package sudok;

import javax.swing.*;

public class Solver {

    private int[][] m = new int [9][9];
    //private JTextField[][]jt = SudokuSwing.getJt();

    public int getValue(int x,int y) {
        return m[x][y];
    }

    public void setValue(int x,int y,int z) {
    	//if(x<0||x>8||z<1||z>9||y<0||y>8){
    		//throw new IllegalArgumentException("Aja Baja");

    	//}else
        m[x][y]=z;
    }

    public void loadJt() {
        for (int i=0;i<9;i++) {
            for (int j=0;j<9;j++) {
                try {
                    setValue(i,j,SudokuSwing.getJt(i,j));
                }
                catch(Exception e){
                    //setValue(i,j,0);
                }
            }
        }
    }

    public void clear(){
    	  for (int r=0;r<9;r++) {
              for (int c=0;c<9;c++) {
                  m[r][c] = 0;
              }
          }
    }

    /** Logic check, adds the specified number val only if it fulfills all the requirements */
    public boolean tryAddNbr(int row, int col, int val) {
    	if(row<0||row>8||val<1||val>9||col<0||col>8){
    		return false;
    	}else{
    		return !(isInCol(col, val))&&!(isInRow(row, val))&&!(isInMatrix(row, col, val))&&!(hasNum(row,col))&&!(numOutOfBounds(val));
    	}
    }

    public boolean isInCol(int col, int val){
    	for( int i = 0; i<9; i++){
    		if(getValue(i, col) == val){
    			return true;
    		}
    	}
    	return false;
    }
    public boolean isInRow(int row, int val){
    	for(int i = 0; i<9; i++){
    		if(getValue(row, i) == val){
    			return true;
    		}

    	}
    	return false;
    }

    public boolean hasNum(int row, int col){
    	if(getValue(row, col)!=0){
    		return true;
    	}
    	return false;
    }
    public boolean numOutOfBounds(int val){
    	if( val > 9 || val < 1){
    		return true;
    	}
    	return false;
    }
    public boolean isInMatrix(int row, int col, int val){
    	int r = (row/3)*3;
    	int c = (col/3)*3;
    	for(int i =0; i<3; i++){
    		for(int j = 0; j<3; j++){
    			if(getValue(r+i, c+j) == val){
    				return true;
    			}
    		}
    	}
    	return false;
    }

    /** Wrapper method for solve */
   public boolean solve() {
        return solve(0, 0);
    }
   private boolean solve(int row, int col){
	   if(col == 9){
		   col=0;
		   row++;
	   }

	   if(row==9){
		   return true;
	   }
		   for(int num = 1; num<10; num++){
			   if(tryAddNbr(row,col,num)){
				   setValue(row, col, num);
				   if(solve(row, col+1)){

					   return true;
				   }
			   }else{
				   setValue(row, col, 0);
			   }
		   }
	   return false;
   }

}