<?php
/**
 * Authentication handler for AiBlogPress plugin.
 *
 * Handles registration and login via AJAX.
 *
 * @package AiBlogWriter
 */

defined( 'ABSPATH' ) || exit;

class ABPW_Auth {

    /**
     * Constructor: register AJAX hooks.
     */
    public function __construct() {
        add_action( 'wp_ajax_abpw_register', array( $this, 'handle_register' ) );
        add_action( 'wp_ajax_abpw_login', array( $this, 'handle_login' ) );
        add_action( 'wp_ajax_abpw_confirm_status', array( $this, 'handle_confirm_status' ) );
        add_action( 'wp_ajax_abpw_store_credentials', array( $this, 'handle_store_credentials' ) );
        add_action( 'wp_ajax_abpw_resend_confirmation', array( $this, 'handle_resend_confirmation' ) );
    }

    /**
     * Handle registration AJAX request.
     */
    public function handle_register() {
        // Verify nonce.
        check_ajax_referer( 'abpw_auth_nonce', 'abpw_nonce' );

        // Check capability.
        if ( ! current_user_can( 'manage_options' ) ) {
            wp_send_json_error( array(
                'message' => __( 'You do not have permission to perform this action.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Sanitize input.
        $email            = isset( $_POST['email'] ) ? sanitize_email( wp_unslash( $_POST['email'] ) ) : '';
        $password         = isset( $_POST['password'] ) ? sanitize_text_field( wp_unslash( $_POST['password'] ) ) : '';
        $full_name        = isset( $_POST['full_name'] ) ? sanitize_text_field( wp_unslash( $_POST['full_name'] ) ) : '';
        $confirm_password = isset( $_POST['confirm_password'] ) ? sanitize_text_field( wp_unslash( $_POST['confirm_password'] ) ) : '';

        // Validate.
        if ( empty( $full_name ) ) {
            wp_send_json_error( array(
                'message' => __( 'Please enter your full name.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        if ( empty( $email ) || ! is_email( $email ) ) {
            wp_send_json_error( array(
                'message' => __( 'Please enter a valid email address.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        if ( empty( $password ) || strlen( $password ) < 8 ) {
            wp_send_json_error( array(
                'message' => __( 'Password must be at least 8 characters.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        if ( $password !== $confirm_password ) {
            wp_send_json_error( array(
                'message' => __( 'Passwords do not match.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Call the API.
        $response = ABPW_Api_Client::post_unauthenticated( '/auth/register', array(
            'email'            => $email,
            'password'         => $password,
            'confirm_password' => $confirm_password,
            'full_name'        => $full_name,
            'scope'            => 'full_free',
            'site_url'         => get_site_url(),
        ) );

        if ( is_wp_error( $response ) ) {
            $error_data = $response->get_error_data();
            $status     = isset( $error_data['status'] ) ? $error_data['status'] : 500;

            $send_data = array(
                'message' => $response->get_error_message(),
            );

            // Mark 409 as email_exists for special handling in JS.
            if ( 409 === $status ) {
                $send_data['code'] = 'email_exists';
            }

            wp_send_json_error( $send_data );
        }

        // Handle pending confirmation response.
        if ( isset( $response['status'] ) && 'pending_confirmation' === $response['status'] ) {
            wp_send_json_success( array(
                'status' => 'pending_confirmation',
                'email'  => $email,
            ) );
        }

        // Backward compat: if API returns api_key directly, store and redirect.
        $this->store_credentials( $response );

        wp_send_json_success( array(
            'redirect' => admin_url( 'admin.php?page=abp-writer-onboarding' ),
        ) );
    }

    /**
     * Handle login AJAX request.
     */
    public function handle_login() {
        // Verify nonce.
        check_ajax_referer( 'abpw_auth_nonce', 'abpw_nonce' );

        // Check capability.
        if ( ! current_user_can( 'manage_options' ) ) {
            wp_send_json_error( array(
                'message' => __( 'You do not have permission to perform this action.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Sanitize input.
        $email    = isset( $_POST['email'] ) ? sanitize_email( wp_unslash( $_POST['email'] ) ) : '';
        $password = isset( $_POST['password'] ) ? sanitize_text_field( wp_unslash( $_POST['password'] ) ) : '';

        // Validate.
        if ( empty( $email ) || ! is_email( $email ) ) {
            wp_send_json_error( array(
                'message' => __( 'Please enter a valid email address.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        if ( empty( $password ) || strlen( $password ) < 8 ) {
            wp_send_json_error( array(
                'message' => __( 'Password must be at least 8 characters.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Call the API.
        $response = ABPW_Api_Client::post_unauthenticated( '/auth/login', array(
            'email'    => $email,
            'password' => $password,
            'scope'    => 'full_free',
        ) );

        if ( is_wp_error( $response ) ) {
            wp_send_json_error( array(
                'message' => $response->get_error_message(),
            ) );
        }

