/*******************************************************************************
*
*  Jogo 2 - Jogo das Palavras Emaralhadas
*  Criado por: Robson Couto April, 17,2014
*  Adaptado por: Squids Arduino 
*
*                   http://squids.com.br/arduino
*
*******************************************************************************/
#include <LiquidCrystal.h>

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
char string[16];// string to be changed
char stringNormal[16];//string to be keeped
int p[]={16,16,16};//position of the spaces is the string
int i=0,n=0,m=0,c=0,dificultlevel=6,c1=0;//i,n and m are counters and c is the number of characters in the serial buffer
char aux;//variable used to keep values while changing places in the array string[]
const int buttonPin = 9; //pin of the button
int buttonState = 0,brk=0; // state of the button and variable to prevent that the string be written in the LCD many times.
int activeryeasymode=1;// 1-the fist and the last letters aren't changed,0-the first and the last letters can be changed

void setup(){
  // set up the LCD's number of columns and rows: 
  lcd.begin(16, 2);
  // initialize the serial communications:
  Serial.begin(9600);
  pinMode(buttonPin, INPUT_PULLUP);
}

void loop(){
  randomSeed(analogRead(0));
  // when characters arrive over the serial port...
  if (Serial.available()) {
    // wait a bit for the entire message to arrive
    delay(100);
    // clear the screen
    lcd.clear();
    // read all the available characters
    while (Serial.available() > 0) {
      string[i]=(Serial.read()); //store the characterers in the string
      stringNormal[i]=string[i];//copy them in the string that will be keeped
      if(string[i]==' '){
        p[c1]=i;//If there are spaces in the string, store their position
        c1++;
      }
      i++;c++;
    }
    i=0;
    while(i<dificultlevel){//The dificult level is the number of changes in the string
      n= random(0,c);// take a random index of the string to change the letter
      m=findm(n); //on the final of the code
      if((activeryeasymode==1)&&(c>3)){
        if((n!=0)&&(n!=(c-1))&&(m!=0)&&(m!=(c-1))){ // In the veryeasy mode the first and the last letter are kepped in their original position 
            if((string[n]!=' ')&&(string[m]!=' ')&&(string[n]!='\0')&&(string[m]!='\0')){  //don't changed the characters if they are spaces or the null character
            aux=string[n];//change the position of letters
            string[n]=string[m];
            string[m]=aux;  
            i++;  
            }
         }
      }else{
          if((string[n]!=' ')&&(string[m]!=' ')&&(string[n]!='\0')&&(string[m]!='\0')){  
          aux=string[n];
          string[n]=string[m];
          string[m]=aux;  
          i++;  
         }
      }             
  }
  lcd.clear();// clear the lcd
  delay(50);// a delay to sure that the lcd will not lose information
  lcd.print(string);//prinnt the changed string in the LCD
  brk=0;// let the button ready to be pressed
  }
 
  buttonState = digitalRead(buttonPin);
    if ((buttonState == LOW)&&(brk==0)) { //if the button is pressed, when brk is 0 the arduino is allowed write more than one time in the lcd
      lcd.clear();//clear the lcd
      delay(50);
      lcd.print(stringNormal);//print the original string on the lcd.
      brk=1;//  prevent the arduino from write in lcd the string more tha one time
      for(int k=0;k<16;k++){
          string[k]=' ';// clear the strings to prepare them to receive a new value 
          stringNormal[k]=' ';
      }
    } 
  i=0;n=0;m=0;c=0;c1=0;//clear all the counters
}
 
int findm(int num){// return a random number based in the first random number, is used to make the arduino change letters in the same word
  int rand=0;
  if(num<p[0]){
    rand=random(0,p[0]);
    return rand;
  }
  if((num>p[0])&&(num<p[1])){
    rand=random(p[0],p[1]);
    return rand;
  }
 
  if((num>p[1])&&(num<p[2])){
    rand=random(p[1],p[2]);
    return rand;
  }
}