<?php
/**
 * Aiforya_Multi_Author_Ajax — points d'entrée AJAX du flux éditorial (version gratuite, sans IA).
 *
 * Assignation, changement de statut, gestion des co-auteurs et enregistrement
 * des réglages locaux. Aucun appel réseau, aucun test de clé API.
 *
 * @package aiforya-multi-author
 */

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

if ( class_exists( 'Aiforya_Multi_Author_Ajax', false ) ) {
    return;
}

class Aiforya_Multi_Author_Ajax {

    /** @var self|null Singleton instance. */
    private static ?self $instance = null;

    public static function get_instance(): self {
        if ( self::$instance === null ) {
            self::$instance = new self();
        }
        return self::$instance;
    }

    public function __construct() {
        add_action( 'wp_ajax_aiforya_ma_assign_article', [ $this, 'handle_assign_article' ] );
        add_action( 'wp_ajax_aiforya_ma_change_status',  [ $this, 'handle_change_status' ] );
        add_action( 'wp_ajax_aiforya_ma_add_coauthor',   [ $this, 'handle_add_coauthor' ] );
        add_action( 'wp_ajax_aiforya_ma_remove_coauthor', [ $this, 'handle_remove_coauthor' ] );
        add_action( 'wp_ajax_aiforya_ma_save_settings',  [ $this, 'handle_save_settings' ] );
    }

    private function guard( string $capability = 'edit_posts' ): bool {
        check_ajax_referer( 'aiforya_ma_admin', 'nonce' );
        if ( ! current_user_can( $capability ) ) {
            wp_send_json_error( [ 'message' => __( 'Permission denied.', 'aiforya-multi-author' ) ], 403 );
            return false;
        }
        return true;
    }

    public function handle_assign_article(): void {
        if ( ! $this->guard( 'edit_others_posts' ) ) {
            return;
        }

        $post_id = isset( $_POST['post_id'] ) ? intval( wp_unslash( $_POST['post_id'] ) ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.
        $user_id = isset( $_POST['user_id'] ) ? intval( wp_unslash( $_POST['user_id'] ) ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.

        if ( ! $post_id || ! $user_id ) {
            wp_send_json_error( [ 'message' => __( 'Invalid parameters.', 'aiforya-multi-author' ) ], 400 );
            return;
        }

        $user = get_user_by( 'id', $user_id );
        if ( ! $user ) {
            wp_send_json_error( [ 'message' => __( 'User not found.', 'aiforya-multi-author' ) ], 404 );
            return;
        }

        $workflow = Aiforya_Multi_Author_Workflow::get_instance();
        if ( ! $workflow->assign_article( $post_id, $user_id ) ) {
            wp_send_json_error( [ 'message' => __( 'Assignment failed.', 'aiforya-multi-author' ) ], 500 );
            return;
        }

        wp_send_json_success( [
            'message'   => sprintf(
                /* translators: %s: author display name. */
                __( 'Post assigned to %s.', 'aiforya-multi-author' ),
                $user->display_name
            ),
            'post_id'   => $post_id,
            'user_id'   => $user_id,
            'user_name' => $user->display_name,
        ] );
    }

    public function handle_change_status(): void {
        if ( ! $this->guard( 'edit_posts' ) ) {
            return;
        }

        $post_id    = isset( $_POST['post_id'] ) ? intval( wp_unslash( $_POST['post_id'] ) ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.
        $new_status = isset( $_POST['new_status'] ) ? sanitize_text_field( wp_unslash( $_POST['new_status'] ) ) : ''; // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.

        if ( ! $post_id || '' === $new_status ) {
            wp_send_json_error( [ 'message' => __( 'Invalid parameters.', 'aiforya-multi-author' ) ], 400 );
            return;
        }

        $workflow = Aiforya_Multi_Author_Workflow::get_instance();
        if ( ! in_array( $new_status, $workflow->get_workflow_statuses(), true ) ) {
            wp_send_json_error( [ 'message' => __( 'Invalid status.', 'aiforya-multi-author' ) ], 400 );
            return;
        }

        if ( ! $workflow->change_article_status( $post_id, $new_status ) ) {
            wp_send_json_error( [ 'message' => __( 'Status change failed.', 'aiforya-multi-author' ) ], 500 );
            return;
        }

        wp_send_json_success( [
            'message'    => __( 'Status updated.', 'aiforya-multi-author' ),
            'post_id'    => $post_id,
            'new_status' => $new_status,
        ] );
    }

    public function handle_add_coauthor(): void {
        if ( ! $this->guard( 'edit_others_posts' ) ) {
            return;
        }

        $post_id = isset( $_POST['post_id'] ) ? intval( wp_unslash( $_POST['post_id'] ) ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.
        $user_id = isset( $_POST['user_id'] ) ? intval( wp_unslash( $_POST['user_id'] ) ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.

        if ( ! $post_id || ! $user_id ) {
            wp_send_json_error( [ 'message' => __( 'Invalid parameters.', 'aiforya-multi-author' ) ], 400 );
            return;
        }

        $db     = Aiforya_Multi_Author_Db::get_instance();
        $result = $db->add_coauthor( $post_id, $user_id );
        if ( is_wp_error( $result ) ) {
            wp_send_json_error( [ 'message' => $result->get_error_message() ], 500 );
            return;
        }

        wp_send_json_success( [ 'message' => __( 'Co-author added.', 'aiforya-multi-author' ), 'post_id' => $post_id, 'user_id' => $user_id ] );
    }

    public function handle_remove_coauthor(): void {
        if ( ! $this->guard( 'edit_others_posts' ) ) {
            return;
        }

        $post_id = isset( $_POST['post_id'] ) ? intval( wp_unslash( $_POST['post_id'] ) ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.
        $user_id = isset( $_POST['user_id'] ) ? intval( wp_unslash( $_POST['user_id'] ) ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.

        if ( ! $post_id || ! $user_id ) {
            wp_send_json_error( [ 'message' => __( 'Invalid parameters.', 'aiforya-multi-author' ) ], 400 );
            return;
        }

        $db = Aiforya_Multi_Author_Db::get_instance();
        if ( ! $db->remove_coauthor( $post_id, $user_id ) ) {
            wp_send_json_error( [ 'message' => __( 'Removing the co-author failed.', 'aiforya-multi-author' ) ], 500 );
            return;
        }

        wp_send_json_success( [ 'message' => __( 'Co-author removed.', 'aiforya-multi-author' ), 'post_id' => $post_id, 'user_id' => $user_id ] );
    }

    public function handle_save_settings(): void {
        if ( ! $this->guard( 'manage_options' ) ) {
            return;
        }

        $db      = Aiforya_Multi_Author_Db::get_instance();
        $current = $db->get_settings();

        $settings = [
            'show_byline'           => ! empty( $_POST['show_byline'] ), // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.
            'notifications_enabled' => ! empty( $_POST['notifications_enabled'] ), // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.
            'cleanup_on_uninstall'  => ! empty( $_POST['cleanup_on_uninstall'] ), // phpcs:ignore WordPress.Security.NonceVerification.Missing -- nonce verifie par guard() (check_ajax_referer 'aiforya_ma_admin'), appele en premiere instruction de ce handler.
        ];

        $db->save_settings( wp_parse_args( $settings, $current ) );

        wp_send_json_success( [ 'message' => __( 'Settings saved.', 'aiforya-multi-author' ) ] );
    }
}