/*
  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. */

/*
  To get getline():
 */
#define _GNU_SOURCE 1

#include "execio.h"
#include "options.h"
#include "distrenjob.h"
#include "protocol.h"
#include "slavefuncs.h"
#include "asprintf.h"

#include <confuse.h>
#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#include <unistd.h> /* getopt */
#include <time.h>
#include <sys/stat.h>
#include <string.h>

#include <libxml/xmlmemory.h>
#include <libxml/parser.h>
#include <libxml/tree.h>
#include <libxml/encoding.h>
#include <libxml/xmlwriter.h>
#include <libxml/xmlreader.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;
  short int hibernate;
} general_info;



/*
  internally defined funcs's prototypes @TODO: Make all functions nice and proper */
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);
int makeJobDataXML(struct distrenjob *job);
int updateJobListXML(struct distrenjob *head);
int createQueueFromXML(struct distrenjob *head);
int reCreateQueueFromXML(struct distrenjob *head, xmlDocPtr doc, xmlNodePtr current);
void updateGeneralInfo();
void importGeneralInfo();
int updateJobStatsXML(struct distrenjob *job);


/* Global Vars, eliminate 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 distrenjob *head)
{
  struct stat buffer;
  if(stat("general_info.xml", &buffer) == 0){
    importGeneralInfo();

    fprintf(stderr,"Parsing XML files and restoring previous state...\n");
    createQueueFromXML(head);
    return 1;
  }
  else{
    general_info.total_finished_jobs = 0;
    general_info.total_frames_rendered = 0;
    general_info.free_clients = 0;
    general_info.highest_jobnum = 0;
    general_info.jobs_in_queue = 0;
    general_info.rendering_clients = 0;
    general_info.hibernate = 0;
    fprintf(stderr,"Couldn't find XML dump, starting up fresh.\n");
    return 2;
  }
}

/** 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->total_render_time = distrenjob->total_render_time + (clock() - distrenjob[jobnum].frameset[frame].start_time);
  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);
    }

  updateGeneralInfo();
  updateJobStatsXML(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*/
void mortition(struct distrenjob *head, struct distrenjob *job)
{
  short int isJobDone;
  int counter;
  char *path_and_number;
  struct stat buffer;

  isJobDone = 1; // set isJobDone to true
  for(counter = 0; counter < job->total_frames; counter++)
    {
      _distren_asprintf(&path_and_number, "stor/job%d/out/%d.%s", job->jobnum, job->frameset[counter].num, job->output_format);
      if(stat(path_and_number, &buffer) == -1)
        {
          job->frameset[counter].status = FRAMESETSTATUS_UNASSIGNED;
          job->completed_frames--;
          general_info.total_frames_rendered--;
          isJobDone = 0; // if a missing frame is found, set isJobDone to false
        }
    }

  if(isJobDone) // if all frames were accounted for
    {
      distrenjob_remove(head, job);
      distrenjob_free(&job);
      general_info.jobs_in_queue--;
      updateJobListXML(head);
    }
  else{
    job->prev_frame_index = 0; // if the job isn't done, have frame_finder() start from the first frame, allowing it to see the frames that are now unassigned
  }

  updateGeneralInfo();
}

/** scans the frames of a job to initialize a job after server */
/* returns 1 if the job is completely done and there are no missing frames */
/* returns 0 if a missing frame is found */
int restoreJobState(struct distrenjob *job)
{
  short int isJobDone;
  int counter;
  char *path_and_number;
  struct stat buffer;

  isJobDone = 1;
  for(counter = 0; counter < job->total_frames; counter++)
    {
      _distren_asprintf(&path_and_number, "stor/job%d/out/%d.%s", job->jobnum, job->frameset[counter].num, job->output_format);
      if(stat(path_and_number, &buffer) == 0)
        {
          job->frameset[counter].status = FRAMESETSTATUS_ASSIGNED;
          job->completed_frames++;
        }
      else
        isJobDone = 0;
    }

  return isJobDone;
}

/** creates a structure from starting data, then calls another function to actually add that struct to the queue */
int prepare_distrenjob(struct distrenjob *head, int type, char *name, char *submitter, char *email, int priority, int start_frame, int end_frame, int width, int height)
{
  int counter2;
  int counter;
  int tmp;
  char *path_with_num;

