import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class MazeModel {

    /*
     *  This is the Model component.
     */

    private static int SIZE = 47;
    private MazeCell[][] myGrid;
    private MazeView myView;
    private ListStack solution;
    private int cRow, cCol, nRow, nCol;     // current,new row,col
    private Point temp;
    private boolean keepGoing;
    
    public MazeModel(MazeView view)
    {
        myGrid = new MazeCell[SIZE][SIZE];
        int setNum = 0;
        for (int r=0; r<SIZE; r++)
        {
            for (int c=0; c<SIZE; c++) 
            {
                myGrid[r][c] = new MazeCell( setNum );
                setNum++;
            }
        }
        int numSets = setNum;
        
        while ( numSets > 1 ) 
        {
            int aCol = (int)(Math.random() * SIZE);            // choose random cell
            int aRow = (int)(Math.random() * SIZE);
            int bCol = aCol;
            int bRow = aRow;
            int testdir = 0;
            while (aCol == bCol && aRow == bRow)              // and random neighbor
            {
                testdir = (int)(Math.random() * 4);
                switch (testdir) 
                {
                    case 0:
                      if (aCol > 0) bCol = aCol-1;  break;     // left cell candidate
                    case 1: 
                      if (aCol < SIZE-1) bCol = aCol+1; break; // right cell candidate
                    case 2:
                      if (aRow > 0) bRow = aRow-1; break;      // top cell candidate
                    case 3: 
                      if (aRow < SIZE-1) bRow = aRow+1; break; // bottom cell candidate
                }
            }
            
            // we have two adjacent cells both in the maze grid
            if (myGrid[aRow][aCol].getSetNumber() != myGrid[bRow][bCol].getSetNumber() ) 
            {
                // join them by going through all cells and sharing set number
                int changeToSet = myGrid[aRow][aCol].getSetNumber();
                int changeFromSet = myGrid[bRow][bCol].getSetNumber();
                for (int col=0; col<SIZE; col++) 
                {
                    for (int row=0; row<SIZE; row++) 
                    {
                        if ( myGrid[col][row].getSetNumber() == changeFromSet )
                            myGrid[col][row].setSetNumber(changeToSet);
                    }
                }
              
                // now remove common hedge
                switch (testdir) 
                {
                    case 0: myGrid[aRow][aCol].setLeftHedge(false);
                            myGrid[bRow][bCol].setRightHedge(false);
                            break;
                    case 1: myGrid[aRow][aCol].setRightHedge(false);
                            myGrid[bRow][bCol].setLeftHedge(false);
                            break;  
                    case 2: myGrid[aRow][aCol].setTopHedge(false);
                            myGrid[bRow][bCol].setBottomHedge(false);
                            break;  
                    case 3: myGrid[aRow][aCol].setBottomHedge(false);
                            myGrid[bRow][bCol].setTopHedge(false);
                            break;  
                }  // end of switch
                numSets--;
            }
        }
    
        // make an entry and exit point to the maze
        myGrid[0][0].setLeftHedge(false);
        myGrid[SIZE-1][SIZE-1].setRightHedge(false);
        
        myView = view;
        myView.updateView(myGrid);            
    }
                  
    public void stepMaze()
    {
        /* student code here */ ;
    }    
}