<?php

namespace Alexr\Whatsapp;

use Alexr\Models\WhatsappMessage;
use Alexr\Whatsapp\Providers\Dialog360Provider;

/**
 * Class WhatsappWebhookController
 *
 * Handles WordPress AJAX endpoints for WhatsApp webhooks.
 * Provider-agnostic - works with any registered provider.
 *
 * @package Alexr\Whatsapp
 */
class WhatsappWebhookController
{
	/**
	 * Register webhook endpoints
	 */
	public static function register(): void
	{
		//ray('REGISTER WEBHOOKS');

		// Incoming messages webhook (public, no auth required)
		add_action('wp_ajax_nopriv_alexr_whatsapp_webhook', [self::class, 'handleIncomingWebhook']);
		add_action('wp_ajax_alexr_whatsapp_webhook', [self::class, 'handleIncomingWebhook']);

		// Status callback webhook (public, no auth required)
		add_action('wp_ajax_nopriv_alexr_whatsapp_status_callback', [self::class, 'handleStatusCallback']);
		add_action('wp_ajax_alexr_whatsapp_status_callback', [self::class, 'handleStatusCallback']);
	}

	/**
	 * Handle incoming message webhook
	 */
	public static function handleIncomingWebhook(): void
	{
		// Handle 360dialog webhook verification (GET request)
		if ($_SERVER['REQUEST_METHOD'] === 'GET') {
			self::handleWebhookVerification();
			return;
		}

		// Get restaurant ID
		$restaurantId = self::getRestaurantId();
		//ray('restaurantId: ' . $restaurantId);

		if (!$restaurantId) {
			self::logWebhookError('incoming', 'Restaurant not found', $_POST);
			self::respondWithError('Restaurant not found', 404);
			return;
		}

		// Get the manager (which auto-detects provider)
		$manager = WhatsappManager::forRestaurant($restaurantId);

		if (!$manager->getProvider()) {
			self::logWebhookError('incoming', 'No provider configured', $_POST, $restaurantId);
			self::respondWithError('No provider configured', 500);
			return;
		}

		// Get the raw payload
		$payload = self::getPayload();

		// Validate signature if enabled
		if (self::shouldValidateSignature()) {
			$signature = self::getSignatureHeader();
			$url = self::getCurrentUrl();

			if (!$manager->validateWebhookSignature($signature, $url, $payload)) {
				self::logWebhookError('incoming', 'Invalid signature', $payload, $restaurantId);
				self::respondWithError('Invalid signature', 403);
				return;
			}
		}

		// Process the webhook
		$result = $manager->processWebhook($payload);

		// Log for debugging
		self::logWebhook('incoming', $payload, $result, $restaurantId);

		// Generate response
		$response = apply_filters('alexr_whatsapp_webhook_response', null, $result, $restaurantId);

		header('Content-Type: ' . $manager->getWebhookResponseContentType());
		echo $manager->generateWebhookResponse($response);
		wp_die();
	}

	/**
	 * Handle status callback webhook
	 */
	public static function handleStatusCallback(): void
	{
		$restaurantId = self::getRestaurantId();

		// For status callbacks, try to find restaurant from the message if not in URL
		if (!$restaurantId) {
			$payload = self::getPayload();
			$messageSid = $payload['MessageSid'] ?? null;

			// Also check Cloud API format
			if (!$messageSid) {
				$entry = $payload['entry'][0] ?? [];
				$changes = $entry['changes'][0] ?? [];
				$value = $changes['value'] ?? [];
				$statuses = $value['statuses'][0] ?? [];
				$messageSid = $statuses['id'] ?? null;
			}

			if ($messageSid) {
				$message = WhatsappMessage::findBySid($messageSid);
				if ($message) {
					$restaurantId = $message->restaurant_id;
				}
			}
		}

		if (!$restaurantId) {
			self::logWebhookError('status', 'Restaurant not found', $_POST);
			self::respondWithError('Restaurant not found', 404);
			return;
		}

		$manager = WhatsappManager::forRestaurant($restaurantId);

		if (!$manager->getProvider()) {
			self::logWebhookError('status', 'No provider configured', $_POST, $restaurantId);
			self::respondWithError('No provider configured', 500);
			return;
		}

