<?php
/**
 * Twilio SMS Provider
 *
 * SMS provider implementation for Twilio
 */
class TWP_SMS_Provider_Twilio implements TWP_SMS_Provider {

    private $client;
    private $default_from_number;

    /**
     * Constructor
     */
    public function __construct() {
        $account_sid = get_option('twp_account_sid');
        $auth_token = get_option('twp_auth_token');
        $this->default_from_number = get_option('twp_sms_from_number');

        if (!empty($account_sid) && !empty($auth_token)) {
            $this->client = new Twilio\Rest\Client($account_sid, $auth_token);
        }
    }

    /**
     * Send an SMS message
     *
     * @param string $to_number Recipient phone number (E.164 format)
     * @param string $message Message body
     * @param string $from_number Sender phone number (E.164 format)
     * @return array Response array with 'success' and 'data' or 'error'
     */
    public function send_sms($to_number, $message, $from_number = null) {
        try {
            if (!$this->client) {
                return [
                    'success' => false,
                    'error' => 'Twilio client not initialized. Check API credentials.'
                ];
            }

            // Determine the from number
            $from = $from_number ?: $this->default_from_number;

            // Validate we have a from number
            if (empty($from)) {
                error_log('TWP SMS Error: No from number available. Please configure SMS notification number in settings.');
                return [
                    'success' => false,
                    'error' => 'No SMS from number configured. Please set SMS notification number in plugin settings.'
                ];
            }

            $sms = $this->client->messages->create(
                $to_number,
                [
                    'from' => $from,
                    'body' => $message
                ]
            );

            return [
                'success' => true,
                'provider' => 'twilio',
                'data' => [
                    'sid' => $sms->sid,
                    'status' => $sms->status,
                    'from' => $sms->from,
                    'to' => $sms->to,
                    'body' => $sms->body,
                    'price' => $sms->price,
                    'priceUnit' => $sms->priceUnit
                ]
            ];
        } catch (\Twilio\Exceptions\TwilioException $e) {
            return [
                'success' => false,
                'provider' => 'twilio',
                'error' => $e->getMessage(),
                'code' => $e->getCode()
            ];
        }
    }

    /**
     * Get provider name
     *
     * @return string Provider name
     */
    public function get_provider_name() {
        return 'Twilio';
    }

    /**
     * Validate provider configuration
     *
     * @return array Response array with 'success' and 'message' or 'error'
     */
    public function validate_configuration() {
        $account_sid = get_option('twp_account_sid');
        $auth_token = get_option('twp_auth_token');
        $from_number = get_option('twp_sms_from_number');

        if (empty($account_sid)) {
            return [
                'success' => false,
                'error' => 'Twilio Account SID is not configured'
            ];
        }

        if (empty($auth_token)) {
            return [
                'success' => false,
                'error' => 'Twilio Auth Token is not configured'
            ];
        }

        if (empty($from_number)) {
            return [
                'success' => false,
                'error' => 'SMS from number is not configured'
            ];
        }

        if (!$this->client) {
            return [
                'success' => false,
                'error' => 'Failed to initialize Twilio client'
            ];
        }

        return [
            'success' => true,
            'message' => 'Twilio SMS provider is properly configured'
        ];
    }
}