  struct distrenjob *distrenjob;
  tmp = distrenjob_new(&distrenjob);
  if(tmp)
    return 1;

  general_info.highest_jobnum++;

  distrenjob->jobnum = general_info.highest_jobnum;
  distrenjob->type = 1;
  distrenjob->name = name;
  distrenjob->submitter = submitter;
  distrenjob->email = email;
  distrenjob->priority = priority;
  distrenjob->width = width;
  distrenjob->height = height;
  distrenjob->total_frames = (end_frame - start_frame + 1); /* sets the total number of frames in animation for status purposes */
  distrenjob->frameset = malloc(sizeof(struct frameset) * distrenjob->total_frames);
  if(!distrenjob->frameset)
    {
      distrenjob_free(&distrenjob);
      return 1;
    }

  /* prepares all the frames by setting that status to "unassigned" */
  counter2 = start_frame;
  for(counter = 0; counter < distrenjob->total_frames; counter++){
    distrenjob->frameset[counter].num = counter2;
    distrenjob->frameset[counter].status = FRAMESETSTATUS_UNASSIGNED;

    counter2++;
  }

  _distren_asprintf(&path_with_num, "stor/job%d/out/", distrenjob->jobnum);
  fprintf(stderr, "creating dir '%s'", path_with_num);

  /* add job to queue */
  fprintf(stderr, "\nprepare_distrenjob: attempting makeJobDataXML()\n");
  makeJobDataXML(distrenjob);
  fprintf(stderr, "\nprepare_distrenjob: attempting distrenjob_enqueue()\n");
  distrenjob_enqueue(head, distrenjob);

  general_info.jobs_in_queue++;
  fprintf(stderr, "\nprepare_distrenjob: attempting updateJobListXML()\n");
  updateJobListXML(head);
  fprintf(stderr, "\nprepare_distrenjob: attempting updateGeneralInfo()\n");
  updateGeneralInfo();
  fprintf(stderr, "\nprepare_distrenjob: attempting updateJobStatsXML()\n");
  updateJobStatsXML(distrenjob);

  return 0;
}


/** 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->next; 1; current_job = current_job->next){
    if(current_job == NULL){ // if it has reached the end of the list, add job there
      prev_job->next = 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) */
}

/** Changes the priority of an existing (and maybe running) 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, 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;
    }
  }
  updateJobListXML(head);
  makeJobDataXML(job); // because priority is changed
}

/**
  Frame Finder: matches your computer up with a lovely frame to render, starts looking at oldest job first
  @TODO: We must return both jobnum and framenum
  @TODO: Add calls in main()
  @return 0 success, other: error
*/
int find_jobframe(struct distrenjob *head, struct distrenjob **job, struct frameset **frame)
{
  if(general_info.hibernate)
    return 1;

  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->hibernate; distrenjob_ptr = distrenjob_ptr->next)
    for(frame_counter = (distrenjob_ptr->prev_frame_index + 1); !found && frame_counter < distrenjob_ptr->total_frames; frame_counter ++)
      if(distrenjob_ptr->frameset[frame_counter].status == FRAMESETSTATUS_UNASSIGNED) // jobframe found
	{
	  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++;
	  distrenjob_ptr->prev_frame_index = frame_counter;
	  updateJobStatsXML(distrenjob_ptr);
	}

  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, latent, or stale slaves */
void frame_watchdog(struct distrenjob *distrenjob_head)
{
  struct distrenjob *distrenjob_ptr;
  unsigned int counter;

  for(distrenjob_ptr = distrenjob_head->next; distrenjob_ptr; distrenjob_ptr = distrenjob_ptr->next)
  /* iterate through jobs */
  {
    /* if the job has been started, checks by seeing if either to first or second frame has been started */
    if(distrenjob_ptr->frameset[0].status != FRAMESETSTATUS_UNASSIGNED || distrenjob_ptr->frameset[1].status != FRAMESETSTATUS_UNASSIGNED)
      /* iterate through all frames for this job: */
      for(counter = 0; counter < distrenjob_ptr->total_frames; counter ++)
	    /*watchdog_forgiveness = seconds of forgiveness before frame is re-assigned: */
        if((distrenjob_ptr->frameset[counter].start_time + distrenjob_ptr->watchdog_forgiveness) < clock())
        {
            /*
            If frame is not completed within the number of seconds specified by watchdog_forgiveness
            Then change the frame status to unassigned
            */
            distrenjob_ptr->frameset[counter].status = FRAMESETSTATUS_UNASSIGNED;
            distrenjob_ptr->assigned_frames--;
        }

    updateJobStatsXML(distrenjob_ptr);
  }
}

/**
   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. It does not free the distrenjob, however. You should do that with distrenjob_free() from distrenjob.h

