/* Your code here! */
#include "maze.h"

SquareMaze::SquareMaze() {}

void SquareMaze::makeMaze(int width, int height) {
    bottomWall = new std::vector<std::vector<bool>*>(height, new std::vector<bool>(width, true));
    rightWall = new std::vector<std::vector<bool>*>(height, new std::vector<bool>(width, true));

    DisjointSets *djs = new DisjointSets();
    djs -> addelements(width * height);

    // iterating until no more walls can be deleted
    while (true) {
        std::set<int> *visited_indexes = new std::set<int>();
        // finding a wall does doesn't create a cycle
        while (true) {
            // std::cout << visited_indexes -> size() << std::endl;
            int dir = rand() % 1;
            bool down = dir == 1;

            int index;
            do {
                index = rand() % (width * height);
            } while (visited_indexes -> count(index));
            visited_indexes -> insert(index);
            int row = index / width;
            int col = index % width;
            int index_set = djs -> find(index);

            if (down) {
                // check that it is not last row
                if (row != height - 1) {
                    int down_index_set = djs -> find(index + width);
                    if (index_set != down_index_set) {
                        // delete bottom wall
                        bottomWall -> at(row) -> at(col) = false;
                        djs -> setunion(index, index + width);
                        break;
                    }
                }
            } else {
                // check that it is not last col
                if (col != width - 1) {
                    int right_index_set = djs -> find(index + 1); // check overflow case
                    if (index_set != right_index_set) {
                        rightWall -> at(row) -> at(col) = false;
                        djs -> setunion(index, index + 1);
                        break;
                    }
                }
            }

            if ((int) visited_indexes -> size() >= width * height) {
                break;
            }
        }

        if ((int) visited_indexes -> size() >= width * height) {
            break;
        }
    }
}

bool SquareMaze::canTravel(int x, int y, int dir) const {
  if (dir == 0) {
    if (x == width - 1) {
      return false;
    } else if (rightWall->at(x)->at(y) == false) {
      return true;
    } else {
      return false;
    }
  } else if (dir == 1) {
    if (y == height - 1) {
      return false;
    } else if (rightWall->at(x)->at(y) == false) {
      return true;
    } else {
      return false;
    }
  } else if (dir == 2) {
    if (x == 0) {
      return false;
    } else if (rightWall->at(x-1)->at(y) == false) {
      return true;
    } else {
      return false;
    }
  } else if (dir == 3) {
    if (y == 0) {
      return false;
    } else if (rightWall->at(x)->at(y-1) == false) {
      return true;
    } else {
      return false;
    }
  } else {
    return false;
  }
}
void SquareMaze::setWall(int x, int y, int dir, bool exists) {
  if (dir == 0) {
    if (exists) {
      rightWall->at(x)->at(y) = true;
    } else {
      rightWall->at(x)->at(y) = false;
    }
  } else {
    if (exists) {
      bottomWall->at(x)->at(y) = true;
    } else {
      bottomWall->at(x)->at(y) = false;
    }
  }
}

std::vector<int> SquareMaze::solveMaze() {
  vector<int> blah;
  blah.push_back(0);
  return blah;
}

cs225::PNG* SquareMaze::drawMaze() const {
  cs225::PNG* maze = new cs225::PNG(width*10 + 1, height*10 + 1);
  cs225::HSLAPixel black(0,0,0);
  // shade in all of left and top
  (*maze).getPixel(0,0) = black;

  for (int i = 10; i < width*10 + 1; i++) {
    (*maze).getPixel(i,0) = black;
  }

  for (int j = 0; j < width*10 + 1; j++) {
    (*maze).getPixel(0,j) = black;
  }

  for (int i = 0; i < width; i++) {
    for (int j = 0; j < height; i++) {
      if (!canTravel(i,j,0)) {
        for (int k = 0; k < 11; k++) {
          (*maze).getPixel(10*i + 10, 10*j + k) = black;
        }
      }
      if (!canTravel(i,j,1)) {
        for (int k = 0; k < 11; k++) {
          (*maze).getPixel(10*i + k, 10*j + 10) = black;
        }
      }
    }
  }
  return maze;
}
cs225::PNG* SquareMaze::drawMazeWithSolution() {
 return NULL;
}