}

/**

   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

*/

void prepare_distrenjob(struct frameset *head, int type, char *name, char *submitter, char *email, int priority, int start_frame, int end_frame)

{

  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)

{

  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");

      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;

  else

    {

      for(previous_distrenjob = *head;

        previous_distrenjob

          && previous_distrenjob->next != bj; /*< stop on the distrenjob that comes before bj */

          previous_distrenjob = previous_distrenjob->next)

	/* all of the action is in the definition of the for loop itself */;

      /*

	This removes references to bj from the linked list. I.E., we now skip bj when iterating through the list

       */

      previous_distrenjob->next = bj->next;

    }

  general_info.jobs_in_queue--;

}

/* Grabs config info from confs */

int distrend_do_config(int argc, char *argv[], struct distrend_config **config)

{

  cfg_opt_t myopts_listen[] =

    {

      CFG_SIMPLE_STR("type", NULL),

      CFG_SIMPLE_STR("path", NULL),

      CFG_SIMPLE_INT("port", NULL),

      CFG_END()

    };

  cfg_opt_t myopts[] =

    {

      CFG_SEC("listen",  /* this must be imported into struct listens (which must still be declared) */

          myopts_listen,

          CFGF_MULTI),

      CFG_SIMPLE_STR("datadir", NULL),

      CFG_END()

    };

  struct distrenjob *distrenjob;

  int tmp;

  xmlinit();

  /*

   * test xml2distrenjob()

   */

  tmp = xml2distrenjob(&distrenjob, "distrenjob.xml.example");

  if(tmp)

    fprintf(stderr, "xml2distrenjob() returned %d. Try to cd to distren/doc if you want to test out the xml2distrenjob() function. (This will only fix this error if the error is due to an inability of the xml library to access distrenjob.xml.example)\n", tmp);

  else

    fprintf(stderr, "using email ``%s'' for user ``%s'' -- reading in XML files and pulling data from them using libxml2+XPath works!!!\n", distrenjob->email, distrenjob->submitter);

  fprintf(stderr, "%s:%d running config\n", __FILE__, __LINE__);

  *config = malloc(sizeof(struct distrend_config));

  myopts[1].simple_value = &(*config)->datadir;

  options_init(argc, argv, &(*config)->mycfg, myopts, "server", &(*config)->options);

  fprintf(stderr, "using %s as datadir\n", (*config)->datadir);

  xmlcleanup();

  return 0;

}

int distrend_config_free(struct distrend_config *config)

{

  options_free(config->options);

  free(config);

  return 0;

}

/* ************************** Main ************************* */

int main(int argc, char *argv[])

{

  /* @TODO: Put some arg-grabbing code here */

  struct distrenjob head;

  head.priority = 0; // make head have the highest priority

  int cont;

  struct distrend_listenset *listenset;

  struct distrend_config *config;

  enum clientstatus

  {

    CLIENTSTATUS_UNINITIALIZED = 0,

    CLIENTSTATUS_BUSY = 1,

    CLIENTSTATUS_IDLE = 2

  } clientstatus;

  cont = 1;

  memset(&head, '\0', sizeof(struct distrenjob));

  start_data(); // Starts fresh or loads data from xml dump. Should we grab the return?

  distrend_do_config(argc, argv, &config);

  distrend_listen(&listenset, config);

  /* This is called the "main loop" */

  while(cont)

    {

      struct distren_action *action;

      int clientsays; /*< temporary example variable, will be replaced when we can handle messages */

      distrend_accept(&action);

      cont = distrend_do(action);

      /* Make the following code more event-driven */

      blend_frame_watchdog(&head);

      struct frameset *frame;

      struct distrenjob *job;

      /* If the client is idle, must be modified for climbing through linked list of clients (client->clientnum) */

      if(clientstatus == CLIENTSTATUS_IDLE)

	{

	  int returnnum = find_jobframe(&head, &job, &frame); // Finds a frame to render

	  if(returnnum)

	    {

	      fprintf(stderr,"No frames are available to render at this time. Idling...\n");

	      sleep(10);

	    }

	  else

	    /* returnnum == 0 */

	    remotio_send_to_client(frame->num, job->jobnum); // Pseudo-sends data to client

	}