<?php

namespace Alexr\Voice;

use Alexr\Whatsapp\DTO\SendMessageRequest;
use Alexr\Whatsapp\WhatsappManager;
use Alexr\Whatsapp\WhatsappProviderFactory;

/**
 * Class WhatsappVoiceRedirection
 *
 * Handles incoming Twilio voice call webhooks.
 *
 * When someone calls the restaurant's Twilio phone number:
 *   1. Twilio hits this webhook (POST)
 *   2. We respond with TwiML: read a message in Spanish using <Say>
 *   3. We send a WhatsApp message to the caller's number
 *
 * Register your Twilio phone number's "A call comes in" webhook URL to:
 *   https://yoursite.com/wp-admin/admin-ajax.php?action=alexr_whatsapp_voice&restaurant_id=1
 *
 * @package Alexr\Whatsapp
 */
class TwilioVoiceRedirection
{
	/**
	 * The TwiML message read aloud to the caller (Spanish).
	 * Override via filter: alexr_whatsapp_voice_message
	 */
	protected const DEFAULT_VOICE_MESSAGE =
		'Hola, gracias por llamar. En este momento no podemos atender su llamada. ' .
		'Le enviaremos un mensaje de WhatsApp a su número para que podamos ayudarle. ' .
		'Hasta pronto.';

	/**
	 * The WhatsApp message sent after the call.
	 * Override via filter: alexr_whatsapp_voice_whatsapp_message
	 */
	protected const DEFAULT_WHATSAPP_MESSAGE =
		'👋 Hola, ha llamado al restaurante y no hemos podido atenderle. ' .
		'¿En qué podemos ayudarle? Responda a este mensaje y le atenderemos encantados.';

	/**
	 * Register WordPress AJAX endpoints.
	 */
	public static function register(): void
	{
		add_action('wp_ajax_nopriv_alexr_whatsapp_voice', [self::class, 'handleVoiceCall']);
		add_action('wp_ajax_alexr_whatsapp_voice', [self::class, 'handleVoiceCall']);
	}

	/**
	 * Main handler: called by Twilio when a voice call comes in.
	 *
	 * Twilio sends (among others) these POST params:
	 *   - From:   caller's phone number (e.g. +34612345678)
	 *   - To:     restaurant's Twilio number
	 *   - CallSid, Direction, CallStatus, etc.
	 */
	public static function handleVoiceCall(): void
	{
		$payload = self::getPayload();

		ray($payload);

		// Log for debugging
		self::logVoiceCall($payload);

		$callerPhone = self::extractCallerPhone($payload);
		$restaurantId = self::getRestaurantId($payload);

		// Send WhatsApp message to caller (best-effort, non-blocking)
		if ($callerPhone && $restaurantId) {
			ray('Enviar whatsapp al cliente: ' . $callerPhone . ' - ' . $restaurantId . ' -');
			//self::sendWhatsAppToCall($callerPhone, $restaurantId, $payload);
		}

		// Always respond with TwiML so Twilio reads the message and hangs up
		self::respondWithTwiml($restaurantId);
	}

	// -------------------------------------------------------------------------
	// Private helpers
	// -------------------------------------------------------------------------

	/**
	 * Extract the caller's E.164 phone number from the Twilio payload.
	 */
	protected static function extractCallerPhone(array $payload): ?string
	{
		$from = $payload['From'] ?? '';

		// Remove any whatsapp: prefix just in case
		$from = str_replace('whatsapp:', '', $from);

		// Must start with + to be a valid E.164 number
		if (empty($from) || $from[0] !== '+') {
			return null;
		}

		return $from;
	}

	/**
	 * Determine the restaurant ID from the request.
	 * Tries query-string first, then matches by 'To' phone number.
	 */
	protected static function getRestaurantId(array $payload): ?int
	{
		// 1. From query string (?restaurant_id=X)
		if (!empty($_GET['restaurant_id'])) {
			return (int) $_GET['restaurant_id'];
		}

		// 2. Match by 'To' phone number (the Twilio number that was called)
		$toPhone = $payload['To'] ?? '';
		$toPhone = str_replace('whatsapp:', '', $toPhone);

		if ($toPhone) {
			$restaurantId = WhatsappProviderFactory::findRestaurantByPhone($toPhone);
			if ($restaurantId) {
				return $restaurantId;
			}
		}

