#include <iostream>
#include <iomanip>
#include <sstream>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/stat.h>

#ifdef _DMTCP
#include "dmtcpaware.h"
#endif

#include "trick/DMTCP.hh"
#include "trick/CheckPointRestart.hh"
#include "trick/MemoryManager.hh"
#include "trick/SimObject.hh"
#include "trick/Executive.hh"
#include "trick/exec_proto.hh"
#include "trick/exec_proto.h"
#include "trick/command_line_protos.h"
#include "trick/message_proto.h"
#include "trick/message_type.h"
#include "trick/TrickConstant.hh"

Trick::CheckPointRestart * the_cpr ;

Trick::CheckPointRestart::CheckPointRestart() {

    int num_classes = 0 ;

    pre_init_checkpoint = false ;
    post_init_checkpoint = false ;
    end_checkpoint = false ;
    safestore_enabled = false ;
    cpu_num = -1 ;
    safestore_time = TRICK_MAX_LONG_LONG ;
    load_checkpoint_file_name.clear() ;

    write_checkpoint_job = NULL ;
    safestore_checkpoint_job = NULL ;

    class_map["checkpoint"] = num_classes ;
    class_to_queue[num_classes++] = &checkpoint_queue ;

    class_map["post_checkpoint"] = num_classes ;
    class_to_queue[num_classes++] = &post_checkpoint_queue ;

    class_map["preload_checkpoint"] = num_classes ;
    class_to_queue[num_classes++] = &preload_checkpoint_queue ;

    class_map["restart"] = num_classes ;
    class_to_queue[num_classes++] = &restart_queue ;

    the_cpr = this ;
}

int Trick::CheckPointRestart::set_pre_init_checkpoint(bool yes_no) {
    pre_init_checkpoint = yes_no ;
    return(0) ;
}

int Trick::CheckPointRestart::set_post_init_checkpoint(bool yes_no) {
    post_init_checkpoint = yes_no ;
    return(0) ;
}

int Trick::CheckPointRestart::set_end_checkpoint(bool yes_no) {
    end_checkpoint = yes_no ;
    return(0) ;
}

int Trick::CheckPointRestart::set_safestore_enabled(bool yes_no) {
    safestore_enabled = yes_no ;
    return(0) ;
}

int Trick::CheckPointRestart::dmtcp_set_safestore_enabled(bool yes_no) {
    dmtcp_safestore_enabled = yes_no ;
    return(0) ;
}

int Trick::CheckPointRestart::set_cpu_num(int in_cpu_num) {
    if ( in_cpu_num <= 0 ) {
        cpu_num = -1 ;
    } else {
        cpu_num = in_cpu_num ;
    }
    return(0) ;
}


const char * Trick::CheckPointRestart::get_output_file() {
    return output_file.c_str() ;
}

const char * Trick::CheckPointRestart::get_load_file() {
    return load_checkpoint_file_name.c_str() ;
}

int Trick::CheckPointRestart::find_write_checkpoint_jobs(std::string sim_object_name) {

    write_checkpoint_job = exec_get_job(std::string(sim_object_name + ".write_checkpoint").c_str()) ;
    if ( write_checkpoint_job == NULL ) {
        exec_terminate_with_return(-1 , __FILE__ , __LINE__ , "CheckPointRestart could not find write_checkpoint job" ) ;
    } else {
        write_checkpoint_job->next_tics = TRICK_MAX_LONG_LONG ;
    }

    safestore_checkpoint_job = exec_get_job(std::string(sim_object_name + ".safestore_checkpoint").c_str()) ;
    if ( safestore_checkpoint_job == NULL ) {
        exec_terminate_with_return(-1 , __FILE__ , __LINE__ , "CheckPointRestart could not find safestore_checkpoint job" ) ;
    } else {
        safestore_checkpoint_job->next_tics = TRICK_MAX_LONG_LONG ;
    }

    return(0) ;
}

int Trick::CheckPointRestart::checkpoint(double in_time) {

    long long curr_time = exec_get_time_tics() ;
    long long new_time ;

    new_time = (long long)(in_time * exec_get_time_tic_value()) ;

