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

import { createDecorator } from 'vs/platform/instantiation/common/instantiation';
import { localize } from 'vs/nls';
import { IWorkspaceFolder, IWorkspace, WorkspaceFolder } from 'vs/platform/workspace/common/workspace';
import { URI, UriComponents } from 'vs/base/common/uri';
import { isWindows, isLinux, isMacintosh } from 'vs/base/common/platform';
import { extname, isAbsolute } from 'vs/base/common/path';
import { extname as resourceExtname, extUriBiasedIgnorePathCase, IExtUri } from 'vs/base/common/resources';
import * as jsonEdit from 'vs/base/common/jsonEdit';
import * as json from 'vs/base/common/json';
import { Schemas } from 'vs/base/common/network';
import { normalizeDriveLetter } from 'vs/base/common/labels';
import { toSlashes } from 'vs/base/common/extpath';
import { FormattingOptions } from 'vs/base/common/jsonFormatter';
import { getRemoteAuthority } from 'vs/platform/remote/common/remoteHosts';
import { ILogService } from 'vs/platform/log/common/log';
import { Event } from 'vs/base/common/event';
import { IEnvironmentService } from 'vs/platform/environment/common/environment';

export const WORKSPACE_EXTENSION = 'code-workspace';
const WORKSPACE_SUFFIX = `.${WORKSPACE_EXTENSION}`;
export const WORKSPACE_FILTER = [{ name: localize('codeWorkspace', "Code Workspace"), extensions: [WORKSPACE_EXTENSION] }];
export const UNTITLED_WORKSPACE_NAME = 'workspace.json';

export function hasWorkspaceFileExtension(path: string | URI) {
	const ext = (typeof path === 'string') ? extname(path) : resourceExtname(path);

	return ext === WORKSPACE_SUFFIX;
}

export const IWorkspacesService = createDecorator<IWorkspacesService>('workspacesService');

export interface IWorkspacesService {

	readonly _serviceBrand: undefined;

	// Workspaces Management
	enterWorkspace(path: URI): Promise<IEnterWorkspaceResult | null>;
	createUntitledWorkspace(folders?: IWorkspaceFolderCreationData[], remoteAuthority?: string): Promise<IWorkspaceIdentifier>;
	deleteUntitledWorkspace(workspace: IWorkspaceIdentifier): Promise<void>;
	getWorkspaceIdentifier(workspacePath: URI): Promise<IWorkspaceIdentifier>;

	// Workspaces History
	readonly onDidChangeRecentlyOpened: Event<void>;
	addRecentlyOpened(recents: IRecent[]): Promise<void>;
	removeRecentlyOpened(workspaces: URI[]): Promise<void>;
	clearRecentlyOpened(): Promise<void>;
	getRecentlyOpened(): Promise<IRecentlyOpened>;

	// Dirty Workspaces
	getDirtyWorkspaces(): Promise<Array<IWorkspaceIdentifier | URI>>;
}

//#region Workspaces Recently Opened

export interface IRecentlyOpened {
	workspaces: Array<IRecentWorkspace | IRecentFolder>;
	files: IRecentFile[];
}

export type IRecent = IRecentWorkspace | IRecentFolder | IRecentFile;

export interface IRecentWorkspace {
	workspace: IWorkspaceIdentifier;
	label?: string;
}

export interface IRecentFolder {
	folderUri: URI;
	label?: string;
}

export interface IRecentFile {
	fileUri: URI;
	label?: string;
}

export function isRecentWorkspace(curr: IRecent): curr is IRecentWorkspace {
	return curr.hasOwnProperty('workspace');
}

export function isRecentFolder(curr: IRecent): curr is IRecentFolder {
	return curr.hasOwnProperty('folderUri');
}

export function isRecentFile(curr: IRecent): curr is IRecentFile {
	return curr.hasOwnProperty('fileUri');
}

//#endregion

//#region Identifiers / Payload

export interface IBaseWorkspaceIdentifier {

	/**
	 * Every workspace (multi-root, single folder or empty)
	 * has a unique identifier. It is not possible to open
	 * a workspace with the same `id` in multiple windows
	 */
	id: string;
}

