-- Punch repeat falloff, from Second Wind Boxing
-- trulyagents / Redact Studios
--
-- Players found they could hold jab and stunlock people: a jab took 0.28s to
-- throw again and stunned for 0.25s, so the other boxer never got a turn.
-- I shortened the jab stun, and on top of that the same punch thrown again
-- quickly loses some damage and stun each time. Mixing punches resets it.
-- This runs on the server when a punch reaches its target.

--!strict

local REPEAT_WINDOW = 1.2 -- seconds between throws that still count as "again"
local FALLOFF = 0.15 -- lost per repeat
local FLOOR = 0.4 -- never weaker than this

type Fighter = {
	RepeatMove: string?,
	RepeatCount: number,
	RepeatAt: number,
}

-- returns how hard this punch lands, 1 is full strength
local function freshness(attacker: Fighter, move: string, isSpecial: boolean): number
	-- specials are built as chains on purpose, leave them alone
	if isSpecial then
		return 1
	end
	local now = os.clock()
	if attacker.RepeatMove == move and now - attacker.RepeatAt < REPEAT_WINDOW then
		attacker.RepeatCount += 1
	else
		attacker.RepeatMove = move
		attacker.RepeatCount = 0
	end
	attacker.RepeatAt = now
	return math.max(FLOOR, 1 - FALLOFF * attacker.RepeatCount)
end

-- in the hit code:
--   local fresh = freshness(attacker, baseMoveName, move.Special == true)
--   damage *= fresh
--   stun(target, move.Hitstun * fresh)

-- and a test I run before every push, so no basic punch can stunlock again:
--   for name, move in Config.Moves do
--       if not move.Special then
--           assert(move.Hitstun < move.Startup + move.Recovery - 0.05, name .. " can stunlock")
--       end
--   end

return freshness