    if (new_time >= curr_time ) {
        checkpoint_times.push(new_time) ;
        if ( new_time < write_checkpoint_job->next_tics ) {
            write_checkpoint_job->next_tics = new_time ;
        }
        //std::cout << "\033[33mSET CHECKPOINT TIME " << in_time << " " << new_time << "\033[0m" << std::endl ;
    } else {
        message_publish(MSG_ERROR, "Checkpoint time specified in the past. specified %f, current_time %f\n",
         in_time , exec_get_sim_time()) ;
    }

    return(0) ;
}

int Trick::CheckPointRestart::set_safestore_time(double in_time) {

    long long software_frame_tics ;

    safestore_period = (long long)(in_time * exec_get_time_tic_value()) ;
    software_frame_tics = exec_get_software_frame_tics() ;

    if ( safestore_period % software_frame_tics ) {
        safestore_period = ((safestore_time / software_frame_tics) + 1 ) * software_frame_tics ;
    }
    safestore_time = safestore_period ;

    if ( safestore_checkpoint_job != NULL ) {
        safestore_checkpoint_job->next_tics = safestore_time ;
    }

    return(0) ;
}

int Trick::CheckPointRestart::dmtcp_set_safestore_time(double in_time) {

    long long software_frame_tics ;

    if ( in_time < 10 ) {
        std::cout << "\nA DMTCP Safestore Interval less than 10 seconds is not recommended.\n\n";
    }

    dmtcp_safestore_period = (long long)(in_time * exec_get_time_tic_value()) ;
    software_frame_tics = exec_get_software_frame_tics() ;

    if ( dmtcp_safestore_period % software_frame_tics ) {
        dmtcp_safestore_period = ((dmtcp_safestore_time / software_frame_tics) + 1 ) * software_frame_tics ;
    }
    dmtcp_safestore_time = dmtcp_safestore_period ;

    return(0) ;
}

int Trick::CheckPointRestart::checkpoint(std::string file_name, bool print_status, std::string obj_list_str ) {

    // first, empty the sim obj list to make sure there is nothing left from last time
    obj_list.clear();

    if (obj_list_str.compare("")) {
        const char * tok = strtok((char*)obj_list_str.c_str(), ",");
        while (tok != NULL) {
            obj_list.push_back(tok);
            tok = strtok(NULL, ",");
        }
    }

    do_checkpoint(file_name, print_status) ;

    return(0) ;
}

int Trick::CheckPointRestart::do_checkpoint(std::string file_name, bool print_status) {

    JobData * curr_job ;
    pid_t pid;

    if ( ! file_name.compare("") ) {
        std::stringstream file_name_stream ;
        file_name_stream << "chkpnt_" << std::fixed << std::setprecision(6) << exec_get_sim_time() ;
        file_name = file_name_stream.str() ;
    }
    output_file = std::string(command_line_args_get_output_dir()) + "/" + file_name ;

    checkpoint_queue.reset_curr_index() ;
    while ( (curr_job = checkpoint_queue.get_next_job()) != NULL ) {
        curr_job->parent_object->call_function(curr_job) ;
    }

    if ( cpu_num != -1 ) {
    // if the user specified a cpu number for the checkpoint, fork a process to write the checkpoint
        if ((pid = fork()) == 0) {
#if __linux
            if ( cpu_num >= 0 ) {
                unsigned long mask;
                mask = 1 << cpu_num ;
                syscall((long) __NR_sched_setaffinity, 0, sizeof(mask), &mask);
            }
#endif
#if __APPLE__
            if ( cpu_num >= 0 ) {
            }
#endif
            if (obj_list.empty()) {
                trick_MM->write_checkpoint(output_file.c_str()) ;
            } else {
                trick_MM->write_checkpoint(output_file.c_str(), obj_list);
            }
            _Exit(0) ;
        }
    } 
    else {
    // no fork
        if (obj_list.empty()) {
            trick_MM->write_checkpoint(output_file.c_str()) ;
        } else {
            trick_MM->write_checkpoint(output_file.c_str(), obj_list);
        }
    }

    post_checkpoint_queue.reset_curr_index() ;
    while ( (curr_job = post_checkpoint_queue.get_next_job()) != NULL ) {
        curr_job->parent_object->call_function(curr_job) ;
    }

    if ( print_status ) {
        message_publish(MSG_INFO, "Dumped ASCII Checkpoint %s.\n", file_name.c_str()) ;
    }

    return 0 ;
}

int Trick::CheckPointRestart::write_checkpoint() {

    long long curr_time = exec_get_time_tics() ;

