VoxeLibre/mods/ITEMS/mcl_potions/functions.lua

local is_invisible = {}
local is_poisoned = {}
local is_regenerating = {}
local is_strong = {}
local is_weak = {}
local is_water_breathing = {}
local is_leaping = {}
local is_swift = {}
local is_cat = {}
local is_fire_proof = {}

local is_fire_node = {  ["mcl_core:lava_flowing"]=true,
						["mcl_core:lava_source"]=true,
						["mcl_fire:eternal_fire"]=true,
						["mcl_fire:fire"]=true,
						["mcl_nether:magma"]=true,
						["mcl_nether:nether_lava_source"]=true,
						["mcl_nether:nether_lava_flowing"]=true,
						["mcl_nether:nether_lava_source"]=true}

minetest.register_globalstep(function(dtime)

	-- Check for invisible players
	for player, vals in pairs(is_invisible) do

		if is_invisible[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_invisible[player].timer = is_invisible[player].timer + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#B0B0B0") end

			if is_invisible[player].timer >= is_invisible[player].dur then
				mcl_potions.make_invisible(player, false)
				is_invisible[player] = nil
			end

		elseif not player:get_properties() then
			is_invisible[player] = nil
		end

	end

	-- Check for poisoned players
	for player, vals in pairs(is_poisoned) do

		if is_poisoned[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_poisoned[player].timer = is_poisoned[player].timer + dtime
			is_poisoned[player].hit_timer = (is_poisoned[player].hit_timer or 0) + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#225533") end

			if is_poisoned[player].hit_timer >= is_poisoned[player].step then

				if player._cmi_is_mob then
					player.health = math.max(player.health - 1, 1)
				else
					player:set_hp( math.max(player:get_hp() - 1, 1), { type = "punch", from = "potion" })
				end

				is_poisoned[player].hit_timer = 0

			end

			if is_poisoned[player].timer >= is_poisoned[player].dur then
				is_poisoned[player] = nil
			end

		elseif not player:get_properties() then
			is_poisoned[player] = nil
		end

	end

	-- Check for regnerating players
	for player, vals in pairs(is_regenerating) do

		if is_regenerating[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_regenerating[player].timer = is_regenerating[player].timer + dtime
			is_regenerating[player].heal_timer = (is_regenerating[player].heal_timer or 0) + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#A52BB2") end

			if is_regenerating[player].heal_timer >= is_regenerating[player].step then
				player:set_hp(math.min(player:get_properties().hp_max or 20, player:get_hp() + 1))
				is_regenerating[player].heal_timer = 0
			end

			if is_regenerating[player].timer >= is_regenerating[player].dur then
				is_regenerating[player] = nil
			end

		elseif not player:get_properties() then
			is_regenerating[player] = nil
		end

	end

	-- Check for water breathing players
	for player, vals in pairs(is_water_breathing) do

		if is_water_breathing[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_water_breathing[player].timer = is_water_breathing[player].timer + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#0000AA") end

			if player:get_breath() then
				if player:get_breath() < 10 then player:set_breath(10) end
			end

			if is_water_breathing[player].timer >= is_water_breathing[player].dur then
				is_water_breathing[player] = nil
			end

		elseif not player:get_properties() then
			is_water_breathing[player] = nil
		end

	end

	-- Check for leaping players
	for player, vals in pairs(is_leaping) do

		if is_leaping[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_leaping[player].timer = is_leaping[player].timer + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#00CC33") end

			if is_leaping[player].timer >= is_leaping[player].dur then
				playerphysics.remove_physics_factor(player, "jump", "mcl_potions:leaping")
				is_leaping[player] = nil
			end

		elseif not player:get_properties() then
			is_leaping[player] = nil
		end

	end

	-- Check for swift players
	for player, vals in pairs(is_swift) do

		if is_swift[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_swift[player].timer = is_swift[player].timer + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#009999") end

			if is_swift[player].timer >= is_swift[player].dur then
				playerphysics.remove_physics_factor(player, "speed", "mcl_potions:swiftness")
				is_swift[player] = nil
			end

		elseif not player:get_properties() then
			is_swift[player] = nil
		end

	end

	-- Check for Night Vision equipped players
	for player, vals in pairs(is_cat) do

		if is_cat[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_cat[player].timer = is_cat[player].timer + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#1010AA") end
			player:override_day_night_ratio(0.45)

			if is_cat[player].timer >= is_cat[player].dur then
				is_cat[player] = nil
			end

		elseif not player:get_properties() then
			is_cat[player] = nil
		end

	end

	-- Check for Fire Proof players
	for player, vals in pairs(is_fire_proof) do

		if is_fire_proof[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_fire_proof[player].timer = is_fire_proof[player].timer + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#E0B050") end

			if is_fire_proof[player].timer >= is_fire_proof[player].dur then
				is_fire_proof[player] = nil
			end

