#include "script/common.lua"

local MIN_RADIUS = 0.3
local MAX_RADIUS = 8
local ROT_SPEED = 5
local HEIGHT = 30
local MIN_SPAWN_DIST_TO_PLAYER = 10

local SUCK_RADIUS = 12

function rnd(mi, ma)
	return math.random(1000)/1000*(ma-mi) + mi
end

function rndVec(t)
	return Vec(rnd(-t, t), rnd(-t, t), rnd(-t, t))
end

tornado = {}
tornado.pos = Vec()
tornado.age = 0
tornado.lifetime = 0
tornado.spawnAngle = 0
tornado.active = false
tornado.trail = false

function init()
	tornadoSnd = LoadLoop("tornado.ogg")
	triggers = FindTriggers()
end

function spawn(startPos, endPos, lifetime)
	tornado.startPos = startPos
	tornado.endPos = endPos
	tornado.age = 0
	tornado.lifetime = lifetime
	tornado.spawnAngle = 0
	tornado.pos = startPos
	tornado.active = true
	tornado.trail = true
end

function tick(dt)
end

function mix(lo, hi, t)
	return lo+(hi-lo)*t
end

function getOffset(relativeHeight)
	local bigAng = tornado.age * 1 + relativeHeight*8
	local bend = math.sin(relativeHeight*math.pi) * 3 -- Bend only in the middle
	return Vec(math.sin(bigAng)*bend, 0, math.sin(bigAng*0.7)*bend)
end

function TornadSpawnParticlesLUA(tornadoSpawnAngle, height, minRadius, maxRadius, rotSpeed, tornadoPos, tornadoAmount, tornadoAge, tornadoTrail)

	ParticleReset()
	ParticleType("plain")
	ParticleTile(0)
	ParticleCollide(0)
	local count = 64
	tornado.spawnAngle = tornadoSpawnAngle + 2.39996
	local spawnAngle = tornadoSpawnAngle
	for i=0, count do
		local hh = i/count
		hh = hh * hh * hh * hh -- Need to spawn more particles at bottom
		local q = 1.0-hh
		local h = height * hh
		spawnAngle = spawnAngle + 2.39996 --Golden angle
		local ang =  spawnAngle
		local r = mix(minRadius, maxRadius, hh*hh) * rnd(0.7, 1.3)
		local v = rotSpeed
		local lifetime = 2/(v/r)

		--Position and velocity
		local pos = VecAdd(tornadoPos, Vec(math.cos(ang)*r, h, math.sin(ang)*r))
		local offset = getOffset(hh)
		pos = VecAdd(pos, offset)
		local vel = Vec(-math.sin(ang)*v, v*q, math.cos(ang)*v)

		--Particle properties
		local col = rnd(0.7, 1.0)
		ParticleColor(col, 0.9*col, 0.8*col)
		ParticleRadius(0.4 + r*0.4)
		ParticleAlpha(q*tornadoAmount, 0, "constant", 0.25, 0.5)

		--Spawn
		SpawnParticle(pos, vel, lifetime)
	end
	if tornadoTrail then
		ParticleReset()
		ParticleCollide(0)
		ParticleType("smoke")
		ParticleAlpha(tornadoAmount, 0)
		ParticleTile(0)
		ParticleColor(0.9, 0.85, 0.8)
		ParticleDrag(0.5)
		for i=1, 4 do
			ParticleRadius(0.2, rnd(0.3, 0.6))
			SpawnParticle(VecAdd(tornado.pos, Vec(rnd(-0.2, 0.2), rnd(0.1, 0.2), rnd(-0.2, 0.2))), Vec(rnd(-10, 10), rnd(-2, 2), rnd(-10, 10)), rnd(1.0, 3.0))
		end
	end
	ParticleReset()
	ParticleType("plain")
	ParticleAlpha(tornadoAmount, 0)
	ParticleTile(6)
	ParticleColor(0.4, 0.4, 0.4)
	ParticleDrag(0.05)
	ParticleCollide(1.0)
	for i=1,4 do
		ParticleGravity(-10)
		ParticleRadius(rnd(0.01, 0.03))
		SpawnParticle(VecAdd(tornadoPos, rndVec(0.1)), Vec(rnd(-5,5), rnd(2, 10), rnd(-5,5)), rnd(0.5, 1.5))
	end
	
