/*

  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/>.

*/

#include "execio.h"

#include <unistd.h>

#include <sys/types.h>

#ifndef _WIN32

#include <sys/wait.h>

#endif

#include <signal.h>

#include <malloc.h>

#include <fcntl.h>

#include <stdio.h>

#include <errno.h>

int execio_open(struct execio **rem, const char *progname, char *const argv[])

{

  /* pipe used to write to child */

  int pipe_write[2];

  /* pipe used to read from child */

  int pipe_read[2];

  pid_t child;

  /* for wait(2) if needed */

  int childstatus;

  int counter;

  int counter2;

  int maxfds;

  /* create two pipes to facilitate communication with child */

  if(pipe(pipe_write))

    return 1;

  if(pipe(pipe_read))

    {

      close(pipe_write[0]);

      close(pipe_write[1]);

      return 1;

    }

  /* parent */

  child = fork();

  if(child == -1)

    {

      close(pipe_write[0]);

      close(pipe_write[1]);

      close(pipe_read[0]);

      close(pipe_read[1]);

      return 1;

    }

  if(child)

    /* the parent proc: */

    {

      /* close sides of pipe we won't use */

      close(pipe_write[0]);

      close(pipe_read[1]);

      /* setup execio struct */

      (*rem) = malloc(sizeof(struct execio));

      if(!(*rem))

	{

	  /* we should tell the child we're dead - use wait and close our end of the pipes! */

	  close(pipe_write[1]);

	  close(pipe_read[0]);

	  /* we should probably pass of the wait() call to a thread that just does boring things like that. Especially for when the server tries to connect to other servers... */

	  /* maybe we should just kill instead of term the child */

	  kill(child, SIGTERM);

	  /* the waitpid(2) seems to indicate that only when the child is terminated will this wait return. */

	  waitpid(child, &childstatus, 0); 

	}

      (*rem)->pipe_write = pipe_write[1];

      (*rem)->pipe_read = pipe_read[0];

      (*rem)->state = 0;

      (*rem)->child = child;

      return 0;

    }

  /* child */

  else

    {

      /* close unused pipes */

      close(pipe_write[1]);

      close(pipe_read[0]);

      /*

	reset stdin, stdout, and stderr to the appropriate files. OK, not stderr :-) 

      */

      dup2(pipe_read[1], STDOUT_FILENO);

      dup2(pipe_write[0], STDIN_FILENO);

      /*

	close the fds that were dup'd

       */

      close(pipe_read[1]);

      close(pipe_write[0]);

      /* 

	 close all other file descriptors. We want to keep 0, 1, and 2 open. We don't know that the last open() or pipe() always gives the highest fd number. However, I will assume that it does. Maybe this is a bad idea:

       */

      counter = pipe_write[0];

      if(counter < pipe_write[1])

	counter = pipe_write[1];

      if(counter < pipe_read[0])

	counter = pipe_read[0];

      if(counter < pipe_read[1])

	counter = pipe_read[1];

      counter2 = 0;

      maxfds = counter;

      while(counter > 2)

	{

	  if(!close(counter))

	    counter2 ++; /* record how many descriptors we still had open :-) */

	  counter --;

	}

      /* stderr is the only stream we haven't confiscated atm - just for fun - I will confiscate it later, though, to support parsing error messages */

      fprintf(stderr, "closed %d/%d fds before execing \"%s\"\n", counter2, maxfds, progname);

      /*

	now exec: execvp uses interpreter to find the file to exec

       */

      execvp(progname, argv);

      fprintf(stderr, "uh-oh, ``%s'' didn't start for execio\n", progname);

      exit(1);

    }

}

/*

  returns 1 if child has exited, 

  returns 0 if child is still alive

 */

int _execio_checkpid(struct execio *eio)

{

  int childstatus;

#ifdef _WIN32

  waitpid(eio->child, &childstatus, 0);

#else

  waitpid(eio->child, &childstatus, WNOHANG);

#endif

  /* perror()? */

  return WIFEXITED(childstatus);

}

int execio_read(struct execio *eio, void *buf, size_t len, size_t *bytesread)

{

  ssize_t ret;

  /*

    TODO: detect NULL eio? 

    TODO: errno?

    update status of eio for execio_status/to be able to cleanup subproc??