		$payload = self::getPayload();

		// Validate signature
		if (self::shouldValidateSignature()) {
			$signature = self::getSignatureHeader();
			$url = self::getCurrentUrl();

			if (!$manager->validateWebhookSignature($signature, $url, $payload)) {
				self::logWebhookError('status', 'Invalid signature', $payload, $restaurantId);
				self::respondWithError('Invalid signature', 403);
				return;
			}
		}

		// Process status callback
		$result = $manager->processWebhook($payload);

		// Log for debugging
		self::logWebhook('status', $payload, $result, $restaurantId);

		// Respond with appropriate content type
		header('Content-Type: ' . $manager->getWebhookResponseContentType());
		echo $manager->generateWebhookResponse();
		wp_die();
	}

	/**
	 * Handle webhook verification (for 360dialog/Cloud API)
	 */
	protected static function handleWebhookVerification(): void
	{
		$restaurantId = self::getRestaurantId();

		if (!$restaurantId) {
			// Try to find by hub.verify_token or default
			$restaurantId = apply_filters('alexr_whatsapp_default_restaurant_id', null);
		}

		if (!$restaurantId) {
			status_header(404);
			echo 'Restaurant not found';
			wp_die();
		}

		$manager = WhatsappManager::forRestaurant($restaurantId);
		$provider = $manager->getProvider();

		// Only 360dialog needs verification handling
		if ($provider instanceof Dialog360Provider) {
			$challenge = $provider->handleWebhookVerification($_GET);

			if ($challenge !== null) {
				status_header(200);
				echo $challenge;
				wp_die();
			}
		}

		status_header(403);
		echo 'Verification failed';
		wp_die();
	}

	/**
	 * Get the webhook payload
	 *
	 * @return array
	 */
	protected static function getPayload(): array
	{
		// First try to get JSON body (for 360dialog/Cloud API)
		$rawBody = file_get_contents('php://input');

		if ($rawBody) {
			$jsonPayload = json_decode($rawBody, true);
			if (is_array($jsonPayload)) {
				return $jsonPayload;
			}
		}

		// Fall back to $_POST (for Twilio)
		return $_POST;
	}

	/**
	 * Get signature header (handles different provider formats)
	 *
	 * @return string
	 */
	protected static function getSignatureHeader(): string
	{
		// Twilio uses X-Twilio-Signature
		if (!empty($_SERVER['HTTP_X_TWILIO_SIGNATURE'])) {
			return $_SERVER['HTTP_X_TWILIO_SIGNATURE'];
		}

		// 360dialog/Cloud API uses X-Hub-Signature-256
		if (!empty($_SERVER['HTTP_X_HUB_SIGNATURE_256'])) {
			return $_SERVER['HTTP_X_HUB_SIGNATURE_256'];
		}

		// Also check lowercase versions
		if (!empty($_SERVER['HTTP_X_HUB_SIGNATURE'])) {
			return $_SERVER['HTTP_X_HUB_SIGNATURE'];
		}

		return '';
	}

	/**
	 * Get restaurant ID from request
	 *
	 * @return int|null
	 */
	protected static function getRestaurantId(): ?int
	{
		// First, try from query string
		if (!empty($_GET['restaurant_id'])) {
			return (int)$_GET['restaurant_id'];
		}

		// Second, try to determine from the 'To' phone number (Twilio format)
		// For inbound messages, 'To' is the restaurant's number
		$toPhone = $_POST['To'] ?? '';
		$toPhone = str_replace('whatsapp:', '', $toPhone);

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

		// Third, try 'From' phone number (Twilio format)
		// For outbound status callbacks, 'From' is the restaurant's number
		$fromPhone = $_POST['From'] ?? '';
		$fromPhone = str_replace('whatsapp:', '', $fromPhone);

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

		// Fourth, try Cloud API format (360dialog)
		$payload = self::getPayload();
		$entry = $payload['entry'][0] ?? [];
		$changes = $entry['changes'][0] ?? [];
		$value = $changes['value'] ?? [];
		$metadata = $value['metadata'] ?? [];
		$displayPhone = $metadata['display_phone_number'] ?? '';