		elseif not player:get_properties() then
			is_fire_proof[player] = nil
		end

	end

	-- Check for Weak players
	for player, vals in pairs(is_weak) do

		if is_weak[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_weak[player].timer = is_weak[player].timer + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#7700BB") end

			if is_weak[player].timer >= is_weak[player].dur then
				is_weak[player] = nil
			end

		elseif not player:get_properties() then
			is_weak[player] = nil
		end

	end

	-- Check for Strong players
	for player, vals in pairs(is_strong) do

		if is_strong[player] and player:get_properties() then

			player = player or player:get_luaentity()

			is_strong[player].timer = is_strong[player].timer + dtime

			if player:get_pos() then mcl_potions._add_spawner(player, "#7700BB") end

			if is_strong[player].timer >= is_strong[player].dur then
				is_strong[player] = nil
			end

		elseif not player:get_properties() then
			is_strong[player] = nil
		end

	end

end)

-- Prevent damage to player with Fire Resistance enabled
minetest.register_on_player_hpchange(function(player, hp_change)

	if is_fire_proof[player] and hp_change < 0 then
		-- This is a bit forced, but it assumes damage is taken by fire and avoids it
		-- also assumes any change in hp happens between calls to this function
		-- it's worth noting that you don't take damage from players in this case...
		local player_info = mcl_playerinfo[player:get_player_name()]

		if is_fire_node[player_info.node_head] or is_fire_node[player_info.node_feet] or is_fire_node[player_info.node_stand] then
			if player:get_breath() == 0 then -- probably drowning
				return -1
			else
				return 0
			end
		else
			return hp_change
		end

	else
		return hp_change
	end

end, true)


-- -- If a player is punched and is a weak player, damage by 2 additional hearts
-- minetest.register_on_player_hpchange(function(player, hp_change)
--
-- 	if is_weak[player] and hp_change < 0 then
--
-- 		-- prevent weakness from healing the victim
-- 		return math.min(hp_change - 4, 0)
--
-- 	else
-- 		return hp_change
-- 	end
--
-- end, true)


function mcl_potions._reset_player_effects(player)

	player = player or player:get_luaentity()

	if is_invisible[player] then
		mcl_potions.make_invisible(player, false)
		is_invisible[player] = nil
	end

	if is_poisoned[player] then
		is_poisoned[player] = nil
	end

	if is_regenerating[player] then
		is_regenerating[player] = nil
	end

	if is_strong[player] then
		is_strong[player] = nil
	end

	if is_weak[player] then
		is_weak[player] = nil
	end

	if is_water_breathing[player] then
		is_water_breathing[player] = nil
	end

	if is_leaping[player] then
		is_leaping[player] = nil
		playerphysics.remove_physics_factor(player, "jump", "mcl_potions:leaping")
	end

	if is_swift[player] then
		is_swift[player] = nil
		playerphysics.remove_physics_factor(player, "speed", "mcl_potions:swiftness")
	end

	if is_cat[player] then
		is_cat[player] = nil
	end

	if is_fire_proof[player] then
		is_fire_proof[player] = nil
	end

end

minetest.register_on_leaveplayer( function(player) mcl_potions._reset_player_effects(player) end)
minetest.register_on_dieplayer( function(player) mcl_potions._reset_player_effects(player) end)

function mcl_potions.is_obj_hit(self, pos)

	for _,object in pairs(minetest.get_objects_inside_radius(pos, 1.1)) do

		local entity = object:get_luaentity()

		if entity and entity.name ~= self.object:get_luaentity().name then

			if object:is_player() or entity._cmi_is_mob then return true end

		end

	end
	return false
end


function mcl_potions.make_invisible(player, toggle)

	if not player then return false end

	if toggle then -- hide player
		is_invisible[player].old_size = player:get_properties().visual_size
		player:set_properties({visual_size = {x = 0, y = 0}})
		player:set_nametag_attributes({color = {a = 0}})
	else -- show player
		player:set_properties({visual_size = is_invisible[player].old_size})
		player:set_nametag_attributes({color = {a = 255}})
	end

end

function mcl_potions.poison(player, toggle)

	if not player then return false end
	is_poisoned[player:get_player_name()] = toggle

end

function mcl_potions.regenerate(player, toggle)

	if not player then return false end
	is_regenerating[player:get_player_name()] = toggle

end

function mcl_potions._use_potion(item, obj, color)
	local d = 0.1
	local pos = obj:get_pos()
	minetest.sound_play("mcl_potions_drinking", {pos = pos, max_hear_distance = 6, gain = 1})
	minetest.add_particlespawner({
									amount = 25,
									time = 1,
									minpos = {x=pos.x-d, y=pos.y+1, z=pos.z-d},
									maxpos = {x=pos.x+d, y=pos.y+2, z=pos.z+d},
									minvel = {x=-0.1, y=0, z=-0.1},
									maxvel = {x=0.1, y=0.1, z=0.1},
									minacc = {x=-0.1, y=0, z=-0.1},
									maxacc = {x=0.1, y=.1, z=0.1},
									minexptime = 1,
									maxexptime = 5,
									minsize = 0.5,
									maxsize = 1,
									collisiondetection = true,
									vertical = false,
									texture = "mcl_potions_sprite.png^[colorize:"..color..":127",
								})
end