end

function emitParticles()

	tornado.spawnAngle = tornado.spawnAngle + 2.39996
	--TornadSpawnParticlesLUA(tornado.spawnAngle, HEIGHT, MIN_RADIUS, MAX_RADIUS, ROT_SPEED, tornado.pos, tornado.amount, tornado.age, tornado.trail)
	TornadoSpawnParticlesCPP(tornado.spawnAngle, HEIGHT, MIN_RADIUS, MAX_RADIUS, ROT_SPEED, tornado.pos, tornado.amount, tornado.age, tornado.trail)
	
end

function destroy()
	local h = rnd(0.0, 8.0)
	local pos = VecAdd(tornado.pos, getOffset(h/HEIGHT))
	pos[2] = pos[2] + h
	MakeHole(pos, 1.0, 0.5, 0, true)
end

function getVelForBody(pos, mass, vel, angVel)
	--Closest point on tornado
	local tornadoPoint = VecCopy(tornado.pos)
	tornadoPoint[2] = pos[2]
	local tornadoHeight = clamp((tornadoPoint[2] - tornado.pos[2])/HEIGHT, 0.0, 1.0)
	tornadoPoint = VecAdd(tornadoPoint, getOffset(tornadoHeight))
	
	local toTornado = VecSub(tornadoPoint, pos)
	local dist = VecLength(toTornado)
	if dist > 0.0 then
		toTornado = VecScale(toTornado, 1.0 / dist)
	end
	
	if dist < SUCK_RADIUS then
		local strength = 1.0 - dist/SUCK_RADIUS
		strength = strength * (1-tornadoHeight) 
		strength = strength * strength
		strength = strength * 3.0 * tornado.amount
		strength = strength * 1000 / (1000+mass)
		
		local addVel = VecScale(toTornado, strength)
		addVel[2] = strength * 0.5
		local perp = Vec(toTornado[3], 0.0, -toTornado[1])
		addVel = VecAdd(addVel, VecScale(perp, strength*0.2))
		local maxVel = 8
		
		for i=1, 3 do
			if addVel[i] < 0 and vel[i] < -maxVel then addVel[i]=0 end
			if addVel[i] > 0 and vel[i] > maxVel then addVel[i]=0 end
		end

		local maxAngVel = 5
		local addAngVel = -ROT_SPEED * strength * 0.05
		if angVel[2] < -maxAngVel then addAngVel = 0 end
		return VecAdd(vel, addVel), VecAdd(angVel, Vec(0, addAngVel, 0))
	else 
		return vel, angVel
	end
end

function TornadoBodiesSuctionLUA(lo, hi)

	QueryRequire("dynamic")
	local bodies = QueryAabbBodies(lo, hi)
	for i=1, #bodies do
		local body = bodies[i]
		local bodyPos = TransformToParentPoint(GetBodyTransform(body), GetBodyCenterOfMass(body))
		local vel, angVel = getVelForBody(bodyPos, GetBodyMass(body), GetBodyVelocity(body), GetBodyAngularVelocity(body))
		SetBodyVelocity(body, vel)
		SetBodyAngularVelocity(body, angVel)
	end
	
end


function suction()
	local lo = VecAdd(tornado.pos, Vec(-SUCK_RADIUS, 0, -SUCK_RADIUS))
	local hi = VecAdd(tornado.pos, Vec(SUCK_RADIUS, HEIGHT, SUCK_RADIUS))

	--TornadoBodiesSuctionLUA(lo, hi)
	TornadoBodiesSuctionCPP(tornado.pos, tornado.amount, tornado.age, HEIGHT,SUCK_RADIUS, ROT_SPEED, lo, hi)
	
