Rotting Oranges

def orangesRotting(grid):
    q = collections.deque()
    time, fresh = 0, 0
    ROWS, COLS = len(grid), len(grid[0])
    
    for r in range(ROWS):
        for c in range(COLS):
            if grid[r][c] == 1:
                fresh += 1
            if grid[r][c] == 2:
                q.append([r, c])
                
    directions = [[0, 1], [0, -1], [1, 0], [-1, 0]]
    while q and fresh > 0:
        for i in range(len(q)):
            r, c = q.popleft()
            for dr, dc in directions:
                row, col = r + dr, c + dc
                if (row < 0 or row == ROWS or col < 0 or col == COLS or
                    grid[row][col] != 1):
                    continue
                grid[row][col] = 2
                q.append([row, col])
                fresh -= 1
        time += 1
        
    return time if fresh == 0 else -1