/*
  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/>.

*/

#include "mysql.h"
#include <mysql/mysql.h>

#include "common/asprintf.h"
#include "common/protocol.h"

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <fcntl.h>

/**
   local types
 */

#define SEVENTY_FIVE 75
#define FORTY_TWO 42

struct distrend_mysql_con 
{
  MYSQL *mysqlconn;
  short pointlesscheck;
};

struct distrend_mysql_result
{
  MYSQL_RES *mysqlresult;
  short pointlesscheck;
};

/** 
    funcs
 */

int mysqlConnect(struct distrend_mysql_con **conn)
{
  MYSQL *mysqlconn;

  char *server = "zserver1";
  char *user = "distren";
  char *password = "secretpassword";
  char *database = "distren";

  mysqlconn = mysql_init(NULL);
  mysql_options(mysqlconn, MYSQL_OPT_RECONNECT,"true");

  if(!mysql_real_connect(mysqlconn, server, user, password, database, 0, NULL, 0))
    {
      fprintf(stderr, "%s\n", mysql_error(mysqlconn));
      return 1;
    }

  *conn = malloc(sizeof(struct distrend_mysql_con));
  if(!*conn)
    {
      mysql_close(mysqlconn);
      mysql_server_end();
      return 2;
    }
  (*conn)->mysqlconn = mysqlconn;
  (*conn)->pointlesscheck = SEVENTY_FIVE;

  return 0;
}

int mysqlDisconnect(distrend_mysql_con_t conn)
{
  /**
     check if this handle is valid
   */
  if(conn->pointlesscheck != SEVENTY_FIVE)
    fprintf(stderr, "warning, I was passed a bad struct distrend_mysql_con...\n");

  /**
     invalidate handle :-D
   */
  conn->pointlesscheck ++;

  mysql_close(conn->mysqlconn);
  mysql_server_end();
  free(conn);

  return 0;
}


distrend_mysql_result_t mysqlQuery(distrend_mysql_con_t conn, char *query)
{
  MYSQL_RES *result;
  distrend_mysql_result_t distrenresult;

  /**
     pointless sanity check
  */
  if(conn->pointlesscheck != SEVENTY_FIVE)
    fprintf(stderr, "warning, I was passed a bad struct distrend_mysql_con...\n");
  
  /** make sure that connection is still alive
   */
  if(mysql_ping(conn->mysqlconn))
    fprintf(stderr, "MySQL Connection _was_ broken or may be broken, I'm not sure exactly what this return value means\n");

  if (mysql_query(conn->mysqlconn, query))
     fprintf(stderr, "%s\n", mysql_error(conn->mysqlconn));

  result = mysql_use_result(conn->mysqlconn);

  distrenresult = malloc(sizeof(struct distrend_mysql_result));
  if(!distrenresult)
    {
      mysql_free_result(result);
      return NULL;
    }
  
  distrenresult->mysqlresult = result;
  distrenresult->pointlesscheck = FORTY_TWO;
  
  return distrenresult;
}

int mysqlResultFree(distrend_mysql_result_t result)
{
  if(result->pointlesscheck != FORTY_TWO)
    fprintf(stderr, "%s:%d: I didn't get the type of handle I wanted\n", __FILE__, __LINE__);

  mysql_free_result(result->mysqlresult);
  free(result);

  return 0;
}

/**
   Querying Functions
 */

/** Finish-Setter: Sets a frame to the "completed" status.*/
// @QUERY: update `distren`.`Job` set `Finish_Confirmed`=1 where `Job_Key`='1' and `Frame` = somenumber;
void finish_frame(int slaveKey, int jobKey, int frameNum, distrend_mysql_con_t conn)
{
  MYSQL_RES *result;
  MYSQL_ROW row;

  char *query = "update `distren`.`Job` set `Finish_Confirmed`=1 where `Job_Key`='1' and `Frame` = somenumber;";
  result = mysqlQuery(conn, query);

  // Check to make sure the slavekey is the one who rendered the frame before finishing :D
  /*
  distrenjob->frameset[frame].status = FRAMESETSTATUS_DONE;
  distrenjob->total_render_time = distrenjob->total_render_time + (clock() - distrenjob->frameset[frame].start_time);
  distrenjob->completed_frames ++;
  distrenjob->assigned_frames --;
  geninfo->total_frames_rendered ++; //< Increase total frames var for stats
  update_general_info(geninfo);
  updateJobStatsXML(distrenjob);
  */
}

/** Changes the priority of an existing (and maybe running) job. @arg head I may end up changing the head if job == head */
// @QUERY: update `distren`.`Job` set `Priority`='12', `Finish_Confirmed`=1 where `Job_Key`='1';
int change_job_priority(int jobKey, int newPriority, distrend_mysql_con_t conn){
  /*
  struct distrenjob *current_job;
  struct distrenjob *prev_job;
  char *serialname;

  distrenjob_remove(geninfo, job);
  job->priority = new_priority;

  prev_job = &geninfo->head;

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

      //  if job was not yet started

    {
      distrenjob_enqueue(geninfo, job);
      return 0;
    }


    // iterate through linked list of jobs
    for(current_job = &geninfo->head;
        current_job != NULL
          && job->priority > current_job->priority;
        current_job = current_job->next)
      prev_job = current_job;

    prev_job->next = job;
    job->next = current_job;


  update_xml_joblist(geninfo);
  // reserialize after changes
  job_getserialfilename(&serialname, geninfo, job->jobnum, 0);
  distrenjob_serialize(job, serialname);
  free(serialname);
*/
  return 0;
}

/**
  Frame Finder: Finds a frame for a slave to render
*/
// @QUERY: Frame_Get()
int find_jobframe(int slaveKey, int *jobKey, int *frameNum, distrend_mysql_con_t conn)
{
  /*
  if(geninfo->hibernate)
    return 1;

  unsigned int frame_counter;
  unsigned short int found;

  struct distrenjob *distrenjob_ptr;

  found = 0;
  // iterate through jobs from first to last
  for(distrenjob_ptr = geninfo->head.next; distrenjob_ptr && !distrenjob_ptr->hibernate; distrenjob_ptr = distrenjob_ptr->next)
  {
    for(frame_counter = (distrenjob_ptr->prev_frame_index + 1); frame_counter < distrenjob_ptr->total_frames; frame_counter ++)
    {
      if(distrenjob_ptr->frameset[frame_counter].status == FRAMESETSTATUS_UNASSIGNED) // jobframe found
      {
        found = 1;
        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)
        break;
    }

    if(found)
      break;
  }

  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;
}