/*

  Copyright 2009 Nathan Phillip Brink, Ethan Zonca, Matthew Orlando

  This file is a part of DistRen.

  DistRen is free software: you can redistribute it and/or modify

  it under the terms of the GNU Affero General Public License as published by

  the Free Software Foundation, either version 3 of the License, or

  (at your option) any later version.

  DistRen is distributed in the hope that it will be useful,

  but WITHOUT ANY WARRANTY; without even the implied warranty of

  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  GNU Affero General Public License for more details.

  You should have received a copy of the GNU Affero General Public License

  along with DistRen.  If not, see <http://www.gnu.org/licenses/>.

*/

/* This file contains the code which both processes (renders) jobs as a slave, and the code which distributes frames to slaves after receiving them from the client portion of the codebase. */

#include "execio.h"

#include "options.h"

#include "distrenjob.h"

#include "protocol.h"

#include "slavefuncs.h"

#include <confuse.h>

#include <stdio.h>

#include <stdlib.h>

#include <malloc.h>

#include <unistd.h> /* getopt */

#include <time.h>

#include <sys/stat.h>

/* ******************* Structs ************************ */

// Gets config info from confs

struct distrend_config

{

  cfg_t *mycfg;

  struct options_common *options;

  struct distrend_listen **listens; /*< Null terminated array of structs */

  char *datadir;

};

struct general_info {

  short int jobs_in_queue; //

  unsigned short int free_clients;

  unsigned short int rendering_clients;//

  unsigned short int total_finished_jobs; //

  unsigned int total_frames_rendered; //

  unsigned int highest_jobnum;

} general_info;

/*

  internally defined funcs's prototypes

*/

void distrenjob_remove(struct distrenjob **head, struct distrenjob *bj);

struct distrenjob *distrenjob_get(struct distrenjob *head, jobnum_t jobnum);

void distrenjob_enqueue(struct distrenjob *head, struct distrenjob *job);

void mortition(struct distrenjob *head, struct distrenjob *job);

/* Global Vars, try to cut down on these */

jobnum_t jobnum = 0; // The next job number to create in the queue

int hcfjob; // Highest consecutively finished job

int highest_jobnum; // The job number of the most recently created job, this is used when creating new jobs

/* ********************** Functions ************************* */

/** Dumps all data in RAM to an xml file (such as current jobs, etc) which is parsed by start_data. Remember to invoke this before shutting down! */

int xml_dump()

{

  return 0;

}

/**

   Performs command stored in a client's request.

*/

int distrend_do()

{

  return 0;

}

/**

   Accepts a client's connection

 */

void distrend_accept()

{

}

/**

   Frees the action

*/

void distrend_action_free()

{

}

/**

   Start listening

*/

void distrend_listen()

{

}

/**

   Stop listening

*/

void distrend_unlisten()

{

}

/**

   This is probably just a placeholder for remotio

*/

void remotio_send_to_client()

{

	// I am futile!

}

/** Fill variables after crash / shutdown from XML dumps */

int start_data(){

  struct stat buffer;

  if(stat(SYSCONFDIR "/data.xml", &buffer) == 0){

    // @TODO: retrieve total_finished_jobs and total_finished_frames from xml file

    fprintf(stderr,"Parsing XML files and restoring previous state...\n");

    return 1;

  }

  else{

    general_info.total_finished_jobs = 0;

    general_info.total_frames_rendered = 0;

    fprintf(stderr,"Can't find XML dump, starting up fresh.\n");

    return 2;

  }

  free(&buffer); // @TODO: Is this pointless?

}

/** Finish-Setter: Sets a frame to the "completed" status.*/

void finish_frame(struct distrenjob *head, struct distrenjob *distrenjob, int frame){

  distrenjob->frameset[frame].status = FRAMESETSTATUS_DONE;

  distrenjob->frameset[frame].time_to_render = (clock() - distrenjob[jobnum].frameset[frame].start_time); // Consider changing time-to-render to time-for-frame or something?

