# maze.py – версия 1: модель лабиринта и загрузка из текстового файла

class Cell:
    """Клетка лабиринта."""
    def __init__(self, x, y, is_wall=False, is_start=False, is_exit=False):
        self.x = x
        self.y = y
        self.is_wall = is_wall
        self.is_start = is_start
        self.is_exit = is_exit

    def is_passable(self):
        return not self.is_wall


class Maze:
    """Модель лабиринта."""
    def __init__(self, width, height):
        self.width = width
        self.height = height
        self.grid = [[Cell(x, y) for y in range(height)] for x in range(width)]
        self.start_cell = None
        self.exit_cell = None

    def get_cell(self, x, y):
        if 0 <= x < self.width and 0 <= y < self.height:
            return self.grid[x][y]
        return None

    def get_neighbors(self, cell):
        """Возвращает список проходимых соседей (вверх, вниз, влево, вправо)."""
        neighbors = []
        for dx, dy in [(-1,0), (1,0), (0,-1), (0,1)]:
            nx, ny = cell.x + dx, cell.y + dy
            neighbor = self.get_cell(nx, ny)
            if neighbor and neighbor.is_passable():
                neighbors.append(neighbor)
        return neighbors


class MazeBuilder:
    """Интерфейс строителя лабиринта."""
    def build_from_file(self, filename):
        raise NotImplementedError


class TextFileMazeBuilder(MazeBuilder):
    """Строитель лабиринта из текстового файла."""
    def build_from_file(self, filename):
        with open(filename, 'r', encoding='utf-8') as f:
            lines = f.readlines()
        lines = [line.rstrip('\n') for line in lines if line.strip() != '']
        if not lines:
            raise ValueError("Файл пуст")
        height = len(lines)
        width = max(len(line) for line in lines)
        maze = Maze(width, height)
        for y, line in enumerate(lines):
            for x, ch in enumerate(line):
                if x >= width:
                    break
                cell = maze.get_cell(x, y)
                if ch == '#':
                    cell.is_wall = True
                elif ch == 'S':
                    cell.is_start = True
                    maze.start_cell = cell
                elif ch == 'E':
                    cell.is_exit = True
                    maze.exit_cell = cell
        if maze.start_cell is None or maze.exit_cell is None:
            raise ValueError("В лабиринте должны быть S и E")
        return maze


# Тестирование загрузки
if __name__ == '__main__':
    # Создаём тестовый файл
    test_maze = """#######
#S    #
# ### #
#   E #
#######"""
    with open('test_maze.txt', 'w') as f:
        f.write(test_maze)
    builder = TextFileMazeBuilder()
    maze = builder.build_from_file('test_maze.txt')
    print(f"Лабиринт {maze.width}x{maze.height} загружен.")
    print(f"Старт: ({maze.start_cell.x},{maze.start_cell.y})")
    print(f"Выход: ({maze.exit_cell.x},{maze.exit_cell.y})")
    # Вывод карты
    for y in range(maze.height):
        row = ''
        for x in range(maze.width):
            cell = maze.get_cell(x, y)
            if cell.is_wall:
                row += '#'
            elif cell.is_start:
                row += 'S'
            elif cell.is_exit:
                row += 'E'
            else:
                row += ' '
        print(row)