throwing = {}

throwing.arrows = {}

throwing.target_object = 1
throwing.target_node = 2
throwing.target_both = 3

throwing.modname = minetest.get_current_modname()

--------- Arrows functions ---------
function throwing.is_arrow(itemstack)
	for _, arrow in ipairs(throwing.arrows) do
		if (type(itemstack) == "string" and itemstack or itemstack:get_name()) == arrow then
			return true
		end
	end
	return false
end

function throwing.spawn_arrow_entity(pos, arrow, player)
	if throwing.is_arrow(arrow) then
		return minetest.add_entity(pos, arrow.."_entity")
	elseif minetest.registered_items[arrow].throwing_entity then
		if type(minetest.registered_items[arrow].throwing_entity) == "string" then
			return minetest.add_entity(pos, minetest.registered_items[arrow].throwing_entity)
		else -- Type is a function
			return minetest.registered_items[arrow].throwing_entity(pos, player)
		end
	else
		obj = minetest.add_entity(pos, "__builtin:item", arrow)
	end
end

local function shoot_arrow(itemstack, player, index, throw_itself, new_stack)
	local inventory = player:get_inventory()
	if not throw_itself then
		if index >= player:get_inventory():get_size("main") then
			return false
		end
		index = index + 1
	end
	local arrow_stack = inventory:get_stack("main", index)
	local arrow = arrow_stack:get_name()

	local playerpos = player:getpos()
	local pos = {x=playerpos.x,y=playerpos.y+1.5,z=playerpos.z}
	local obj = (minetest.registered_items[itemstack:get_name()].spawn_arrow_entity or throwing.spawn_arrow_entity)(pos, arrow, player)

	local luaentity = obj:get_luaentity()
	luaentity.player = player:get_player_name()
	if not luaentity.item then
		luaentity.item = arrow
	end

	if luaentity.on_throw then
		if luaentity:on_throw(pos, player, arrow_stack, index, luaentity.data) == false then
			obj:remove()
			return false
		end
	end

	local dir = player:get_look_dir()
	local velocity_factor = tonumber(minetest.settings:get("throwing.velocity_factor")) or 19
	local horizontal_acceleration_factor = tonumber(minetest.settings:get("throwing.horizontal_acceleration_factor")) or -3
	local vertical_acceleration = tonumber(minetest.settings:get("throwing.vertical_acceleration")) or -10

	obj:setvelocity({x=dir.x*velocity_factor, y=dir.y*velocity_factor, z=dir.z*velocity_factor})
	obj:setacceleration({x=dir.x*horizontal_acceleration_factor, y=vertical_acceleration, z=dir.z*horizontal_acceleration_factor})
	obj:setyaw(player:get_look_horizontal()-math.pi/2)

	if luaentity.on_throw_sound ~= "" then
		minetest.sound_play(luaentity.on_throw_sound or "throwing_sound", {pos=playerpos, gain = 0.5})
	end

	if not minetest.settings:get_bool("creative_mode") then
		if new_stack then
			inventory:set_stack("main", index, new_stack)
		else
			local stack = inventory:get_stack("main", index)
			stack:take_item()
			inventory:set_stack("main", index, stack)
		end
	end

	return true
end

local function arrow_step(self, dtime)
	self.timer = self.timer + dtime
	local pos = self.object:getpos()
	local node = minetest.get_node(pos)

	local logging = function(message, level)
		minetest.log(level or "action", "[throwing] Arrow "..self.item or self.name.." throwed by player "..self.player.." "..tostring(self.timer).."s ago "..message)
	end

	local hit = function(pos, node, obj)
		if obj then
			if obj:is_player() then
				if obj:get_player_name() == self.player then -- Avoid hitting the hitter
					return false
				end
			end
		end

		local player = minetest.get_player_by_name(self.player)
		if not player then -- Possible if the player disconnected
			return
		end

		local function hit_failed()
			if not minetest.settings:get_bool("creative_mode") and self.item then
				player:get_inventory():add_item("main", self.item)
			end
			if self.on_hit_fails then
				self:on_hit_fails(pos, player, self.data)
			end
		end

		if not self.last_pos then
			logging("hitted a node during its first call to the step function")
			hit_failed()
			return
		end

		if node and minetest.is_protected(pos, self.player) and not self.allow_protected then -- Forbid hitting nodes in protected areas
			minetest.record_protection_violation(pos, self.player)
			logging("hitted a node into a protected area")
			return
		end

		if self.on_hit then
			local ret, reason = self:on_hit(pos, self.last_pos, node, obj, player, self.data)
			if ret == false then
				if reason then
					logging(": on_hit function failed for reason: "..reason)
				else
					logging(": on_hit function failed")
				end