/**
 * A single folder workspace identifier is a path to a folder + id.
 */
export interface ISingleFolderWorkspaceIdentifier extends IBaseWorkspaceIdentifier {

	/**
	 * Folder path as `URI`.
	 */
	uri: URI;
}

export interface ISerializedSingleFolderWorkspaceIdentifier extends IBaseWorkspaceIdentifier {
	uri: UriComponents;
}

export function isSingleFolderWorkspaceIdentifier(obj: unknown): obj is ISingleFolderWorkspaceIdentifier {
	const singleFolderIdentifier = obj as ISingleFolderWorkspaceIdentifier | undefined;

	return typeof singleFolderIdentifier?.id === 'string' && URI.isUri(singleFolderIdentifier.uri);
}

/**
 * A multi-root workspace identifier is a path to a workspace file + id.
 */
export interface IWorkspaceIdentifier extends IBaseWorkspaceIdentifier {

	/**
	 * Workspace config file path as `URI`.
	 */
	configPath: URI;
}

export interface ISerializedWorkspaceIdentifier extends IBaseWorkspaceIdentifier {
	configPath: UriComponents;
}

export function toWorkspaceIdentifier(workspace: IWorkspace): IWorkspaceIdentifier | ISingleFolderWorkspaceIdentifier | undefined {

	// Multi root
	if (workspace.configuration) {
		return {
			id: workspace.id,
			configPath: workspace.configuration
		};
	}

	// Single folder
	if (workspace.folders.length === 1) {
		return {
			id: workspace.id,
			uri: workspace.folders[0].uri
		};
	}

	// Empty workspace
	return undefined;
}

export function isWorkspaceIdentifier(obj: unknown): obj is IWorkspaceIdentifier {
	const workspaceIdentifier = obj as IWorkspaceIdentifier | undefined;

	return typeof workspaceIdentifier?.id === 'string' && URI.isUri(workspaceIdentifier.configPath);
}

export function reviveIdentifier(identifier: undefined): undefined;
export function reviveIdentifier(identifier: ISerializedWorkspaceIdentifier): IWorkspaceIdentifier;
export function reviveIdentifier(identifier: ISerializedSingleFolderWorkspaceIdentifier): ISingleFolderWorkspaceIdentifier;
export function reviveIdentifier(identifier: IEmptyWorkspaceIdentifier): IEmptyWorkspaceIdentifier;
export function reviveIdentifier(identifier: ISerializedWorkspaceIdentifier | ISerializedSingleFolderWorkspaceIdentifier | IEmptyWorkspaceIdentifier | undefined): IWorkspaceIdentifier | ISingleFolderWorkspaceIdentifier | IEmptyWorkspaceIdentifier | undefined;
export function reviveIdentifier(identifier: ISerializedWorkspaceIdentifier | ISerializedSingleFolderWorkspaceIdentifier | IEmptyWorkspaceIdentifier | undefined): IWorkspaceIdentifier | ISingleFolderWorkspaceIdentifier | IEmptyWorkspaceIdentifier | undefined {

	// Single Folder
	const singleFolderIdentifierCandidate = identifier as ISerializedSingleFolderWorkspaceIdentifier | undefined;
	if (singleFolderIdentifierCandidate?.uri) {
		return { id: singleFolderIdentifierCandidate.id, uri: URI.revive(singleFolderIdentifierCandidate.uri) };
	}

	// Multi folder
	const workspaceIdentifierCandidate = identifier as ISerializedWorkspaceIdentifier | undefined;
	if (workspaceIdentifierCandidate?.configPath) {
		return { id: workspaceIdentifierCandidate.id, configPath: URI.revive(workspaceIdentifierCandidate.configPath) };
	}