function mcl_potions._add_spawner(obj, color)
	local d = 0.2
	local pos = obj:get_pos()
	minetest.add_particlespawner({
									amount = 2,
									time = 1,
									minpos = {x=pos.x-d, y=pos.y+1, z=pos.z-d},
									maxpos = {x=pos.x+d, y=pos.y+2, z=pos.z+d},
									minvel = {x=-0.1, y=0, z=-0.1},
									maxvel = {x=0.1, y=0.1, z=0.1},
									minacc = {x=-0.1, y=0, z=-0.1},
									maxacc = {x=0.1, y=.1, z=0.1},
									minexptime = 0.5,
									maxexptime = 1,
									minsize = 0.5,
									maxsize = 1,
									collisiondetection = false,
									vertical = false,
									texture = "mcl_potions_sprite.png^[colorize:"..color..":127",
								})
end


local is_zombie = {}

for i, zombie in ipairs({"husk","zombie","pigman"}) do
	is_zombie["mobs_mc:"..zombie] = true
	is_zombie["mobs_mc:baby_"..zombie] = true
end

function mcl_potions.healing_func(player, hp)

	obj = player:get_luaentity()

	if is_zombie[player:get_entity_name()] then hp = -hp end

	if hp > 0 then

		if obj and obj._cmi_is_mob then
			obj.health = math.max(obj.health + hp, obj.hp_max)
		else
			player:set_hp(math.min(player:get_hp() + hp, player:get_properties().hp_max))
		end

	else

		if obj and obj._cmi_is_mob then
			obj.health = obj.health + hp
		else
			player:set_hp(player:get_hp() + hp, { type = "punch", from = "potion" })
		end

	end

	-- adjust mob health
	obj = player:get_luaentity()
	if obj and obj._cmi_is_mob then
		obj.health = obj.health + hp
	end

end

function mcl_potions.swiftness_func(player, factor, duration)

	if not player:get_meta() then return false end

	if not is_swift[player] then

		is_swift[player] = {dur = duration, timer = 0}
		playerphysics.add_physics_factor(player, "speed", "mcl_potions:swiftness", factor)

	else

		local victim = is_swift[player]

		playerphysics.add_physics_factor(player, "speed", "mcl_potions:swiftness", factor)
		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end

end

function mcl_potions.leaping_func(player, factor, duration)

	if not player:get_meta() then return false end

	if not is_leaping[player] then

		is_leaping[player] = {dur = duration, timer = 0}
		playerphysics.add_physics_factor(player, "jump", "mcl_potions:leaping", factor)

	else

		local victim = is_leaping[player]

		playerphysics.add_physics_factor(player, "jump", "mcl_potions:leaping", factor)
		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end

end


function mcl_potions.weakness_func(player, factor, duration)

	if not is_weak[player] then

		is_weak[player] = {dur = duration, timer = 0, factor = factor}

	else

		local victim = is_weak[player]

		victim.factor = factor
		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end

end


function mcl_potions.strength_func(player, factor, duration)

	if not is_strong[player] then

		is_strong[player] = {dur = duration, timer = 0, factor = factor}

	else

		local victim = is_strong[player]

		victim.factor = factor
		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end

end


function mcl_potions.poison_func(player, factor, duration)

	if not is_poisoned[player] then

		is_poisoned[player] = {step = factor, dur = duration, timer = 0}

	else

		local victim = is_poisoned[player]

		victim.step = math.min(victim.step, factor)
		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end
end


function mcl_potions.regeneration_func(player, factor, duration)

	if not is_regenerating[player] then

		is_regenerating[player] = {step = factor, dur = duration, timer = 0}

	else

		local victim = is_regenerating[player]

		victim.step = math.min(victim.step, factor)
		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end
end


function mcl_potions.invisiblility_func(player, duration)

	if not is_invisible[player] then

		is_invisible[player] = {dur = duration, timer = 0}
		mcl_potions.make_invisible(player, true)

	else

		local victim = is_invisible[player]

		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end

end

function mcl_potions.water_breathing_func(player, duration)

	if not is_water_breathing[player] then

		is_water_breathing[player] = {dur = duration, timer = 0}

	else

		local victim = is_water_breathing[player]

		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end

end


function mcl_potions.fire_resistance_func(player, duration)

	if not is_fire_proof[player] then

		is_fire_proof[player] = {dur = duration, timer = 0}

	else

		local victim = is_fire_proof[player]
		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end

end


function mcl_potions.night_vision_func(player, duration)

	if not is_cat[player] then

		is_cat[player] = {dur = duration, timer = 0}

	else

		local victim = is_cat[player]

		victim.dur = math.max(duration, victim.dur - victim.timer)
		victim.timer = 0

	end

end