/* This is one of the cipher files for the cipher interface written
** by wart@ugcs.caltech.edu
**
** Please don't steal my code without my permission.
**
*/

#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#include "term.h"
#include "types.h"
#include "ctypes.h"

cadenus::cadenus(){
  *cipher = (char) NULL;
  ocipher = NULL;
  clen = 25;
  period = 0;
  period_set = FALSE;
}

int cadenus::execute_option(char option){
  int valid = TRUE;

  switch(option){
    case ROTATE:
      rotate();
      break;
    case MOVE:
      move_stuff();
      break;
    case ALPHFIT:
      fit_columns();
      break;
    case UNDO:
      undo();
      key.init();
      break;
    default:
      valid = base_exec_option(option);
      break;
  }

  return valid;
}

int cadenus::set_period(int newperiod){
  length = strlen(cipher);
  clen = 25;

  if(period_set == FALSE || newperiod){

    period = newperiod;

    if(!period){
      if( length%clen != 0){
	msgerror("Bad length for Cadenus cipher.  Length must be a multiple of 25.");
	period_set = FALSE;
      }
      else{
	length = strlen(cipher);
	period = length / clen;
	period_set = TRUE;
      }
    }
    else
      period_set = TRUE;
    
    setup_key();
  }

  return period_set;
}

void cadenus::init_cipher(){
  if(ocipher == NULL){
    ocipher = strdup(cipher);
    length = strlen(cipher);
    clen = 25;
  }
}

void cadenus::setup_key(){
  int i;

  key.init(period);
  for(i = 0; i < period; i++){
    key.alter('a', i);
  }
}

void cadenus::rotate(){
  int column, rot, i;
  char temp_str[STRINGLENGTH];

  /* Get the column
  */

  prompt("Rotate which column (* for all)? ");
  read_line(temp_str);
  if(*temp_str == '*')
    column = 0;
  else
    (void)sscanf(temp_str, "%d", &column);

  /* Get the amount to rotate
  */

  prompt("Rotate down by how much? ");
  read_line(temp_str);
  if(sscanf(temp_str, "%d", &rot) != 1){
    msgerror("Bad rotation value.");
  }
  else if(column == 0){
    for(i = 0; i < period; i++){
      _rotate_column(i, rot);
    }
  }
  else if(column > 0 && column <= period){
    _rotate_column(column-1, rot%25);
  }
  else{
    msgerror("Bad values.");
  }
}

void cadenus::_rotate_column(int column, int rot){
  rot += 25;
  rot %= 25;
  rotate_column(column, rot);
  rot = 25 - rot;
  key.alter((key.intval(column)+rot+25)%25+'a', column);
}

void cadenus::move_stuff(){
  char temp_str[STRINGLENGTH];
  char i;
  int column1, column2;

  prompt("Interchange which two columns/rows? (ex: 1,2) ");
  read_line(temp_str);
  if(sscanf(temp_str, "%d,%d", &column1, &column2) != 2)
    msgerror("Bad input format.");
  else if(column1 <= period && column2 <= period && column1 > 0 && column2 > 0){
    column1--, column2--;
    interchange_columns(column1, column2);
    i = key.val(column1);
    key.alter(key.val(column2), column1);
    key.alter(i, column2);
  }
  
  else{
    msgerror("Bad column number.");
  }
}

void cadenus::fit_columns(){
  char temp_str[STRINGLENGTH];
  int col1, col2, i;

  prompt("Fit which two columns (eg. 1,2 or * for all)? ");
  read_line(temp_str);
  if(*temp_str == '*'){
    for(i = 1; i < period; i++){
      _fit_columns(i-1, i);
    }
  }
  else if(sscanf(temp_str, "%d,%d", &col1, &col2) != 2){
    msgerror("Bad input.");
  }
  else if(col1 < 1 || col2 < 1 || col1 > period || col2 > period){
    msgerror("Bad values.");
  }
  else{
    col1--, col2--;
    _fit_columns(col1, col2);
  }
}

void 
cadenus::_fit_columns(int col1, int col2){
    char *colstring1, *colstring2;
    int rot;

    colstring1 = strdup(get_column_string(col1));
    colstring2 = strdup(get_column_string(col2));

    rot = find_best_fit(colstring1, colstring2);

    rotate_column(col2, rot);
    rot = (rot+25)%25;
    rot = 25-rot;
    key.alter((key.intval(col2)+rot+25)%25+'a', col2);

    free(colstring1);
    free(colstring2);
}

void cadenus::show_menu(){
  menu(1, "(R)otate column  (A)lphabet fit  (M)ove columns  (U)ndo changes  (W)rite  (Q)uit");
}

void cadenus::show_key(){
  int i;
  char c;

  for(i = 0; i < period; i++){
    c = key.val(i);
    if(isalpha(c))  c = cad_conv(c);
    else c = 'a';
    put_char(toupper(c), 2*i+3, 1);
    put_char(toupper(c), 2*i+2*period+8, 1);
  }
}

void cadenus::show_cipher(){
  int i;

  /* Print the row/column numbers
  */

  for(i = 0; i < period; i++)
    (void)put_char((i+1)%10 + '0', 2*i+3, 0);
  
  if(clen > 17)
    for(i = 0; i < period; i++)
      (void)put_char((i+1)%10 + '0', 2*i+2*period+8, 0);

  /* Print the cipher
  */

  for(i = 0; i < length; i++){
    if(i < 17*period)
      (void)put_char(cipher[i], (i%period)*2+3, (i/period) + 2);
    else
      (void)put_char(cipher[i], (i%period)*2+8+2*period, (i/period) + 2-17);
  }
}

void cadenus::decipher(char *string){
  strcpy(string, cipher);
}