/*
  Copyright 2008 Nathan Phillip Brink, Ethan Zonca

  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. */

 /* Just some notes -- Ethan Zonca
 * ++ Make data availible for other apps to parse
 * Server<==>Client Communication
 * Upload while rendering
 */


#include "execio.h"
#include "options.h"
#include <confuse.h>
#include <stdio.h>
#include <malloc.h>

#define MAX_BLENDJOBS 100 // maximum number of stored jobs in memory, per job type (lux/blend). Eventually we can dump this data to disk, or atleast the remainder not in memory...

/* internally defined funcs */
void status_report_generator();


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

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

// Stores config info? editmycomment
struct distrend_config
{
  cfg_t *mycfg;
  struct options_common *options;
  struct distrend_listen **listens; /*< Null terminated array of structs */
};



/*
 frame[frame] Status Assignments:
  "NULL" - don't render me
  "0" - canceled
  "1" - unassigned
  "2" - assigned to slave
  "3" - completed by slave and uploaded

 Have a script crawl through each job in the arrays, priority-biased, and assign a frame to each slave.
 Then we will need some sort of watchdog to monitor slaves on the main server to check for stales. Maybe not worry about this for now.
*/



// Stores Blender Job Info
struct blendjob {
  char *name;
  char *submitter;
  char *email;
  int priority;  // 1 is lowest, 10 is highest, 0 is done
  int percent_done;
  int completed_frames; // number of completed frames for stats/etc
  int assigned_frames; // number of assigned frames (that are not yet completed) for stats/etc
  int total_frames; // how many frames are in the animation for stats/etc
  struct frameset *frameset;
} blendjob[MAX_BLENDJOBS];


// Frameset Structure
struct frameset {
	int frame_num; // frame number to render
	char slave_name; // user that frame is assigned to
	int frame_status; // status of frame, 0= unassigned, 1= taken, 2= done
} frameset[]; // Frameset array is generated by status_report_generator function
                         // Using this method to save memory, because if animation starts on a high frame number, it would waste a lot of RAM on empty structures




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

// **** Finish-Setter: Sets a frame to the "completed" status.
void finish_frame(int frame){
  blendjob[jobnum].frameset[frame].frame_status = 2;
}


// **** Queuer: Adds files to the queue
void queue(int type, char *name, char *submitter, char *email, int priority, int mode, int spp, struct frameset *frameset) {
	// Type: 1 = blender, add more types later
	// jobnum is the next available job number
	if(type == 1){
    blendjob[jobnum].name = name;
    blendjob[jobnum].submitter = submitter;
    blendjob[jobnum].email = email;
    blendjob[jobnum].priority = priority;
    blendjob[jobnum].frameset = frameset;
  }
  else{
    // Throw error.
  }
jobnum++; // Advance the jobnumber for the next queued job
}


// **** Status Report Generator: figures out how much of the job is done, where jobnum corresponds to the job number
// This uses pointers, so when it is run it updates certain values in memory
void status_report_generator(){

	while(blendjob[(hcfjob+1)].priority == 0)  //If the job after the highest consecutively finished job is finished
		hcfjob++;  // adds 1 to the highest consecutively finished job and checks the next one, till the job after the hcfjob is not done

	int num1 = hcfjob+1; // to scan through jobs
	int num2 = 0;		 // to scan through frames

	while(num1 <= highest_jobnum){
			if(blendjob[num1].priority != 0){ // If the job is not done, scan it

				float finished_frames = 0; // variable that counts the completed frames
				int pending_frames = 0; // variable that counts the assigned frames
				float percent = 0;  // variable that stores the percent done of the blendjob

				while(num2 <= blendjob[jobnum].total_frames){ // If
					if(blendjob[jobnum].frameset[num2].frame_status == 2)
						finished_frames++;

					if(blendjob[jobnum].frameset[num2].frame_status == 1)
						pending_frames++;

					num2++;
				}

				percent = (finished_frames / blendjob[num1].total_frames) * 100;

				blendjob[num1].completed_frames = finished_frames;
				blendjob[num1].assigned_frames = pending_frames;
				blendjob[num1].percent_done = percent;
			}

			num1++;
		}

	}


// **** Structure Builder: This function creates frame array based on the total number of frames to be rendered, which will then be parsed by function frame_farmer.
void frame_num_struct_builder(int sframe, int eframe) {
	int jobnum_new = highest_jobnum + 1;
	int total = (sframe - eframe) +1;  // total number of frames
	int fcount = sframe; // Used to create all the frames in the structure from sframe to eframe
	int x = 0;

	blendjob[jobnum_new].total_frames = total; // sets the total number of frames in animation for status purposes

	while(x < total){
		blendjob[jobnum_new].frameset[x].frame_num = fcount;
		x++;
		fcount++;
	}

	highest_jobnum++;
}



// Frame Assigner: matches your computer up with a lovely frame to render
int frame_finder(){
	int your_frame = 0;  // your_frame is an interger value that will be given to the client as the frame number to render
	int finder_jobnum = 0;
	int frameset_count = 0; // the frameset number, note* frames in an animation don't start at zero
	short int done = 0;
	short int priority = 10;

	while(priority >= 1){ // start the scan for the next job with the highest priority, decreases priority before it loops
		finder_jobnum = hcfjob + 1; // reset it to start scanning at first uncompleted job for the pass at each priority level

