/// <reference types="node"/>
import {ChildProcess} from 'child_process';
import {Stream, Readable as ReadableStream} from 'stream';

declare namespace execa {
	type StdioOption =
		| 'pipe'
		| 'ipc'
		| 'ignore'
		| 'inherit'
		| Stream
		| number
		| undefined;

	interface CommonOptions<EncodingType> {
		/**
		Kill the spawned process when the parent process exits unless either:
			- the spawned process is [`detached`](https://nodejs.org/api/child_process.html#child_process_options_detached)
			- the parent process is terminated abruptly, for example, with `SIGKILL` as opposed to `SIGTERM` or a normal exit

		@default true
		*/
		readonly cleanup?: boolean;

		/**
		Prefer locally installed binaries when looking for a binary to execute.

		If you `$ npm install foo`, you can then `execa('foo')`.

		@default false
		*/
		readonly preferLocal?: boolean;

		/**
		Preferred path to find locally installed binaries in (use with `preferLocal`).

		@default process.cwd()
		*/
		readonly localDir?: string;

		/**
		Buffer the output from the spawned process. When buffering is disabled you must consume the output of the `stdout` and `stderr` streams because the promise will not be resolved/rejected until they have completed.

		If the spawned process fails, `error.stdout`, `error.stderr`, and `error.all` will contain the buffered data.

		@default true
		*/
		readonly buffer?: boolean;

		/**
		Same options as [`stdio`](https://nodejs.org/dist/latest-v6.x/docs/api/child_process.html#child_process_options_stdio).

		@default 'pipe'
		*/
		readonly stdin?: StdioOption;

		/**
		Same options as [`stdio`](https://nodejs.org/dist/latest-v6.x/docs/api/child_process.html#child_process_options_stdio).

		@default 'pipe'
		*/
		readonly stdout?: StdioOption;

		/**
		Same options as [`stdio`](https://nodejs.org/dist/latest-v6.x/docs/api/child_process.html#child_process_options_stdio).

		@default 'pipe'
		*/
		readonly stderr?: StdioOption;

		/**
		Setting this to `false` resolves the promise with the error instead of rejecting it.

		@default true
		*/
		readonly reject?: boolean;

		/**
		Strip the final [newline character](https://en.wikipedia.org/wiki/Newline) from the output.

		@default true
		*/
		readonly stripFinalNewline?: boolean;

		/**
		Set to `false` if you don't want to extend the environment variables when providing the `env` property.

		@default true
		*/
		readonly extendEnv?: boolean;

		/**
		Current working directory of the child process.

		@default process.cwd()
		*/
		readonly cwd?: string;

		/**
		Environment key-value pairs. Extends automatically from `process.env`. Set `extendEnv` to `false` if you don't want this.

		@default process.env
		*/
		readonly env?: NodeJS.ProcessEnv;

		/**
		Explicitly set the value of `argv[0]` sent to the child process. This will be set to `command` or `file` if not specified.
		*/
		readonly argv0?: string;

		/**
		Child's [stdio](https://nodejs.org/api/child_process.html#child_process_options_stdio) configuration.

		@default 'pipe'
		*/
		readonly stdio?: 'pipe' | 'ignore' | 'inherit' | readonly StdioOption[];

		/**
		Prepare child to run independently of its parent process. Specific behavior [depends on the platform](https://nodejs.org/api/child_process.html#child_process_options_detached).

		@default false
		*/
		readonly detached?: boolean;

		/**
		Sets the user identity of the process.
		*/
		readonly uid?: number;

		/**
		Sets the group identity of the process.
		*/
		readonly gid?: number;

		/**
		If `true`, runs `command` inside of a shell. Uses `/bin/sh` on UNIX and `cmd.exe` on Windows. A different shell can be specified as a string. The shell should understand the `-c` switch on UNIX or `/d /s /c` on Windows.

		We recommend against using this option since it is:
		- not cross-platform, encouraging shell-specific syntax.
		- slower, because of the additional shell interpretation.
		- unsafe, potentially allowing command injection.

		@default false
		*/
		readonly shell?: boolean | string;

		/**
		Specify the character encoding used to decode the `stdout` and `stderr` output. If set to `null`, then `stdout` and `stderr` will be a `Buffer` instead of a string.

		@default 'utf8'
		*/
		readonly encoding?: EncodingType;

		/**
		If `timeout` is greater than `0`, the parent will send the signal identified by the `killSignal` property (the default is `SIGTERM`) if the child runs longer than `timeout` milliseconds.

		@default 0
		*/
		readonly timeout?: number;

		/**
		Largest amount of data in bytes allowed on `stdout` or `stderr`. Default: 100 MB.

		@default 100_000_000
		*/
		readonly maxBuffer?: number;

		/**
		Signal value to be used when the spawned process will be killed.

		@default 'SIGTERM'
		*/
		readonly killSignal?: string | number;

		/**
		If `true`, no quoting or escaping of arguments is done on Windows. Ignored on other platforms. This is set to `true` automatically when the `shell` option is `true`.