   @arg head pointer to the head of the linkedlist of distrenjobs
 */
void distrenjob_remove(struct distrenjob *head, struct distrenjob *bj)
{
  struct distrenjob *previous_distrenjob;

  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;

  /*
   * 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\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, "daemon", &(*config)->options);

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

  return 0;
}
int distrend_config_free(struct distrend_config *config)
{
  options_free(config->options);
  free(config);

  return 0;
}
/* ************************** XML Functions ************************* */

// writes the general_info.xml file which is a copy of the general_info structure
// except that it doesn't hold free_clients and rendering_clients
void updateGeneralInfo()
{
  xmlTextWriterPtr writer;
  char *tmp;

  writer = xmlNewTextWriterFilename("general_info.xml", 0);
  xmlTextWriterStartDocument(writer, NULL, "utf-8", NULL);

  xmlTextWriterStartElement(writer, (xmlChar*)"general_info");

  _distren_asprintf(&tmp, "%d", general_info.jobs_in_queue);
  xmlTextWriterWriteElement(writer, (xmlChar*)"jobs_in_queue", (xmlChar*)tmp);
  _distren_asprintf(&tmp, "%d", general_info.total_finished_jobs);
  xmlTextWriterWriteElement(writer, (xmlChar*)"total_finished_jobs", (xmlChar*)tmp);
  _distren_asprintf(&tmp, "%d", general_info.total_frames_rendered);
  xmlTextWriterWriteElement(writer, (xmlChar*)"total_frames_rendered", (xmlChar*)tmp);
  _distren_asprintf(&tmp, "%d", general_info.highest_jobnum);
  xmlTextWriterWriteElement(writer, (xmlChar*)"highest_jobnum", (xmlChar*)tmp);

  xmlTextWriterEndDocument(writer);
  xmlFreeTextWriter(writer);
}

// this reads the information from general_info.xml to the general_info structure
void importGeneralInfo()
{
  xmlDocPtr doc;
  xmlNodePtr cur;

  doc = xmlParseFile("general_info.xml");
  cur = xmlDocGetRootElement(doc);
  if (xmlStrcmp(cur->name, (xmlChar*)"general_info"))
    {
      fprintf(stderr, "xml document is wrong type");
      xmlFreeDoc(doc);
      return;
    }

  cur = cur->xmlChildrenNode;
  general_info.jobs_in_queue = atoi((char*)xmlNodeListGetString(doc, cur->xmlChildrenNode, 1));
  cur = cur->next;
  general_info.total_finished_jobs = atoi((char*)xmlNodeListGetString(doc, cur->xmlChildrenNode, 1));
  cur = cur->next;
  general_info.total_frames_rendered = atoi((char*)xmlNodeListGetString(doc, cur->xmlChildrenNode, 1));
  cur = cur->next;
  general_info.highest_jobnum = atoi((char*)xmlNodeListGetString(doc, cur->xmlChildrenNode, 1));

  general_info.hibernate = 0;
  general_info.free_clients = 0;
  general_info.rendering_clients = 0;

  xmlFreeDoc(doc);
}

// returns 1 on successful completion of xml file
// creates the xml file that slaves read from, and is used to restart distren
int makeJobDataXML(struct distrenjob *job)
{
  xmlTextWriterPtr writer;
  char *tmp; // temporarily holds strings to be given to the xml writer

  _distren_asprintf(&tmp, "stor/job%d/job_info.xml", job->jobnum);

  // create xml document at the location tmp with no compression
  writer = xmlNewTextWriterFilename(tmp, 0);
  xmlTextWriterStartDocument(writer, NULL, "utf-8", NULL);

