<?php
/**
 * [stand_button], [stand_card] and [stand_chatbox] shortcodes.
 *
 * @package StandChat
 */

namespace StandChat;

defined( 'ABSPATH' ) || exit;

/**
 * Shortcodes for the Classic editor, widgets and page builders.
 *
 * [stand_card] uses child shortcodes for its controls. They don't print
 * anything themselves: the card collects them and prints them as direct
 * children, so automatic paragraphs can't wrap the markers.
 */
final class Shortcodes {

	/**
	 * Front-end printer, told when a page needs the widget.
	 *
	 * @var Frontend
	 */
	private $frontend;

	/**
	 * Controls collected from the innermost [stand_card] being rendered.
	 *
	 * @var array<int, array<string, string>>
	 */
	private $card_stack = array();

	/**
	 * How many chatboxes without a key, by the key they'd share, this request
	 * printed.
	 *
	 * @var array<string, int>
	 */
	private $chatbox_keys = array();

	/**
	 * Constructor.
	 *
	 * @param Frontend $frontend Front-end printer.
	 */
	public function __construct( Frontend $frontend ) {
		$this->frontend = $frontend;
	}

	/**
	 * Hooks.
	 */
	public function register(): void {
		add_shortcode( 'stand_button', array( $this, 'button' ) );
		add_shortcode( 'stand_card', array( $this, 'card' ) );
		add_shortcode( 'stand_chatbox', array( $this, 'chatbox' ) );
		add_shortcode( 'stand_action', array( $this, 'card_child' ) );
		add_shortcode( 'stand_visitor_message', array( $this, 'card_child' ) );
		add_shortcode( 'stand_dismiss', array( $this, 'card_child' ) );
		add_filter( 'the_content', array( self::class, 'unwrap_paragraphs' ), 12 );
		add_filter( 'widget_text_content', array( self::class, 'unwrap_paragraphs' ), 12 );
	}

	/**
	 * [stand_button].
	 *
	 * @param array<string, string>|string $atts    Attributes.
	 * @param string|null                  $content Label.
	 */
	public function button( $atts, $content = null ): string {
		$atts = shortcode_atts(
			array(
				'label'        => '',
				'show_when'    => 'either',
				'avatar'       => 'yes',
				'greeting'     => '',
				'prompt'       => '',
				'analytics_id' => '',
				'class'        => '',
			),
			is_array( $atts ) ? $atts : array(),
			'stand_button'
		);
		$this->frontend->content_needs_widget();

		$label = '' !== trim( (string) $content ) ? wp_strip_all_tags( (string) $content ) : $atts['label'];
		return Markup::button(
			array(
				'label'       => $label,
				'showWhen'    => $atts['show_when'],
				'avatar'      => self::flag( $atts['avatar'] ),
				'greeting'    => $atts['greeting'],
				'prompt'      => $atts['prompt'],
				'analyticsId' => $atts['analytics_id'],
			),
			self::wrapper( 'wp-block-stand-chat-stand-button', $atts['class'] )
		);
	}

	/**
	 * [stand_card].
	 *
	 * @param array<string, string>|string $atts    Attributes.
	 * @param string|null                  $content Body with optional child shortcodes.
	 */
	public function card( $atts, $content = null ): string {
		$atts = shortcode_atts(
			array(
				'show_when'     => 'either',
				'greeting'      => '',
				'prompt'        => '',
				'analytics_id'  => '',
				'identity'      => 'avatar name',
				'theme'         => 'outlined',
				'spotlight'     => 'no',
				'action'        => '',
				'action_type'   => 'button',
				'message'       => '',
				'message_field' => 'no',
				'placeholder'   => '',
				'footer'        => '',
				'image'         => '',
				'image_alt'     => '',
				'class'         => '',
			),
			is_array( $atts ) ? $atts : array(),
			'stand_card'
		);
		$this->frontend->content_needs_widget();

		$this->card_stack[] = array();
		$body               = do_shortcode( (string) $content );
		$children           = array_pop( $this->card_stack );
		$body               = wp_kses_post( self::balance( $body ) );

		$message_mode = 'none';
		$message      = '' !== ( $children['stand_visitor_message'] ?? '' ) ? $children['stand_visitor_message'] : $atts['message'];
		if ( self::flag( $atts['message_field'] ) ) {
			$message_mode = 'field';
		} elseif ( '' !== $message ) {
			$message_mode = 'fixed';
		}

		return Markup::card(
			array(
				'showWhen'         => $atts['show_when'],
				'greeting'         => $atts['greeting'],
				'prompt'           => $atts['prompt'],
				'analyticsId'      => $atts['analytics_id'],
				'identity'         => $atts['identity'],
				'theme'            => $atts['theme'],
				'spotlight'        => self::flag( $atts['spotlight'] ),
				'actionType'       => $atts['action_type'],
				'actionLabel'      => '' !== ( $children['stand_action'] ?? '' ) ? $children['stand_action'] : $atts['action'],
				'messageMode'      => $message_mode,
				'visitorMessage'   => $message,
				'fieldPlaceholder' => $atts['placeholder'],
				'dismissText'      => $children['stand_dismiss'] ?? '',
				'footer'           => $atts['footer'],
				'mediaUrl'         => $atts['image'],
				'mediaAlt'         => $atts['image_alt'],
			),
			$body,
			self::wrapper( 'wp-block-stand-chat-stand-card', $atts['class'] )
		);
	}

