/* <!-- copyright */
/*
 * aria2 - The high speed download utility
 *
 * Copyright (C) 2009 Tatsuhiro Tsujikawa
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * In addition, as a special exception, the copyright holders give
 * permission to link the code of portions of this program with the
 * OpenSSL library under certain conditions as described in each
 * individual source file, and distribute linked combinations
 * including the two.
 * You must obey the GNU General Public License in all respects
 * for all of the code used other than OpenSSL.  If you modify
 * file(s) with this exception, you may extend this exception to your
 * version of the file(s), but you are not obligated to do so.  If you
 * do not wish to do so, delete this exception statement from your
 * version.  If you delete this exception statement from all source
 * files in the program, then also delete it here.
 */
/* copyright --> */
#include "HttpServerBodyCommand.h"
#include "SocketCore.h"
#include "DownloadEngine.h"
#include "HttpServer.h"
#include "HttpHeader.h"
#include "Logger.h"
#include "LogFactory.h"
#include "RequestGroup.h"
#include "RequestGroupMan.h"
#include "RecoverableException.h"
#include "HttpServerResponseCommand.h"
#include "OptionParser.h"
#include "OptionHandler.h"
#include "wallclock.h"
#include "util.h"
#include "fmt.h"
#include "SocketRecvBuffer.h"
#include "json.h"
#include "DlAbortEx.h"
#include "message.h"
#include "RpcMethod.h"
#include "RpcMethodFactory.h"
#include "RpcRequest.h"
#include "RpcResponse.h"
#ifdef ENABLE_XML_RPC
# include "XmlRpcRequestProcessor.h"
# include "XmlRpcRequestParserStateMachine.h"
#endif // ENABLE_XML_RPC

namespace aria2 {

HttpServerBodyCommand::HttpServerBodyCommand
(cuid_t cuid,
 const SharedHandle<HttpServer>& httpServer,
 DownloadEngine* e,
 const SharedHandle<SocketCore>& socket)
  : Command(cuid),
    e_(e),
    socket_(socket),
    httpServer_(httpServer)
{
  // To handle Content-Length == 0 case
  setStatus(Command::STATUS_ONESHOT_REALTIME);
  e_->addSocketForReadCheck(socket_, this);
  if(!httpServer_->getSocketRecvBuffer()->bufferEmpty()) {
    e_->setNoWait(true);
  }
}

HttpServerBodyCommand::~HttpServerBodyCommand()
{
  e_->deleteSocketForReadCheck(socket_, this);
}

namespace {
rpc::RpcResponse
createJsonRpcErrorResponse
(int code,
 const std::string& msg,
 const SharedHandle<ValueBase>& id)
{
  SharedHandle<Dict> params = Dict::g();
  params->put("code", Integer::g(code));
  params->put("message", msg);
  rpc::RpcResponse res(code, params, id);
  return res;
}
} // namespace

namespace {
std::string getJsonRpcContentType(bool script)
{
  return script ? "text/javascript" : "application/json-rpc";
}
} // namespace

void HttpServerBodyCommand::sendJsonRpcResponse
(const rpc::RpcResponse& res,
 const std::string& callback)
{
  bool gzip = httpServer_->supportsGZip();
  std::string responseData = res.toJson(callback, gzip);
  if(res.code == 0) {
    httpServer_->feedResponse(responseData,
                              getJsonRpcContentType(!callback.empty()));
  } else {
    httpServer_->disableKeepAlive();
    std::string httpCode;
    switch(res.code) {
    case -32600:
      httpCode = "400 Bad Request";
      break;
    case -32601:
      httpCode = "404 Not Found";
      break;
    default:
      httpCode = "500 Internal Server Error";
    };
    httpServer_->feedResponse(httpCode, A2STR::NIL,
                              responseData,
                              getJsonRpcContentType(!callback.empty()));
  }
  addHttpServerResponseCommand();
}

void HttpServerBodyCommand::sendJsonRpcBatchResponse
(const std::vector<rpc::RpcResponse>& results,
 const std::string& callback)
{
  bool gzip = httpServer_->supportsGZip();
  std::string responseData = rpc::toJsonBatch(results, callback, gzip);
  httpServer_->feedResponse(responseData,
                            getJsonRpcContentType(!callback.empty()));
  addHttpServerResponseCommand();
}

void HttpServerBodyCommand::addHttpServerResponseCommand()
{
  Command* command =
    new HttpServerResponseCommand(getCuid(), httpServer_, e_, socket_);
  e_->addCommand(command);
  e_->setNoWait(true);
}

rpc::RpcResponse
HttpServerBodyCommand::processJsonRpcRequest(const Dict* jsondict)
{

