# HG changeset patch
# User paulsnar <paulsnar@paulsnar.lv>
# Date 1673702792 -7200
#      Sat Jan 14 15:26:32 2023 +0200
# Node ID b666db0c64dd7dc510ce4841dbaf18d72a04a719
# Parent  3806547c3601147cf82b4c4db3fac2175ea25dac
fix: more graceful behavior on connection closure/failure

diff --git a/src/Connection.php b/src/Connection.php
--- a/src/Connection.php
+++ b/src/Connection.php
@@ -14,6 +14,9 @@
     protected string $_lastLine;
     protected Set $watching;
 
+    /**
+     * @throws Exceptions\ConnectionClosed on failure to connect
+     */
     public function __construct(
         string $host = '::1',
         int $port = 11300,
@@ -29,7 +32,7 @@
             $timeout,
         );
         if ($this->connection === false) {
-            throw new \RuntimeException("Failed to connect: {$errstr}", $errno);
+            throw new Exceptions\ConnectionClosed("Failed to connect: {$errstr}", $errno);
         }
 
         stream_set_timeout($this->connection, $timeout);
@@ -44,11 +47,23 @@
 
     public function __destruct()
     {
-        fclose($this->connection);
+        $this->close();
+    }
+
+    public function close(): void
+    {
+        if ($this->connection !== null) {
+            fclose($this->connection);
+            $this->connection = null;
+        }
     }
 
     protected function _write(string ...$args): void
     {
+        if ($this->connection === null) {
+            throw new Exceptions\ConnectionClosed();
+        }
+
         $line = implode(" ", $args);
         fwrite($this->connection, "{$line}\r\n");
     }
@@ -66,10 +81,15 @@
      */
     protected function _read(int $timeout = self::DEFAULT_CONNECTION_TIMEOUT): array
     {
+        if ($this->connection === null) {
+            throw new Exceptions\ConnectionClosed();
+        }
+
         stream_set_timeout($this->connection, $timeout);
         $line = fgets($this->connection);
         if ($line === false) {
             if (feof($this->connection)) {
+                $this->close();
                 throw new Exceptions\ConnectionClosed();
             } else {
                 throw new Exceptions\ConnectionTimeout();
@@ -133,6 +153,7 @@
 
     /**
      * @throws Exceptions\Buried
+     * @throws Exceptions\ConnectionClosed
      * @throws Exceptions\Draining
      * @throws Exceptions\JobTooBig
      * @throws Exceptions\ProtocolError
@@ -151,6 +172,7 @@
             (string) $timeToRun,
             (string) strlen($body),
         );
+        // Assume that $this->connection !== null if the above doesn't fail.
         fwrite($this->connection, $body);
         fwrite($this->connection, "\r\n");
         fflush($this->connection);