<?php

namespace Slack\Blockkit\Blocks\Elements;

use \Exception;

use Slack\Blockkit\Element;

final class Button extends Element
{
	protected const LIMITS = [
		'action_id' => 255,
		'callback_id' => 255,
		'text' => 75,
		'url' => 3000,
		'value' => 2000,
	];

	public function __construct(Text $text,string $value,string $action_id)
	{
		parent::__construct();

		// Defaults
		$this->type = 'button';

		if ($text->type != 'plain_text')
			throw new Exception(sprintf('Text must be plain_text not %s',$text->type));

		if (strlen($text->text) > self::LIMITS['text'])
			throw new Exception(sprintf('Text must be %d chars or less',self::LIMITS['text']));

		$this->text = $text;

		$this->value = $this->validate('value',$value);
		$this->action_id = $this->validate('action_id',$action_id);
	}

	public static function item(Text $text,string $value,string $action_id): self
	{
		return new self($text,$value,$action_id);
	}

	/* OPTIONAL ITEMS */

	public function callback_id(string $string): self
	{
		$this->callback_id = $string;

		return $this;
	}

	public function confirm(Confirm $confirm): self
	{
		$this->confirm = $confirm;

		return $this;
	}

	public function style(string $string): self
	{
		if (! in_array($string,['default','primary','danger']))
			throw new Exception(sprintf('Unknown style %s',$string));

		$this->style = $string;

		return $this;
	}

	public function url(string $string): self
	{
		$this->url = $this->validate('url',$string);

		return $this;
	}
}