	// Empty
	if (identifier?.id) {
		return { id: identifier.id };
	}

	return undefined;
}

export function isUntitledWorkspace(path: URI, environmentService: IEnvironmentService): boolean {
	return extUriBiasedIgnorePathCase.isEqualOrParent(path, environmentService.untitledWorkspacesHome);
}

export interface IEmptyWorkspaceIdentifier extends IBaseWorkspaceIdentifier { }

export type IWorkspaceInitializationPayload = IWorkspaceIdentifier | ISingleFolderWorkspaceIdentifier | IEmptyWorkspaceIdentifier;

//#endregion

//#region Workspace File Utilities

export function isStoredWorkspaceFolder(obj: unknown): obj is IStoredWorkspaceFolder {
	return isRawFileWorkspaceFolder(obj) || isRawUriWorkspaceFolder(obj);
}

export function isRawFileWorkspaceFolder(obj: unknown): obj is IRawFileWorkspaceFolder {
	const candidate = obj as IRawFileWorkspaceFolder | undefined;

	return typeof candidate?.path === 'string' && (!candidate.name || typeof candidate.name === 'string');
}

export function isRawUriWorkspaceFolder(obj: unknown): obj is IRawUriWorkspaceFolder {
	const candidate = obj as IRawUriWorkspaceFolder | undefined;

	return typeof candidate?.uri === 'string' && (!candidate.name || typeof candidate.name === 'string');
}

export interface IRawFileWorkspaceFolder {
	path: string;
	name?: string;
}

export interface IRawUriWorkspaceFolder {
	uri: string;
	name?: string;
}

export type IStoredWorkspaceFolder = IRawFileWorkspaceFolder | IRawUriWorkspaceFolder;

export interface IResolvedWorkspace extends IWorkspaceIdentifier {
	folders: IWorkspaceFolder[];
	remoteAuthority?: string;
}

export interface IStoredWorkspace {
	folders: IStoredWorkspaceFolder[];
	remoteAuthority?: string;
}

export interface IWorkspaceFolderCreationData {
	uri: URI;
	name?: string;
}

export interface IUntitledWorkspaceInfo {
	workspace: IWorkspaceIdentifier;
	remoteAuthority?: string;
}

export interface IEnterWorkspaceResult {
	workspace: IWorkspaceIdentifier;
	backupPath?: string;
}

/**
 * Given a folder URI and the workspace config folder, computes the IStoredWorkspaceFolder using
* a relative or absolute path or a uri.
 * Undefined is returned if the folderURI and the targetConfigFolderURI don't have the same schema or authority
 *
 * @param folderURI a workspace folder
 * @param forceAbsolute if set, keep the path absolute
 * @param folderName a workspace name
 * @param targetConfigFolderURI the folder where the workspace is living in
 * @param useSlashForPath if set, use forward slashes for file paths on windows
 */
export function getStoredWorkspaceFolder(folderURI: URI, forceAbsolute: boolean, folderName: string | undefined, targetConfigFolderURI: URI, useSlashForPath = !isWindows, extUri: IExtUri): IStoredWorkspaceFolder {
	if (folderURI.scheme !== targetConfigFolderURI.scheme) {
		return { name: folderName, uri: folderURI.toString(true) };
	}

	let folderPath = !forceAbsolute ? extUri.relativePath(targetConfigFolderURI, folderURI) : undefined;
	if (folderPath !== undefined) {
		if (folderPath.length === 0) {
			folderPath = '.';
		} else if (isWindows && folderURI.scheme === Schemas.file && !useSlashForPath) {
			// Windows gets special treatment:
			// - use backslahes unless slash is used by other existing folders
			folderPath = folderPath.replace(/\//g, '\\');
		}
	} else {

