#define _XOPEN_SOURCE 700
#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <limits.h>

#include <option.h>

/*
* Takes a string of the form 64, 8m, 128k, 4g, etc. and converts to bytes.
*/
int64_t string_to_bytes(char *size_str)
{
       int64_t size = 0;
       char range;
       int rc;

       rc = sscanf(size_str, " %lld %c ", (long long*) & size, &range);
       if (rc == 2) {
               switch ((int)range) {
               case 'k':
               case 'K':
                       size <<= 10;
                       break;
               case 'm':
               case 'M':
                       size <<= 20;
                       break;
               case 'g':
               case 'G':
                       size <<= 30;
                       break;
               case 't':
               case 'T':
                       size <<= 40;
                       break;
               case 'p':
               case 'P':
                       size <<= 50;
                       break;
               }
       } else if (rc == 0) {
               size = -1;
       }
       return (size);
}

/*
 * Initial revision by JK
 */

static int print_value(option_help * o){
  int pos = 0;
  if (o->arg == OPTION_OPTIONAL_ARGUMENT || o->arg == OPTION_REQUIRED_ARGUMENT){
    assert(o->variable != NULL);

    switch(o->type){
      case('p'):{
        pos += printf("=STRING");
        break;
      }
      case('F'):{
        pos += printf("=%.14f ", *(double*) o->variable);
        break;
      }
      case('f'):{
        pos += printf("=%.6f ", (double) *(float*) o->variable);
        break;
      }
      case('d'):{
        pos += printf("=%d ", *(int*) o->variable);
        break;
      }
      case('H'):
      case('s'):{
        if ( *(char**) o->variable != NULL &&  ((char**) o->variable)[0][0] != 0 ){
          pos += printf("=%s", *(char**) o->variable);
        }else{
          pos += printf("=STRING");
        }
        break;
      }
      case('c'):{
        pos += printf("=%c", *(char*) o->variable);
        break;
      }
      case('l'):{
        pos += printf("=%lld", *(long long*) o->variable);
        break;
      }
    }
  }
  if (o->arg == OPTION_FLAG && (*(int*)o->variable) != 0){
    pos += printf(" (%d)", (*(int*)o->variable));
  }

  return pos;
}

static void print_help_section(option_help * args, option_value_type type, char * name){
  int first;
  first = 1;
  option_help * o;
  for(o = args; o->shortVar != 0 || o->longVar != 0 || o->help != NULL ; o++){

    if (o->arg == type){
      if( o->shortVar == 0 && o->longVar == 0 && o->help != NULL){
        printf("%s\n", o->help);
        continue;
      }
      if (first){
        printf("\n%s\n", name);
        first = 0;
      }
      printf("  ");
      int pos = 0;
      if(o->shortVar != 0 && o->longVar != 0){
        pos += printf("-%c, --%s", o->shortVar, o->longVar);
      }else if(o->shortVar != 0){
        pos += printf("-%c", o->shortVar);
      }else if(o->longVar != 0){
        pos += printf("--%s", o->longVar);
      }

      pos += print_value(o);
      if(o->help != NULL){
        for(int i = 0 ; i < (30 - pos); i++){
          printf(" ");
        }
        printf("%s", o->help);
      }
      printf("\n");
    }
  }
}

void option_print_help(option_help * args, int is_plugin){
  option_help * o;
  int optionalArgs = 0;
  for(o = args; o->shortVar != 0 || o->longVar != 0 ; o++){
    if(o->arg != OPTION_REQUIRED_ARGUMENT){
      optionalArgs = 1;
    }

    switch(o->arg){
      case (OPTION_OPTIONAL_ARGUMENT):
      case (OPTION_FLAG):{
        if(o->shortVar != 0){
          printf("[-%c] ", o->shortVar);
        }else if(o->longVar != 0){
          printf("[--%s] ", o->longVar);
        }
        break;
      }case (OPTION_REQUIRED_ARGUMENT):{
        if(o->shortVar != 0){
          printf("-%c ", o->shortVar);
        }else if(o->longVar != 0){
          printf("--%s ", o->longVar);
        }
        break;
      }
    }
  }
  if (optionalArgs){
    //printf(" [Optional Args]");
  }
  if (! is_plugin){
    printf(" -- <Plugin options, see below>\n");
  }

  print_help_section(args, OPTION_REQUIRED_ARGUMENT, "Required arguments");
  print_help_section(args, OPTION_FLAG, "Flags");
  print_help_section(args, OPTION_OPTIONAL_ARGUMENT, "Optional arguments");
}


static int print_option_value(option_help * o){
  int pos = 0;
  if (o->arg == OPTION_OPTIONAL_ARGUMENT || o->arg == OPTION_REQUIRED_ARGUMENT){
    assert(o->variable != NULL);

    switch(o->type){
      case('F'):{
        pos += printf("=%.14f ", *(double*) o->variable);
        break;
      }
      case('f'):{
        pos += printf("=%.6f ", (double) *(float*) o->variable);
        break;
      }
      case('d'):{
        pos += printf("=%d ", *(int*) o->variable);
        break;
      }
      case('H'):{
        pos += printf("=HIDDEN");
        break;
      }
      case('s'):{
        if ( *(char**) o->variable != NULL &&  ((char**) o->variable)[0][0] != 0 ){
          pos += printf("=%s", *(char**) o->variable);
        }else{
          pos += printf("=");
        }
        break;
      }
      case('c'):{
        pos += printf("=%c", *(char*) o->variable);
        break;
      }
      case('l'):{
        pos += printf("=%lld", *(long long*) o->variable);
        break;
      }
    }
  }else{
    //printf(" ");
  }

