SimpleDebugger.php

<?php

class Debugger {
    private $transaction_id;
    private $debug;

    function __construct(bool $debug = false)
    {
        $this->transaction_id = 1;
        $this->debug = $debug;
    }

    public function run(int $port = 9000) {
        $socket = stream_socket_server("tcp://0.0.0.0:${port}", $errno, $errstr);
        if (!$socket) {
            echo "${errstr} (${errno})\n";
            die('Could not create socket');
        }

        while (true) {
            while ($conn = stream_socket_accept($socket, -1)) {
                $this->getMessage($conn); // get initial
                $this->sendCommand($conn, "stdout");
                $this->getMessage($conn); // get strem
                $this->sendCommand($conn, "step");

                while(true) {
                    $message = $this->getMessage($conn);
                    $response = $this->getResponse($message);
                    if (isset($response['status']) && $response['status'] == 'stopping') {
                        break;
                    }
                    $this->handleResponse($response);
                    if ($response['_type'] === 'stream') {
                        continue;
                    }
                    $input = readline(">> ");
                    if ($input == "exit") {
                        break;
                    }
                    $this->sendCommand($conn, $input);
                }
                fclose($conn);
            }
        }

        fclose($socket);
    }

    private function getMessage($conn) {
        $message = "";
        while (true) {
            $chunk = stream_socket_recvfrom($conn, 1024, 0);
            $message .= $chunk;
            $len = strlen($message);
            if ($message[$len - 1] == "\0") {
                break;
            }
        }
        if ($this->debug) {
            echo $message;
        }
        return $message;
    }

    private function getResponse(string $message) {
        preg_match('/^(\d+)\0([\s\S]+)/', $message, $matches);
        $dom = DOMDocument::loadXML($matches[2]);
        $init = $dom->getElementsByTagName("init");
        if ($init->length != 0) {
            $obj = ["_type" => "init"];
            foreach ($init[0]->attributes as $attribute) {
                $obj[$attribute->name] = $attribute->value;
            }
            return $obj;
        }
        $stream = $dom->getElementsByTagName('stream');
        if ($stream->length != 0) {
            $obj = ['_type' => 'stream'];
            foreach ($stream[0]->attributes as $attribute) {
                $obj[$attribute->name] = $attribute->value;
            }
            if (isset($obj['encoding']) && $obj['encoding'] === 'base64') {
                $obj['body'] = base64_decode($stream[0]->nodeValue);
            } else {
                $obj['body'] = $obj->nodeValue;
            }
            return $obj;
        }
        $response = $dom->getElementsByTagName("response");
        $obj = ["_type" => "response"];
        foreach ($response[0]->attributes as $attribute) {
            $obj[$attribute->name] = $attribute->value;
        }
        if ($obj['command'] == 'eval') {
            $properties = [];
            $property = $dom->getElementsByTagName("property");
            if ($property->length != 0) {
                foreach ($property[0]->attributes as $attribute) {
                    $properties[$attribute->name] = $attribute->value;
                }
                if (isset($properties['encoding']) && $properties['encoding'] === 'base64') {
                    $properties['body'] = base64_decode($property[0]->nodeValue);
                } else if ($properties['type'] === 'object') {
                    $properties['body'] = "<".$properties['classname'].">";
                } else {
                    $properties['body'] = $property[0]->nodeValue;
                }
                $obj["property"] = $properties;
            }
        } else {
            $debugMessages = [];
            $messages = $dom->getElementsByTagName("message");
            if ($messages->length !== 0) {
                foreach ($messages[0]->attributes as $attribute) {
                    $debugMessages[$attribute->name] = $attribute->value;
                }
                $obj["xdebug:message"] = $debugMessages;
            }
        }
        return $obj;
    }

    private function handleResponse(array $obj) {
        switch($obj["_type"]){
            case 'init':
                // $file = $obj['fileuri'];
                // $lineno = $obj['lineno'];
                return;
            case 'stream':
                echo $obj['body'] . PHP_EOL;
                break;
            case 'response':
                if (isset($obj['property'])) {
                    echo $obj['property']['body'] . PHP_EOL;
                }
                if (isset($obj['xdebug:message'])) {
                    $file = $obj['xdebug:message']['filename'];
                    $lineno = $obj['xdebug:message']['lineno'];
                    break;
                }
        }
        if (isset($file) && $file != "" && $file != NULL) {
            echo "$file at $lineno\n";
            $this->showFile($file, (int)$lineno);
        }
    }

    private function showFile(string $file, int $lineno) {
        $fp = fopen($file, 'r');
        $size = 15;
        $cnt = $lineno < 7 ? 0 : $lineno - 7;
        $current = 1;
        while ($cnt > 0) {
            fgets($fp);
            $cnt--;
            $current++;
        }
        while ($line = fgets($fp)) {
            if ($current == $lineno) {
                echo ">> $line";
            } else {
                echo "   $line";
            }
            $size--;
            $current++;
            if ($size == 0) {
                break;
            }
        }
        fclose($fp);
    }

    private function sendCommand($conn, string $input) {
        if (in_array($input, ["n", "next"])) {
            $command = "step_over -i $this->transaction_id";
        } else if (in_array($input, ["c", "continue"])) {
            $command = "run -i $$this->transaction_id";
        } else if (in_array($input, ["s", "step"])) {
            $command = "step_into -i $$this->transaction_id";
        } else if (in_array($input, ["status"])) {
            $command = "status -i $$this->transaction_id";
        } else if (in_array($input, ["source"])) {
            $command = "source -i $$this->transaction_id";
        } else if (in_array($input, ["stdout"])) {
            $command = "stdout -i $$this->transaction_id -c 1";
        } else if (in_array($input, ["w", "whereami"])) {
            return;
        } else {
            $b64encoded = base64_encode($input);
            $command = "eval -i $$this->transaction_id -- ${b64encoded}";
        }

        stream_socket_sendto($conn, "${command}\0");

        $this->transaction_id++;
    }

}

$options = getopt('d');
$debugger = new Debugger(isset($options['d']));
$debugger->run();