  /* TODO: calculating the average render time like this may have a small amount of error, because the number is truncated to an integer of seconds every time... does it matter? */

  /* we could keep track of the total render time... would make calculation a lot easier and more accurate */

  distrenjob->avg_render_time = ((distrenjob->avg_render_time*(distrenjob->completed_frames)) + distrenjob->frameset[frame].time_to_render)/(distrenjob->completed_frames + 1);

  distrenjob->completed_frames++;

  distrenjob->assigned_frames--;

  general_info.total_frames_rendered++; // Increase total frames var for stats

  if(distrenjob->completed_frames == distrenjob->total_frames)

    {

      mortition(head, distrenjob);

    }

}

/** mortition check to see if a job is actually done by scanning the folder of the job to make sure all frames are present*/

// called mortition because it checks the finished "dead" job

void mortition(struct distrenjob *head, struct distrenjob *job){

  short int isJobDone;

  int counter;

  char path_and_number[20];

  struct stat buffer;

  isJobDone = 1; // set isJobDone to true

  for(counter = 0; counter < job->total_frames; counter++)

    {

      sprintf(path_and_number, "stor/job%d/out/%d.%s", job->jobnum, (counter + job->frameset[0].num), job->output_format);

      if(stat(path_and_number, &buffer) != -1)

        {

          job->frameset[counter].status = FRAMESETSTATUS_UNASSIGNED;

          job->completed_frames--;

          isJobDone = 0; // if a missing frame is found, set isJobDone to false

        }

    }

  if(isJobDone)

    {

      distrenjob_remove(&head, job);

      general_info.jobs_in_queue--;

    }

}

/**

   creates a structure from starting data, then calls another function to actually add that struct to the queue

*/

{

  int counter2;

  int counter;

  struct distrenjob *distrenjob;

  distrenjob->type = 1;

  distrenjob->name = name;

  distrenjob->submitter = submitter;

  distrenjob->email = email;

  distrenjob->priority = priority;

  distrenjob->total_frames = (end_frame - start_frame + 1); // sets the total number of frames in animation for status purposes

  distrenjob->frameset = malloc(distrenjob->total_frames);

  distrenjob->assigned_frames = 0;

  distrenjob->completed_frames = 0;

  /* @TODO: should the aove be malloc(sizeof(struct frameset) * distrenjob->total_frames? */

  /*

  distrenjob->frameset = malloc(sizeof(struct frameset) * numframes);

  if(!job->frameset)

    fprintf(stderr, "Error allocating memory\n");

  */

  /* prepares all the frames by setting that status to "unassigned" */

  counter2 = start_frame;

  for(counter = 0; counter <= (end_frame- start_frame + 1); counter++){

    distrenjob->frameset[counter].num = counter2;

    distrenjob->frameset[counter].status = FRAMESETSTATUS_UNASSIGNED;

    counter2++;

  }

  distrenjob_enqueue(head, distrenjob);

  general_info.jobs_in_queue++;

}

/* distrenjob_enqueue: This function adds the job to the queue based on its priority */

void distrenjob_enqueue(struct distrenjob *head, struct distrenjob *job) {

  struct distrenjob *prev_job = head; // create pointer to previous job

  struct distrenjob *current_job;     // create pointer to current_job (which job is being compared to)

  // iterate through linked list of jobs

  for(current_job = head; current_job != NULL; current_job = current_job->next){

    if(current_job == NULL){ // if it has reached the end of the list, add job there

      current_job = job;

      break;

    }

    else if(job->priority < current_job->priority){ // if job's priority is less than current_job's priority, insert job

      prev_job->next = job;                        // keep in mind 1 is the highest priority given to jobs, head has a

      job->next = current_job;                     // priority of zero so it will always be before other jobs

      break;

    }

    prev_job = current_job;

  } /* for(current_job) */

}

/**

   @arg head I may end up changing the head if job == head

 */

void change_job_priority(struct distrenjob *head, struct distrenjob *job, int new_priority){

  distrenjob_remove(&head, job);

  job->priority = new_priority;

  struct distrenjob *current_job;

  struct distrenjob *prev_job = head;

  if(job->frameset[0].status == FRAMESETSTATUS_UNASSIGNED)

    /* if job was not yet started */

    distrenjob_enqueue(head, job);

  else{ // if job has already been started then place it before the jobs with the same priority

    // iterate through linked list of jobs

    for(current_job = head; current_job != NULL; current_job = current_job->next){

      if(current_job == NULL){ // if it has reached the end of the list, add job there

        current_job = job;

        break;

      }

      else if(job->priority <= current_job->priority){ // if job's priority is less than or equal to current_job's priority, insert job

        prev_job->next = job;                        // keep in mind 1 is the highest priority given to jobs, head has a

        job->next = current_job;                     // priority of zero so it will always be before other jobs

        break;

      }

      prev_job = current_job;

    }

  }

}

/**

  Frame Finder: matches your computer up with a lovely frame to render

  TODO: Major issue here, the client needs to know the frame number, AND the job number!

