<?php
/**
 * Prev/Next renderer and auto insertion logic.
 *
 * @package AHA_Prev_Next
 * @since 0.1.0
 */

if ( ! defined( 'WPINC' ) ) {
	die;
}

class AHA_Prev_Next_Renderer {

	/** @var AHA_Prev_Next_Renderer */
	private static $instance = null;

	/** @return AHA_Prev_Next_Renderer */
	public static function get_instance() {
		if ( is_null( self::$instance ) ) {
			self::$instance = new self();
		}
		return self::$instance;
	}

	public function __construct() {
		add_filter( 'the_content', array( $this, 'maybe_append_to_content' ), 25 );
		add_action( 'wp', array( $this, 'setup_woocommerce_hook' ) );
	}

	/**
	 * Append navigation to the end of content (Auto mode).
	 *
	 * @param string $content Post content.
	 * @return string
	 */
	public function maybe_append_to_content( $content ) {
		if ( is_admin() ) {
			return $content;
		}
		if ( ! function_exists( 'aha_prev_next_is_enabled' ) || ! aha_prev_next_is_enabled() ) {
			return $content;
		}
		if ( ! is_singular() || ! in_the_loop() || ! is_main_query() ) {
			return $content;
		}

		$settings = function_exists( 'aha_prev_next_get_settings' ) ? aha_prev_next_get_settings() : array();

		$post_type = get_post_type();
		$enabled_post_types = isset( $settings['enabled_post_types'] ) && is_array( $settings['enabled_post_types'] ) ? $settings['enabled_post_types'] : array( 'post', 'page' );

		/**
		 * Filter: whether auto insertion is enabled for the current post.
		 *
		 * @since 0.1.0
		 *
		 * @param bool $enabled Whether enabled.
		 * @param int  $post_id Current post ID.
		 */
		$enabled = in_array( $post_type, $enabled_post_types, true );
		$enabled = (bool) apply_filters( 'aha_prev_next_auto_enabled', $enabled, get_queried_object_id() );

		if ( ! $enabled ) {
			return $content;
		}

		$html = $this->render();
		if ( '' === $html ) {
			return $content;
		}

		$position = isset( $settings['position'] ) ? (string) $settings['position'] : 'below';
		if ( 'product' === $post_type ) {
			$position = isset( $settings['woo_position'] ) ? (string) $settings['woo_position'] : 'below';
		}

		if ( 'above' === $position ) {
			return $html . $content;
		}

		return $content . $html;
	}

	/**
	 * Render the navigation HTML.
	 *
	 * @param array $args Optional override args (used by shortcode).
	 * @return string
	 */
	public function render( $args = array() ) {
		if ( ! is_singular() ) {
			return '';
		}

		$post_id = get_queried_object_id();
		if ( ! $post_id ) {
			return '';
		}

		$settings = function_exists( 'aha_prev_next_get_settings' ) ? aha_prev_next_get_settings() : array();
		$settings = is_array( $settings ) ? $settings : array();

		$settings = array_merge( $settings, is_array( $args ) ? $args : array() );

		$prev = get_previous_post();
		$next = get_next_post();

		$prev_id = ( $prev && isset( $prev->ID ) ) ? (int) $prev->ID : 0;
		$next_id = ( $next && isset( $next->ID ) ) ? (int) $next->ID : 0;

		/**
		 * Filter adjacent post IDs (allowing custom post ordering or taxonomy selection rules).
		 *
		 * @since 0.1.0
		 *
		 * @param array $ids Array with keys prev and next.
		 * @param int   $post_id Current post ID.
		 */
		$ids = apply_filters(
			'aha_prev_next_adjacent_ids',
			array(
				'prev' => $prev_id,
				'next' => $next_id,
			),
			$post_id
		);

		$prev_id = isset( $ids['prev'] ) ? absint( $ids['prev'] ) : 0;
		$next_id = isset( $ids['next'] ) ? absint( $ids['next'] ) : 0;

		if ( ! $prev_id && ! $next_id ) {
			return '';
		}

		$position       = isset( $settings['position'] ) ? (string) $settings['position'] : 'below';
		if ( 'product' === get_post_type() ) {
			$woo_pos = isset( $settings['woo_position'] ) ? (string) $settings['woo_position'] : 'woocommerce_after_single_product';
			if ( in_array( $woo_pos, array( 'above', 'below' ), true ) ) {
				$position = $woo_pos;
			} else {
				$position = 'below';
			}
		}
		$show_thumb     = ! empty( $settings['show_thumbnail'] );
		$title_len      = ( isset( $settings['title_length'] ) && '' !== $settings['title_length'] ) ? absint( $settings['title_length'] ) : 40;

		$wrap_classes = array( 'aha-pn-wrap', 'aha-pn-pos-' . sanitize_html_class( $position ) );

		ob_start();
		/**
		 * Action before render.
		 *
		 * @since 0.1.0
		 */
		do_action( 'aha_prev_next_render_before' );

		include AHA_PREV_NEXT_PATH . 'templates/frontend/nav.php';

		/**
		 * Action after render.
		 *
		 * @since 0.1.0
		 */
		do_action( 'aha_prev_next_render_after' );
		return (string) ob_get_clean();
	}

	/**
	 * Setup WooCommerce hooks if on singular product and WooCommerce enabled.
	 *
	 * @return void
	 */
	public function setup_woocommerce_hook() {
		if ( is_admin() ) {
			return;
		}

		$settings = function_exists( 'aha_prev_next_get_settings' ) ? aha_prev_next_get_settings() : array();
		$post_type = get_post_type();
		$enabled_post_types = isset( $settings['enabled_post_types'] ) && is_array( $settings['enabled_post_types'] ) ? $settings['enabled_post_types'] : array( 'post', 'page' );

		if ( ! in_array( 'product', $enabled_post_types, true ) || ! is_singular( 'product' ) ) {
			return;
		}

		$woo_hook = isset( $settings['woo_position'] ) ? $settings['woo_position'] : 'woocommerce_after_single_product';

		if ( in_array( $woo_hook, array( 'above', 'below' ), true ) ) {
			// Let the_content filter handle it.
			return;
		}

		// Disable default post content injection on WooCommerce products.
		remove_filter( 'the_content', array( $this, 'maybe_append_to_content' ), 25 );

		if ( 'disable' !== $woo_hook && ! empty( $woo_hook ) ) {
			add_action( $woo_hook, array( $this, 'render_woo_navigation' ), 30 );
		}
	}

	/**
	 * Render WooCommerce navigation cards inside custom hook.
	 *
	 * @return void
	 */
	public function render_woo_navigation() {
		echo $this->render(); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
	}
}