		@default false
		*/
		readonly windowsVerbatimArguments?: boolean;
	}

	interface Options<EncodingType = string> extends CommonOptions<EncodingType> {
		/**
		Write some input to the `stdin` of your binary.
		*/
		readonly input?: string | Buffer | ReadableStream;
	}

	interface SyncOptions<EncodingType = string> extends CommonOptions<EncodingType> {
		/**
		Write some input to the `stdin` of your binary.
		*/
		readonly input?: string | Buffer;
	}

	interface NodeOptions<EncodingType = string> extends Options<EncodingType> {
		/**
		The Node.js executable to use.

		@default process.execPath
		*/
		readonly nodePath?: string;

		/**
		List of [CLI options](https://nodejs.org/api/cli.html#cli_options) passed to the Node.js executable.

		@default process.execArgv
		*/
		readonly nodeOptions?: string[];
	}

	interface ExecaReturnBase<StdoutStderrType> {
		/**
		The file and arguments that were run.
		*/
		command: string;

		/**
		The numeric exit code of the process that was run.
		*/
		exitCode: number;

		/**
		The textual exit code of the process that was run.
		*/
		exitCodeName: string;

		/**
		The output of the process on stdout.
		*/
		stdout: StdoutStderrType;

		/**
		The output of the process on stderr.
		*/
		stderr: StdoutStderrType;

		/**
		Whether the process failed to run.
		*/
		failed: boolean;

		/**
		Whether the process timed out.
		*/
		timedOut: boolean;

		/**
		Whether the process was killed.
		*/
		killed: boolean;

		/**
		The signal that was used to terminate the process.
		*/
		signal?: string;
	}

	interface ExecaSyncReturnValue<StdoutErrorType = string>
		extends ExecaReturnBase<StdoutErrorType> {
	}

	/**
	Result of a child process execution. On success this is a plain object. On failure this is also an `Error` instance.

	The child process fails when:
	- its exit code is not `0`
	- it was killed with a signal
	- timing out
	- being canceled
	- there's not enough memory or there are already too many child processes
	*/
	interface ExecaReturnValue<StdoutErrorType = string>
		extends ExecaSyncReturnValue<StdoutErrorType> {
		/**
		The output of the process with `stdout` and `stderr` interleaved.
		*/
		all: StdoutErrorType;

		/**
		Whether the process was canceled.
		*/
		isCanceled: boolean;
	}

	interface ExecaSyncError<StdoutErrorType = string>
		extends Error,
			ExecaReturnBase<StdoutErrorType> {
		/**
		The error message.
		*/
		message: string;

		/**
		Original error message. This is `undefined` unless the child process exited due to an `error` event or a timeout.

		The `message` property contains both the `originalMessage` and some additional information added by Execa.
		*/
		originalMessage?: string;
	}

	interface ExecaError<StdoutErrorType = string>
		extends ExecaSyncError<StdoutErrorType> {
		/**
		The output of the process with `stdout` and `stderr` interleaved.
		*/
		all: StdoutErrorType;

		/**
		Whether the process was canceled.
		*/
		isCanceled: boolean;
	}

	interface KillOptions {
		/**
		Milliseconds to wait for the child process to terminate before sending `SIGKILL`.

		Can be disabled with `false`.

		@default 5000
		*/
		forceKillAfterTimeout?: number | false;
	}

	interface ExecaChildPromise<StdoutErrorType> {
		catch<ResultType = never>(
			onRejected?: (reason: ExecaError<StdoutErrorType>) => ResultType | PromiseLike<ResultType>
		): Promise<ExecaReturnValue<StdoutErrorType> | ResultType>;

		/**
		Same as the original [`child_process#kill()`](https://nodejs.org/api/child_process.html#child_process_subprocess_kill_signal), except if `signal` is `SIGTERM` (the default value) and the child process is not terminated after 5 seconds, force it by sending `SIGKILL`.
		*/
		kill(signal?: string, options?: execa.KillOptions): void;

		/**
		Similar to [`childProcess.kill()`](https://nodejs.org/api/child_process.html#child_process_subprocess_kill_signal). This is preferred when cancelling the child process execution as the error is more descriptive and [`childProcessResult.isCanceled`](#iscanceled) is set to `true`.
		*/
		cancel(): void;

		/**
		Stream combining/interleaving [`stdout`](https://nodejs.org/api/child_process.html#child_process_subprocess_stdout) and [`stderr`](https://nodejs.org/api/child_process.html#child_process_subprocess_stderr).

		This is `undefined` when both `stdout` and `stderr` options are set to [`'pipe'`, `'ipc'`, `Stream` or `integer`](https://nodejs.org/dist/latest-v6.x/docs/api/child_process.html#child_process_options_stdio).
		*/
		all?: ReadableStream;
	}

	type ExecaChildProcess<StdoutErrorType = string> = ChildProcess &
		ExecaChildPromise<StdoutErrorType> &
		Promise<ExecaReturnValue<StdoutErrorType>>;
}

declare const execa: {
	/**
	Execute a file.

	Think of this as a mix of `child_process.execFile` and `child_process.spawn`.