		while(finder_jobnum <= highest_jobnum){  // This keeps increasing the finder_jobnum until it is higher than the highest_jobnum
			if(blendjob[finder_jobnum].priority == priority){  // looks for a job with the current priority value
				done = 1;									  // notice it starts by looking at the oldest job first
				break;
			}

			if((done) == 1)  // If it has found a job with the current priority value, it will break out of the loop
				break;    // If none is found it goes to the next job to see if it is of the current priority value
			else
				finder_jobnum++;
		} // End of increasing finder_jobnum

		if(done == 1) // if job has been found, it lets it out of the priority changer loop
			break;

		priority--; // end of decreasing priority
	}

	while(your_frame < blendjob[finder_jobnum].total_frames){ // Finds the frameset number with a frame that needs to be rendered
		if (blendjob[finder_jobnum].frameset[frameset_count].frame_status == 0)  // If frame that is not assigned has been found, frameset_count is not changed
			break;																// and frameset_count is used to give the frame number later in this funciton

		frameset_count++;  // If frame is assigned or done, it goes to next frame
	}

blendjob[jobnum].frameset[frameset_count].frame_status++; // sets the value of the frame to 2, which means its taken

your_frame = blendjob[jobnum].frameset[frameset_count].frame_num; //  Takes the frameset found in the while statement above, and extracts the frame number from it and assigns it to the int your_frame

if(your_frame == 0)  // If that job had no open frames for some reason, run the status report generator so that
	status_report_generator();  //the job priority can be changed to 0

return your_frame; // your_frame is returned as the frame to be rendered
}




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

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

// Begin non-working framework?
	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_END()
	    };

	  config = malloc(sizeof(struct distrend_config));
	  options_init(argc, argv, &config->mycfg, myopts, "server", &config->options);

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

	  return 0;
	}
// End non-working framework?



  int cont = 1;
  struct distrend_listenset *listenset;
  struct distrend_config *config;
  distrend_do_config(argc, argv, config);

  distrend_listen(&listenset, config);
  /* This is called the ``main loop'' */
  while(cont)
    {
      struct distren_action *action;

      distrend_accept(&action);
      cont = distrend_do(action);
      distrend_action_free(action);
    }

  distrend_unlisten(listenset);
  distrend_config_free(config);

  return 0;
}







/*
 * **********************************************************************************
 * Slave functions / etc resides below. Wouldn't a seperate file make this easier??
 *
 * Slave listens on server for a command in the format of each function...
 * We need if's for returns... ==> watchdog
 * **********************************************************************************
*/


// Registration on server. Needs attention. Prevent account spamming.
// Key transfer?
// Set up something like: distrend -c username email@example.com
void registeruser(char *username, char *email){
  // Logs into sandboxed user on zserver2 and registers a user. Should eventually generate a key on the server and return it to the user.
  // All created user accounts should be sandboxed accordingly, requiring a different skel, and the default shell to be rbash. Also,
  // a custom path defined in the .bash_profile of the skel is needed.
  char buf[10];
  struct execio *testrem;
  char *execargv[] =
    {
  "ssh",
  "distren_setup@protofusion.org",
  "-i",
  "setup.rsa", // default distributed key, account can only create users.
  "-p",
  "23",
  "sudo /usr/sbin/useradd",
  "-M",
  "-c",
  email,
  "-d",
  "/home/distren",
  "--gid",
  "541", // Add in shellscript to generate ssh key and return it to the user somehow
  username,
  (char *)NULL
  };
  size_t readlen;
  fprintf(stderr, "Opening stream:\n", execio_open(&testrem, "ssh", execargv));
  buf[9] = '\0'; // null-terminating the array...
  while(!execio_read(testrem, buf, 9, &readlen)) // What's with the readlen stuff?
    {
      if(readlen > 9) {
	fprintf(stderr, "!!!! Something is terribly wrong!\n");
      }
    buf[readlen] = '\0'; // Null-terminating the end of it again based on how large the data is?
    fprintf(stderr, "read \"%s\"\n", buf);
    }
  execio_close(testrem);
}


void loginuser(char *username, int secret){
  // Logs into sandboxed user on zserver2 as a client, currently does nothing
  char buf[10];
  struct execio *testrem;
  char *execargv[] =
    {
  "ssh",
  "username@protofusion.org", // username must be read from the conf
  "-i",
  "username.rsa", // Key created from registeruser()
  "-p",
  "23",
  "echo",
  "hello", // This should eventually open a non-terminating connection to the server for communication
  (char *)NULL
  };
  size_t readlen;
  fprintf(stderr, "Opening stream:\n", execio_open(&testrem, "ssh", execargv));
  buf[9] = '\0'; // null-terminating the array...
  while(!execio_read(testrem, buf, 9, &readlen)) // What's with the readlen stuff?
    {
      if(readlen > 9) {
	fprintf(stderr, "!!!! Something is terribly wrong!\n");
      }
    buf[readlen] = '\0'; // Null-terminating the end of it again based on how large the data is?
    fprintf(stderr, "read \"%s\"\n", buf);
    }
  execio_close(testrem);
}


// Executors

void exec_blender(char *input, char *output, int frame) {
  int ret;
  /* SEGFAULTAGE :-D */
  char *cmd[] = { "blender", "-b", "-o", *output, *input, "-f", *frame, (char *)0 };
  ret = execv("/usr/bin/blender", cmd);

  // OHNOBINKI! ... check this... Its supposed to send a command back to the server and run the_finisher(); function which sets the frame status to complete.
  /* You can't print the return value of a function that returns nothing (void) */
  finish_frame(frame);
}