Chess clock flag fall

Replay the thinking times of a chess game on a Fischer-increment clock and report who, if anyone, lost on time.

Both players start with base seconds on their clock. White moves first and the players alternate. spent[i] is how many seconds the player making half-move i + 1 kept their own clock running for that move.

When a player makes a move:

• Their clock goes down by the seconds spent. If it reaches 0 or below, they have flagged and the game ends at once; nothing is added to a clock that has flagged.
• Otherwise increment seconds are added to their clock.
• Then, if this was that player's bonusMove-th move, bonus extra seconds are also added to their clock. Each player gets the bonus after their own bonusMove-th move (not after the bonusMove-th half-move of the game).

Moves are numbered the way chess players do: White's and Black's first moves are both move 1, their second moves are move 2, and so on.

Input: base, increment, bonusMove and bonus as integers, and spent, a list of integers.

Output: a string. If a player flagged, return "flag W n" or "flag B n", where n is their move number. If everyone survives all of spent, return "clocks w b" with White's and then Black's remaining seconds.