<?php

namespace Kicken\Chat;


class HTTPClient extends StreamSocketClient implements IHTTPRouter {
    private $mHeaders = '';
    private $mRequestBody = '';
    private $mGotHeaders = false;
    private $mCloseAfterWrite = false;

    public function __construct($resource){
        parent::__construct($resource);
    }

    public function nowReadable(){
        parent::nowReadable();

        $this->dataAvailable();
    }

    public function dataAvailable(){
        if (!$this->mGotHeaders){
            $data = $this->readAll();
            $pos = strpos($data, "\r\n\r\n");
            if (false !== $pos){
                $this->mGotHeaders = true;
                $pos += 4;
                $this->mHeaders .= substr($data, 0, $pos);
                $this->mRequestBody .= substr($data, $pos);

                if ($this->processHeaders()){
                    $this->doRouting();
                }
            } else {
                $this->mHeaders .= $data;
            }
        } else {
            $this->mRequestBody .= $this->readAll();
            $this->doRouting();
        }
    }

    private function doRouting(){
        try {
            $this->route($this->mHeaders['REQUEST_URI']);
        } catch (\Exception $e){
            $this->sendResponse(500, $e->getMessage());
        }
    }

    protected function processHeaders(){
        $curHeader = [];
        $allHeaders = [];
        $headers = rtrim($this->mHeaders);

        foreach (explode("\r\n", $headers) as $l){
            if (preg_match('#^([a-z]+)\s+(.*)\s+HTTP/1.[01]$#i', $l, $matches)){
                if (strpos($matches[2], '?') !== false){
                    list($uri, $qs) = explode('?', $matches[2]);
                } else {
                    $uri = $matches[2];
                    $qs = '';
                }

                $allHeaders[] = [
                    'REQUEST_METHOD',
                    $matches[1]
                ];
                $allHeaders[] = [
                    'REQUEST_URI',
                    $uri
                ];
                $allHeaders[] = [
                    'QUERY_STRING',
                    $qs
                ];
            } else if ($l[0] == ' ' || $l[0] == "\t"){
                $curHeader[1] .= ltrim($l);
            } else {
                if ($curHeader){
                    $allHeaders[] = $curHeader;
                }

                $curHeader = explode(':', $l, 2);
                $curHeader[0] = rtrim($curHeader[0]);
                $curHeader[1] = ltrim($curHeader[1]);
            }
        }
        if ($curHeader){
            $allHeaders[] = $curHeader;
        }

        $this->mHeaders = [];
        foreach ($allHeaders as $h){
            $h[0] = strtoupper($h[0]);
            $h[0] = str_replace('-', '_', $h[0]);
            $this->mHeaders[$h[0]] = $h[1];
        }

        return isset($this->mHeaders['REQUEST_METHOD']) && isset($this->mHeaders['REQUEST_URI']);
    }

    protected function getCodeText($code){
        switch ($code){
            case '200':
                return 'Ok';
            case '400':
                return 'Bad Request';
            case '404':
                return 'Not Found';
            case '403':
                return 'Forbidden';
            case '405':
                return 'Method not allowed';
            case '415':
                return 'Unsupported media type';
            case '500':
                return 'Internal Server Error';
        }

        return 'Unknown';
    }

    protected function sendResponse($code, $body = null, $headers = []){
        $response = sprintf("HTTP/1.0 %d %s\r\n", $code, $this->getCodeText($code));
        $defaultHeaders = [
            'EXPIRES' => gmdate(DATE_RFC1123),
            'PRAGMA' => 'no-cache',
            'CACHE_CONTROL' => 'no-cache',
            'LAST_MODIFIED' => gmdate(DATE_RFC1123),
            'DATE' => gmdate(DATE_RFC1123),
            'SERVER' => 'phpchatd',
            'CONTENT_LENGTH' => strlen($body),
            'CONTENT_TYPE' => 'text/html'
        ];

        $headers = array_merge($defaultHeaders, $headers);

        foreach ($headers as $h => $vlist){
            if ($vlist !== null){
                $h = ucfirst(strtolower($h));
                $h = str_replace('_', '-', $h);

                foreach ((array)$vlist as $v){
                    $response .= "{$h}: {$v}\r\n";
                }
            }
        }

        $response .= "\r\n";
        $response .= $body;

        $this->mCloseAfterWrite = true;
        $this->writeSocket($response);
    }

    public function writeSocket($data){
        parent::writeSocket($data);
        if ($this->mCloseAfterWrite && !$this->hasPendingWrites()){
            $this->close();
        }
    }

    public function route($uri){
        $this->sendResponse(404);
    }

    protected function getRequestHeaders(){
        return $this->mHeaders;
    }

    protected function getRequestBody(){
        return $this->mRequestBody;
    }

    protected function getQueryVars(){
        parse_str($this->mHeaders['QUERY_STRING'], $GET);

        return $GET;
    }
}