<?php
/**
 * Rewrite endpoint handler — serves /md/ URLs as plain text Markdown.
 *
 * @package AJW_AI_Markdown_Page_Widget
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Class AJWA_Endpoint
 */
class AJWA_Endpoint {

	/**
	 * Register hooks.
	 */
	public static function init() {
		add_action( 'init',              array( __CLASS__, 'add_rewrite_endpoint' ) );
		add_action( 'template_redirect', array( __CLASS__, 'handle_request' ) );
		add_action( 'wp_ajax_nopriv_ajwa_get_md', array( __CLASS__, 'ajax_get_md' ) );
		add_action( 'wp_ajax_ajwa_get_md',        array( __CLASS__, 'ajax_get_md' ) );
	}

	/**
	 * Register the /md/ rewrite endpoint on all permalink structures.
	 */
	public static function add_rewrite_endpoint() {
		add_rewrite_endpoint( 'md', EP_ALL );
	}

	/**
	 * Handle /md/ requests — serve Markdown as plain text.
	 */
	public static function handle_request() {
		global $wp_query;

		if ( ! isset( $wp_query->query_vars['md'] ) ) {
			return;
		}

		$post_id = self::get_current_post_id();

		if ( ! $post_id ) {
			status_header( 404 );
			header( 'Content-Type: text/plain; charset=UTF-8' );
			echo "# 404 Not Found\n\nNo content found for this URL.";
			exit;
		}

		$settings      = ajwa_get_settings();
		$enabled_types = $settings['enabled_post_types'] ?? array();
		$post          = get_post( $post_id );

		if ( ! $post || ! in_array( $post->post_type, $enabled_types, true ) ) {
			status_header( 403 );
			header( 'Content-Type: text/plain; charset=UTF-8' );
			echo "# Access Denied\n\nThis page is not available as Markdown.";
			exit;
		}

		$md = AJWA_Markdown::get_or_generate( $post_id );

		if ( ! $md ) {
			status_header( 500 );
			header( 'Content-Type: text/plain; charset=UTF-8' );
			echo "# Error\n\nCould not generate Markdown for this page.";
			exit;
		}

		status_header( 200 );
		header( 'Content-Type: text/plain; charset=UTF-8' );
		header( 'X-Robots-Tag: noindex, nofollow' );
		nocache_headers();

		// Output is plain text Markdown — not HTML, no escaping needed here.
		// phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
		echo $md;
		exit;
	}

	/**
	 * Get the post ID for the current request.
	 *
	 * @return int Post ID or 0.
	 */
	private static function get_current_post_id() {
		$post_id = get_queried_object_id();
		if ( $post_id ) {
			return $post_id;
		}
		global $post;
		if ( $post && $post->ID ) {
			return $post->ID;
		}
		return 0;
	}

	/**
	 * AJAX: get Markdown content for a post (used by copy button on frontend).
	 */
	public static function ajax_get_md() {
		// Verify nonce passed from frontend JS.
		if ( ! isset( $_POST['nonce'] ) || ! wp_verify_nonce( sanitize_text_field( wp_unslash( $_POST['nonce'] ) ), 'ajwa_frontend_nonce' ) ) {
			wp_send_json_error( 'Invalid nonce.' );
		}

		$post_id = absint( wp_unslash( $_POST['post_id'] ?? 0 ) );
		if ( ! $post_id ) {
			wp_send_json_error( 'No post ID.' );
		}

		$settings      = ajwa_get_settings();
		$enabled_types = $settings['enabled_post_types'] ?? array();
		$post          = get_post( $post_id );

		if ( ! $post || ! in_array( $post->post_type, $enabled_types, true ) ) {
			wp_send_json_error( 'Not enabled for this post type.' );
		}

		$md = AJWA_Markdown::get_or_generate( $post_id );
		if ( $md ) {
			wp_send_json_success( array( 'md' => $md ) );
		} else {
			wp_send_json_error( 'Failed to generate.' );
		}
	}
}