				hit_failed()
				return
			end
		end

		if self.on_hit_sound then
			minetest.sound_play(self.on_hit_sound, {pos = pos, gain = 0.8})
		end
		if node then
			logging("collided with node "..node.name.." at ("..pos.x..","..pos.y..","..pos.z..")")
		elseif obj then
			if obj:get_luaentity() then
				logging("collided with luaentity "..obj:get_luaentity().name.." at ("..pos.x..","..pos.y..","..pos.z..")")
			elseif obj:is_player() then
				logging("collided with player "..obj:get_player_name().." at ("..pos.x..","..pos.y..","..pos.z..")")
			else
				logging("collided with object at ("..pos.x..","..pos.y..","..pos.z..")")
			end
		end
	end

	-- Collision with a node
	if node.name == "ignore" then
		self.object:remove()
		logging("reached ignore. Removing.")
		return
	elseif node.name ~= "air" then
		if self.target ~= throwing.target_object then -- throwing.target_both, nil, throwing.target_node, or any invalid value
			if hit(pos, node, nil) ~= false then
				self.object:remove()
			end
		else
			self.object:remove()
		end
		return
	end

	-- Collision with an object
	local objs = minetest.get_objects_inside_radius(pos, 1)
	for k, obj in pairs(objs) do
		if obj:get_luaentity() then
			if obj:get_luaentity().name ~= self.name and obj:get_luaentity().name ~= "__builtin:item" then
				if self.target ~= throwing.target_node then -- throwing.target_both, nil, throwing.target_object, or any invalid value
					if hit(pos, nil, obj) ~= false then
						self.object:remove()
					end
				else
					self.object:remove()
				end
			end
		else
			if self.target ~= throwing.target_node then -- throwing.target_both, nil, throwing.target_object, or any invalid value
				if hit(pos, nil, obj) ~= false then
					self.object:remove()
				end
			else
				self.object:remove()
			end
		end
	end


	self.last_pos = pos -- Used by the build arrow
end

function throwing.make_arrow_def(def)
	def.timer = 0
	def.player = ""
	def.on_step = arrow_step
	def.data = {}
	return def
end

--[[
on_hit(pos, last_pos, node, object, hitter)
Either node or object is nil, depending whether the arrow collided with an object (luaentity or player) or with a node.
No log message is needed in this function (a generic log message is automatically emitted), except on error or warning.
Should return false or false, reason on failure.

on_throw(pos, hitter)
Unlike on_hit, it is optional.
]]
function throwing.register_arrow(name, def)
	table.insert(throwing.arrows, name)

	local registration_name = name
	if name:sub(1,9) == "throwing:" then
		registration_name = ":"..name
	end

	if not def.groups then
		def.groups = {}
	end
	if not def.groups.dig_immediate then
		def.groups.dig_immediate = 3
	end
	def.inventory_image = def.tiles[1]
	def.on_place = function(itemstack, placer, pointed_thing)
		if minetest.settings:get_bool("throwing.allow_arrow_placing") and pointed_thing.above then
			local playername = placer:get_player_name()
			if not minetest.is_protected(pointed_thing.above, playername) then
				minetest.log("action", "Player "..playername.." placed arrow "..name.." at ("..pointed_thing.above.x..","..pointed_thing.above.y..","..pointed_thing.above.z..")")
				minetest.set_node(pointed_thing.above, {name = name})
				itemstack:take_item()
				return itemstack
			else
				minetest.log("warning", "Player "..playername.." tried to place arrow "..name.." into a protected area at ("..pointed_thing.above.x..","..pointed_thing.above.y..","..pointed_thing.above.z..")")
				minetest.record_protection_violation(pointed_thing.above, playername)
				return itemstack
			end
		else
			return itemstack
		end
	end
	def.drawtype = "nodebox"
	def.paramtype = "light"
	def.node_box = {
		type = "fixed",
		fixed = {
			-- Shaft
			{-6.5/17, -1.5/17, -1.5/17, 6.5/17, 1.5/17, 1.5/17},
			-- Spitze
			{-4.5/17, 2.5/17, 2.5/17, -3.5/17, -2.5/17, -2.5/17},
			{-8.5/17, 0.5/17, 0.5/17, -6.5/17, -0.5/17, -0.5/17},
			-- Federn
			{6.5/17, 1.5/17, 1.5/17, 7.5/17, 2.5/17, 2.5/17},
			{7.5/17, -2.5/17, 2.5/17, 6.5/17, -1.5/17, 1.5/17},
			{7.5/17, 2.5/17, -2.5/17, 6.5/17, 1.5/17, -1.5/17},
			{6.5/17, -1.5/17, -1.5/17, 7.5/17, -2.5/17, -2.5/17},