	@param file - The program/script to execute.
	@param arguments - Arguments to pass to `file` on execution.
	@returns A [`child_process` instance](https://nodejs.org/api/child_process.html#child_process_class_childprocess), which is enhanced to also be a `Promise` for a result `Object` with `stdout` and `stderr` properties.

	@example
	```
	import execa from 'execa';

	(async () => {
		const {stdout} = await execa('echo', ['unicorns']);
		console.log(stdout);
		//=> 'unicorns'

		// Cancelling a spawned process
		const subprocess = execa('node');
		setTimeout(() => { spawned.cancel() }, 1000);
		try {
			await subprocess;
		} catch (error) {
			console.log(subprocess.killed); // true
			console.log(error.isCanceled); // true
		}
	})();

	// Pipe the child process stdout to the current stdout
	execa('echo', ['unicorns']).stdout.pipe(process.stdout);
	```
	*/
	(
		file: string,
		arguments?: readonly string[],
		options?: execa.Options
	): execa.ExecaChildProcess;
	(
		file: string,
		arguments?: readonly string[],
		options?: execa.Options<null>
	): execa.ExecaChildProcess<Buffer>;
	(file: string, options?: execa.Options): execa.ExecaChildProcess;
	(file: string, options?: execa.Options<null>): execa.ExecaChildProcess<
		Buffer
	>;

	/**
	Execute a file synchronously.

	This method throws an `Error` if the command fails.

	@param file - The program/script to execute.
	@param arguments - Arguments to pass to `file` on execution.
	@returns A result `Object` with `stdout` and `stderr` properties.
	*/
	sync(
		file: string,
		arguments?: readonly string[],
		options?: execa.SyncOptions
	): execa.ExecaSyncReturnValue;
	sync(
		file: string,
		arguments?: readonly string[],
		options?: execa.SyncOptions<null>
	): execa.ExecaSyncReturnValue<Buffer>;
	sync(file: string, options?: execa.SyncOptions): execa.ExecaSyncReturnValue;
	sync(
		file: string,
		options?: execa.SyncOptions<null>
	): execa.ExecaSyncReturnValue<Buffer>;

	/**
	Same as `execa()` except both file and arguments are specified in a single `command` string. For example, `execa('echo', ['unicorns'])` is the same as `execa.command('echo unicorns')`.

	If the file or an argument contains spaces, they must be escaped with backslashes. This matters especially if `command` is not a constant but a variable, for example with `__dirname` or `process.cwd()`. Except for spaces, no escaping/quoting is needed.

	The `shell` option must be used if the `command` uses shell-specific features, as opposed to being a simple `file` followed by its `arguments`.

	@param command - The program/script to execute and its arguments.
	@returns A [`child_process` instance](https://nodejs.org/api/child_process.html#child_process_class_childprocess), which is enhanced to also be a `Promise` for a result `Object` with `stdout` and `stderr` properties.

	@example
	```
	import execa from 'execa';

	(async () => {
		const {stdout} = await execa.command('echo unicorns');
		console.log(stdout);
		//=> 'unicorns'
	})();
	```
	*/
	command(command: string, options?: execa.Options): execa.ExecaChildProcess;
	command(command: string, options?: execa.Options<null>): execa.ExecaChildProcess<Buffer>;

	/**
	Same as `execa.command()` but synchronous.

	@param command - The program/script to execute and its arguments.
	@returns A result `Object` with `stdout` and `stderr` properties.
	*/
	commandSync(command: string, options?: execa.SyncOptions): execa.ExecaSyncReturnValue;
	commandSync(command: string, options?: execa.SyncOptions<null>): execa.ExecaSyncReturnValue<Buffer>;

	/**
	Execute a Node.js script as a child process.

	Same as `execa('node', [scriptPath, ...arguments], options)` except (like [`child_process#fork()`](https://nodejs.org/api/child_process.html#child_process_child_process_fork_modulepath_args_options)):
		- the current Node version and options are used. This can be overridden using the `nodePath` and `nodeArguments` options.
		- the `shell` option cannot be used
		- an extra channel [`ipc`](https://nodejs.org/api/child_process.html#child_process_options_stdio) is passed to [`stdio`](#stdio)

	@param scriptPath - Node.js script to execute.
	@param arguments - Arguments to pass to `scriptPath` on execution.
	@returns A [`child_process` instance](https://nodejs.org/api/child_process.html#child_process_class_childprocess), which is enhanced to also be a `Promise` for a result `Object` with `stdout` and `stderr` properties.
	*/
	node(
		scriptPath: string,
		arguments?: readonly string[],
		options?: execa.NodeOptions
	): execa.ExecaChildProcess;
	node(
		scriptPath: string,
		arguments?: readonly string[],
		options?: execa.Options<null>
	): execa.ExecaChildProcess<Buffer>;
	node(scriptPath: string, options?: execa.Options): execa.ExecaChildProcess;
	node(scriptPath: string, options?: execa.Options<null>): execa.ExecaChildProcess<Buffer>;
};

export = execa;