    // checkpoint time is set in a read event that occurs at top of frame
    if ( curr_time == checkpoint_times.top() ) {

        // remove all times at the top of the queue that match the current time.
        while ( !checkpoint_times.empty() and (checkpoint_times.top() == curr_time) ) {
            checkpoint_times.pop() ;
        }

        if ( !checkpoint_times.empty() ) {
            write_checkpoint_job->next_tics = checkpoint_times.top() ;
        } else {
            write_checkpoint_job->next_tics = TRICK_MAX_LONG_LONG ;
        }

        double sim_time = exec_get_sim_time() ;
        std::stringstream chk_name_stream ;

        chk_name_stream << "chkpnt_" << std::fixed << std::setprecision(6) << sim_time ;

        checkpoint( chk_name_stream.str() );

    }

    return(0) ;
}

void  Trick::CheckPointRestart::setDMTCPFilename( std::string file_name __attribute__((unused))) {
#ifdef _DMTCP
       if (!file_name.compare("") ) {

           std::stringstream file_name_stream ;
           SIM_MODE sim_mode ;
           sim_mode = exec_get_mode() ;

           if (sim_mode == Initialization)
               file_name_stream << "dmtcp_chkpnt_init";
           else
               file_name_stream << "dmtcp_chkpnt_" << std::fixed << std::setprecision(2) << exec_get_sim_time() ;

           file_name = file_name_stream.str() ;
       }

       dmtcp_job_queue( file_name );
#endif
}

int Trick::CheckPointRestart::dmtcp_checkpoint( std::string file_name __attribute__((unused))) {
#ifdef _DMTCP
    SIM_MODE sim_mode ;
    sim_mode = exec_get_mode() ;

    setDMTCPFilename( file_name );
    dmtcp_set_checkpoint_now();

    //fix for what I believe is a dmtcp bug: --DANNY
    //      When you do a dmtcp_checkpoint from sim control panel (in freeze), the var server calls parse()
    //      in the input processor which calls this function -- IPParse locks ip_mutex before
    //      the parse call and unlocks it after the parse call. BUT if you call_dmtcp right now
    //      the checkpoint can occur while ip_mutex is still locked. When you do a dmtcp restart,
    //      the sim hangs because it cannot unlock ip_mutex (dmtcp claims to handle mutexes, doh!).
    //      SO, don't do call_dmtcp here in freeze, it will be called in the dmtcp freeze job. This "fixes"
    //      the problem, although the var server is a thread so we're technically still vulnerable.
    if ((sim_mode != Initialization) && (sim_mode != Freeze))
        call_dmtcp();
#endif
    return 0;
}

int Trick::CheckPointRestart::dmtcp_checkpoint( double in_time __attribute__((unused))) {
#ifdef _DMTCP
    long long curr_time = exec_get_time_tics() ;
    long long new_time = (long long)(in_time * exec_get_time_tic_value()) ;

    if ( new_time >= curr_time )
        dmtcp_checkpoint_times.push( new_time ) ;
#endif
    return 0 ;
}

int Trick::CheckPointRestart::write_dmtcp_checkpoint() {
#ifdef _DMTCP

    long long curr_time = exec_get_time_tics() ;

    if ( (!dmtcp_checkpoint_times.empty() )  and (curr_time == dmtcp_checkpoint_times.top()) ) {

        dmtcp_checkpoint();

        while ( !dmtcp_checkpoint_times.empty() and (dmtcp_checkpoint_times.top() == curr_time) )
            dmtcp_checkpoint_times.pop() ;
    }

    if ( (dmtcp_safestore_enabled)  && (curr_time == dmtcp_safestore_time) ){

        dmtcp_checkpoint("dmtcp_chkpnt_safestore");
        dmtcp_safestore_time += dmtcp_safestore_period ;
    }

