<?php

namespace Nest\Cli\Commands;

/**
 * A parameter definition object.
 */
class ParameterDefinition
{
	/**
	 * Parameter description.
	 * @var string|null
	 */
	protected ?string $description = null;

	/**
	 * Set if the parameter is optional or not. By default, it is NOT optional.
	 * @var bool
	 */
	protected bool $optional = false;

	/**
	 * Set the description of the parameter.
	 * @param string $description The description of the parameter.
	 * @return $this
	 */
	public function description(string $description): static
	{
		// Set description.
		$this->description = $description;
		return $this;
	}

	/**
	 * Set the parameter as optional (or not).
	 * @param bool $optional True to set the parameter as optional.
	 * @return $this
	 */
	public function optional(bool $optional = true): static
	{
		$this->optional = $optional;
		return $this;
	}

	/**
	 * Set the parameter as required.
	 * @return $this
	 */
	public function require(): static
	{
		return $this->optional(false);
	}

	/**
	 * Get parameter description.
	 * @return string
	 */
	public function getDescription(): string
	{
		return $this->description ?? "";
	}

	/**
	 * Determine if the parameter is required or not.
	 * @return bool True if the parameter is required.
	 */
	public function isRequired(): bool
	{
		return !$this->optional;
	}
}