pets = {}
pets.players_pets = {}
pets.pet_file = minetest.get_worldpath() .. "/pets"

local function get_velocity(v, yaw, y)
	local x = -math.sin(yaw) * v
	local z =  math.cos(yaw) * v
	return {x = x, y = y, z = z}
end

function pets.register_pet(name, def)
	minetest.register_entity(name, {
		hp_max = def.hp_max,
		physical = true,
		collisionbox = def.collisionbox,
	 	visual = "mesh",
	 	visual_size = {x=1, y=1},
		mesh = def.mesh,
		textures = def.textures,
		spritediv = {x=1, y=1},
		initial_sprite_basepos = {x=0, y=0},	
		is_visible = true,
		makes_footstep_sound = false,
		automatic_rotate = true,
		speed = 0,
		pl = nil,
		is_pet = false,
		anim = "stand",

		on_rightclick = function(self, clicker)
			if not clicker or not clicker:is_player() then
				return
			end
			if pets.players_pets[clicker:get_player_name()] then
				cmsg.push_message_player(clicker, "[pet] You already have a pet!")
			else
				if clicker:get_wielded_item():get_name() == (def.food or "farming:wheat_seeds") then
					local wielded_item = clicker:get_wielded_item()
					wielded_item:take_item()
					clicker:set_wielded_item(wielded_item)
					
					pets.players_pets[clicker:get_player_name()] = name
					cmsg.push_message_player(clicker, "[pet] + ".. def.description)
					self.pl = clicker
					pets.players_pets[clicker:get_player_name()] = name
					pets.save_pets()
				end
			end
		end,

		on_step = function(self, dtime)
			if self.pl ~= nil then
				if self.pl:getpos() then
					self.object:set_armor_groups({fleshy = 0, friendly = 100}) 
					local t = self.pl:getpos()
					t.x = t.x + 1.5
					t.z = t.z + 1.5
					if vector.distance(self.object:getpos(), t) > 2 then 
						local vec = vector.direction(self.object:getpos(), t)
						--vec.y = vec.y * 10
						if self.object:getpos().y < t.y+0.5 then
							vec.y= vec.y + 2
						else
							vec.y= -3
						end
						self.object:setvelocity(vector.multiply(vec, 3))
						local yaw = math.atan(vec.z/vec.x)+math.pi/2
						yaw = yaw+(math.pi/2)
						if t.x > t.z then
							yaw = yaw+math.pi
						end
						self.object:setyaw(yaw)
						if def.animations then
							if self.anim ~= "walk" then
								self.anim = "walk"
								self.object:set_animation({x=def.animations.walk.x,y=def.animations.walk.y}, 30, 0) 
							end
						end
					else
						self.object:setvelocity({x=0, y=0, z=0})
						if def.animations then
							if self.anim ~= "stand" then
								self.anim = "stand"
								self.object:set_animation({x=def.animations.sit.x,y=def.animations.sit.y}, 30, 0) 
							end
						end
					end
					if vector.distance(self.object:getpos(), self.pl:getpos()) > 15 then 
						local vec = self.pl:getpos()
						vec.x = vec.x + math.random(-3, 3)
						vec.z = vec.z + math.random(-3, 3)
						vec.y = vec.y + 3
						self.object:setpos(vec)
					end
				end
			else
				if self.is_pet then
					print("[info] remove pet")
					self.object:remove()
					return
				end
				if math.random(0, 50) == 15 then 
					local vec = {x=math.random(-3, 3), y=-4, z=math.random(-3, 3)}
					self.object:setvelocity(vec)
					local yaw = math.atan(vec.z/vec.x)+math.pi/2
					yaw = yaw+(math.pi/2)
					if vec.x + self.object:getpos().x > self.object:getpos().x then
						yaw = yaw+math.pi
					end
					self.object:setyaw(yaw)
					if def.animations then
						self.object:set_animation({x=def.animations.walk.x,y=def.animations.walk.y}, 30, 0) 
					end
				end
			end
		end,
	})

	minetest.register_craftitem(name, {
		description = def.description,
		inventory_image = "pets_"..def.description.."_spawn.png",

		on_place = function(itemstack, placer, pointed_thing)
			if pointed_thing.type ~= "node" then
				return
			end
			minetest.add_entity(pointed_thing.above, name)
			if not minetest.setting_getbool("creative_mode") then
				itemstack:take_item()
			end
			return itemstack
		end,
	})
end 

-- load save

function pets.load_pets()
	local input = io.open(pets.pet_file, "r")
	if input then
		local str = input:read()
		if str then
			for k, v1, v2 in str.gmatch(str,"(%w+)=(%w+):(%w+)") do
    				pets.players_pets[k] = v1 .. ":" .. v2
			end
		end
		io.close(input)
	end
end

function pets.save_pets()
	if pets.players_pets then
		local output = io.open(pets.pet_file, "w")
		local str = ""
		for k, v in pairs(pets.players_pets) do 
			str = str .. k .. "=" .. v .. ","
		end
		str = str:sub(1, #str - 1)
		output:write(str)
		io.close(output)
	end
end

minetest.register_on_joinplayer(function(player)
	if pets.players_pets[player:get_player_name()] then
		print("[pets] add entity " .. pets.players_pets[player:get_player_name()])
		minetest.after(3, function(player)
			if not player then
				return
			end
			local vec = player:getpos()
			vec.x = vec.x + math.random(-3, 3)
			vec.z = vec.z + math.random(-3, 3)
			vec.y = vec.y + 3
			local plpet = minetest.add_entity(vec, pets.players_pets[player:get_player_name()])
			plpet:get_luaentity().pl = player
			plpet:get_luaentity().is_pet = true
		end , player)
	end
end)

pets.register_pet("pets:pig", {
	description  = "pig",
	hp_max = 30,
	collisionbox = {-0.3,-0.5,-0.3, 0.3,0.1,0.3},
	mesh = "pets_pig.x",
	textures = {"pets_pig.png",},
})

pets.register_pet("pets:sheep", {
	description  = "sheep",
	hp_max = 25,
	collisionbox = {-0.5,-0.5,-0.5, 0.5,0.5,0.5},
	mesh = "pets_sheep.x",
	textures = {"pets_sheep.png",},
})

pets.load_pets()