  // write distrenjob element and add its attributes
  xmlTextWriterStartElement(writer, (xmlChar*)"job");
  xmlTextWriterWriteAttribute(writer, (xmlChar*)"name", (xmlChar*)job->name);
  xmlTextWriterWriteAttribute(writer, (xmlChar*)"submitter", (xmlChar*)job->submitter);
  _distren_asprintf(&tmp, "%d", job->priority);
  xmlTextWriterWriteAttribute(writer, (xmlChar*)"priority", (xmlChar*)tmp);

  // write resolution element and add its attributes
  xmlTextWriterStartElement(writer, (xmlChar*)"resolution");
  _distren_asprintf(&tmp, "%d", job->width);
  xmlTextWriterWriteAttribute(writer, (xmlChar*)"width", (xmlChar*)tmp);
  _distren_asprintf(&tmp, "%d", job->height);
  xmlTextWriterWriteAttribute(writer, (xmlChar*)"height", (xmlChar*)tmp);
  xmlTextWriterEndElement(writer);

  // write video element and its attributes
  xmlTextWriterStartElement(writer, (xmlChar*)"video");
  _distren_asprintf(&tmp, "%d", job->frameset[0].num);
  xmlTextWriterWriteAttribute(writer, (xmlChar*)"start_frame", (xmlChar*)tmp);
  _distren_asprintf(&tmp, "%d", job->frameset[(job->total_frames - 1)].num);
  xmlTextWriterWriteAttribute(writer, (xmlChar*)"end_fame", (xmlChar*)tmp);
  xmlTextWriterWriteAttribute(writer, (xmlChar*)"output_format", (xmlChar*)job->output_format);
  xmlTextWriterEndElement(writer);

  // write watchdog forgiveness element
  _distren_asprintf(&tmp, "%d", job->watchdog_forgiveness);
  xmlTextWriterWriteElement(writer, (xmlChar*)"wd_forgiveness", (xmlChar*)tmp);

  // end document
  xmlTextWriterEndDocument(writer);

  // free writer and save xml file to disk
  xmlFreeTextWriter(writer);

  return 1;
}

// extracts data from the xml created by above function and creates a job from it
// it returns a pointer to the created job
struct distrenjob *createJobFromXML(int job_number)
{
  xmlDocPtr doc;
  xmlNodePtr cur;
  char *file_name;
  struct distrenjob *distrenjob;
  int start_frame;
  int counter;
  int counter2;

  distrenjob_new(&distrenjob);

  _distren_asprintf(&file_name, "stor/job%d/job_info.xml", job_number);

  doc = xmlParseFile(file_name);
  cur = xmlDocGetRootElement(doc);

  distrenjob->name = (char*)xmlGetProp(cur, (xmlChar*)"name");
  distrenjob->submitter = (char*)xmlGetProp(cur, (xmlChar*)"submitter");
  distrenjob->priority = atoi((char*)xmlGetProp(cur, (xmlChar*)"priority"));

  cur = cur->xmlChildrenNode;
  distrenjob->width = atoi((char*)xmlGetProp(cur, (xmlChar*)"width"));
  distrenjob->height = atoi((char*)xmlGetProp(cur, (xmlChar*)"number"));

  cur = cur->next;
  start_frame = atoi((char*)xmlGetProp(cur, (xmlChar*)"start_frame"));
  distrenjob->total_frames = atoi((char*)xmlGetProp(cur, (xmlChar*)"end_frame")) - start_frame + 1;
  distrenjob->output_format = (char*)xmlGetProp(cur, (xmlChar*)"output_format");

  cur = cur->next;
  distrenjob->watchdog_forgiveness = atoi((char*)xmlNodeListGetString(doc, cur->xmlChildrenNode, 1));

  xmlFreeDoc(doc);

  // load up stats.xml file to retrieve data
  _distren_asprintf(&file_name, "stor/job%d/stats.xml", job_number);

  doc = xmlParseFile(file_name);
  cur = xmlDocGetRootElement(doc);

  distrenjob->total_render_time = (time_t)atol((char*)xmlGetProp(cur, (xmlChar*)"total_render_time"));

  xmlFreeDoc(doc);

