// ==================================================================
// Author: Jean-Michel Richer
// Email: jean-michel.richer@univ-angers.fr
// Date: Aug 2020
// Last modified: November 2020
// Purpose: interface and class to facilitate use of MPI
// ==================================================================

#include "ezmpi.h"

using namespace ez::mpi;

void Process::find_cpu_name() {
	char name[MPI::MAX_PROCESSOR_NAME];
	int length;
	
	memset(name, 0, MPI::MAX_PROCESSOR_NAME);
	MPI::Get_processor_name(name,length);
	m_name = name;
}
 
void Process::init() {
	m_max = MPI::COMM_WORLD.Get_size();
	m_id = MPI::COMM_WORLD.Get_rank();
	find_cpu_name();
	m_pid = getpid();
	if (m_verbose_flag) {
		tmp_log << "pid=" << m_pid << ", id=" << m_id << endl;
		flush();
	}

}

Process::Process(int argc, char *argv[], bool verbose, bool log) {
	m_remote = 0;
	m_message_tag = 0;
	m_verbose_flag = verbose;
	m_log_flag = log;
	finalize_already_called = false;
	MPI::Init(argc, argv);
	init();
}

void Process::logs(ostream& out) {
	m_verbose_flag = m_log_flag = false;
	if (m_id == 0) {
		out.flush();
		out << std::endl;
		out << "====================" << std::endl;
		out << "=== FINAL RESULT ===" << std::endl;
		out << "====================" << std::endl;	
		out << "---------------------" << std::endl;
		out << "CPU " << m_id << " (pid=" << pid() << ")" << std::endl;
		out << "---------------------" << std::endl;
		out << log_stream.str();
		out.flush();
		remote( 1 );
		int token = -255;
		send( token );
	} else {
		remote( m_id - 1 );
		int token;
		recv(token);			
		out << "---------------------" << std::endl;
		out << "CPU " << m_id << " (pid=" << pid() << ")" << std::endl;
		out << "---------------------" << std::endl;
		out << log_stream.str();
		out.flush();
		if (m_id < m_max - 1) {
			remote( m_id + 1 );
			token = -255;
			send(token);
		}
		
	}
	
	
}
	

void Process::finalize() {

	if (!finalize_already_called) { 
		finalize_already_called = true;
		MPI::COMM_WORLD.Barrier();
		MPI::Finalize();
	}

}

Process::~Process() {
	
	if (!finalize_already_called) {	
		finalize_already_called = true;
		MPI::COMM_WORLD.Barrier();
		MPI::Finalize();
	}

}

int Process::pid() {
	return m_pid;
}

int Process::id() {
	return m_id;
}

int Process::rank() {
	return m_id;
}

int Process::max() {
	return m_max;
}
	
string Process::name() {
	return m_name;
}
	
void Process::tag(int tag) {
	m_message_tag = tag;
}

void Process::remote(int rmt) {
	m_remote = rmt;
}

void Process::synchronize() {
	MPI::COMM_WORLD.Barrier();
}

// --------------------------
// output
// --------------------------

const std::string currentDateTime() {
    time_t     now = time(0);
    struct tm  tstruct;
    char       buf[80];
    tstruct = *localtime(&now);
  	//strftime(buf, sizeof(buf), "%Y-%m-%d.%X [%s]", &tstruct);
    strftime(buf, sizeof(buf), "%X", &tstruct);
    
    return buf;
}

void Process::flush() {
	string str = currentDateTime(); 
	if (m_log_flag) {
		log_stream << str << " cpu " << m_id << "/" << m_max << ": " << tmp_log.str();
	}
	if (m_verbose_flag) {
		cerr << str << " cpu " << m_id << "/" << m_max << ": " << tmp_log.str();
	}
	tmp_log.str("");
}

void Process::print(char v) {
	tmp_log << v;
}

void Process::print(int v) {
	tmp_log << v;
}

void Process::print(string v) {
	tmp_log << v;
}

void Process::print(float v) {
	tmp_log << v;
}

void Process::print(double v) {
	tmp_log << v;
}