package nl.ru.ai.exercise5;

import static nl.ru.ai.exercise5.Maze.*;

import java.util.ArrayList;

//Flauwrens de Bruin 1002199 && Roel van der Heijden 4822641
//Added displayRoute() and showMap() because why not
public class Exercise5
{
  public static void main(String[] arguments)
  {
    ArrayList<Candidate> candidates=new ArrayList<Candidate>();
    solve(candidates,0);
  }

  /**
   * Uses breadth first search to find the shortest path from Miltank to Azumarill
   *
   * @param candidates
   * @param c
   */
  private static void solve(ArrayList<Candidate> candidates, int c)
  {
    assert candidates!=null:"ArrayList needs to be initialized";
    assert c>=0:"cannot be negative";
    candidates.add(new Candidate(new Attempt(1,7),0));
    boolean found=false;
    while(c<candidates.size()&!found)
    {
      int row=candidates.get(c).attempt.row;
      int col=candidates.get(c).attempt.col;
      if(hasRabbit(row,col))
      {
        showSolution(candidates,c);
        displayRoute(candidates,c);
        found=true;
      } else
      {
        checkPath(candidates,c,row-1,col);
        checkPath(candidates,c,row+1,col);
        checkPath(candidates,c,row,col-1);
        checkPath(candidates,c,row,col+1);
        c++;
      }
    }
  }

  /**
   * Checks if a path/direction is new and if it's valid
   * Adds a new/valid path to the candidates ArrayList
   *
   * @param candidates
   * @param c
   * @param row
   * @param col
   */
  private static void checkPath(ArrayList<Candidate> candidates, int c, int row, int col)
  {
    assert candidates!=null:"ArrayList needs to be initialized";
    assert c>=0:"cannot be negative";
    assert row>=0&&row<maze.length: "row out of bounds";
    assert col>=0&&col<maze[0].length: "column out of bounds";

    if(!hasWall(row,col)&&!hasVisited(row,col))
      candidates.add(new Candidate(new Attempt(row,col),c));
    visited(row,col);
  }

  /**
   * Shows the coordinates of a found route
   *
   * @param candidates
   * @param c
   */
  private static void showSolution(ArrayList<Candidate> candidates, int c)
  {
    assert candidates!=null:"ArrayList needs to be initialized";
    assert c>=0:"cannot be negative";
    int row=candidates.get(c).attempt.row;
    int col=candidates.get(c).attempt.col;
    if(c>0)
      showSolution(candidates,candidates.get(c).parentCandidate);
    System.out.println("row: "+row+"  col: "+col);

  }

  /**
   * Adds the found route in the maze array
   * runs showMap
   *
   * @param candidates
   * @param c
   */
  private static void displayRoute(ArrayList<Candidate> candidates, int c)
  {
    assert candidates!=null:"ArrayList needs to be initialized";
    assert maze!=null:"array needs to be initialized";
    while(c>0)
    {
      int row=candidates.get(c).attempt.row;
      int col=candidates.get(c).attempt.col;
      maze[row][col]='o';
      c=candidates.get(c).parentCandidate;
    }
    showMap();
  }

  /**
   * Shows the map stored in the maze array
   */
  private static void showMap()
  {
    assert maze!=null:"array needs to be initialized";
    for(int i=0;i<maze.length;i++)
    {
      System.out.println();
      for(int j=0;j<maze[0].length;j++)
      {
        if(i==1&&j==1)
          System.out.print("R ");
        else if(i==1&&j==7)
          System.out.print("C ");
        else if(maze[i][j]=='x')
          System.out.print("[]");
        else if(maze[i][j]=='o')
          System.out.print("o ");
        else
          System.out.print("  ");
      }
    }
  }

}