  SharedHandle<ValueBase> id = jsondict->get("id");
  if(!id) {
    return createJsonRpcErrorResponse(-32600, "Invalid Request.", Null::g());
  }
  const String* methodName = asString(jsondict->get("method"));
  if(!methodName) {
    return createJsonRpcErrorResponse(-32600, "Invalid Request.", id);
  }
  SharedHandle<List> params;
  const SharedHandle<ValueBase>& tempParams = jsondict->get("params");
  if(asList(tempParams)) {
    params = static_pointer_cast<List>(tempParams);
  } else if(!tempParams) {
    params = List::g();
  } else {
    // TODO No support for Named params
    return createJsonRpcErrorResponse(-32602, "Invalid params.", id);
  }
  rpc::RpcRequest req(methodName->s(), params, id);
  req.jsonRpc = true;
  SharedHandle<rpc::RpcMethod> method;
  try {
    method = rpc::RpcMethodFactory::create(req.methodName);
  } catch(RecoverableException& e) {
    A2_LOG_INFO_EX(EX_EXCEPTION_CAUGHT, e);
    return createJsonRpcErrorResponse(-32601, "Method not found.", id);
  }
  A2_LOG_INFO(fmt("Executing RPC method %s", req.methodName.c_str()));
  rpc::RpcResponse res = method->execute(req, e_);
  return res;
}

bool HttpServerBodyCommand::execute()
{
  if(e_->getRequestGroupMan()->downloadFinished() || e_->isHaltRequested()) {
    return true;
  }
  try {
    if(socket_->isReadable(0) ||
       !httpServer_->getSocketRecvBuffer()->bufferEmpty() ||
       httpServer_->getContentLength() == 0) {
      timeoutTimer_ = global::wallclock;

      if(httpServer_->receiveBody()) {
        std::string reqPath = httpServer_->getRequestPath();
        reqPath.erase(std::find(reqPath.begin(), reqPath.end(), '#'),
                      reqPath.end());
        std::string query(std::find(reqPath.begin(), reqPath.end(), '?'),
                          reqPath.end());
        reqPath.erase(reqPath.size()-query.size(), query.size());
        // Do something for requestpath and body
        if(reqPath == "/rpc") {
#ifdef ENABLE_XML_RPC
          rpc::RpcRequest req =
            rpc::XmlRpcRequestProcessor().parseMemory(httpServer_->getBody());
          SharedHandle<rpc::RpcMethod> method =
            rpc::RpcMethodFactory::create(req.methodName);
          A2_LOG_INFO(fmt("Executing RPC method %s", req.methodName.c_str()));
          rpc::RpcResponse res = method->execute(req, e_);
          bool gzip = httpServer_->supportsGZip();
          std::string responseData = res.toXml(gzip);
          httpServer_->feedResponse(responseData, "text/xml");
          addHttpServerResponseCommand();
#endif // ENABLE_XML_RPC
          return true;
        } else if(reqPath == "/jsonrpc") {
          std::string callback;
          SharedHandle<ValueBase> json;
          try {
            if(httpServer_->getMethod() == "GET") {
              json::JsonGetParam param = json::decodeGetParams(query);
              callback = param.callback;
              json = json::decode(param.request);
            } else {
              json = json::decode(httpServer_->getBody());
            }
          } catch(RecoverableException& e) {
            A2_LOG_INFO_EX
              (fmt("CUID#%lld - Failed to parse JSON-RPC request",
                   getCuid()),
               e);
            rpc::RpcResponse res
              (createJsonRpcErrorResponse(-32700, "Parse error.", Null::g()));
            sendJsonRpcResponse(res, callback);
            return true;
          }
          const Dict* jsondict = asDict(json);
          if(jsondict) {
            rpc::RpcResponse res = processJsonRpcRequest(jsondict);
            sendJsonRpcResponse(res, callback);
          } else {
            const List* jsonlist = asList(json);
            if(jsonlist) {
              // This is batch call
              std::vector<rpc::RpcResponse> results;
              for(List::ValueType::const_iterator i = jsonlist->begin(),
                    eoi = jsonlist->end(); i != eoi; ++i) {
                const Dict* jsondict = asDict(*i);
                if(jsondict) {
                  rpc::RpcResponse r = processJsonRpcRequest(jsondict);
                  results.push_back(r);
                }
              }
              sendJsonRpcBatchResponse(results, callback);
            } else {
              rpc::RpcResponse res
                (createJsonRpcErrorResponse
                 (-32600, "Invalid Request.", Null::g()));
              sendJsonRpcResponse(res, callback);
            }
          }
          return true;
        } else {
          return true;
        }
      } else {
        e_->addCommand(this);
        return false;
      } 
    } else {
      if(timeoutTimer_.difference(global::wallclock) >= 30) {
        A2_LOG_INFO("HTTP request body timeout.");
        return true;
      } else {
        e_->addCommand(this);
        return false;
      }
    }
  } catch(RecoverableException& e) {
    A2_LOG_INFO_EX
      (fmt("CUID#%lld - Error occurred while reading HTTP request body",
           getCuid()),
       e);
    return true;
  }

}

} // namespace aria2