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

  // change the status of all frames to "unassigned"
  counter2 = start_frame;
  for(counter = 0; counter <= distrenjob->total_frames; counter++){
    distrenjob->frameset[counter].num = counter2;
    distrenjob->frameset[counter].status = FRAMESETSTATUS_UNASSIGNED;

    counter2++;
  }

  restoreJobState(distrenjob);
  return distrenjob;
}

int updateJobStatsXML(struct distrenjob *job)
{
	  xmlTextWriterPtr writer;
	  char *tmp; // temporarily holds strings to be given to the xml writer

	  _distren_asprintf(&tmp, "stor/job%d/stats.xml", job->jobnum);

	  // create xml document at the location tmp with no compression
	  writer = xmlNewTextWriterFilename(tmp, 0);
	  xmlTextWriterStartDocument(writer, NULL, "utf-8", NULL);

	  xmlTextWriterStartElement(writer, (xmlChar*)"stats");
	  _distren_asprintf(&tmp, "%d", job->assigned_frames);
	  xmlTextWriterWriteAttribute(writer, (xmlChar*)"assigned_frames", (xmlChar*)tmp);
	  _distren_asprintf(&tmp, "%d", job->completed_frames);
	  xmlTextWriterWriteAttribute(writer, (xmlChar*)"completed_frames", (xmlChar*)tmp);
	  _distren_asprintf(&tmp, "%d", job->total_render_time);
	  xmlTextWriterWriteAttribute(writer, (xmlChar*)"total_render_time", (xmlChar*)tmp);

	  // end document
	  xmlTextWriterEndDocument(writer);
	  // free writer and save xml file to disk
	  xmlFreeTextWriter(writer);

	  return 1;
}

// returns 1 if successful
// updates job_list.xml which lists all the jobs in the queue
int updateJobListXML(struct distrenjob *head)
{
  struct distrenjob *job;
  xmlTextWriterPtr writer;
  char *tmp;
  char *tmp2;
  int counter;

  writer = xmlNewTextWriterFilename("job_list.xml", 0);
  xmlTextWriterStartDocument(writer, NULL, "utf-8", NULL);

  // create root element job_list
  xmlTextWriterStartElement(writer, (xmlChar*)"job_list");

  _distren_asprintf(&tmp, "%d", general_info.jobs_in_queue);
  xmlTextWriterWriteAttribute(writer, (xmlChar*)"amount", (xmlChar*)tmp);

  counter = 0;
  for(job = head->next; job; job = job->next)
    {
      _distren_asprintf(&tmp, "jobnum%d", counter);
      _distren_asprintf(&tmp2, "%d", job->jobnum);
      xmlTextWriterWriteElement(writer, (xmlChar*)tmp, (xmlChar*)tmp2);
      counter++;
    }

  // close elements and end document
  xmlTextWriterEndDocument(writer);

  // free writer and save xml file to disk
  xmlFreeTextWriter(writer);
  return 1;
}

// returns 1 if completed successfully, 0 if not
// this reads a list of jobs in the queue before DistRen was shut down
// and then adds the jobs to the queue, as if it were never shut down
int createQueueFromXML(struct distrenjob *head)
{
  xmlDocPtr doc;  // holds xml document in memory
  xmlNodePtr cur; // points to the current xml element node

  // load xml document
  doc = xmlParseFile("job_list.xml");
  if(doc == NULL)
    {
      fprintf(stderr, "createQueueFromXML: document not found\n");
      return 0;
    }

  // have cur point to the root element of the xml document pointed to by doc
  cur = xmlDocGetRootElement(doc);
  if(cur == NULL)
    {
      fprintf(stderr, "createQueueFromXML: document empty\n");
      return 0;
    }

  if(xmlStrcmp(cur->name, (const xmlChar*)"job_list"))
    {
      fprintf(stderr, "createQueueFromXML: incorrect root element (%s)", (char*)cur->name);
    }