  return pos;
}


static void print_current_option_section(option_help * args, option_value_type type){
  option_help * o;
  for(o = args; o->shortVar != 0 || o->longVar != 0 ; o++){
    if (o->arg == type){
      int pos = 0;
      if (o->arg == OPTION_FLAG && (*(int*)o->variable) == 0){
        continue;
      }
      printf("\t");

      if(o->shortVar != 0 && o->longVar != 0){
        pos += printf("%s", o->longVar);
      }else if(o->shortVar != 0){
        pos += printf("%c", o->shortVar);
      }else if(o->longVar != 0){
        pos += printf("%s", o->longVar);
      }

      pos += print_option_value(o);
      printf("\n");
    }
  }
}


void option_print_current(option_help * args){
  print_current_option_section(args, OPTION_REQUIRED_ARGUMENT);
  print_current_option_section(args, OPTION_OPTIONAL_ARGUMENT);
  print_current_option_section(args, OPTION_FLAG);
}

int option_parse(int argc, char ** argv, option_help * args, int * printhelp){
  int error = 0;
  int requiredArgsSeen = 0;
  int requiredArgsNeeded = 0;
  int i;

  for(option_help * o = args; o->shortVar != 0 || o->longVar != 0 ; o++ ){
    if(o->arg == OPTION_REQUIRED_ARGUMENT){
      requiredArgsNeeded++;
    }
  }
  for(i=1; i < argc; i++){
    char * txt = argv[i];
    int foundOption = 0;
    char * arg = strstr(txt, "=");
    int replaced_equal = 0;
    if(arg != NULL){
      arg[0] = 0;
      arg++;
      replaced_equal = 1;
    }
    if(strcmp(txt, "--") == 0){
      // we found plugin options
      break;
    }

    // try to find matching option help
    for(option_help * o = args; o->shortVar != 0 || o->longVar != 0 || o->help != NULL ; o++ ){
      if( o->shortVar == 0 && o->longVar == 0 ){
        // section
        continue;
      }

      if ( (txt[0] == '-' && o->shortVar == txt[1]) || (strlen(txt) > 2 && txt[0] == '-' && txt[1] == '-' && o->longVar != NULL && strcmp(txt + 2, o->longVar) == 0)){
        foundOption = 1;

        // now process the option.
        switch(o->arg){
          case (OPTION_FLAG):{
            assert(o->type == 'd');
            (*(int*) o->variable)++;
            break;
          }
          case (OPTION_OPTIONAL_ARGUMENT):
          case (OPTION_REQUIRED_ARGUMENT):{
            // check if next is an argument
            if(arg == NULL){
              if(o->shortVar == txt[1] && txt[2] != 0){
                arg = & txt[2];
              }else{
                // simply take the next value as argument
                i++;
                arg = argv[i];
              }
            }

            if(arg == NULL){
              const char str[] = {o->shortVar, 0};
              printf("Error, argument missing for option %s\n", (o->longVar != NULL) ? o->longVar : str);
              exit(1);
            }

            switch(o->type){
              case('p'):{
                // call the function in the variable
                void(*fp)() = o->variable;
                fp(arg);
                break;
              }
              case('F'):{
                *(double*) o->variable = atof(arg);
                break;
              }
              case('f'):{
                *(float*) o->variable = atof(arg);
                break;
              }
              case('d'):{
                int64_t val = string_to_bytes(arg);
                if (val > INT_MAX || val < INT_MIN){
                  printf("WARNING: parsing the number %s to integer, this produced an overflow!\n", arg);
                }
                *(int*) o->variable = val;
                break;
              }
              case('H'):
              case('s'):{
                (*(char **) o->variable) = strdup(arg);
                break;
              }
              case('c'):{
                (*(char *)o->variable) = arg[0];
                if(strlen(arg) > 1){
                  printf("Error, ignoring remainder of string for option %c (%s).\n", o->shortVar, o->longVar);
                }
                break;
              }
              case('l'):{
                *(long long*) o->variable = string_to_bytes(arg);
                break;
              }
              default:
                printf("ERROR: Unknown option type %c\n", o->type);
            }
          }
        }
        if(replaced_equal){
          arg[-1] = '=';
        }

        if(o->arg == OPTION_REQUIRED_ARGUMENT){
          requiredArgsSeen++;
        }

        break;
      }
    }
    if (! foundOption){
        if(strcmp(txt, "-h") == 0 || strcmp(txt, "--help") == 0){
          *printhelp=1;
        }else{
          printf("Error invalid argument: %s\n", txt);
          error = 1;
        }
    }
  }

  if( requiredArgsSeen != requiredArgsNeeded ){
    printf("Error: Missing some required arguments\n\n");
    *printhelp = -1;
  }

  if(error != 0){
    printf("Invalid options\n");
    *printhelp = -1;
  }

  return i;
}