import time

class SearchStats:
    def __init__(self, time_ms, visited_cells, path_length):
        self.time_ms = time_ms
        self.visited_cells = visited_cells
        self.path_length = path_length

    def __str__(self):
        return (f"Время: {self.time_ms:.3f} мс\n"
                f"Посещено клеток: {self.visited_cells}\n"
                f"Длина пути: {self.path_length}")


class MazeSolver:
    def __init__(self, maze, strategy):
        self.maze = maze
        self.strategy = strategy
        self.observers = []

    def setStrategy(self, strategy):
        self.strategy = strategy

    def solve(self):
        self.notify("Начат поиск")
        
        start_time = time.perf_counter()
        path, visited = self.strategy.findPath(self.maze, self.maze.start, self.maze.exit)
        end_time = time.perf_counter()
        
        self.notify("Путь найден")
        
        time_ms = (end_time - start_time) * 1000
        stats = SearchStats(time_ms, visited, len(path))
        return stats

    def addObserver(self, observer):
        self.observers.append(observer)

    def notify(self, event):
        for observer in self.observers:
            observer.update(event)