local math, vector, minetest, mcl_mobs = math, vector, minetest, mcl_mobs
local mob_class = mcl_mobs.mob_class

local damage_enabled = minetest.settings:get_bool("enable_damage")
local mobs_griefing = minetest.settings:get_bool("mobs_griefing") ~= false

local show_health = false
-- pathfinding settings
local stuck_timeout = 3 -- how long before mob gets stuck in place and starts searching
local stuck_path_timeout = 10 -- how long will mob follow path before giving up

-- check if daytime and also if mob is docile during daylight hours
function mob_class:day_docile()
	if self.docile_by_day == false then
		return false
	elseif self.docile_by_day == true
	and self.time_of_day > 0.2
	and self.time_of_day < 0.8 then
		return true
	end
end

-- attack player/mob
function mob_class:do_attack(player)

	if self.state == "attack" or self.state == "die" then
		return
	end

	self.attack = player
	self.state = "attack"

	-- TODO: Implement war_cry sound without being annoying
	--if random(0, 100) < 90 then
		--self:mob_sound("war_cry", true)
	--end
end

-- blast damage to entities nearby
local function entity_physics(pos,radius)

	radius = radius * 2

	local objs = minetest.get_objects_inside_radius(pos, radius)
	local obj_pos, dist

	for n = 1, #objs do

		obj_pos = objs[n]:get_pos()

		dist = vector.distance(pos, obj_pos)
		if dist < 1 then dist = 1 end

		local damage = math.floor((4 / dist) * radius)
		local ent = objs[n]:get_luaentity()

		-- punches work on entities AND players
		objs[n]:punch(objs[n], 1.0, {
			full_punch_interval = 1.0,
			damage_groups = {fleshy = damage},
		}, pos)
	end
end

function mob_class:entity_physics(self,pos,radius) return entity_physics(pos,radius) end

local los_switcher = false
local height_switcher = false

-- path finding and smart mob routine by rnd, line_of_sight and other edits by Elkien3
function mob_class:smart_mobs(s, p, dist, dtime)

	local s1 = self.path.lastpos

	local target_pos = self.attack:get_pos()

	-- is it becoming stuck?
	if math.abs(s1.x - s.x) + math.abs(s1.z - s.z) < .5 then
		self.path.stuck_timer = self.path.stuck_timer + dtime
	else
		self.path.stuck_timer = 0
	end

	self.path.lastpos = {x = s.x, y = s.y, z = s.z}

	local use_pathfind = false
	local has_lineofsight = minetest.line_of_sight(
		{x = s.x, y = (s.y) + .5, z = s.z},
		{x = target_pos.x, y = (target_pos.y) + 1.5, z = target_pos.z}, .2)

	-- im stuck, search for path
	if not has_lineofsight then

		if los_switcher == true then
			use_pathfind = true
			los_switcher = false
		end -- cannot see target!
	else
		if los_switcher == false then

			los_switcher = true
			use_pathfind = false

			minetest.after(1, function(self)
				if not self.object:get_luaentity() then
					return
				end
				if has_lineofsight then self.path.following = false end
			end, self)
		end -- can see target!
	end

	if (self.path.stuck_timer > stuck_timeout and not self.path.following) then

		use_pathfind = true
		self.path.stuck_timer = 0

		minetest.after(1, function(self)
			if not self.object:get_luaentity() then
				return
			end
			if has_lineofsight then self.path.following = false end
		end, self)
	end

	if (self.path.stuck_timer > stuck_path_timeout and self.path.following) then

		use_pathfind = true
		self.path.stuck_timer = 0

		minetest.after(1, function(self)
			if not self.object:get_luaentity() then
				return
			end
			if has_lineofsight then self.path.following = false end
		end, self)
	end

	if math.abs(vector.subtract(s,target_pos).y) > self.stepheight then

		if height_switcher then
			use_pathfind = true
			height_switcher = false
		end
	else
		if not height_switcher then
			use_pathfind = false
			height_switcher = true
		end
	end

	if use_pathfind then
		-- lets try find a path, first take care of positions
		-- since pathfinder is very sensitive
		local sheight = self.collisionbox[5] - self.collisionbox[2]

		-- round position to center of node to avoid stuck in walls
		-- also adjust height for player models!
		s.x = math.floor(s.x + 0.5)
		s.z = math.floor(s.z + 0.5)

		local ssight, sground = minetest.line_of_sight(s, {
			x = s.x, y = s.y - 4, z = s.z}, 1)

		-- determine node above ground
		if not ssight then
			s.y = sground.y + 1
		end

		local p1 = self.attack:get_pos()

		p1.x = math.floor(p1.x + 0.5)
		p1.y = math.floor(p1.y + 0.5)
		p1.z = math.floor(p1.z + 0.5)

		local dropheight = 12
		if self.fear_height ~= 0 then dropheight = self.fear_height end
		local jumpheight = 0
		if self.jump and self.jump_height >= 4 then
			jumpheight = math.min(math.ceil(self.jump_height / 4), 4)
		elseif self.stepheight > 0.5 then
			jumpheight = 1
		end
		self.path.way = minetest.find_path(s, p1, 16, jumpheight, dropheight, "A*_noprefetch")

		self.state = ""
		do_attack(self, self.attack)