		// use absolute path
		if (folderURI.scheme === Schemas.file) {
			folderPath = folderURI.fsPath;
			if (isWindows) {
				// Windows gets special treatment:
				// - normalize all paths to get nice casing of drive letters
				// - use backslahes unless slash is used by other existing folders
				folderPath = normalizeDriveLetter(folderPath);
				if (useSlashForPath) {
					folderPath = toSlashes(folderPath);
				}
			}
		} else {
			if (!extUri.isEqualAuthority(folderURI.authority, targetConfigFolderURI.authority)) {
				return { name: folderName, uri: folderURI.toString(true) };
			}
			folderPath = folderURI.path;
		}
	}

	return { name: folderName, path: folderPath };
}

export function toWorkspaceFolders(configuredFolders: IStoredWorkspaceFolder[], workspaceConfigFile: URI, extUri: IExtUri): WorkspaceFolder[] {
	let result: WorkspaceFolder[] = [];
	let seen: Set<string> = new Set();

	const relativeTo = extUri.dirname(workspaceConfigFile);
	for (let configuredFolder of configuredFolders) {
		let uri: URI | null = null;
		if (isRawFileWorkspaceFolder(configuredFolder)) {
			if (configuredFolder.path) {
				uri = extUri.resolvePath(relativeTo, configuredFolder.path);
			}
		} else if (isRawUriWorkspaceFolder(configuredFolder)) {
			try {
				uri = URI.parse(configuredFolder.uri);
				// this makes sure all workspace folder are absolute
				if (uri.path[0] !== '/') {
					uri = uri.with({ path: '/' + uri.path });
				}
			} catch (e) {
				console.warn(e);
				// ignore
			}
		}
		if (uri) {
			// remove duplicates
			let comparisonKey = extUri.getComparisonKey(uri);
			if (!seen.has(comparisonKey)) {
				seen.add(comparisonKey);

				const name = configuredFolder.name || extUri.basenameOrAuthority(uri);
				result.push(new WorkspaceFolder({ uri, name, index: result.length }, configuredFolder));
			}
		}
	}

	return result;
}

/**
 * Rewrites the content of a workspace file to be saved at a new location.
 * Throws an exception if file is not a valid workspace file
 */
export function rewriteWorkspaceFileForNewLocation(rawWorkspaceContents: string, configPathURI: URI, isFromUntitledWorkspace: boolean, targetConfigPathURI: URI, extUri: IExtUri) {
	let storedWorkspace = doParseStoredWorkspace(configPathURI, rawWorkspaceContents);

	const sourceConfigFolder = extUri.dirname(configPathURI);
	const targetConfigFolder = extUri.dirname(targetConfigPathURI);

	const rewrittenFolders: IStoredWorkspaceFolder[] = [];
	const slashForPath = useSlashForPath(storedWorkspace.folders);

	for (const folder of storedWorkspace.folders) {
		const folderURI = isRawFileWorkspaceFolder(folder) ? extUri.resolvePath(sourceConfigFolder, folder.path) : URI.parse(folder.uri);
		let absolute;
		if (isFromUntitledWorkspace) {
			// if it was an untitled workspace, try to make paths relative
			absolute = false;
		} else {
			// for existing workspaces, preserve whether a path was absolute or relative
			absolute = !isRawFileWorkspaceFolder(folder) || isAbsolute(folder.path);
		}
		rewrittenFolders.push(getStoredWorkspaceFolder(folderURI, absolute, folder.name, targetConfigFolder, slashForPath, extUri));
	}

	// Preserve as much of the existing workspace as possible by using jsonEdit
	// and only changing the folders portion.
	const formattingOptions: FormattingOptions = { insertSpaces: false, tabSize: 4, eol: (isLinux || isMacintosh) ? '\n' : '\r\n' };
	const edits = jsonEdit.setProperty(rawWorkspaceContents, ['folders'], rewrittenFolders, formattingOptions);
	let newContent = jsonEdit.applyEdits(rawWorkspaceContents, edits);

	if (storedWorkspace.remoteAuthority === getRemoteAuthority(targetConfigPathURI)) {
		// unsaved remote workspaces have the remoteAuthority set. Remove it when no longer nexessary.
		newContent = jsonEdit.applyEdits(newContent, jsonEdit.removeProperty(newContent, ['remoteAuthority'], formattingOptions));
	}

	return newContent;
}

function doParseStoredWorkspace(path: URI, contents: string): IStoredWorkspace {

	// Parse workspace file
	let storedWorkspace: IStoredWorkspace = json.parse(contents); // use fault tolerant parser

