#include "TrbBridgeTrbNetHeaders.hpp"
#include <ctime>

template < typename MAJOR, typename MINOR = uint8_t >
static MAJOR _swapEndianess(MAJOR a) {
   MAJOR b;
   MINOR* src = reinterpret_cast<MINOR*>(&a);
   MINOR* dest = reinterpret_cast<MINOR*>(&b);
   
   constexpr unsigned int steps = sizeof(MAJOR)/sizeof(MINOR);
   
   for(unsigned int i=0; i<steps; i++)
      dest[i] = src[steps-1 - i];
   
   return b;
}

/*************************************************
 * EventHeader
 *************************************************/

size_t TrbBridgeTrbNetEventHeader::setSizeWithPadding(size_t sizeWoPadding) {
   size_t padding = 0;
   if (sizeWoPadding & 0x7) 
      padding = 8 - (sizeWoPadding & 0x7);
   
   size = sizeWoPadding + padding;
   return padding;
}


void TrbBridgeTrbNetEventHeader::writeToBuffer(uint32_t *buffer) const {
   struct tm *parts = std::localtime(&timestamp);
   buffer[0] = size;
   buffer[1] = 0x00030001; // TODO: dis says there's a version included, but cannot find it in files generated by evt builder
   buffer[2] = triggerType;
   buffer[3] = eventNumberPerFile;
   
   buffer[4] = ((parts->tm_year & 0xff) << 16) | (parts->tm_mon << 8) | (parts->tm_mday << 0);
   buffer[5] = (parts->tm_hour << 16) | (parts->tm_min << 8) | (parts->tm_sec  << 0);
   buffer[6] = runNumber;
   buffer[7] = 0;
   
   if (swappedEndianess)
      for(unsigned int i=0; i<8; i++)
         buffer[i] = _swapEndianess(buffer[i]);
}

void TrbBridgeTrbNetEventHeader::loadFromBuffer(const uint32_t* buffer) {
   uint32_t* src = const_cast<uint32_t*>(buffer);
   struct tm parts;

   if (buffer[1] > 0x100000) {
      // need to swap endianess
      src = new uint32_t[8];
      for(unsigned int i = 0; i < 8; i++)
         src[i] = _swapEndianess(buffer[i]);

      swappedEndianess = true;
   } else {
      swappedEndianess = false;
   }
   
   size = src[0];
   triggerType = uint16_t(src[2]);
   eventNumberPerFile = src[3];
   runNumber = src[6];
   
   parts.tm_year = (src[4] >> 16) & 0xff;
   parts.tm_mon  = (src[4] >>  8) & 0xff;
   parts.tm_mday = (src[4] >>  0) & 0xff;
   
   parts.tm_hour = (src[5] >> 16) & 0xff;
   parts.tm_min  = (src[5] >>  8) & 0xff;
   parts.tm_sec  = (src[5] >>  0) & 0xff;
   
   timestamp = std::mktime(&parts);
   
   if (src != buffer) delete[] src;
}

TrbBridgeTrbNetEventHeader TrbBridgeTrbNetEventHeader::operator<<(const uint32_t* buffer) {
   loadFromBuffer(buffer);
   return *this;
}

uint32_t* operator<<(uint32_t* buffer, const TrbBridgeTrbNetEventHeader & evtHdr) {
   evtHdr.writeToBuffer(buffer);
   return buffer;
}

/*************************************************
 * SubEventHeader
 *************************************************/

void TrbBridgeTrbNetSubEventHeader::writeToBuffer(uint32_t *buffer) const {
   buffer[0] = size;
   buffer[1] = 0x00020001 | ((triggerType & 0xf) << 4);
   buffer[2] = subEventId;
   buffer[3] = (triggerNumber << 8) | triggerCode;
   
   if (swappedEndianess)
      for(unsigned int i=0; i<4; i++)
         buffer[i] = _swapEndianess(buffer[i]);
}

void TrbBridgeTrbNetSubEventHeader::loadFromBuffer(const uint32_t* buffer) {
   uint32_t* src = const_cast<uint32_t*>(buffer);

   if (buffer[1] > 0x100000) {
      // need to swap endianess
      src = new uint32_t[4];
      for(unsigned int i = 0; i < 4; i++)
         src[i] = _swapEndianess(buffer[i]);
      
      swappedEndianess = true;
   } else {
      swappedEndianess = false;
   }
   
   size = src[0];
   triggerType = (src[1] >> 4) & 0xf;
   subEventId = src[2];
   triggerCode = uint8_t(src[3]);
   triggerNumber = src[3] >> 8;
   
   if (src != buffer) delete[] src;
}

TrbBridgeTrbNetSubEventHeader TrbBridgeTrbNetSubEventHeader::operator<<(const uint32_t* buffer) {
   loadFromBuffer(buffer);
   return *this;
}
uint32_t* operator<<(uint32_t* buffer, const TrbBridgeTrbNetSubEventHeader & subEvtHdr) {
   subEvtHdr.writeToBuffer(buffer);
   return buffer;
}

/*************************************************
 * SubEventHeader
 *************************************************/
TrbBridgeTrbNetSubSubEventHeader::TrbBridgeTrbNetSubSubEventHeader(unsigned int ssEvtId, unsigned int sze, uint32_t* buf)
   : subSubEventId(ssEvtId)
   , size(sze)
   , payload(buf)
{}
   
std::list<TrbBridgeTrbNetSubSubEventHeader> TrbBridgeTrbNetSubSubEventHeader::extractSubSubEvents(
   const TrbBridgeTrbNetSubEventHeader & subEventHeader, uint32_t* buffer) throw (TrbBridgeTrbNetHeaderException) {
   std::list<TrbBridgeTrbNetSubSubEventHeader> result;
   
   unsigned int wordIdx = 4; // skip sub-event header
   while(wordIdx < subEventHeader.size/4) {
      uint16_t id = buffer[wordIdx] & 0xffff;
      unsigned int sseSize = 4 + 4*(buffer[wordIdx]>>16);   // length (excl. header in words) -> size (incl. header in bytes)
      result.push_back( TrbBridgeTrbNetSubSubEventHeader( id, sseSize, &buffer[wordIdx+1]) );
      
      wordIdx += sseSize / 4;
   }
   
   if (wordIdx != subEventHeader.size/4)
      throw TrbBridgeTrbNetHeaderException("Sum of sub-sub-event length exceeds sub-event size");
   
   return result;
}