        // Store credentials.
        $this->store_credentials( $response );

        // Check if user already has a config on the server (reconnect scenario).
        $config_response = ABPW_Api_Client::get( '/config' );
        if ( ! is_wp_error( $config_response )
            && isset( $config_response['config'] )
            && ! empty( $config_response['config'] )
        ) {
            update_option( 'aiblogpress_onboarding_complete', true );
        }

        // Determine redirect: onboarding or dashboard.
        $onboarding_complete = get_option( 'aiblogpress_onboarding_complete', false );
        $redirect = $onboarding_complete
            ? admin_url( 'admin.php?page=abp-writer' )
            : admin_url( 'admin.php?page=abp-writer-onboarding' );

        wp_send_json_success( array(
            'redirect' => $redirect,
        ) );
    }

    /**
     * Handle confirm-status AJAX request (polling for email confirmation).
     */
    public function handle_confirm_status() {
        // Verify nonce.
        check_ajax_referer( 'abpw_auth_nonce', 'abpw_nonce' );

        // Check capability.
        if ( ! current_user_can( 'manage_options' ) ) {
            wp_send_json_error( array(
                'message' => __( 'You do not have permission to perform this action.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Sanitize input.
        $email = isset( $_POST['email'] ) ? sanitize_email( wp_unslash( $_POST['email'] ) ) : '';

        if ( empty( $email ) || ! is_email( $email ) ) {
            wp_send_json_error( array(
                'message' => __( 'Please enter a valid email address.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Call the API.
        $response = ABPW_Api_Client::post_unauthenticated( '/auth/confirm-status', array(
            'email' => $email,
            'scope' => 'full_free',
        ) );

        if ( is_wp_error( $response ) ) {
            wp_send_json_error( array(
                'message' => $response->get_error_message(),
            ) );
        }

        wp_send_json_success( $response );
    }

    /**
     * Handle store-credentials AJAX request (after email confirmation).
     */
    public function handle_store_credentials() {
        // Verify nonce.
        check_ajax_referer( 'abpw_auth_nonce', 'abpw_nonce' );

        // Check capability.
        if ( ! current_user_can( 'manage_options' ) ) {
            wp_send_json_error( array(
                'message' => __( 'You do not have permission to perform this action.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Sanitize input.
        $api_key = isset( $_POST['api_key'] ) ? sanitize_text_field( wp_unslash( $_POST['api_key'] ) ) : '';
        $user_id = isset( $_POST['user_id'] ) ? sanitize_text_field( wp_unslash( $_POST['user_id'] ) ) : '';
        $scope   = isset( $_POST['scope'] ) ? sanitize_text_field( wp_unslash( $_POST['scope'] ) ) : '';

        if ( empty( $api_key ) ) {
            wp_send_json_error( array(
                'message' => __( 'API key is required.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Store credentials.
        $this->store_credentials( array(
            'api_key' => $api_key,
            'user_id' => $user_id,
            'scope'   => $scope,
        ) );

        wp_send_json_success( array(
            'redirect' => admin_url( 'admin.php?page=abp-writer-onboarding' ),
        ) );
    }

    /**
     * Handle resend confirmation email AJAX request.
     */
    public function handle_resend_confirmation() {
        // Verify nonce.
        check_ajax_referer( 'abpw_auth_nonce', 'abpw_nonce' );

        // Check capability.
        if ( ! current_user_can( 'manage_options' ) ) {
            wp_send_json_error( array(
                'message' => __( 'You do not have permission to perform this action.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Sanitize input.
        $email = isset( $_POST['email'] ) ? sanitize_email( wp_unslash( $_POST['email'] ) ) : '';

        if ( empty( $email ) || ! is_email( $email ) ) {
            wp_send_json_error( array(
                'message' => __( 'Please enter a valid email address.', 'abp-writer-ai-blog-generator' ),
            ) );
        }

        // Call the API.
        $response = ABPW_Api_Client::post_unauthenticated( '/auth/resend-confirmation', array(
            'email' => $email,
        ) );

        if ( is_wp_error( $response ) ) {
            wp_send_json_error( array(
                'message' => $response->get_error_message(),
            ) );
        }

        wp_send_json_success( array(
            'message' => __( 'Confirmation email sent! Check your inbox.', 'abp-writer-ai-blog-generator' ),
        ) );
    }

    /**
     * Store API credentials in wp_options.
     *
     * @param array $response API response with api_key, user_id, scope.
     */
    private function store_credentials( $response ) {
        if ( isset( $response['api_key'] ) ) {
            update_option( 'aiblogpress_api_key', sanitize_text_field( $response['api_key'] ) );
        }

        if ( isset( $response['user_id'] ) ) {
            update_option( 'aiblogpress_user_id', sanitize_text_field( $response['user_id'] ) );
        }

        if ( isset( $response['scope'] ) ) {
            update_option( 'aiblogpress_scope', sanitize_text_field( $response['scope'] ) );
        }
    }
}