<?php
if ( ! defined( 'ABSPATH' ) ) exit;

/**
 * ACQUIS_Mailwizz
 *
 * Full integration with MailWizz EMA REST API v1.
 *
 * Features:
 *  - Subscribe contacts to a specific list (list uid)
 *  - Custom field mapping (WordPress option → MailWizz field tag)
 *  - Double opt-in support
 *  - Tag assignment via API
 *  - HMAC-SHA1 signed requests using Public + Private keys
 */
class ACQUIS_Mailwizz {

    /**
     * Subscribe a lead to the configured MailWizz list.
     *
     * @param  int    $lead_id
     * @param  string $email
     * @param  string $full_name
     * @param  array  $extra_fields  Additional mapped fields ['TAG' => 'value']
     * @return array  ['success' => bool, 'message' => string]
     */
    public static function subscribe( $lead_id, $email, $full_name, $extra_fields = array() ) {
        if ( ! self::is_enabled() ) {
            return array( 'success' => false, 'message' => 'MailWizz integration disabled.' );
        }
        // Adding an address to a mailing list is marketing: an unsubscribed address is never re-added.
        if ( ! apply_filters( 'acquis_marketing_allowed', true, $email ) ) {
            return array( 'success' => false, 'message' => 'Skipped: this address unsubscribed from marketing.' );
        }

        $api_url    = untrailingslashit( get_option( 'acquis_mailwizz_api_url', '' ) );
        $public_key  = get_option( 'acquis_mailwizz_public_key', '' );
        $private_key = get_option( 'acquis_mailwizz_private_key', '' );
        $list_uid    = get_option( 'acquis_mailwizz_list_uid', '' );
        $double_optin= (bool) get_option( 'acquis_mailwizz_double_optin', false );
        $field_map   = get_option( 'acquis_mailwizz_custom_fields', array() );

        if ( empty( $api_url ) || empty( $public_key ) || empty( $private_key ) || empty( $list_uid ) ) {
            return array( 'success' => false, 'message' => 'MailWizz: missing API credentials or list UID.' );
        }

        // Parse first/last name
        $name_parts = explode( ' ', trim( $full_name ), 2 );
        $fname      = $name_parts[0];
        $lname      = isset( $name_parts[1] ) ? $name_parts[1] : '';

        // Build subscriber data
        $data = array(
            'EMAIL'    => $email,
            'FNAME'    => $fname,
            'LNAME'    => $lname,
        );

        // Apply custom field mapping from settings
        if ( ! empty( $field_map ) && is_array( $field_map ) ) {
            foreach ( $field_map as $mw_tag => $wp_value ) {
                $data[ sanitize_text_field( $mw_tag ) ] = sanitize_text_field( $wp_value );
            }
        }

        // Merge any runtime extra fields
        foreach ( $extra_fields as $tag => $value ) {
            $data[ sanitize_text_field( $tag ) ] = sanitize_text_field( $value );
        }

        $endpoint = "{$api_url}/lists/{$list_uid}/subscribers";
        $payload  = array(
            'subscriber' => $data,
        );

        // MailWizz also supports ?confirm_optin=yes on the URL
        if ( ! $double_optin ) {
            $endpoint .= '?confirm_optin=no';
        }

        $response = self::api_request( 'POST', $endpoint, $payload, $public_key, $private_key );

        $success = isset( $response['body']['status'] ) && $response['body']['status'] === 'success';

        if ( ! $success ) {
            // Some MailWizz versions return 'error' with a message
            $err_msg = $response['body']['error'] ?? ( $response['body']['message'] ?? 'Unknown MailWizz API error.' );
            // Handle "already subscribed" gracefully
            if ( stripos( $err_msg, 'already' ) !== false || $response['http_code'] === 409 ) {
                $success = true;
                $err_msg = 'Already subscribed record updated.';
            }
        }

        $message = $success
            ? ( $response['body']['message'] ?? "Subscribed to MailWizz list {$list_uid}." )
            : ( $response['body']['error']   ?? 'MailWizz subscription failed.' );

        ACQUIS_Database::log_integration(
            $lead_id, 'mailwizz',
            $success ? 'success' : 'failed',
            wp_json_encode( $response['body'] ?? array() )
        );

        return array( 'success' => $success, 'message' => $message );
    }

    /**
     * Ping the API to test credentials.
     *
     * @param  string $api_url
     * @param  string $public_key
     * @param  string $private_key
     * @return array  ['success' => bool, 'message' => string]
     */
    public static function test_connection( $api_url, $public_key, $private_key ) {
        $api_url  = untrailingslashit( $api_url );
        $endpoint = "{$api_url}/customers/profile";
        $response = self::api_request( 'GET', $endpoint, array(), $public_key, $private_key );
        $success  = in_array( $response['http_code'] ?? 0, array( 200, 201 ), true )
                    && isset( $response['body']['status'] )
                    && $response['body']['status'] === 'success';
        return array(
            'success' => $success,
            'message' => $success ? 'MailWizz connection successful.' : ( $response['body']['error'] ?? 'Connection failed.' ),
        );
    }

    /**
     * Fetch available lists for the admin dropdown.
     *
     * @param  string $api_url
     * @param  string $public_key
     * @param  string $private_key
     * @return array  [['uid' => ..., 'name' => ...], ...]
     */
    public static function get_lists( $api_url, $public_key, $private_key ) {
        $api_url  = untrailingslashit( $api_url );
        $response = self::api_request( 'GET', "{$api_url}/lists?per_page=100", array(), $public_key, $private_key );
        if ( empty( $response['body']['data']['records'] ) ) return array();
        return array_map( function( $list ) {
            return array( 'uid' => $list['list_uid'], 'name' => $list['name'] );
        }, $response['body']['data']['records'] );
    }

    public static function is_enabled() {
        return (bool) get_option( 'acquis_mailwizz_enabled', false );
    }

    /**
     * MailWizz uses HMAC-SHA1 signed requests.
     * Signature = base64(HMAC-SHA1(timestamp + "\n" + public_key, private_key))
     */
    private static function build_signature( $public_key, $private_key ) {
        $timestamp = (string) time();
        $signature = base64_encode( hash_hmac( 'sha1', $timestamp . "\n" . $public_key, $private_key, true ) );
        return array( 'timestamp' => $timestamp, 'signature' => $signature );
    }

    /**
     * Execute a signed API request.
     */
    private static function api_request( $method, $url, $body, $public_key, $private_key ) {
        $sig = self::build_signature( $public_key, $private_key );

        $headers = array(
            'X-MW-PUBLIC-KEY'   => $public_key,
            'X-MW-TIMESTAMP'    => $sig['timestamp'],
            'X-MW-SIGNATURE'    => $sig['signature'],
            'Content-Type'      => 'application/json',
            'Accept'            => 'application/json',
        );

        $args = array(
            'method'  => strtoupper( $method ),
            'headers' => $headers,
            'timeout' => 15,
        );

        if ( ! empty( $body ) ) {
            $args['body'] = wp_json_encode( $body );
        }

        $response  = wp_remote_request( $url, $args );
        $http_code = wp_remote_retrieve_response_code( $response );
        $raw_body  = wp_remote_retrieve_body( $response );
        $decoded   = json_decode( $raw_body, true );

        return array( 'http_code' => $http_code, 'body' => $decoded, 'raw' => $raw_body );
    }
}