	// Filter out folders which do not have a path or uri set
	if (storedWorkspace && Array.isArray(storedWorkspace.folders)) {
		storedWorkspace.folders = storedWorkspace.folders.filter(folder => isStoredWorkspaceFolder(folder));
	} else {
		throw new Error(`${path} looks like an invalid workspace file.`);
	}

	return storedWorkspace;
}

export function useSlashForPath(storedFolders: IStoredWorkspaceFolder[]): boolean {
	if (isWindows) {
		return storedFolders.some(folder => isRawFileWorkspaceFolder(folder) && folder.path.indexOf('/') >= 0);
	}

	return true;
}

//#endregion

//#region Workspace Storage

interface ISerializedRecentlyOpened {
	workspaces3: Array<ISerializedWorkspace | string>; // workspace or URI.toString() // added in 1.32
	workspaceLabels?: Array<string | null>; // added in 1.33
	files2: string[]; // files as URI.toString() // added in 1.32
	fileLabels?: Array<string | null>; // added in 1.33
}

interface ISerializedWorkspace { id: string; configURIPath: string; }

export type RecentlyOpenedStorageData = object;

export function restoreRecentlyOpened(data: RecentlyOpenedStorageData | undefined, logService: ILogService): IRecentlyOpened {
	const result: IRecentlyOpened = { workspaces: [], files: [] };
	if (data) {
		const restoreGracefully = function <T>(entries: T[], func: (entry: T, index: number) => void) {
			for (let i = 0; i < entries.length; i++) {
				try {
					func(entries[i], i);
				} catch (e) {
					logService.warn(`Error restoring recent entry ${JSON.stringify(entries[i])}: ${e.toString()}. Skip entry.`);
				}
			}
		};

		const storedRecents = data as ISerializedRecentlyOpened;
		if (Array.isArray(storedRecents.workspaces3)) {
			restoreGracefully(storedRecents.workspaces3, (workspace, i) => {
				const label: string | undefined = (Array.isArray(storedRecents.workspaceLabels) && storedRecents.workspaceLabels[i]) || undefined;
				if (typeof workspace === 'object' && typeof workspace.id === 'string' && typeof workspace.configURIPath === 'string') {
					result.workspaces.push({ label, workspace: { id: workspace.id, configPath: URI.parse(workspace.configURIPath) } });
				} else if (typeof workspace === 'string') {
					result.workspaces.push({ label, folderUri: URI.parse(workspace) });
				}
			});
		}
		if (Array.isArray(storedRecents.files2)) {
			restoreGracefully(storedRecents.files2, (file, i) => {
				const label: string | undefined = (Array.isArray(storedRecents.fileLabels) && storedRecents.fileLabels[i]) || undefined;
				if (typeof file === 'string') {
					result.files.push({ label, fileUri: URI.parse(file) });
				}
			});
		}
	}

	return result;
}

export function toStoreData(recents: IRecentlyOpened): RecentlyOpenedStorageData {
	const serialized: ISerializedRecentlyOpened = { workspaces3: [], files2: [] };

	let hasLabel = false;
	const workspaceLabels: (string | null)[] = [];
	for (const recent of recents.workspaces) {
		if (isRecentFolder(recent)) {
			serialized.workspaces3.push(recent.folderUri.toString());
		} else {
			serialized.workspaces3.push({ id: recent.workspace.id, configURIPath: recent.workspace.configPath.toString() });
		}
		workspaceLabels.push(recent.label || null);
		hasLabel = hasLabel || !!recent.label;
	}

	if (hasLabel) {
		serialized.workspaceLabels = workspaceLabels;
	}

	hasLabel = false;

	const fileLabels: (string | null)[] = [];
	for (const recent of recents.files) {
		serialized.files2.push(recent.fileUri.toString());
		fileLabels.push(recent.label || null);
		hasLabel = hasLabel || !!recent.label;
	}

	if (hasLabel) {
		serialized.fileLabels = fileLabels;
	}

	return serialized;
}

//#endregion
