// miniwebserver.cpp

/**
*    Copyright (C) 2008 10gen Inc.
*
*    This program is free software: you can redistribute it and/or  modify
*    it under the terms of the GNU Affero General Public License, version 3,
*    as published by the Free Software Foundation.
*
*    This program is distributed in the hope that it will be useful,
*    but WITHOUT ANY WARRANTY; without even the implied warranty of
*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
*    GNU Affero General Public License for more details.
*
*    You should have received a copy of the GNU Affero General Public License
*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/


#include "stdafx.h"
#include "miniwebserver.h"

MiniWebServer::MiniWebServer() {
    sock = 0;
}

bool MiniWebServer::init(int port) {
    SockAddr me(port);
    sock = socket(AF_INET, SOCK_STREAM, 0);
    if ( sock == INVALID_SOCKET ) {
        log() << "ERROR: MiniWebServer listen(): invalid socket? " << errno << endl;
        return false;
    }
    prebindOptions( sock );
    if ( ::bind(sock, (sockaddr *) &me.sa, me.addressSize) != 0 ) {
        log() << "MiniWebServer: bind() failed port:" << port << " errno:" << errno << endl;
        if ( errno == 98 )
            log() << "98 == addr already in use" << endl;
        closesocket(sock);
        return false;
    }

    if ( ::listen(sock, 16) != 0 ) {
        log() << "MiniWebServer: listen() failed " << errno << endl;
        closesocket(sock);
        return false;
    }

    return true;
}

string MiniWebServer::parseURL( const char * buf ){
    const char * urlStart = strstr( buf , " " );
    if ( ! urlStart )
        return "/";
    
    urlStart++;
    
    const char * end = strstr( urlStart , " " );
    if ( ! end ){
        end = strstr( urlStart , "\r" );
        if ( ! end ){
            end = strstr( urlStart , "\n" );
        }
    }
    
    if ( ! end ) 
        return "/";
    
    int diff = (int)(end-urlStart);
    if ( diff < 0 || diff > 255 )
        return "/";
    
    return string( urlStart , (int)(end-urlStart) );
}

void MiniWebServer::parseParams( map<string,string> & params , string query ){
    if ( query.size() == 0 )
        return;
    
    while ( query.size() ){
        
        string::size_type amp = query.find( "&" );
        
        string cur;
        if ( amp == string::npos ){
            cur = query;
            query = "";
        }
        else {
            cur = query.substr( 0 , amp );
            query = query.substr( amp + 1 );
        }

        string::size_type eq = cur.find( "=" );
        if ( eq == string::npos )
            continue;
        
        params[cur.substr(0,eq)] = cur.substr(eq+1);
    }
    return;
}

string MiniWebServer::parseMethod( const char * headers ){
    const char * end = strstr( headers , " " );
    if ( ! end )
        return "GET";
    return string( headers , (int)(end-headers) );
}

const char *MiniWebServer::body( const char *buf ) {
    const char *ret = strstr( buf, "\r\n\r\n" );
    return ret ? ret + 4 : ret;
}

bool MiniWebServer::fullReceive( const char *buf ) {
    const char *bod = body( buf );
    if( !bod )
        return false;
    const char *lenString = "Content-Length:";
    const char *lengthLoc = strstr( buf, lenString );
    if ( !lengthLoc )
        return true;
    lengthLoc += strlen( lenString );
    long len = strtol( lengthLoc, 0, 10 );
    if ( long( strlen( bod ) ) == len )
        return true;
    return false;
}

void MiniWebServer::accepted(int s) {
    char buf[4096];
    int len = 0;
    while( 1 ) {
        int x = ::recv(s, buf + len, sizeof(buf) - 1 - len, 0);
        if ( x <= 0 ) {
            return;
        }
        len += x;
        buf[ len ] = 0;
        if ( fullReceive( buf ) )
            break;
    }
    buf[len] = 0;
    
    string responseMsg;
    int responseCode = 599;
    vector<string> headers;
    doRequest(buf, parseURL( buf ), responseMsg, responseCode, headers);

    stringstream ss;
    ss << "HTTP/1.0 " << responseCode;
    if ( responseCode == 200 ) ss << " OK";
    ss << "\r\n";
    if ( headers.empty() ) {
        ss << "Content-Type: text/html\r\n";
    }
    else {
        for ( vector<string>::iterator i = headers.begin(); i != headers.end(); i++ )
            ss << *i << "\r\n";
    }
    ss << "\r\n";
    ss << responseMsg;
    string response = ss.str();

    ::send(s, response.c_str(), response.size(), 0);
}

void MiniWebServer::run() {
    SockAddr from;
    while ( 1 ) {
        int s = accept(sock, (sockaddr *) &from.sa, &from.addressSize);
        if ( s < 0 ) {
            log() << "MiniWebServer: accept() returns " << s << " errno:" << errno << endl;
            sleepmillis(200);
            continue;
        }
        disableNagle(s);
        RARELY log() << "MiniWebServer: connection accepted from " << from.toString() << endl;
        accepted( s );
        closesocket(s);
    }
}