<?php
/**
 * The connect sequence.
 *
 * @package CortexCommerce
 */

namespace CortexCommerce\Connect;

use CortexCommerce\Settings\Config;
use CortexCommerce\Settings\Options;
use CortexCommerce\Support\Log;
use CortexCommerce\Sync\ProductSync;
use CortexCommerce\Sync\SyncSchedule;

defined( 'ABSPATH' ) || exit;

/**
 * Spec §4.1 step 4: checks, lock, mint, /complete, store, schedule the product sync. Any failure after minting
 * revokes the key. The key's id is stored as pending before the key leaves the store, so KeyScope limits it from its
 * first use, and a process that dies during /complete leaves an id the next attempt (or deactivation) can revoke.
 *
 * Both calls that follow a side effect (the backend /complete call, and scheduling the sync) catch \Throwable
 * rather than only ConnectException: a client implementation is not guaranteed to only ever throw
 * ConnectException. Whatever goes wrong after the key is minted must never leave an orphan key, and whatever goes
 * wrong after the connection is saved must never lose that connection.
 *
 * Since 1.1.0 connecting no longer registers WooCommerce product webhooks: the plugin pushes the catalog itself
 * (contract §5c).
 */
final class ConnectFlow {

	/**
	 * @var KeyMinter
	 */
	private $minter;

	/**
	 * @var ConnectClient
	 */
	private $client;

	public function __construct( ?KeyMinter $minter = null, ?ConnectClient $client = null ) {
		$this->minter = $minter ?? new KeyMinter();
		$this->client = $client ?? new ConnectClient();
	}

	/**
	 * @return string 'connected', 'busy', or a failure reason.
	 */
	public function connect( string $code, int $user_id ): string {
		$code = trim( $code );
		if ( 1 !== preg_match( '/^[A-Za-z0-9_-]{16,128}$/', $code ) ) {
			return $this->fail( 'invalid_code_format' );
		}
		$blocker = Config::connect_blocker();
		if ( null !== $blocker ) {
			// Not stored as last_error: the live blocker notice on the connect screen already says it, and a
			// stored copy would outlive the merchant fixing the setting.
			return $blocker;
		}
		if ( Options::is_connected() ) {
			return $this->fail( 'already_connected' );
		}
		if ( ! Options::acquire_connect_lock() ) {
			return 'busy';
		}

		try {
			// Re-checked under the lock: an attempt that held the lock may have connected since the check above,
			// and minting now would overwrite that connection and orphan its live key.
			if ( Options::is_connected() ) {
				return $this->fail( 'already_connected' );
			}

			$this->minter->revoke_pending();
			try {
				$key = $this->minter->mint( $user_id );
			} catch ( ConnectException $e ) {
				Log::error( 'Connect failed: ' . $e->getMessage() );
				return $this->fail( $e->reason() );
			}

			Options::save_pending_key_id( $key['key_id'] );

			try {
				$reply = $this->client->complete( $code, $key );
			} catch ( \Throwable $e ) {
				$this->minter->revoke_pending();
				$reason = $e instanceof ConnectException ? $e->reason() : 'unreachable';
				Log::warning( 'Connect failed, key revoked: ' . $e->getMessage() );
				return $this->fail( $reason );
			}

			Options::save_connection( $reply['tenant_id'], $key['key_id'], $reply['webhook_secret'], $reply['pixel_id'] );
			Options::clear_pending_key_id();
			Options::reset_settings_for_new_connection();
			Options::clear_last_error();
			Log::info( 'Connected as ' . $reply['tenant_id'] );

			// Each in its own try: a throw scheduling one must not leave the store without the other.
			try {
				ProductSync::schedule();
			} catch ( \Throwable $e ) {
				Log::error( 'Connected, but scheduling the product sync failed: ' . $e->getMessage() );
			}
			try {
				SyncSchedule::schedule();
			} catch ( \Throwable $e ) {
				Log::error( 'Connected, but scheduling the hourly approved-product sync failed: ' . $e->getMessage() );
			}
			return 'connected';
		} finally {
			Options::release_connect_lock();
		}
	}

	private function fail( string $reason ): string {
		Options::set_last_error( $reason, Messages::for_reason( $reason ) );
		return $reason;
	}
}