/********************************************************************\

  Tentative FACT central control

  - Provides central run number dispatcher.

  Note: Declaring class static ensures destructor is called when 
  exit() is invoked 
         
  Oliver Grimm, March 2010

\********************************************************************/

#define SERVER_NAME "Chief"
#include "Evidence.h"

using namespace std;

// ========= Class Declarations =========

class ChiefClass;

class RunNumberRpc: public DimRpc {

	ChiefClass *Chief;
    void rpcHandler();

  public:
    RunNumberRpc(class ChiefClass *Chief): DimRpc("NextRunNumber", "C", "I"),
	Chief(Chief) {};
};

class ChiefClass: public EvidenceServer {

	RunNumberRpc *RN_Rpc;

  public:
	ChiefClass();
	~ChiefClass();
	
	DimService *LastRunNumber;
	string RunNumFilename;
	int RunNumber;
};

// ========= Class Definitions =========

// Constructor
ChiefClass::ChiefClass(): EvidenceServer(SERVER_NAME) {

  RunNumFilename = GetConfig("RunNumFile");
  RunNumber = -2;
  LastRunNumber = new DimService(SERVER_NAME"/LastRunNumber", RunNumber);
  
  // RPC for dispatching run numbers
  RN_Rpc = new RunNumberRpc(this);
}

// Destructor
ChiefClass::~ChiefClass() {

  delete RN_Rpc;
  delete LastRunNumber;
}


// Remote procedure call: Request for next run number
void RunNumberRpc::rpcHandler() {

  bool OK = true;
  int RunNumber;
  
  // Open file containing last run number
  FILE *RunNumFile = fopen(Chief->RunNumFilename.c_str(), "r+");
  if(RunNumFile == NULL) {
    Chief->Message(Chief->ERROR, "Could not open file '%s' that contains the last run number (%s)", Chief->RunNumFilename.c_str(), strerror(errno));
	OK = false;
  }
  else {
	// Read last run number
	if(fscanf(RunNumFile,"%d", &RunNumber) != 1 ) {
      Chief->Message(Chief->ERROR, "Could not read run number from file '%s'", Chief->RunNumFilename.c_str());
	  OK = false;
	}
	else RunNumber++;

	// Update run number in file
	rewind(RunNumFile);
	if(OK && fprintf(RunNumFile,"%.8u   ",RunNumber) < 0) {
      Chief->Message(Chief->ERROR, "Could not write to run number file '%s'", Chief->RunNumFilename.c_str());
	  OK = false;
	}

	// Close run number file
	if(fclose(RunNumFile) != 0) {
      Chief->Message(Chief->ERROR, "Could not close run number file '%s'", Chief->RunNumFilename.c_str());
	  OK = false;
	}
  }
  
  // Dispatch real run number only if all successful
  if (!OK) RunNumber = -1;
  Chief->RunNumber = RunNumber;
  setData(RunNumber);
  Chief->LastRunNumber->updateService();
  Chief->Message(Chief->INFO, "Dispatched run number %d", RunNumber);
}

//
// Main program
//
int main() {

  static ChiefClass TheBoss;

  // Sleep until exit requested
  while (!TheBoss.ExitRequest) pause();
}