  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 "distrenjob.h"

#include "listen.h"

#include "slavefuncs.h"

#include "mysql.h"

#include "common/asprintf.h"

#include "common/execio.h"

#include "common/options.h"

#include "common/protocol.h"

#include <confuse.h>

#include <malloc.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/stat.h>

#include <sys/types.h>

#include <time.h>

#include <unistd.h>

#include <libxml/encoding.h>

#include <libxml/parser.h>

#include <libxml/tree.h>

#include <libxml/xmlmemory.h>

#include <libxml/xmlreader.h>

#include <libxml/xmlwriter.h>

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

struct general_info

{

  struct distrenjob head;

  distrend_mysql_conn_t conn;

  struct distrend_config *config;

  struct

  {

    /** general_info.xml */

    char *geninfo;

  } files;

  int jobs_in_queue;

  unsigned int free_clients;

  unsigned int rendering_clients;

  unsigned int total_finished_jobs;

  unsigned int total_frames_rendered;

  unsigned int highest_jobnum;

  int hibernate;

  time_t timestamp;

  unsigned long total_render_power;

  unsigned long total_priority_pieces;

};

/* *********************************************

   Function Prototypes

   ********************************************* */

/* ************General Functions************* */

int distrend_do();

void frame_watchdog(struct distrenjob *distrenjob_head);

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

int distrend_config_free(struct distrend_config *config);

/* **************XML Functions**************** */

void update_general_info(struct general_info *geninfo);

int import_general_info(struct general_info *general_info);

int update_xml_joblist(struct general_info *geninfo);

/* **************Test Functions**************** */

int interactiveTest(int test, struct general_info *general_info);

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

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

{

  /* Parse arguments */

  int counter;

  int test = 0; /*< Interactive mode if 1 */

  struct general_info general_info;

  struct distrend_clientset *clients;

  enum clientstatus

  {

    CLIENTSTATUS_UNINITIALIZED = 0,

    CLIENTSTATUS_BUSY = 1,

    CLIENTSTATUS_IDLE = 2

  } clientstatus;

  // xmlinit();

  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;

      }

    }

  if(distrend_do_config(argc, argv, &general_info.config))

    return 1;

  /** preset paths */

  _distren_asprintf(&general_info.files.geninfo, "%s/general_info.xml",

		    general_info.config->datadir);

  /** MySQL Connection */

  fprintf(stderr,"Connecting to mysql...\n");

  if(mysqlConnect(&general_info.conn))

    {

      fprintf(stderr, "%s:%d: mysqlConnect() failed\n", __FILE__, __LINE__);

      fprintf(stderr, "don't test mysql stuff\n");

      interactiveTest(test, &general_info);

      return 1;

    }

  fprintf(stderr,"Finished connecting!\n");

  /** Execute test function */

  interactiveTest(test, &general_info);

  distrend_listen(general_info.config, &clients);

  int slaveKey = 0; // Remotio should set me on a per-slave basis

  /* Main Loop */

  while(!general_info.config->die)

    {

      int clientsays = 0; /*< temporary example variable, will be replaced when we can handle messages */

      distrend_accept(general_info.config, clients);

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

      frame_watchdog(&general_info.head);

      struct distrenjob *job;

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

      if(clientstatus == CLIENTSTATUS_IDLE)

	{

	  if(returnnum)

	    {

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

	      sleep(10);

	    }

	  else

	}

      /* If the client states that they finished the frame */

    }

  distrend_unlisten(general_info.config->listens, clients);

  distrend_config_free(general_info.config);

  xmlcleanup();

  /** free() paths */

  free(general_info.files.geninfo);

  mysqlDisconnect(general_info.conn);

  return 0;

}

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

/**

   Performs command stored in a client's request. @TODO: Fill stub

*/

int distrend_do()

{

  return 0;

}

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

void frame_watchdog(struct distrenjob *distrenjob_head)

{

  // Replace with mysqlness, maybe

  // iterate through jobs

    // if the job has been started, checks by seeing if either to first or second frame has been started

    // FRAMESETSTATUS_UNASSIGNED

      // iterate through all frames for this job:

          //watchdog_forgiveness = seconds of forgiveness before frame is re-assigned:

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

             //   Then change the frame status to unassigned

}

/* Grabs config info from confs */

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

{

  unsigned int counter;

  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_STR_LIST("render_types", NULL, CFGF_NONE),

      CFG_END()