		// 3. WordPress filter fallback
		$default = apply_filters('alexr_whatsapp_default_restaurant_id', null);
		if ($default) {
			return (int) $default;
		}

		return null;
	}

	/**
	 * Send a WhatsApp message to the person who called.
	 */
	protected static function sendWhatsAppToCall(
		string $callerPhone,
		int $restaurantId,
		array $payload
	): void {
		try {
			$manager = WhatsappManager::forRestaurant($restaurantId);

			if (! $manager->getProvider() || ! $manager->getProvider()->isConfigured()) {
				self::logError('Provider not configured for restaurant ' . $restaurantId);
				return;
			}

			$whatsappMessage = apply_filters(
				'alexr_whatsapp_voice_whatsapp_message',
				self::DEFAULT_WHATSAPP_MESSAGE,
				$callerPhone,
				$restaurantId,
				$payload
			);

			$request          = new SendMessageRequest();
			$request->toPhone = $callerPhone;
			$request->body    = $whatsappMessage;

			$result = $manager->sendMessage($request);

			if (function_exists('ray')) {
				ray('WhatsApp Voice Redirection - WA sent', [
					'to'     => $callerPhone,
					'result' => $result,
				])->green();
			}

			do_action('alexr_whatsapp_voice_wa_sent', $callerPhone, $restaurantId, $result, $payload);

		} catch (\Throwable $e) {
			self::logError('Failed to send WhatsApp after call: ' . $e->getMessage(), [
				'caller' => $callerPhone,
				'restaurant_id' => $restaurantId,
			]);
		}
	}

	/**
	 * Output TwiML response that reads a Spanish message and hangs up.
	 *
	 * TwiML reference:
	 *   <Say language="es-ES" voice="Polly.Conchita"> reads text in Spanish.
	 *   <Hangup> ends the call cleanly.
	 */
	protected static function respondWithTwiml(?int $restaurantId): void
	{
		$voiceMessage = apply_filters(
			'alexr_whatsapp_voice_message',
			self::DEFAULT_VOICE_MESSAGE,
			$restaurantId
		);

		// Sanitize to avoid breaking the XML
		$voiceMessage = htmlspecialchars($voiceMessage, ENT_XML1, 'UTF-8');

		$twiml = <<<XML
<?xml version="1.0" encoding="UTF-8"?>
<Response>
    <Say language="es-ES" voice="Polly.Conchita">{$voiceMessage}</Say>
    <Hangup/>
</Response>
XML;

		header('Content-Type: text/xml; charset=UTF-8');
		echo $twiml;
		wp_die();
	}

	/**
	 * Get the POST payload sent by Twilio.
	 */
	protected static function getPayload(): array
	{
		return $_POST ?: [];
	}

	/**
	 * Log the incoming voice call (only when debug is enabled).
	 */
	protected static function logVoiceCall(array $payload): void
	{
		if (! defined('ALEXR_WHATSAPP_DEBUG') || ! ALEXR_WHATSAPP_DEBUG) {
			return;
		}

		$logData = [
			'type'      => 'voice_call',
			'from'      => $payload['From'] ?? null,
			'to'        => $payload['To'] ?? null,
			'call_sid'  => $payload['CallSid'] ?? null,
			'status'    => $payload['CallStatus'] ?? null,
			'timestamp' => current_time('mysql'),
		];

		if (function_exists('ray')) {
			ray('WhatsApp Voice Redirection', $logData);
		}

		do_action('alexr_whatsapp_voice_log', $logData);
	}

	/**
	 * Log an error.
	 */
	protected static function logError(string $message, array $context = []): void
	{
		$logData = array_merge(['error' => $message], $context);

		if (function_exists('ray')) {
			ray('WhatsApp Voice Redirection ERROR', $logData);
		}

		error_log('[WhatsApp Voice Redirection] ' . json_encode($logData));
		do_action('alexr_whatsapp_voice_error', $logData);
	}
}

// Register the AJAX endpoints automatically when this file is loaded
WhatsappVoiceRedirection::register();