#shell.c#

#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>

#include <termios.h>
#include <sys/types.h>
#include <sys/wait.h>

#define FALSE 0
#define TRUE 1
#define INPUT_STRING_SIZE 80

#include "io.h"
#include "parse.h"
#include "process.h"
#include "shell.h"
#include "paths.h"


char cwd[1024] ;

int cmd_quit(tok_t arg[]) {
  printf("Bye\n");
  exit(0);
  return 1;
}

int cmd_help(tok_t arg[]);


int cmd_cd(tok_t arg[])
{
 
  if  (chdir(arg[0]) ==0)
   {
      getcwd(cwd,sizeof(cwd));

    }
else
{
   fprintf(stdout, "%s Error\n") ;
}
  
   return 1 ;
     
}


/* Command Lookup table */
typedef int cmd_fun_t (tok_t args[]); /* cmd functions take token array and return int */
typedef struct fun_desc {
  cmd_fun_t *fun;
  char *cmd;
  char *doc;
} fun_desc_t;

fun_desc_t cmd_table[] = {
  {cmd_help, "?", "show this help menu"},
  {cmd_quit, "quit", "quit the command shell"},
  {cmd_cd, "cd" , "change working directory"},
};

int cmd_help(tok_t arg[]) {
  int i;
  for (i=0; i < (sizeof(cmd_table)/sizeof(fun_desc_t)); i++) {
    printf("%s - %s\n",cmd_table[i].cmd, cmd_table[i].doc);
  }
  return 1;
}


int lookup(char cmd[]) {
  int i;
  for (i=0; i < (sizeof(cmd_table)/sizeof(fun_desc_t)); i++) {
    if (cmd && (strcmp(cmd_table[i].cmd, cmd) == 0)) return i;
  }
  return -1;
}

void init_shell()
{
  /* Check if we are running interactively */
  shell_terminal = STDIN_FILENO;

  /** Note that we cannot take control of the terminal if the shell
      is not interactive */
  shell_is_interactive = isatty(shell_terminal);

  if(shell_is_interactive){

    /* force into foreground */
    while(tcgetpgrp (shell_terminal) != (shell_pgid = getpgrp()))
      kill( - shell_pgid, SIGTTIN);

    shell_pgid = getpid();
    /* Put shell in its own process group */
    if(setpgid(shell_pgid, shell_pgid) < 0){
      perror("Couldn't put the shell in its own process group");
      exit(1);
    }

    /* Take control of the terminal */
    tcsetpgrp(shell_terminal, shell_pgid);
    tcgetattr(shell_terminal, &shell_tmodes);
  }
  /** YOUR CODE HERE */

   
}

/**
 * Add a process to our process list
 */
void add_process(process* p)
{
  /** YOUR CODE HERE */
    
  

}

/**
 * Creates a process given the inputString from stdin
 */
process* create_process(char* inputString)
{
 
}



int shell (int argc, char *argv[]) {
  char *s = malloc(INPUT_STRING_SIZE+1);			/* user input string */
  tok_t *t;
  tok_t *b ;			/* tokens parsed from input */
  int lineNum = 0;
  int fundex = -1;
  pid_t pid = getpid();		/* get current processes PID */
  pid_t ppid = getppid();	/* get parents PID */
  pid_t cpid, tcpid, cpgid;

  init_shell();

  printf("%s running as PID %d under %d\n",argv[0],pid,ppid);
 
//char* cwd ;
long size ;



size = pathconf(".",_PC_PATH_MAX) ;
  getcwd(cwd,sizeof(cwd)) ;

  lineNum=0;
  fprintf(stdout, "%d: ", lineNum );
 fprintf(stdout, "%s ", cwd) ;
  while ((s = freadln(stdin))){
   
    t = getToks(s); /* break the line into tokens */
   b = getToksB(s) ;
    fundex = lookup(t[0]); /* Is first token a shell literal */
    if(fundex >= 0) cmd_table[fundex].fun(&t[1]);
    else {
     cpid  = fork() ;

      int i=0 ;
      int countWord = 0 ;
      
       while(t[i] != NULL)
       {
        
         countWord++ ;
         i++ ;
       
       }

     
      
         char* test[countWord] ;

      int j =0 ;
      for(j; j<= countWord ;j++)
       {
         
       //  countWord++ ;
        test[j] = t[j] ;
       }


  
        if(pid==0)// parent
          {
          
           wait(NULL) ;
           fprintf(stdout,"parent\n") ;
           }
        else if(pid>0)
            {
                 if(countWord==2)
                     {
                       execv(t[0], test);  }
                  else if(countWord ==1)
                  execlp(test[0],test) ;
                  else 
                    {
                       if(t[1] == '>')
                         {
                             
                            
                           }
                      
                       }
                  
    
            }
          

             //execv(t[0], test);
              ///* /* fprintf(stdout,"child\n") */  */;}
        else if(pid<0)
            {fprintf(stdout,"problems\n") ;}

             

         

     //     fprintf(stdout,t[1],"/n") ;

    //  fprintf(stdout, "This shell only supports built-ins. Replace this to run programs as commands.\n");
    }
     lineNum = lineNum + 1 ;
    fprintf(stdout, "%d: ", lineNum);

fprintf(stdout, "%s ", cwd) ;

  }
  return 0;
free (cwd) ;
}