    };

  cfg_t *cfg_listen;

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

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

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

  if(options_init(argc, argv, &(*config)->mycfg, myopts, "daemon", &(*config)->options))

    return 1;

  /**

     grab listen blocks:

   */

  (*config)->listens = malloc(sizeof(struct distrend_listen) * (cfg_size((*config)->mycfg, "listen") + 1));

  for(counter = 0; counter < cfg_size((*config)->mycfg, "listen"); counter ++)

    {

      cfg_listen = cfg_getnsec((*config)->mycfg, "listen", counter);

      (*config)->listens[counter].port = cfg_getint(cfg_listen, "port");

      (*config)->listens[counter].sock = -1;

    }

  memset(&(*config)->listens[counter], '\0', sizeof(struct distrend_listen));

  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

*/

int sendSignal(struct remoteio *rem, char signal)

{

  size_t written;

  size_t towrite;

  char *ssignal;

  _distren_asprintf(&ssignal, "%c", signal);

  towrite = strlen(ssignal);

  while( towrite

	 && !remoteio_write(rem, ssignal, towrite, &written))

    {

      fprintf(stderr, "Sending request...\n");

      towrite -= written;

    }

  if(written)

    return 0;

  /**

     if remoteio_write returned 1, the connection

     is probably dead or there was a real error

   */

  return 1;

}

/**

   Sends the server an extended signal (request + data)

*/

int sendExtSignal(struct remoteio *rem, char signal, char *data){

  size_t written;

  size_t towrite;

  char *ssignal;

  _distren_asprintf(&ssignal, "%c%s", signal, data); // Just append the data FIXME: We should do this differently

  towrite = strlen(ssignal);

  while( towrite

          && !remoteio_write(rem, ssignal, towrite, &written))

     {

       fprintf(stderr, "Sending request...\n");

       towrite -= written;

     }

   if(written)

     return 0;

   /**

      if remoteio_write returned 1, the connection

      is probably dead or there was a real error

    */

   return 1;

}

/**

   Grabs the xml DOM node reached by an XPath.

   @param path an XPath that lead to DOM node

   @return the first node associated with the path or NULL if there is no match

 */

xmlNodePtr xml_quickxpath(xmlXPathContextPtr xpathctxt, xmlChar *path)

{

  xmlNodePtr toreturn;

  xmlXPathObjectPtr xmlxpathobjptr;

  xmlxpathobjptr = xmlXPathEval(path, xpathctxt);

  if(!xmlxpathobjptr

     || !xmlxpathobjptr->nodesetval->nodeNr)

    {

      fprintf(stderr, "XPath resolution failed for ``%s'' in ``%s'' (``%s'')\n", path, xpathctxt->doc->name, xpathctxt->doc->URL);

      return (xmlNodePtr)NULL;

    }

  toreturn = *(xmlxpathobjptr->nodesetval->nodeTab);

  xmlXPathFreeObject(xmlxpathobjptr);

  return toreturn;

}

/** Stub for deleting job data from the disk. @TODO: unstubify me! */

int delete_jobdata(int jobnum, char *datadir)

{

  char *jobpath;

  _distren_asprintf(&jobpath, "%s/%d", datadir, jobnum);

  // rmdir(jobpath);

  fprintf(stderr, "Please manually remove %s. Automatic removal is currently not implemented.\n", jobpath);

  return 0;

}

/** Function referenced by curlget() to write data to disk. */

size_t curl_writetodisk(void *ptr, size_t size, size_t nmemb, FILE *stream)

 {

    return fwrite(ptr, size, nmemb, stream);

  }

/** Helper function for cURL's progress display */

{

fprintf(stderr,"Downloading: %f%% complete\r",d/t*100);

return 0;

}

/** Retrieves a URL with cURL and saves it to disk */

  fprintf(stderr,"Preparing to download %s\n",url);

  double *Bar; // Stores cURL progress display info

  CURL *curl;

  CURLcode res;

  FILE *outfile;

  curl = curl_easy_init();

    outfile = fopen(out, "w"); // Open where we're writing to

    if(outfile == NULL)

      return 2; // Output dir doesn't exist

    curl_easy_setopt(curl, CURLOPT_URL, url);

    curl_easy_setopt(curl, CURLOPT_WRITEDATA, outfile);

    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, curl_writetodisk); // this MUST be set for win32 compat.

    curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0);

    curl_easy_setopt(curl, CURLOPT_PROGRESSDATA, &Bar);

    res = curl_easy_perform(curl);

    curl_easy_cleanup(curl);

  }

  fprintf(stderr,"\n"); // Clears out he progressbar's carriage return

  return res; // 0 is OK, 1 is 404 or other error

}

/** Posts a file to a url with cUrl */

  char *targetname = "uploadedfile"; // Name of the target in the php file on the server (Don't change me unless you have different PHP code)

  CURL *curl;

  CURLcode res;

  struct curl_httppost *formpost=NULL;

  struct curl_httppost *lastptr=NULL;

  struct curl_slist *headerlist=NULL;

  static const char buf[] = "Expect:";

  char *sjobnum;

  char *sframenum;

  char *sslavekey;

  _distren_asprintf(&sjobnum,"%d",jobnum);

  _distren_asprintf(&sframenum,"%d",framenum);

  _distren_asprintf(&sslavekey,"%d",slavekey);

  curl_global_init(CURL_GLOBAL_ALL);

  /* jobnum field... */

   curl_formadd(&formpost,

                &lastptr,

                CURLFORM_COPYNAME, "jobnum",

                CURLFORM_COPYCONTENTS, sjobnum, CURLFORM_END);

  /* framenum field... */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "framenum",

               CURLFORM_COPYCONTENTS, sframenum, CURLFORM_END);

  /* slavekey field... */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "slavekey",

               CURLFORM_COPYCONTENTS, sslavekey, CURLFORM_END);

  /* upload field... */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, targetname,

               CURLFORM_FILE, filename,

               CURLFORM_END);

  /* filename field... */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "filename",

               CURLFORM_COPYCONTENTS, filename,

               CURLFORM_END);

  /* submit field, not usually needed, just in case... */

  curl_formadd(&formpost,

               &lastptr,

               CURLFORM_COPYNAME, "submit",

               CURLFORM_COPYCONTENTS, "send",

               CURLFORM_END);

  curl = curl_easy_init();

  headerlist = curl_slist_append(headerlist, buf);

    /* Setting the URL to get the post, and the contents of the post */

    curl_easy_setopt(curl, CURLOPT_URL, url);

    curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);

    res = curl_easy_perform(curl);

    curl_easy_cleanup(curl);

    /* cleanup the formpost junk */

    curl_formfree(formpost);

    curl_slist_free_all (headerlist);

    free(sjobnum);

    free(sframenum);

    free(sslavekey);

  return res;

}

/** Logs the user into the server after ensuring that keys exist */

int login_user(char *username)

{

  // @TODO: Put some telnet-style auth code here unless this is obselete

  return 1; // success

}

/** Replaces wordtoreplace with replacewith in conffile (relative to SYSCONFDIR) */

int conf_replace(char *conffile, char *wordtoreplace, char *replacewith){

  int maxlinelen = 120;

  char *fileOrig;

  char *fileRepl;

  _distren_asprintf(&fileOrig, "%s/%s", SYSCONFDIR, conffile);

  _distren_asprintf(&fileRepl, "%s%s.edited", SYSCONFDIR, conffile);

  char buffer[maxlinelen+2];

  char *buff_ptr, *find_ptr;

  FILE *fp1, *fp2;

  size_t find_len = strlen(wordtoreplace);

  fp1 = fopen(fileOrig,"r");

  fp2 = fopen(fileRepl,"w");

  if (fp1 ==NULL){

    fprintf(stderr, "%s doesn't exist\n",fileOrig);

    return 0;

  }

  else if(fp2 ==NULL){

    fprintf(stderr, "Can't write a file to disk! Check permissions.\n");

    return 0;

  }

  else{

    while(fgets(buffer,maxlinelen+2,fp1))

      {

        buff_ptr = buffer;

        while ((find_ptr = strstr(buff_ptr,wordtoreplace)))

        {

           while(buff_ptr < find_ptr)

             fputc((int)*buff_ptr++,fp2);

           fputs(replacewith,fp2);

           buff_ptr += find_len;

         }

         fputs(buff_ptr,fp2);

      }

    rename(fileRepl, fileOrig);

  }

  fclose(fp2);

  fclose(fp1);

  fprintf(stderr,"Wrote conf file...\n");

return 1; // Success

}

/* Executors */

/** Executor function for Blender operations */

int exec_blender(char *input, char *output, int frame)