#endif
    return 0;
}

int Trick::CheckPointRestart::write_pre_init_checkpoint() {
    if ( pre_init_checkpoint ) {
        checkpoint(std::string("chkpnt_pre_init")) ;
    }
    return 0  ;
}

int Trick::CheckPointRestart::write_post_init_checkpoint() {
    if ( post_init_checkpoint ) {
        checkpoint(std::string("chkpnt_post_init")) ;
    }
    return 0  ;
}

int Trick::CheckPointRestart::write_end_checkpoint() {
    if ( end_checkpoint ) {
        checkpoint(std::string("chkpnt_end")) ;
    }
    return 0  ;
}

int Trick::CheckPointRestart::safestore_checkpoint() {

    if ( safestore_enabled) {
        checkpoint(std::string("chkpnt_safestore"), false) ;
        safestore_time += safestore_period ;
    }

    if ( safestore_checkpoint_job != NULL ) {
        safestore_checkpoint_job->next_tics = safestore_time ;
    }

    return(0) ;
}

void Trick::CheckPointRestart::load_checkpoint(std::string file_name) {
    load_checkpoint_file_name = file_name ;
}

int Trick::CheckPointRestart::load_checkpoint_job() {

    JobData * curr_job ;
    struct stat temp_buf ;

    if ( ! load_checkpoint_file_name.empty() ) {

        if ( stat( load_checkpoint_file_name.c_str() , &temp_buf) == 0 ) {
            preload_checkpoint_queue.reset_curr_index() ;
            while ( (curr_job = preload_checkpoint_queue.get_next_job()) != NULL ) {
                curr_job->call() ;
            }

            // clear the queues!  They will be rebuilt when the executive calls its restart job.
            checkpoint_queue.clear() ;
            post_checkpoint_queue.clear() ;
            preload_checkpoint_queue.clear() ;
            restart_queue.clear() ;

            message_publish(MSG_INFO, "Load checkpoint file %s.\n", load_checkpoint_file_name.c_str()) ;
            trick_MM->init_from_checkpoint(load_checkpoint_file_name.c_str()) ;

            message_publish(MSG_INFO, "Finished loading checkpoint file.  Calling restart jobs.\n") ;

            // bootstrap the sim_objects back into the executive!
            // TODO: MAKE AN exec_restart() CALL THAT DOES NOT REQUIRE WE USE the_exec.
            the_exec->restart() ;

            // the restart queue will be rebuilt by the executive.
            restart_queue.reset_curr_index() ;
            while ( (curr_job = restart_queue.get_next_job()) != NULL ) {
                curr_job->call() ;
            }
        } else {
            message_publish(MSG_INFO, "Could not find checkpoint file %s.\n", load_checkpoint_file_name.c_str()) ;
        }
        load_checkpoint_file_name.clear() ;
    }

    return(0) ;
}

int Trick::CheckPointRestart::load_default_data() {

    trick_MM->read_checkpoint("S_default.dat") ;
    return(0) ;
}

int Trick::CheckPointRestart::write_s_job_execution(FILE *fp) {

    if ( fp == NULL ) {
        return(0) ;
    }

    fprintf(fp, "\n===================================================================================================\n") ;
    fprintf(fp, "CheckPointRestart :\n\n") ;
    checkpoint_queue.write_non_sched_queue(fp) ;
    post_checkpoint_queue.write_non_sched_queue(fp) ;
    preload_checkpoint_queue.write_non_sched_queue(fp) ;
    restart_queue.write_non_sched_queue(fp) ;
    return 0 ;
}

int Trick::CheckPointRestart::instrument_job_before( Trick::JobData * instrument_job ) {

    int count = 0 ;

    /** @par Detailed Design: */

    /** @li if target_job specified, instrument job will only be inserted before it
        note: when more than one target job with same name, this will insert instrument job for 1st occurrence of target_job in each queue
     */
    count += checkpoint_queue.instrument_before(instrument_job) ;
    count += preload_checkpoint_queue.instrument_before(instrument_job) ;
    count += restart_queue.instrument_before(instrument_job) ;

    /** @li Return how many insertions were done. */
    return(count) ;

}

int Trick::CheckPointRestart::instrument_job_after( Trick::JobData * instrument_job ) {

    int count = 0 ;

    /** @par Detailed Design */
    // if target_job specified, instrument job will only be inserted after it
    // note: when more than one target job with same name, this will insert instrument job for 1st occurrence of target_job in each queue

    count += checkpoint_queue.instrument_after(instrument_job) ;
    count += preload_checkpoint_queue.instrument_after(instrument_job) ;
    count += restart_queue.instrument_after(instrument_job) ;

    /** @li Return how many insertions were done. */
    return(count) ;

}

int Trick::CheckPointRestart::instrument_job_remove(std::string in_job) {

    checkpoint_queue.instrument_remove(in_job) ;
    preload_checkpoint_queue.instrument_remove(in_job) ;
    restart_queue.instrument_remove(in_job) ;

    return(0) ;
}