"use strict";

const ValidationError = require("@validatem/error");
const isStream = require("is-stream");

module.exports = {
	any: function (value) {
		if (!isStream(value)) {
			return new ValidationError("Must be a Node.js stream");
		}
	},
	readable: function (value) {
		if (!isStream.readable(value) || isStream.writable(value)) {
			return new ValidationError("Must be a Node.js Readable stream");
		}
	},
	anyReadable: function (value) {
		if (!isStream.readable(value)) {
			return new ValidationError("Must be a Node.js stream that can be read from");
		}
	},
	writable: function (value) {
		if (!isStream.writable(value) || isStream.readable(value)) {
			return new ValidationError("Must be a Node.js Writable stream");
		}
	},
	anyWritable: function (value) {
		if (!isStream.writable(value)) {
			return new ValidationError("Must be a Node.js stream that can be written to");
		}
	},
	duplex: function (value) {
		if (!isStream.duplex(value) || isStream.transform(value)) {
			return new ValidationError("Must be a Node.js Duplex stream");
		}
	},
	anyDuplex: function (value) {
		if (!isStream.duplex(value)) {
			return new ValidationError("Must be a Node.js Duplex-based stream (eg. a Transform stream)");
		}
	},
	transform: function (value) {
		if (!isStream.transform(value)) {
			return new ValidationError("Must be a Node.js Transform stream");
		}
	}
};