Can Place Flowers

class Solution:
    def canPlaceFlowers(self, flowerbed: List[int], n: int) -> bool:
        # In case of invalid input, return False
        if n < 0:
            return False

        if len(flowerbed) == 0:
            return n == 0

        # Handle case of single flower explicitely so that i + 1 logic in the next
        # section of code works, else throws array index out of bound error
        if len(flowerbed) == 1:
            return (flowerbed[0] == 1 and n == 0) or (flowerbed[0] == 0 and n <= 1)

        l = len(flowerbed)

        # will store the count of flowers placed so far
        placed = 0

        # whether we have seen one flower in the previous index or not
        prev_seen = False

        for i in range(l - 1):
            # If current index is flower
            if flowerbed[i] == 1:
                prev_seen = True
                continue

            # Reached here means current index is not a flower, we check
            # whether previous index was a flower, if yes, we continue but
            # also set previously seen as false because for next index, the
            # current index will stay empty so we can place a flower in the
            # next available index
            if prev_seen:
                prev_seen = False
                continue

            # This is an empty location whose previous position is also empty
            prev_seen = False

            # Check if next position has a flower, then simply move on as
            # previous seen will anyway become True in the next iteration
            if flowerbed[i + 1] == 1:
                continue

            # All conditions satisfied, this place can hold a new flower
            placed += 1
            prev_seen = True

        # handle last value explicitely as for loop runs to second last place
        if not prev_seen and flowerbed[l - 1] == 0:
            placed += 1

        # Check for greater than equality, as we might be able to place more
        # flowers than n too, similarly we can solve if the question asks for
        # exactly n flowers, then check for equality only
        return placed >= n