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

/**
 * ACQUIS_Brevo
 *
 * Integrates with Brevo (formerly Sendinblue) Contacts API v3.
 * Supports contact creation/update, list assignment, and double opt-in.
 */
class ACQUIS_Brevo {

    const API_BASE = 'https://api.brevo.com/v3';

    /**
     * Subscribe a lead to the configured Brevo list.
     *
     * @param  int    $lead_id
     * @param  string $email
     * @param  string $full_name
     * @return array  ['success' => bool, 'message' => string]
     */
    public static function subscribe( $lead_id, $email, $full_name ) {
        if ( ! self::is_enabled() ) {
            return array( 'success' => false, 'message' => 'Brevo 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_key    =get_option( 'acquis_brevo_api_key', '' );
        $list_id    = (int) get_option( 'acquis_brevo_list_id', 0 );
        $dbl_optin  = (bool) get_option( 'acquis_brevo_double_optin', false );

        if ( empty( $api_key ) ) {
            return array( 'success' => false, 'message' => 'Brevo API key not configured.' );
        }

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

        if ( $dbl_optin && $list_id ) {
            // Use Brevo double opt-in endpoint
            return self::double_optin_subscribe( $lead_id, $email, $fname, $lname, $list_id, $api_key );
        }

        // Standard create/update contact
        $payload = array(
            'email'      => $email,
            'attributes' => array(
                'FIRSTNAME' => $fname,
                'LASTNAME'  => $lname,
            ),
            'updateEnabled' => true, // update if exists
        );

        if ( $list_id ) {
            $payload['listIds'] = array( $list_id );
        }

        $response = self::api_request( 'POST', self::API_BASE . '/contacts', $payload, $api_key );
        $success  = in_array( $response['http_code'] ?? 0, array( 200, 201, 204 ), true );

        if ( ! $success && ( $response['http_code'] ?? 0 ) === 400 ) {
            // Contact may already exist attempt PATCH update
            $encoded  = rawurlencode( $email );
            $response = self::api_request( 'PUT', self::API_BASE . '/contacts/' . $encoded, $payload, $api_key );
            $success  = in_array( $response['http_code'] ?? 0, array( 200, 201, 204 ), true );
        }

        $message = $success
            ? "Subscribed to Brevo list {$list_id}."
            : ( $response['body']['message'] ?? 'Unknown Brevo API error.' );

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

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

    /**
     * Trigger Brevo's native double opt-in flow.
     */
    private static function double_optin_subscribe( $lead_id, $email, $fname, $lname, $list_id, $api_key ) {
        // Brevo requires a DOI template configured in your account
        $doi_template_id = (int) get_option( 'acquis_brevo_doi_template_id', 0 );
        $redirect_url    = esc_url_raw( get_option( 'acquis_brevo_doi_redirect', home_url( '/' ) ) );

        if ( ! $doi_template_id ) {
            // Fallback to regular subscribe
            return self::subscribe( $lead_id, $email, "{$fname} {$lname}" );
        }

        $payload = array(
            'email'             => $email,
            'attributes'        => array( 'FIRSTNAME' => $fname, 'LASTNAME' => $lname ),
            'includeListIds'    => array( $list_id ),
            'templateId'        => $doi_template_id,
            'redirectionUrl'    => $redirect_url,
        );

        $response = self::api_request( 'POST', self::API_BASE . '/contacts/doubleOptinConfirmation', $payload, $api_key );
        $success  = in_array( $response['http_code'] ?? 0, array( 200, 201, 204 ), true );

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

        return array(
            'success' => $success,
            'message' => $success ? 'Brevo double opt-in confirmation sent.' : ( $response['body']['message'] ?? 'Brevo DOI failed.' ),
        );
    }

    /**
     * Test API key validity.
     *
     * @param  string $api_key
     * @return array  ['success' => bool, 'message' => string]
     */
    public static function test_connection( $api_key ) {
        $response = self::api_request( 'GET', self::API_BASE . '/account', array(), $api_key );
        $success  = ( $response['http_code'] ?? 0 ) === 200;
        return array(
            'success' => $success,
            'message' => $success
                ? ( 'Connected as: ' . ( $response['body']['email'] ?? 'unknown' ) )
                : ( $response['body']['message'] ?? 'Invalid Brevo API key.' ),
        );
    }

    /**
     * Fetch available contact lists for the admin dropdown.
     *
     * @param  string $api_key
     * @return array  [['id' => ..., 'name' => ...], ...]
     */
    public static function get_lists( $api_key ) {
        $response = self::api_request( 'GET', self::API_BASE . '/contacts/lists?limit=50', array(), $api_key );
        if ( empty( $response['body']['lists'] ) ) return array();
        return array_map( function( $list ) {
            return array( 'id' => $list['id'], 'name' => $list['name'] );
        }, $response['body']['lists'] );
    }

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

    /**
     * Shared HTTP helper.
     */
    private static function api_request( $method, $url, $body, $api_key ) {
        $args = array(
            'method'  => strtoupper( $method ),
            'headers' => array(
                'api-key'      => $api_key,
                'Content-Type' => 'application/json',
                'Accept'       => 'application/json',
            ),
            '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 );
    }
}