Module:Calc/User:Galvagornus

Documentation for this module may be created at Module:Calc/User:Galvagornus/doc

local p = {}

function expr(x)
	x = tostring(x)
	local expr_good, expr_val = pcall(mw.ext.ParserFunctions.expr, x)
	if expr_good then
		return tonumber(expr_val)
	end
	return nil
end

-- from WP
function choose(n,k)
	if k < 0 or k > n then
		return 0
	end
	if k == 0 or k == n then
		return 1
	end
	k = math.min(k, n-k) -- symmetry
	c = 1
	for i=0,k-1 do
		c = c * (n-i) / (k - i)
	end
	return c
end

function flavourText(x)
	local flavourTexts = {
		{ -1, 1, "You are some sort of sentient water being you're so not-dry. How'd you even do this?" },
		{ 1, 10, "You're a higher % water than a watermelon." },
		{ 10, 20, "Only ironmen can be this lucky." },
		{ 20, 30, "Spooned." },
		{ 30, 40, "Your friends will be jealous." },
		{ 40, 49, "You're quite the lucker aren't you." },
		{ 49, 51, "A perfect mix of dry and undry, as all things should be." },
		{ 51, 61, 'Nothing interesting happens.' },
		{ 61, 65, "An unenlightened being would say 'but 1/x over x kills means I should get it', but you know better now." },
		{ 65, 73, 'Nothing interesting happens.' },
		{ 73, 74, "😂😂😂" },
		{ 74, 85, "oof" },
		{ 85, 90, "A national emergency has been declared in your drop log." },
		{ 90, 95, "Right, time to post on reddit." },
		{ 95, 99, "You after being this dry: [[File:Skeleton.png|80x80px]]" },
		{ 99, 99.5, "You are so dry you have collapsed into the dry singularity. The dryularity, if you will." },
		{ 99.5, 99.9, "The vacuum of space has more activity than your drop log." },
		{ 99.9, 99.99, "Wow that's so rare! Seems like it's bugged. We tweeted @JagexAsh for you, we're sure he'll get to the bottom of it in the next 24 hours." },
		{ 99.99, 1000, "Did you forget to talk to [[Oziach]]?" }
	}
	for i,v in ipairs(flavourTexts) do
		if x >= v[1] and x <= v[2] then
			return v[3]
		end
	end
	return ''
end

function p.main(frame)
	local args = frame.args
	return p.calc(args.chance, args.kills, args.dropped)
end

function p.calc(chanceTxt, kc, obtained)
	local chance = expr(chanceTxt)
	if not chance then
		return 'Looks like there was an error with your input chance, try typing it in again'
	else
		if chance > 1 then
			return "You put your chance at over 1 you absolute madman"
		elseif chance <= 0 then
			return "You put your chance at 0 or negative, how you gonna get that drop?"
		end
	end
	local notchance = 1 - chance
		
	
	kc = tonumber(kc)
	if not kc or kc == 0 then
		return "You ain't killed anything you crazy fool"
	end
	obtained = tonumber(obtained) or 0
	
	if kc < obtained then
		return "?????"
	end
	
	if choose(kc, obtained) == 1/0 then -- Check if we can handle these values
		return "Sorry, your killcount and obtained number combination is too large for this calculator. Try reducing your numbers."
	end
	
	local luck = 0.0
	for i=0, obtained do
		luck = luck + choose(kc, i) * math.pow(chance, i) * math.pow(1-chance, kc-i)
	end
	return string.format("You killed %s monsters for an item with a %s (%.6f%%) drop chance. You had a:\n* %.4f%% chance of getting %s drops or fewer\n* %.4f%% chance of getting more than %s drops. %s", kc, chanceTxt, 100*chance, 100*luck, obtained, 100*(1.0-luck),obtained, flavourText((1.0-luck)*100))

end

return p