#include "bot.h"
#include "maze.h"

Bot::Bot( Maze& m )
    : maze( m )
{}

bool Bot::solve()
{
    maze.reset();
    maze.start();

    return findSolution( EAST ) || findSolution( SOUTH );
}

bool Bot::findSolution( Dir dir )
{
    if( maze.isGoal() ) {
        maze.getCell().setMark( true );
        return true;
    } else if( maze.move( dir ) ) {
        for( Dir ndir = nextCW( opposite( dir ) ); ndir != opposite( dir ); 
                ndir = nextCW( ndir ) ) {
            if( findSolution( ndir ) ) {
                // Solution was found in that direction.  Mark this
                // square and return home.
                maze.move( opposite( dir ) );
                maze.getCell().setMark( true );
                return true;
            }
        }

        // Nothing beyond here
        maze.move( opposite( dir ) );
    }

    // No solution involving this square.  Back up.
    return false;
}