  // moves into the children elements of job_list
  cur = cur->xmlChildrenNode;

  reCreateQueueFromXML(head, doc, cur);
  /* scans the list of all jobs that were in queue before DistRen shutdown
  while(cur != NULL)
    {
      tmp = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
      fprintf(stderr, "adding job: %s", tmp);
      // add job from job number @TODO create function with parameters (struct distrenjob *head, int job_number)
      // LordOfWar calls dibs on above todo


      xmlFree(tmp);
      cur = cur->next; // go to next child element of job_list element
    }*/

  xmlFreeDoc(doc);

  return 1;
}

// inserts jobs at front of queue, starting with the last job in the job_list xml file
// to preserve the order of the queue
int reCreateQueueFromXML(struct distrenjob *head, xmlDocPtr doc, xmlNodePtr current)
{
  struct distrenjob *holder; // holds the job that "was" after head, so that the new struct can be inserted after head
  struct distrenjob *job; // job to be added
  xmlChar *tmp;
  int job_num;
  if(current == NULL) // base case, if element doesn't exist then don't do anything
    return 0;

  // recursively call itself so that the next job in the queue is added to the front before the current one
  reCreateQueueFromXML(head, doc, current->next);

  // now actual work is done, adding the job to the front of the queue
  holder = head->next; // initialize holder
  tmp = xmlNodeListGetString(doc, current->xmlChildrenNode, 1); // get job number
  job_num = atoi((char*)tmp);
  job = createJobFromXML(job_num);
  xmlFree(tmp); // free xml char (that holds the job number)

  // insert job at front of the queue
  head->next = job;
  job->next = holder;

  return 1;
}

/* ************************** Test Functions ************************* */
void printFrameInfo(struct frameset *frame)
{
  char *status;

  status = NULL;

  switch(frame->status)
  {
    case FRAMESETSTATUS_UNASSIGNED:
      _distren_asprintf(&status, "%s", "unassigned");
      break;
    case FRAMESETSTATUS_ASSIGNED:
      _distren_asprintf(&status, "%s", "assigned");
      break;
    case FRAMESETSTATUS_DONE:
      _distren_asprintf(&status, "%s", "completed");
      break;
    case FRAMESETSTATUS_CANCELED:
      _distren_asprintf(&status, "%s", "canceled");
  }

  printf("frame #: %d --> %s", frame->num, status);
}

void printJob(struct distrenjob *job)
{
  int counter;
  printf("frame_num: status");
  for(counter = 0; counter < job->total_frames; counter++)
    {
      printFrameInfo(&job->frameset[counter]);
    }
}

void printJobInfo(struct distrenjob *job)
{
  printf("type: %d", job->type);
  printf("name: %s", job->email);
  printf("submitter: %s", job->submitter);
  printf("e-mail: %s", job->email);
  printf("priority, %d", job->priority);
  printf("completed: %d", job->completed_frames);
  printf("assigned: %d", job->assigned_frames);
  printf("total: %d", job->total_frames);
  printf("watchdog: %d", job->watchdog_forgiveness);
  printf("hibernate: %d", job->hibernate);
  printf("prev_frame: %d", job->prev_frame_index);
}

void printAllJobnums(struct distrenjob *head)
{
  struct distrenjob *current_job;
  int total_jobs;
  printf("job numbers in the order they will be processed:");

  total_jobs = 0;
  for(current_job = head; !current_job; current_job = current_job->next)
    {
      printf("%d", current_job->jobnum);
      total_jobs++;
    }

  printf("%d jobs in queue", total_jobs);
}

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

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

  /* Argument-parser */
  int counter;
  int test; // Have some fun if-ness that does fun stuff when this is 1


  struct distrenjob head;

  int cont;
  struct distrend_listenset *listenset;
  struct distrend_config *config;

  enum clientstatus
  {
    CLIENTSTATUS_UNINITIALIZED = 0,
    CLIENTSTATUS_BUSY = 1,
    CLIENTSTATUS_IDLE = 2
  } clientstatus;

  // initialize general_info struct, this should be done by start_data()
  general_info.jobs_in_queue = 0;
  general_info.free_clients = 0;
  general_info.rendering_clients = 0;
  general_info.total_finished_jobs = 0;
  general_info.total_frames_rendered = 0;
  general_info.highest_jobnum = 0;
  general_info.hibernate = 0;

  int command;
  jobnum_t jobnum;
  struct distrenjob *tmp_job;
  struct frameset *tmp_frame;
  int type;
  char *name;
  char *submitter;
  char *email;
  int priority;
  int width;
  int height;
  int start_frame;
  int end_frame;
  size_t read_buf;