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

		// Fifth, use default restaurant filter
		$defaultRestaurant = apply_filters('alexr_whatsapp_default_restaurant_id', null);
		if ($defaultRestaurant) {
			return (int)$defaultRestaurant;
		}

		return null;
	}

	/**
	 * Check if we should validate webhook signature
	 *
	 * @return bool
	 */
	protected static function shouldValidateSignature(): bool
	{
		// Disable in development/sandbox mode
		if (defined('ALEXR_WHATSAPP_SKIP_SIGNATURE') && ALEXR_WHATSAPP_SKIP_SIGNATURE) {
			return false;
		}

		// Can be filtered
		return apply_filters('alexr_whatsapp_validate_signature', true);
	}

	/**
	 * Get current request URL
	 *
	 * @return string
	 */
	protected static function getCurrentUrl(): string
	{
		$protocol = is_ssl() ? 'https://' : 'http://';
		return $protocol . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];
	}

	/**
	 * Respond with error
	 *
	 * @param string $message
	 * @param int $statusCode
	 */
	protected static function respondWithError(string $message, int $statusCode = 400): void
	{
		status_header($statusCode);

		// Try to determine provider for response format
		$restaurantId = self::getRestaurantId();
		if ($restaurantId) {
			$manager = WhatsappManager::forRestaurant($restaurantId);
			header('Content-Type: ' . $manager->getWebhookResponseContentType());
			echo $manager->generateWebhookResponse();
		} else {
			// Default to XML (Twilio format)
			header('Content-Type: text/xml');
			echo '<?xml version="1.0" encoding="UTF-8"?><Response></Response>';
		}

		wp_die();
	}

	/**
	 * Log webhook for debugging
	 *
	 * @param string $type
	 * @param array $payload
	 * @param array $result
	 * @param int $restaurantId
	 */
	protected static function logWebhook(string $type, array $payload, array $result, int $restaurantId): void
	{
		// Only log if debugging is enabled
		if (!defined('ALEXR_WHATSAPP_DEBUG') || !ALEXR_WHATSAPP_DEBUG) {
			return;
		}

		$manager = WhatsappManager::forRestaurant($restaurantId);

		$logData = [
			'type' => $type,
			'provider' => $manager->getProviderName(),
			'restaurant_id' => $restaurantId,
			'payload' => $payload,
			'result' => $result,
			'timestamp' => current_time('mysql'),
		];

		// Use Ray if available (for development)
		if (function_exists('ray')) {
			ray('WhatsApp Webhook', $logData)->blue();
		}

		// Fire action for custom logging
		do_action('alexr_whatsapp_webhook_log', $logData);

		// Optionally log to file
		if (defined('ALEXR_WHATSAPP_LOG_FILE') && ALEXR_WHATSAPP_LOG_FILE) {
			error_log(
				'[WhatsApp Webhook] ' . json_encode($logData) . PHP_EOL,
				3,
				ALEXR_WHATSAPP_LOG_FILE
			);
		}
	}

	/**
	 * Log webhook error
	 *
	 * @param string $type
	 * @param string $error
	 * @param array $payload
	 * @param int|null $restaurantId
	 */
	protected static function logWebhookError(string $type, string $error, array $payload, ?int $restaurantId = null): void
	{
		$provider = null;
		if ($restaurantId) {
			$manager = WhatsappManager::forRestaurant($restaurantId);
			$provider = $manager->getProviderName();
		}

		$logData = [
			'type' => $type,
			'error' => $error,
			'provider' => $provider,
			'restaurant_id' => $restaurantId,
			'payload' => $payload,
			'timestamp' => current_time('mysql'),
		];

		// Always log errors
		if (function_exists('ray')) {
			ray('WhatsApp Webhook Error', $logData)->red();
		}

		// Fire action for custom error handling
		do_action('alexr_whatsapp_webhook_error', $logData);

		// Log to error log
		error_log('[WhatsApp Webhook Error] ' . json_encode($logData));
	}
}

// Register the controller
WhatsappWebhookController::register();