/*
 * FragmentController.hpp
 *
 *  Created on: Nov 27, 2011
 *      Author: heber
 */

#ifndef FRAGMENTCONTROLLER_HPP_
#define FRAGMENTCONTROLLER_HPP_

// include config.h
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <boost/asio.hpp>
#include <string>
#include <vector>

#include "Connection.hpp"
#include "FragmentJob.hpp"
#include "FragmentResult.hpp"

/** The FragmentController sends bunches of jobs to a FragmentScheduler,
 *  waits for their calculation and is called when they are done. Then,
 *  he loads the bunch of results from the Scheduler.
 *
 * While the FragmentScheduler and FragmentWorker rather act on their own
 * this is the piece to implant into the user software to allow for
 * communication with the Server/Worker duo to perform the calculation
 * of the fragments on distant computers.
 */
class FragmentController
{
public:
  FragmentController(boost::asio::io_service& io_service, const std::string& _host, const std::string& _service);
  ~FragmentController();

  class Operation {
  public:
    Operation(Connection &_connection, const std::string& _host, const std::string& _service);
    virtual ~Operation();
  public:
    /// The Connection to the server.
    Connection &connection_;

    // virtual function pointer to the operation to do
    virtual void operator()() = 0;

    /// Handle completion of an operation.
    void handle_FinishOperation(const boost::system::error_code& e);

    enum Exitflag_t {
      OkFlag = 0,
      ErrorFlag = 255
    };

    // get the exit flag of the last operations
    size_t getExitflag() const
    {
      return Exitflag;
    }

  protected:
    /// internal function to resolve host name and ip address
    boost::asio::ip::tcp::resolver::iterator getEndpointIterator();

    /// internal function to disconnect from server
    void disconnect();

  protected:
    /// host name of server
    const std::string host;

    // service to connect to to
    const std::string service;

    /// flag of operation to give on program exit
    enum Exitflag_t Exitflag;
  };

  class ReceiveJobsOperation : public Operation {
  public:
    /// Constructor for class ReceiveJobsOperation.
    ReceiveJobsOperation(Connection &_connection, const std::string& _host, const std::string& _service) :
      Operation(_connection, _host, _service) {}
    /// Destructor for class ReceiveJobsOperation
    ~ReceiveJobsOperation() {}

  public:
    /// Placing receive jobs operations into an io_service
    virtual void operator()();

    /// Handle completion of a calculate operation.
    void handle_connect_calc(const boost::system::error_code& e,
        boost::asio::ip::tcp::resolver::iterator endpoint_iterator);

    /// Callback function when bunch of jobs have been sent.
    void handle_SendJobs(const boost::system::error_code& e);

    /// Handle completion of an operation.
    void handle_FinishOperation(const boost::system::error_code& e);

    /// internal function to connect to server and send jobs for calculation
    void connect_calc();

    /// Setter for jobs
    void addJobs(const std::vector<FragmentJob> &jobs);

    /// Getter for number of size of jobs
    size_t getPresentJobs() const;

  protected:
    /// bunch of jobs
    std::vector<FragmentJob> jobs;
  };

  struct CheckResultsOperation : public Operation  {
  public:
    /// Constructor for class CheckResultsOperation.
    CheckResultsOperation(Connection &_connection, const std::string& _host, const std::string& _service) :
      Operation(_connection, _host, _service),
      doneJobs(0)
    {}
    /// Destructor for class CheckResultsOperation
    ~CheckResultsOperation() {}

  public:
    // placing receive jobs operations into an io_service
    virtual void operator()();

    /// Handle completion of a CheckResults operation.
    void handle_connect_check(const boost::system::error_code& e,
        boost::asio::ip::tcp::resolver::iterator endpoint_iterator);

    /// Callback function when doneJobs have been received.
    void handle_ReceiveDoneJobs(const boost::system::error_code& e);

    /// Handle completion of an operation.
    void handle_FinishOperation(const boost::system::error_code& e);

    /// internal function to connect to server and check done jobs
    void connect_check();

    /// Getter for doneJobs
    size_t getDoneJobs() const;

  protected:
    /// currently calculated results
    size_t doneJobs;
  };

  struct SendResultsOperation : public Operation  {
  public:
    /// Constructor for class SendResultsOperation.
    SendResultsOperation(Connection &_connection, const std::string& _host, const std::string& _service) :
      Operation(_connection, _host, _service) {}
    /// Destructor for class SendResultsOperation
    ~SendResultsOperation() {}

  public:
    // placing receive jobs operations into an io_service
    virtual void operator()();

    /// Handle completion of a GetResults operation.
    void handle_connect_get(const boost::system::error_code& e,
        boost::asio::ip::tcp::resolver::iterator endpoint_iterator);

          /// Callback function when results are about to be received.
          void handle_ReceivingResults(const boost::system::error_code& e);

          /// Callback function when results have been received.
          void handle_ReceivedResults(const boost::system::error_code& e);

    /// internal function to connect to server and receive calculated results
    void connect_get();

    /// Getter for results
    std::vector<FragmentResult> getResults();

  protected:
    /// bunch of results
    std::vector<FragmentResult> results;
  };

  struct ShutdownOperation : public Operation  {
  public:
    /// Constructor for class ShutdownOperation.
    ShutdownOperation(Connection &_connection, const std::string& _host, const std::string& _service) :
      Operation(_connection, _host, _service) {}
    /// Destructor for class ShutdownOperation
    ~ShutdownOperation() {}

  public:
    // placing receive jobs operations into an io_service
    virtual void operator()();

    /// Handle completion of a Shutdown operation.
    void handle_connect_shutdown(const boost::system::error_code& e,
        boost::asio::ip::tcp::resolver::iterator endpoint_iterator);

    /// internal function to connect to server and receive calculated results
    void connect_shutdown();

  };

protected:
  /// The Connection to the server.
  Connection connection_;

public:

  ReceiveJobsOperation recjobs;
  CheckResultsOperation checkres;
  SendResultsOperation  sendres;
  ShutdownOperation shutdown;

  // get the exit flag of the last operations
  size_t getExitflag() const
  {
    if (recjobs.getExitflag() != 0)
      return recjobs.getExitflag();
    if (checkres.getExitflag() != 0)
      return checkres.getExitflag();
    if (sendres.getExitflag() != 0)
      return sendres.getExitflag();
    if (shutdown.getExitflag() != 0)
      return shutdown.getExitflag();
    return 0;
  }

  /// place number of jobs into this controller
  void addJobs(const std::vector<FragmentJob> &jobs)
  {
    recjobs.addJobs(jobs);
  }

  /// get the results for the current jobs
  std::vector<FragmentResult> getResults()
  {
    return sendres.getResults();
  }

  /// Getter for doneJobs
  size_t getDoneJobs() const
  {
    return checkres.getDoneJobs();
  }

  /// Getter for number of jobs in the queue
  size_t getPresentJobs() const
  {
    return recjobs.getPresentJobs();
  }

private:
  /// host name of server
  const std::string host;

  // service to connect to to
  const std::string service;
};

#endif /* FRAGMENTCONTROLLER_HPP_ */