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

  xmlinit();

  test = 0;
  for(counter = 0; counter < argc; counter ++)
    {
      if(strcmp(argv[counter], "-h") == 0)
	{
	  fprintf(stderr, "Usage: distrend [option] \nStarts the distrend server\n\t-h\tshow this help\n\t-t\tlaunches queue testing interface \n");
	  return 2;
	}

      else if(strcmp(argv[counter], "-t") == 0)
	{
	  fprintf(stderr, "Entering into test mode...\n\n");
	  test=1;
	}
    }
  cont = 1;
  memset(&head, '\0', sizeof(struct distrenjob));

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

  distrend_do_config(argc, argv, &config);



  while(test == 1)
  {
    fprintf(stderr, "Welcome to DistRen Alpha Interactive Test Mode\n\n");
    fprintf(stderr, "\t1 \tPrint all frames in a job\n");
    fprintf(stderr, "\t2 \tExamine certain job\n");
    fprintf(stderr, "\t3 \tGet a frame to render\n");
    fprintf(stderr, "\t4 \tAdd a job\n");
    fprintf(stderr, "\t5 \tDelete a job\n");
    fprintf(stderr, "\t6 \tPrint jobnums in queue\n");
    fprintf(stderr, "\t7 \tQuit\n");

    scanf("%d", &command);

    switch(command)
    {
    case 1:
      fprintf(stderr, "Job number: ");
      scanf("%d", &jobnum);
      printJob(distrenjob_get(&head, jobnum));
      break;
    case 2:
      fprintf(stderr, "Job number: ");
      scanf("%d", &jobnum);
      printJobInfo(distrenjob_get(&head, jobnum));
      break;
    case 3:
      find_jobframe(&head, &tmp_job, &tmp_frame);
      fprintf(stderr, "Job#:%d\n", tmp_job->jobnum);
      fprintf(stderr, "Frame#:%d\n", tmp_frame->num);
      break;
    case 4:
      name = NULL;
      submitter = NULL;
      email = NULL;

      fprintf(stderr, "\nType: \n\t 1 \t blender\n\t 2 \t povray\n"); scanf("%d", &type);
      fprintf(stderr, "\nName: ");        scanf("\n"); getline(&name, &read_buf, stdin);
      fprintf(stderr, "\nSubmitter: ");                getline(&submitter, &read_buf, stdin);
      fprintf(stderr, "\nEmail: ");                    getline(&email, &read_buf, stdin);
      fprintf(stderr, "\nPriority: ");                 scanf("%d", &priority);
      fprintf(stderr, "\nStart frame: ");              scanf("%d", &start_frame);
      fprintf(stderr, "\nEnd frame: ");                scanf("%d", &end_frame);
      fprintf(stderr, "\nWidth: ");                    scanf("%d", &width);
      fprintf(stderr, "\nHeight: ");                   scanf("%d", &height);
      prepare_distrenjob(&head, type, name, submitter, email, priority, start_frame, end_frame, width, height);
      break;
    case 5:
      fprintf(stderr, "\nJob number: ");
      scanf("%d", &jobnum);
      distrenjob_remove(&head, distrenjob_get(&head, jobnum));
      break;
    case 6:
      printAllJobnums(&head);
      break;
    case 7:
      fprintf(stderr,"Goodbye.\n");
      return 0;
    default:
      fprintf(stderr, "Invalid input, please try again.\n");
    }
  }

  distrend_listen(&listenset, config);
  /* This is called the "main loop" */
  while(cont)
    {
      struct distren_action *action;
      int clientsays = 0; /*< 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 */
      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
	    remotio_send_to_client(frame->num, job->jobnum); // Pseudo-sends data to client
	}
      /* If the client states that they finished the frame */
      	if(clientsays == DISTREN_REQUEST_DONEFRAME){
      	  clientstatus = CLIENTSTATUS_IDLE; // Sets the client back to idle
      	  finish_frame(&head, job, frame->num); // @TODO: Make sure this actually works.
      	}

      distrend_action_free(action);
    }

  distrend_unlisten(listenset);
  distrend_config_free(config);

  xmlcleanup();

  return 0;
}