	--Affect player
	if GetPlayerVehicle() == 0 and not GetBool("game.map.enabled") then
		local ppos = GetPlayerTransform().pos
		ppos[2] = ppos[2] + 1.0 -- Chest height
		local tpos = VecCopy(tornado.pos)
		tpos[2] = ppos[2]		-- Same height on tornado
		local diff = VecSub(tpos, ppos)
		local length = VecLength(diff)
		if length > 0 and length < SUCK_RADIUS then
			local toTornado = VecScale(diff, 1.0/length)
			QueryRequire("static")
			local hit = QueryRaycast(ppos, toTornado, length)
			if not hit then
				if length < 3 then
					ReleasePlayerGrab()
				end
			
				ShakeCamera(1.0 - length/SUCK_RADIUS)

				--Make player approach tornado when on ground
				local strength = math.pow(1.0 - length / SUCK_RADIUS, 0.5) * 8.0 * tornado.amount;
				SetPlayerGroundVelocity(VecScale(toTornado, strength))

				--Modify player velocity
				local vel = getVelForBody(ppos, 2000, GetPlayerVelocity(), Vec())
				SetPlayerVelocity(vel)
			end
		end
	end
end

function spawnTornadoInTrigger(trigger)
	local mi, ma = GetTriggerBounds(trigger)
	local p1, p2

	local minDist = math.max(ma[1]-mi[1], ma[3]-mi[3])*0.25
	minDist = math.min(minDist, 5.0)

	for i=1, 100 do
		local probe = Vec()
		for j=1, 3 do
			probe[j] = mi[j] + (ma[j]-mi[j])*rnd(0,1)
		end
		if IsPointInTrigger(trigger, probe) then
			local ppos = GetPlayerTransform().pos
			ppos[2] = probe[2]
			if not p1 and VecLength(VecSub(probe, ppos)) > MIN_SPAWN_DIST_TO_PLAYER then
				p1 = probe
				p1[2] = mi[2]
			else
				if VecLength(VecSub(probe, p1)) > minDist then
					p2 = probe
					p2[2] = mi[2]
					break
				end
			end
		end
	end
	if p1 and p2 then
		spawn(p1, p2, 10)
	end
end

function spawnTornado()
	local ppos = TransformToParentPoint(GetPlayerTransform(), Vec(0, 0, -16))
	DebugCross(ppos)
	ppos[2] = 0
	local bestLength = 1000000
	local bestTrigger = nil
	for i=1, #triggers do
		local mi, ma = GetTriggerBounds(triggers[i])
		local pos = VecLerp(mi, ma, 0.5)
		pos[2] = 0
		local l = VecLength(VecSub(ppos, pos))
		if l<bestLength then
			bestLength = l
			bestTrigger = triggers[i]
		end
	end
	if bestTrigger then
		spawnTornadoInTrigger(bestTrigger)
	end
end

function update(dt)
	if tornado.active then
		tornado.pos = VecLerp(tornado.startPos, tornado.endPos, tornado.age/tornado.lifetime)
		local fadeIn = 3
		local fadeOut = 3
		if tornado.age < fadeIn	then 
			tornado.amount = tornado.age/fadeIn
		elseif tornado.lifetime-tornado.age < fadeOut then
			tornado.amount = (tornado.lifetime-tornado.age)/fadeOut
		else
			tornado.amount = 1.0
		end
		tornado.amount = tornado.amount*tornado.amount
		PlayLoop(tornadoSnd, tornado.pos, tornado.amount * 3)
	
		tornado.pos[1] = tornado.pos[1] + 0.03
		tornado.pos[3] = tornado.pos[3] + 0.03
		--destroy()
		suction()
		emitParticles()
	
		tornado.age = tornado.age + dt
		if tornado.age > tornado.lifetime then
			tornado.active = false
		end
	else
		spawnTornado()
	end
	
end