/*
 * COMM2.C
 *
 * Matthew Dillon  28 Apr 1986
 * MORE commands
 */

#include "shell.h"

do_return()
{
   if (Src_stack) {
      fseek (Src_base[Src_stack - 1], 0, 2);
      Rval = (ac < 2) ? 1 : atoi(av[1]);
      return (-1);
   } else {
      exit ((ac < 2) ? 1 : atoi(av[1]));
   }
}


/*
 * if A < B   <, >, =, <=, >=, !=, where A and B are either:
 * nothing
 * a string
 * a value (begins w/ number)
 */

do_if(garbage, com)
char *garbage;
{
   char *v1, *v2, *v3, result, num;
   int n1, n2;

   switch (com) {
   case 0:
      if (If_stack && If_base[If_stack - 1]) {
         If_base[If_stack++] = 1;
         break;
      }
      result = num = 0;
      if (ac <= 2) {       /* if $var; */
         if (ac == 1 || strlen(av[1]) == 0 || (strlen(av[1]) == 1 && *av[1] == ' '))
            goto do_result;
         result = 1;
         goto do_result;
      }
      if (ac != 4) {
         ierror(NULL, 500);
         break;
      }
      v1 = av[1]; v2 = av[2]; v3 = av[3];
      while (*v1 == ' ')
         ++v1;
      while (*v2 == ' ')
         ++v2;
      while (*v3 == ' ')
         ++v3;
      if (*v1 >= '0' && *v1 <= '9') {
         num = 1;
         n1 = atoi(v1);
         n2 = atoi(v3);
      }
      while (*v2) {
         switch (*v2++) {
         case '>':
            result |= (num) ? (n1 >  n2) : (strcmp(v1, v3) > 0);
            break;
         case '<':
            result |= (num) ? (n1 <  n2) : (strcmp(v1, v3) < 0);
            break;
         case '=':
            result |= (num) ? (n1 == n2) : (strcmp(v1, v3) ==0);
            break;
         default:
            ierror (NULL, 503);
            break;
         }
      }
do_result:
      If_base[If_stack++] = !result;
      break;
   case 1:
      if (If_stack > 1 && If_base[If_stack - 2])
         break;
      if (If_stack)
         If_base[If_stack - 1] ^= 1;
      break;
   case 2:
      if (If_stack)
         --If_stack;
      break;
   }
   Disable = (If_stack) ? If_base[If_stack - 1] : 0;
   return (1);
}

do_label()
{
   char aseek[32];

   if (Src_stack == 0) {
      ierror (NULL, 502);
      return (-1);
   }
   sprintf (aseek, "%d %d", Src_pos[Src_stack-1], If_stack);
   set_var (LEVEL_LABEL + Src_stack - 1, av[1], aseek);
   return (1);
}

do_goto()
{
   int new;
   long pos;
   char *lab;

   if (Src_stack == 0) {
      ierror (NULL, 502);
   } else {
      lab = get_var (LEVEL_LABEL + Src_stack - 1, av[1]);
      if (lab == NULL) {
         ierror (NULL, 501);
      } else {
         pos = atoi(lab);
         fseek (Src_base[Src_stack - 1], pos, 0);
         Src_pos[Src_stack - 1] = pos;
         new = atoi(next_word(lab));
         for (; If_stack < new; ++If_stack)
            If_base[If_stack] = 0;
         If_stack = new;
      }
   }
   return (-1);      /* Don't execute reset of this line */
}


do_failat()
{
   Faillevel = 1;
   puts ("NOT IMPLIMENTED YET");
}

do_checkbrk()
{
   puts ("NOT IMPLIMENTED YET");
}

do_inc(garbage, com)
char *garbage;
{
   char *var;
   char num[32];

   if (ac == 3)
      com = atoi(av[2]);
   var = get_var (LEVEL_SET, av[1]);
   if (var) {
      sprintf (num, "%d", atoi(var)+com);
      set_var (LEVEL_SET, av[1], num);
   }
}

do_input()
{
   char in[256];

   gets(in);
   set_var (LEVEL_SET, av[1], in);
   return (1);
}

do_ver()
{
   puts (VERSION);
   return (1);
}