	/**
	 * [stand_action], [stand_visitor_message] and [stand_dismiss] inside a card.
	 *
	 * @param array<string, string>|string $atts    Unused.
	 * @param string|null                  $content Text.
	 * @param string                       $tag     Shortcode name.
	 */
	public function card_child( $atts, $content = null, $tag = '' ): string {
		unset( $atts );
		if ( empty( $this->card_stack ) ) {
			return '';
		}
		$last                              = count( $this->card_stack ) - 1;
		$this->card_stack[ $last ][ $tag ] = trim( wp_strip_all_tags( (string) $content ) );
		return '';
	}

	/**
	 * [stand_chatbox].
	 *
	 * @param array<string, string>|string $atts    Attributes.
	 * @param string|null                  $content Intro HTML.
	 */
	public function chatbox( $atts, $content = null ): string {
		$atts = shortcode_atts(
			array(
				'greeting'       => '',
				'placeholder'    => '',
				'send_label'     => '',
				'floating'       => 'no',
				'show_header'    => 'no',
				'height'         => '',
				'show_when'      => 'either',
				'shared_session' => 'no',
				'prompt'         => '',
				'analytics_id'   => '',
				'key'            => '',
				'label'          => '',
				'class'          => '',
			),
			is_array( $atts ) ? $atts : array(),
			'stand_chatbox'
		);
		$this->frontend->content_needs_widget();

		$intro = wp_kses_post( self::balance( do_shortcode( (string) $content ) ) );
		return Markup::chatbox(
			array(
				'greeting'      => $atts['greeting'],
				'placeholder'   => $atts['placeholder'],
				'sendLabel'     => $atts['send_label'],
				'floating'      => self::flag( $atts['floating'] ),
				'showHeader'    => self::flag( $atts['show_header'] ),
				'heightMode'    => 'grow' === $atts['height'] ? 'grow' : 'capped',
				'maxHeight'     => is_numeric( $atts['height'] ) ? (int) $atts['height'] : null,
				'showWhen'      => $atts['show_when'],
				'sharedSession' => self::flag( $atts['shared_session'] ),
				'prompt'        => $atts['prompt'],
				'analyticsId'   => $atts['analytics_id'],
				'sessionKey'    => '' !== $atts['key'] ? $atts['key'] : $this->chatbox_key( (string) $content ),
				'label'         => $atts['label'],
			),
			$intro,
			self::wrapper( 'wp-block-stand-chat-stand-chatbox', $atts['class'] )
		);
	}

	/**
	 * The conversation key of a [stand_chatbox] without one: from the page and
	 * the chatbox's intro, and, for another with the same intro on the page,
	 * its place among them, so the two don't share a visitor's conversation.
	 *
	 * @param string $content Intro HTML.
	 */
	private function chatbox_key( string $content ): string {
		$key                        = 'wp-' . get_the_ID() . '-' . substr( md5( $content ), 0, 6 );
		$this->chatbox_keys[ $key ] = ( $this->chatbox_keys[ $key ] ?? 0 ) + 1;
		return 1 === $this->chatbox_keys[ $key ] ? $key : $key . '-' . $this->chatbox_keys[ $key ];
	}

	/**
	 * Removes the paragraph WordPress wraps around a card or chatbox.
	 *
	 * Automatic paragraphs run before shortcodes, so an enclosing shortcode on
	 * its own lines ends up as <p><stand-card>…</stand-card></p>. Browsers close
	 * that paragraph at the card's first block element, which would end the
	 * card early.
	 *
	 * @param string $html Content after shortcodes ran.
	 */
	public static function unwrap_paragraphs( $html ) {
		if ( ! is_string( $html ) || false === strpos( $html, '<stand-' ) ) {
			return $html;
		}
		$html = preg_replace( '#<p>\s*(<stand-(?:card|chatbox)\b)#', '$1', $html );
		return preg_replace( '#(</stand-(?:card|chatbox)>)\s*(?:<br\s*/?>\s*)?</p>#', '$1', (string) $html );
	}

	/**
	 * Tidies enclosed content: automatic paragraphs leave a dangling </p> at the
	 * start and <p> at the end when the shortcode spans several paragraphs.
	 *
	 * @param string $html Enclosed content.
	 */
	private static function balance( string $html ): string {
		$html = trim( $html );
		$html = preg_replace( '#^(?:</p>|<br\s*/?>|\s)+#i', '', $html );
		$html = preg_replace( '#(?:<p>|<br\s*/?>|\s)+$#i', '', (string) $html );
		$html = preg_replace( '#<p>\s*</p>#i', '', (string) $html );
		return force_balance_tags( (string) $html );
	}

	/**
	 * Truthy shortcode values: yes, true, 1, on.
	 *
	 * @param mixed $value Raw value.
	 */
	private static function flag( $value ): bool {
		return in_array( strtolower( trim( (string) $value ) ), array( 'yes', 'true', '1', 'on' ), true );
	}

	/**
	 * Wrapper attributes with the block class and the author's classes.
	 *
	 * @param string $base  Block class.
	 * @param string $extra Classes from the shortcode.
	 * @return array<string, string>
	 */
	private static function wrapper( string $base, string $extra ): array {
		$classes = array_filter( array_map( 'sanitize_html_class', preg_split( '/\s+/', $base . ' ' . $extra ) ) );
		return array( 'class' => implode( ' ', $classes ) );
	}
}