<think>
Okay, I need to implement the score_scale function. Let's see the requirements. The function takes a mark, the original total (was_out_of), and the new total (now_out_of). The goal is to restate the mark as a new score out of now_out_of, rounded down. Also, if the original mark is above the was_out_of, it can't pass the new total. And if the new total is zero, the mark is nothing.

First, I need to calculate the proportion of the original mark relative to the original total. But since it's scaled down, I should do a division and then floor it. Wait, but how exactly?

Wait, the problem says that a mark standing above the total it was given out of still cannot pass the new total. So if the original mark is higher than was_out_of, then the new mark is zero? Or maybe the original mark is supposed to be a value between 0 and was_out_of. So if the original mark is higher than was_out_of, it's treated as was_out_of? Or maybe the function is supposed to take the original mark as a value that's within 0 to was_out_of. But the problem says that if the original mark is above the total, it can't pass the new total. So maybe the first step is to cap the original mark at was_out_of. Because if the original mark is higher than was_out_of, then it's considered as was_out_of. But the problem says "a mark standing above the total it was given out of still cannot pass the new total", so maybe the original mark is clamped to was_out_of if it's higher. Wait, but the problem says "a total of nothing to scale from gives a mark of nothing". So if was_out_of is zero, then the mark is zero. But if was_out_of is non-zero, then the original mark is clamped to was_out_of if it's higher?

Wait, the problem says that the mark is given out of one total. So the original mark is between 0 and was_out_of. But if the original mark is higher than was_out_of, then it's considered as was_out_of? Or maybe the original mark is supposed to be a valid value, so the function is supposed to handle cases where the original mark is invalid. But the problem says that if the original mark is above the total, it can't pass the new total. So perhaps the first step is to take the original mark and cap it at was_out_of. Because if the original mark is higher than was_out_of, then it's treated as was_out_of. But how?

Wait, the problem says that the mark is given out of one total. So the original mark is a value that is between 0 and was_out_of. But if the original mark is higher than was_out_of, then it's considered as was_out_of. So the first step is to take the original mark and clamp it to the range [0, was_out_of]. Because if the original mark is higher than was_out_of, then it's treated as was_out_of. But the problem says that a mark standing above the total it was given out of still cannot pass the new total. So maybe the original mark is clamped to was_out_of if it's higher. So the first step is to take the original mark and set it to min(mark, was_out_of). But also, if the original mark is negative, what happens? The problem says that a mark below zero should scale in the same way is not stated. But the problem says that if the total to scale from is zero, then the mark is nothing. But for other cases, maybe the original mark is clamped to 0