/*
 *  © 2022 Harald Barth
 *  © 2020-2021 Chris Harlow
 *  © 2020 Gregor Baues
 *  All rights reserved.
 *
 *  This file is part of CommandStation-EX
 *
 *  This 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 3 of the License, or
 *  (at your option) any later version.
 *
 *  It 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 CommandStation.  If not, see <https://www.gnu.org/licenses/>.
 */

#include <Arduino.h>
#include "CommandDistributor.h"
#include "SerialManager.h"
#include "WiThrottle.h"
#include "DIAG.h"
#include "defines.h"
#include "DCCWaveform.h"
#include "DCC.h"
#include "TrackManager.h"


#if WIFI_ON || ETHERNET_ON || defined(SERIAL1_COMMANDS) || defined(SERIAL2_COMMANDS) || defined(SERIAL3_COMMANDS)
// use a buffer to allow broadcast
StringBuffer * CommandDistributor::broadcastBufferWriter=new StringBuffer();
template<typename... Targs> void CommandDistributor::broadcastReply(clientType type, Targs... msg){
  broadcastBufferWriter->flush();
  StringFormatter::send(broadcastBufferWriter, msg...);
  broadcastToClients(type);
}
#else
// on a single USB connection config, write direct to Serial and ignore flush/shove
template<typename... Targs> void CommandDistributor::broadcastReply(clientType type, Targs... msg){
  (void)type; //shut up compiler warning
  StringFormatter::send(&Serial, msg...);
}
#endif 

#ifdef CD_HANDLE_RING
  // wifi or ethernet ring streams with multiple client types
  RingStream *  CommandDistributor::ring=0;
  CommandDistributor::clientType  CommandDistributor::clients[8]={
    NONE_TYPE,NONE_TYPE,NONE_TYPE,NONE_TYPE,NONE_TYPE,NONE_TYPE,NONE_TYPE,NONE_TYPE};

// Parse is called by Withrottle or Ethernet interface to determine which
// protocol the client is using and call the appropriate part of dcc++Ex
void  CommandDistributor::parse(byte clientId,byte * buffer, RingStream * stream) {
  if (Diag::WIFI && Diag::CMD)
    DIAG(F("Parse C=%d T=%d B=%s"),clientId, clients[clientId], buffer);
  ring=stream;

  // First check if the client is not known
  // yet and in that case determinine type
  // NOTE: First character of transmission determines if this
  // client is using the DCC++ protocol where all commands start
  // with '<'
  if (clients[clientId] == NONE_TYPE) {
    if (buffer[0] == '<')
      clients[clientId]=COMMAND_TYPE;
    else
      clients[clientId]=WITHROTTLE_TYPE;
  }

  // mark buffer that is sent to parser
  ring->mark(clientId);

  // When type is known, send the string
  // to the right parser
  if (clients[clientId] == COMMAND_TYPE) {
    DCCEXParser::parse(stream, buffer, ring);
  } else if (clients[clientId] == WITHROTTLE_TYPE) {
    WiThrottle::getThrottle(clientId)->parse(ring, buffer);
  }

  if (ring->peekTargetMark()!=RingStream::NO_CLIENT) {
    // The commit call will either write the length bytes
    // OR rollback to the mark because the reply is empty
    // or the command generated more output than fits in
    // the buffer
    if (!ring->commit()) {
      DIAG(F("OUTBOUND FULL processing cmd:%s"),buffer);
    }
  } else {
    DIAG(F("CD parse: was alredy committed")); //XXX Could have been committed by broadcastClient?!
  }
}

void CommandDistributor::forget(byte clientId) {
  // keep for later if (clients[clientId]==WITHROTTLE_TYPE) WiThrottle::forget(clientId);
  clients[clientId]=NONE_TYPE;
}
#endif 

// This will not be called on a uno 
void CommandDistributor::broadcastToClients(clientType type) {

  byte rememberClient;
  (void)rememberClient; // shut up compiler warning

  // Broadcast to Serials
  if (type==COMMAND_TYPE) SerialManager::broadcast(broadcastBufferWriter->getString());

#ifdef CD_HANDLE_RING
  // If we are broadcasting from a wifi/eth process we need to complete its output
  // before merging broadcasts in the ring, then reinstate it in case
  // the process continues to output to its client.
  if (ring) {
    if ((rememberClient = ring->peekTargetMark()) != RingStream::NO_CLIENT) {
      //DIAG(F("CD precommit client %d"), rememberClient);
      ring->commit();
    }
    // loop through ring clients
    for (byte clientId=0; clientId<sizeof(clients); clientId++) {
      if (clients[clientId]==type)  {
	//DIAG(F("CD mark client %d"), clientId);
	ring->mark(clientId);
	ring->print(broadcastBufferWriter->getString());
	//DIAG(F("CD commit client %d"), clientId);
	ring->commit();
      }
    }
    // at this point ring is committed (NO_CLIENT) either from
    // 4 or 13 lines above.
    if (rememberClient != RingStream::NO_CLIENT) {
      //DIAG(F("CD postmark client %d"), rememberClient);
      ring->mark(rememberClient);
    }
  }
#endif
}

// Public broadcast functions below 
void  CommandDistributor::broadcastSensor(int16_t id, bool on ) {
  broadcastReply(COMMAND_TYPE, F("<%c %d>\n"), on?'Q':'q', id);
}

void  CommandDistributor::broadcastTurnout(int16_t id, bool isClosed ) {
  // For DCC++ classic compatibility, state reported to JMRI is 1 for thrown and 0 for closed;
  // The string below contains serial and Withrottle protocols which should
  // be safe for both types.
  broadcastReply(COMMAND_TYPE, F("<H %d %d>\n"),id, !isClosed);
#ifdef CD_HANDLE_RING
  broadcastReply(WITHROTTLE_TYPE, F("PTA%c%d\n"), isClosed?'2':'4', id);
#endif
}

void  CommandDistributor::broadcastLoco(byte slot) {
  DCC::LOCO * sp=&DCC::speedTable[slot];
  broadcastReply(COMMAND_TYPE, F("<l %d %d %d %l>\n"), sp->loco,slot,sp->speedCode,sp->functions);
#ifdef CD_HANDLE_RING
  WiThrottle::markForBroadcast(sp->loco);
#endif
}

void  CommandDistributor::broadcastPower() {
  bool main=TrackManager::getMainPower()==POWERMODE::ON;
  bool prog=TrackManager::getProgPower()==POWERMODE::ON;
  bool join=TrackManager::isJoined();
  const FSH * reason=F("");
  char state='1';
  if (main && prog && join) reason=F(" JOIN");
  else if (main && prog);
  else if (main) reason=F(" MAIN");
  else if (prog) reason=F(" PROG");
  else state='0';
  broadcastReply(COMMAND_TYPE, F("<p %c%S>\n"),state,reason);
#ifdef CD_HANDLE_RING
  broadcastReply(WITHROTTLE_TYPE, F("PPA%c\n"), main?'1':'0');
#endif
  LCD(2,F("Power %S%S"),state=='1'?F("On"):F("Off"),reason);  
}

void CommandDistributor::broadcastText(const FSH * msg) {
  broadcastReply(COMMAND_TYPE, F("<I %S>\n"),msg);
#ifdef CD_HANDLE_RING
  broadcastReply(WITHROTTLE_TYPE, F("Hm%S\n"), msg);
#endif
}