{

  int ret;

  char *frame_str;

  _distren_asprintf(&frame_str, "%i", frame);

  char *command = "blender"; // @TODO: We currently expect this to be in PATH

  char *cmd[] = { command, "-b", input, "-o", output, "-f", frame_str, "-t", "0", (char *)NULL }; // arguments for blender

  fprintf(stderr,"Preparing to execute command: %s -b %s -o %s -f %s\n", command, input, output, frame_str);

  char buf[20];

  struct execio *testrem;

  size_t readlen;

  fprintf(stderr,"Executing: %s\n", frame_str);

  ret = execio_open(&testrem, command, cmd);

  if(ret)

    {

      fprintf(stderr, "error running blender\n");

      return 1;

    }

  buf[19] = '\0';

  while(!execio_read(testrem, buf, 19, &readlen))

    {

       buf[readlen] = '\0';

       fprintf(stderr, "read \"%s\"\n", buf);

    }

  execio_close(testrem);

  free(frame_str);

  return ret;

}

void xmlinit()

{

  xmlInitParser();

  xmlXPathInit();

}

{

  int command;

  int test = 1;

  int jobnum = 0;

  int framenum = 0;

  int slavekey = 0;

  fprintf(stderr,"Hello!\n");

  char tmpString1[100] = "";

  char tmpString2[100] = "";

  char *uploadURL = "http://distren.org/slaveUpload.php";

  while(test == 1)

   {

     fprintf(stderr, "Welcome to DistRenSlave Alpha Interactive Test Mode\n\n");

     fprintf(stderr, "\t1 \tTest posting (uploading) data\n");

     fprintf(stderr, "\t2 \tTest getting frame from server\n");

     fprintf(stderr, "\t3 \tTest data downloading\n");

     fprintf(stderr, "\t4 \tTest archive decompression\n");

     fprintf(stderr, "\t5 \tQuit\n");

     scanf("%d", &command);

     switch(command)

     {

     case 1:

       fprintf(stderr,"Path to output file to upload: ");

       scanf("%99s", tmpString1);

       fprintf(stderr,"Framenum that is being uploaded: ");

       scanf("%d", &framenum);

       fprintf(stderr,"Jobnum that frame belongs to: ");

       scanf("%d", &jobnum);

       fprintf(stderr,"Slavekey that rendered this output: ");

       scanf("%d", &slavekey);

       uploadOutput(tmpString1, uploadURL, jobnum, framenum, slavekey);

       break;

     case 2:

       fprintf(stderr,"Remotio not implemented yet!\n");

       break;

     case 3:

       fprintf(stderr,"URL to file: ");

       scanf("%s", tmpString1);

       fprintf(stderr,"Local save path (including filename): ");

       scanf("%s", tmpString2);

       if(downloadTar(tmpString1, tmpString2))

         fprintf(stderr,"Error downloading!\n");

       else

         fprintf(stderr,"Success!\n");

       break;

     case 4:

       fprintf(stderr,"Jobnum to decompress: ");

       scanf("%d", &jobnum);

       fprintf(stderr,"Path to compressed data: ");

       scanf("%s", tmpString2);

       unpackJob(datadir, tmpString1);

       break;

     case 5:

       test = 0;

       break;

     default:

       fprintf(stderr, "Invalid input, please try again.\n");

       break;

     }

   }

}

/*

int runBenchmark(int slavekey, char *datadir){

  // Execute blender

  if(exec_blender(pathtoJobfile, pathtoOutput, framenum))

    {

      fprintf(stderr,"Error running Blender. Check your installation and/or your PATH.\n");

      _web_resetframe(slavekey, password, jobnum, framenum);  // Unassign the frame on the server so other slaves can render it

      return 1;

    }

  free(pathtoJobfile);

  struct stat buffer;

  int fstatus = stat(pathtoOutput, &buffer);

  if(fstatus == -1){

    fprintf(stderr,"*** Frame was not rendered correctly! Scene may not have camera, or your blender installation is not working.\n");

    _web_resetframe(slavekey, password, jobnum, framenum);  // Unassign the frame on the server so other slaves can render it

    return 1;

  }

}

*/

/* simpleSlave functions */

/** Memory struct for curl */

struct _web_memorystruct {

  char *memory;

  size_t size;

};