contents = [
				'Lorem ipsum ',
				'dolor öäü sit amet ',
				'adipiscing ßß elit',
				'consectetur '
			].join('');

			const meta = {
				etag: 'theEtag',
				size: 888,
				mtime: Date.now(),
				orphaned: false
			};

			await testResolveBackup(customFileWithFragment, contents, meta);
		});

		test('should restore the original contents (text file with space in name with metadata)', async () => {
			const contents = [
				'Lorem ipsum ',
				'dolor öäü sit amet ',
				'adipiscing ßß elit',
				'consectetur '
			].join('');

			const meta = {
				etag: 'theEtag',
				size: 888,
				mtime: Date.now(),
				orphaned: false
			};

			await testResolveBackup(fooBarFile, contents, meta);
		});

		test('should restore the original contents (text file with too large metadata to persist)', async () => {
			const contents = [
				'Lorem ipsum ',
				'dolor öäü sit amet ',
				'adipiscing ßß elit',
				'consectetur '
			].join('');

			const meta = {
				etag: (new Array(100 * 1024)).join('Large String'),
				size: 888,
				mtime: Date.now(),
				orphaned: false
			};

			await testResolveBackup(fooBarFile, contents, meta, null);
		});

		test('should throw an error when restoring invalid backup', async () => {
			const contents = 'test\nand more stuff';

			await service.backupResource(fooBarFile, createTextBufferFactory(contents).create(DefaultEndOfLine.LF).createSnapshot(false), 1);

			const backup = await service.loadBackupResource(fooBarFile);
			if (!backup) {
				throw new Error('Unexpected missing backup');
			}

			await service.fileService.writeFile(backup, VSBuffer.fromString(''));

			let err: Error;
			try {
				await service.resolveBackupContent<IBackupTestMetaData>(backup);
			} catch (error) {
				err = error;
			}

			assert.ok(err!);
		});

		async function testResolveBackup(resource: URI, contents: string, meta?: IBackupTestMetaData, expectedMeta?: IBackupTestMetaData | null) {
			if (typeof expectedMeta === 'undefined') {
				expectedMeta = meta;
			}

			await service.backupResource(resource, createTextBufferFactory(contents).create(DefaultEndOfLine.LF).createSnapshot(false), 1, meta);

			assert.ok(await service.loadBackupResource(resource));

			const backup = await service.resolveBackupContent<IBackupTestMetaData>(service.toBackupResource(resource));
			assert.equal(contents, snapshotToString(backup.value.create(platform.isWindows ? DefaultEndOfLine.CRLF : DefaultEndOfLine.LF).createSnapshot(true)));

			if (expectedMeta) {
				assert.equal(backup.meta!.etag, expectedMeta.etag);
				assert.equal(backup.meta!.size, expectedMeta.size);
				assert.equal(backup.meta!.mtime, expectedMeta.mtime);
				assert.equal(backup.meta!.orphaned, expectedMeta.orphaned);
			} else {
				assert.ok(!backup.meta);
			}
		}
	});
});

suite('BackupFilesModel', () => {

	let service: TestBackupFileService;

	setup(async () => {
		service = new TestBackupFileService(workspaceResource, backupHome, workspacesJsonPath);

		// Delete any existing backups completely and then re-create it.
		await pfs.rimraf(backupHome, pfs.RimRafMode.MOVE);
		await pfs.mkdirp(backupHome);

		return pfs.writeFile(workspacesJsonPath, '');
	});

	teardown(() => {
		return pfs.rimraf(backupHome, pfs.RimRafMode.MOVE);
	});

	test('simple', () => {
		const model = new BackupFilesModel(service.fileService);

		const resource1 = URI.file('test.html');

		assert.equal(model.has(resource1), false);

		model.add(resource1);

		assert.equal(model.has(resource1), true);
		assert.equal(model.has(resource1, 0), true);
		assert.equal(model.has(resource1, 1), false);
		assert.equal(model.has(resource1, 1, { foo: 'bar' }), false);

		model.remove(resource1);

		assert.equal(model.has(resource1), false);

		model.add(resource1);

		assert.equal(model.has(resource1), true);
		assert.equal(model.has(resource1, 0), true);
		assert.equal(model.has(resource1, 1), false);

		model.clear();

		assert.equal(model.has(resource1), false);

		model.add(resource1, 1);

		assert.equal(model.has(resource1), true);
		assert.equal(model.has(resource1, 0), false);
		assert.equal(model.has(resource1, 1), true);

		const resource2 = URI.file('test1.html');
		const resource3 = URI.file('test2.html');
		const resource4 = URI.file('test3.html');

		model.add(resource2);
		model.add(resource3);
		model.add(resource4, undefined, { foo: 'bar' });

		assert.equal(model.has(resource1), true);
		assert.equal(model.has(resource2), true);
		assert.equal(model.has(resource3), true);

		assert.equal(model.has(resource4), true);
		assert.equal(model.has(resource4, undefined, { foo: 'bar' }), true);
		assert.equal(model.has(resource4, undefined, { bar: 'foo' }), false);
	});

	test('resolve', async () => {
		await pfs.mkdirp(path.dirname(fooBackupPath));
		fs.writeFileSync(fooBackupPath, 'foo');
		const model = new BackupFilesModel(service.fileService);

		const resolvedModel = await model.resolve(URI.file(workspaceBackupPath));
		assert.equal(resolvedModel.has(URI.file(fooBackupPath)), true);
	});

	test('get', () => {
		const model = new BackupFilesModel(service.fileService);

		assert.deepEqual(model.get(), []);

		const file1 = URI.file('/root/file/foo.html');
		const file2 = URI.file('/root/file/bar.html');
		const untitled = URI.file('/root/untitled/bar.html');

		model.add(file1);
		model.add(file2);
		model.add(untitled);

		assert.deepEqual(model.get().map(f => f.fsPath), [file1.fsPath, file2.fsPath, untitled.fsPath]);
	});
});