  Notice that this function starts by looking at the oldest job first

	TODO: Link this up with the main() function to check if there are frames available or not and provide jobnum/framenum to the client

  @return 0 success, other: error

*/

int find_jobframe(struct distrenjob *head, struct distrenjob **job, struct frameset **frame)

{

  unsigned int frame_counter;

  short int your_job_type;

  unsigned short int found;

  struct distrenjob *distrenjob_ptr;

  your_job_type = 0;

  found = 0;

  /* iterate through jobs from first to last */

  for(distrenjob_ptr = head->next; !found && !distrenjob_ptr; distrenjob_ptr = distrenjob_ptr->next)

    for(frame_counter = 0; !found && frame_counter < distrenjob_ptr->total_frames; frame_counter ++)

      if(distrenjob_ptr->frameset[frame_counter].status == FRAMESETSTATUS_UNASSIGNED)

	{

	  found = 1;

	  your_job_type = distrenjob_ptr->type;

	  distrenjob_ptr->frameset[frame_counter].status = FRAMESETSTATUS_ASSIGNED;

	  distrenjob_ptr->frameset[frame_counter].start_time = clock();

	  distrenjob_ptr->assigned_frames++;

	}

  if(!found)

    {

      fprintf(stderr, "No more jobs to render\n");

      sleep(1); /*< @todo eliminate the need for this line*/

      return 1;

    }

  *job = distrenjob_ptr;

  *frame = &distrenjob_ptr->frameset[frame_counter];

  return 0;

}

/** Checks for dead, laggy, or stale slaves */

void blend_frame_watchdog(struct distrenjob *distrenjob_head)

{

  unsigned short int watchdog_forgiveness; /*< seconds to wait on a frame before re-assigning it */

  struct distrenjob *distrenjob_ptr;

  unsigned int counter;

  watchdog_forgiveness = 1; /*< hours of forgiveness before frame is re-assigned @TODO: Make this more user-configurable (maybe per-job), 3 hours is a LONG time */

  distrenjob_ptr = distrenjob_head;

  for(distrenjob_ptr = distrenjob_head; distrenjob_ptr; distrenjob_ptr = distrenjob_ptr->next)

    /* iterate through jobs */

    for(counter = 0; counter < distrenjob_ptr->total_frames; counter ++)

      /* iterate through all frames for this job*/

      {

        if((distrenjob_ptr->frameset[counter].start_time + (watchdog_forgiveness * 3600)) < clock())

          /*

            If frame is not completed within the number of hours specified by watchdog_forgiveness

            Then change the frame status to unassigned

           */

          distrenjob_ptr->frameset[counter].status = FRAMESETSTATUS_UNASSIGNED;

      }

}

/**

   Finds a distrenjob struct based on the jobnum

   @arg jobnum job number to search for

   @return NULL on job doesn't exist

 */

struct distrenjob *distrenjob_get(struct distrenjob *head, jobnum_t jobnum)

{

  struct distrenjob *distrenjob_ptr;

  /*

    The conditions of the for loop will leave distrenjob_ptr at NULL if the end of the list is reached. It will leave it pointing to the correct job if it is found.

   */

  for(distrenjob_ptr = head;

      distrenjob_ptr

        && distrenjob_ptr->jobnum != jobnum;

      distrenjob_ptr = distrenjob_ptr->next);

  return distrenjob_ptr;

}

/**

   Removes a distrenjob from the distrenjob linked list.

   @arg head a double pointer. the head pointer will have to be changed if distrenjob == *head. Thus, make sure that the pointer points to the pointer to the head that all functions use. (I'm going to come back to this and misunderstand myself ;-))

 */

void distrenjob_remove(struct distrenjob **head, struct distrenjob *bj)

{

  struct distrenjob *previous_distrenjob;

  if(bj == *head)

    *head = bj->next;