			{7.5/17, 2.5/17, 2.5/17, 8.5/17, 3.5/17, 3.5/17},
			{8.5/17, -3.5/17, 3.5/17, 7.5/17, -2.5/17, 2.5/17},
			{8.5/17, 3.5/17, -3.5/17, 7.5/17, 2.5/17, -2.5/17},
			{7.5/17, -2.5/17, -2.5/17, 8.5/17, -3.5/17, -3.5/17},
		}
	}
	minetest.register_node(registration_name, def)

	minetest.register_entity(registration_name.."_entity", throwing.make_arrow_def{
		physical = false,
		visual = "wielditem",
		visual_size = {x = 0.125, y = 0.125},
		textures = {name},
		collisionbox = {0, 0, 0, 0, 0, 0},
		on_hit = def.on_hit,
		on_hit_sound = def.on_hit_sound,
		on_throw_sound = def.on_throw_sound,
		on_throw = def.on_throw,
		allow_protected = def.allow_protected,
		target = def.target,
		on_hit_fails = def.on_hit_fails,
		item = name,
	})

	if def.itemcraft then
		minetest.register_craft({
			output = name.." "..tostring(def.craft_quantity or 1),
			recipe = {
				{def.itemcraft, "default:stick", "default:stick"}
			}
		})
		minetest.register_craft({
			output = name.." "..tostring(def.craft_quantity or 1),
			recipe = {
				{ "default:stick", "default:stick", def.itemcraft}
			}
		})
	end
end


---------- Bows -----------
function throwing.register_bow(name, def)
	if not def.allow_shot then
		def.allow_shot = function(player, itemstack, index)
			if index >= player:get_inventory():get_size("main") and not def.throw_itself then
				return false
			end
			return throwing.is_arrow(itemstack)
		end
	end
	if not def.inventory_image then
		def.inventory_image = def.texture
	end
	def.on_use = function(itemstack, user, pointed_thing)
		-- Cooldown
		local meta = itemstack:get_meta()
		local cooldown = def.cooldown or tonumber(minetest.settings:get("throwing.bow_cooldown")) or 0.2

		if cooldown > 0 and meta:get_int("cooldown") > os.time()
				or meta:get_int("delay") > os.time() then
			return
		end

		local bow_index = user:get_wield_index()
		local arrow_index = (def.throw_itself and bow_index) or bow_index+1
		local res, new_stack = def.allow_shot(user, user:get_inventory():get_stack("main", arrow_index), arrow_index, false)
		if not res then
			return (def.throw_itself and new_stack) or itemstack
		end

		-- Sound
		if def.sound then
			minetest.sound_play(def.sound, {to_player=user:get_player_name()})
		end

		meta:set_int("delay", os.time() + (def.delay or 0))
		minetest.after(def.delay or 0, function()
			-- Re-check that the arrow can be thrown. Overwrite the new_stack
			local old_new_stack = new_stack
			res, new_stack = def.allow_shot(user, user:get_inventory():get_stack("main", arrow_index), arrow_index, true)
			if not new_stack then
				new_stack = old_new_stack
			end
			if not res then
				return
			end

			-- Shoot arrow
			if shoot_arrow(itemstack, user, bow_index, def.throw_itself, new_stack) then
				if not minetest.settings:get_bool("creative_mode") then
					itemstack:add_wear(65535 / (def.uses or 50))
				end
			end


			if def.throw_itself then
				-- This is a bug. If we return ItemStack(nil), the player punches the entity,
				-- and if the entity if a __builtin:item, it gets back to his inventory.
				minetest.after(0.1, function()
					user:get_inventory():remove_item("main", itemstack)
				end)
			elseif cooldown > 0 then
				meta:set_int("cooldown", os.time() + cooldown)
			end
			user:get_inventory():set_stack("main", bow_index, itemstack)
		end)
		return itemstack
	end
	minetest.register_tool(name, def)

	if def.itemcraft then
		-- Check for an override name
		-- because an ``output = ":name"'' can't exist in a recipe
		local outpout_name = name
		if name:sub(1,1) == ":" then
			output_name = name:sub(2)
		end
		minetest.register_craft({
			output = output_name,
			recipe = {
				{"farming:cotton", def.itemcraft, ""},
				{"farming:cotton", "", def.itemcraft},
				{"farming:cotton", def.itemcraft, ""},
			}
		})
	end
end