		-- no path found, try something else
		if not self.path.way then

			self.path.following = false

			 -- lets make way by digging/building if not accessible
			if self.pathfinding == 2 and mobs_griefing then

				-- is player higher than mob?
				if s.y < p1.y then

					-- build upwards
					if not minetest.is_protected(s, "") then

						local ndef1 = minetest.registered_nodes[self.standing_in]

						if ndef1 and (ndef1.buildable_to or ndef1.groups.liquid) then

								minetest.set_node(s, {name = mcl_mobs.fallback_node})
						end
					end

					local sheight = math.ceil(self.collisionbox[5]) + 1

					-- assume mob is 2 blocks high so it digs above its head
					s.y = s.y + sheight

					-- remove one block above to make room to jump
					if not minetest.is_protected(s, "") then

						local node1 = node_ok(s, "air").name
						local ndef1 = minetest.registered_nodes[node1]

						if node1 ~= "air"
						and node1 ~= "ignore"
						and ndef1
						and not ndef1.groups.level
						and not ndef1.groups.unbreakable
						and not ndef1.groups.liquid then

							minetest.set_node(s, {name = "air"})
							minetest.add_item(s, ItemStack(node1))

						end
					end

					s.y = s.y - sheight
					self.object:set_pos({x = s.x, y = s.y + 2, z = s.z})

				else -- dig 2 blocks to make door toward player direction

					local yaw1 = self.object:get_yaw() + math.pi / 2
					local p1 = {
						x = s.x + math.cos(yaw1),
						y = s.y,
						z = s.z + math.sin(yaw1)
					}

					if not minetest.is_protected(p1, "") then

						local node1 = node_ok(p1, "air").name
						local ndef1 = minetest.registered_nodes[node1]

						if node1 ~= "air"
							and node1 ~= "ignore"
							and ndef1
							and not ndef1.groups.level
							and not ndef1.groups.unbreakable
							and not ndef1.groups.liquid then

							minetest.add_item(p1, ItemStack(node1))
							minetest.set_node(p1, {name = "air"})
						end

						p1.y = p1.y + 1
						node1 = node_ok(p1, "air").name
						ndef1 = minetest.registered_nodes[node1]

						if node1 ~= "air"
						and node1 ~= "ignore"
						and ndef1
						and not ndef1.groups.level
						and not ndef1.groups.unbreakable
						and not ndef1.groups.liquid then

							minetest.add_item(p1, ItemStack(node1))
							minetest.set_node(p1, {name = "air"})
						end

					end
				end
			end

			-- will try again in 2 seconds
			self.path.stuck_timer = stuck_timeout - 2
		elseif s.y < p1.y and (not self.fly) then
			do_jump(self) --add jump to pathfinding
			self.path.following = true
			-- Yay, I found path!
			-- TODO: Implement war_cry sound without being annoying
			--self:mob_sound("war_cry", true)
		else
			self:set_velocity(self.walk_velocity)

			-- follow path now that it has it
			self.path.following = true
		end
	end
end


-- specific attacks
local specific_attack = function(list, what)

	-- no list so attack default (player, animals etc.)
	if list == nil then
		return true
	end

	-- found entity on list to attack?
	for no = 1, #list do

		if list[no] == what then
			return true
		end
	end

	return false
end

-- find someone to attack
function mob_class:monster_attack()
	if not damage_enabled
	or self.passive ~= false
	or self.state == "attack"
	or self:day_docile() then
		return
	end

	local s = self.object:get_pos()
	local p, sp, dist
	local player, obj, min_player
	local type, name = "", ""
	local min_dist = self.view_range + 1
	local objs = minetest.get_objects_inside_radius(s, self.view_range)
	local blacklist_attack = {}

	for n = 1, #objs do
		if not objs[n]:is_player() then
			obj = objs[n]:get_luaentity()

			if obj then
				player = obj.object
				name = obj.name or ""
			end
			if obj and obj.type == self.type and obj.passive == false and obj.state == "attack" and obj.attack then
				table.insert(blacklist_attack, obj.attack)
			end
		end
	end

	for n = 1, #objs do


		if objs[n]:is_player() then
			if mcl_mobs.invis[ objs[n]:get_player_name() ] or (not self:object_in_range(objs[n])) then
				type = ""
			elseif (self.type == "monster" or self._aggro) then
				player = objs[n]
				type = "player"
				name = "player"
			end
		else
			obj = objs[n]:get_luaentity()

			if obj then
				player = obj.object
				type = obj.type
				name = obj.name or ""
			end

		end

		-- find specific mob to attack, failing that attack player/npc/animal
		if specific_attack(self.specific_attack, name)
		and (type == "player" or ( type == "npc" and self.attack_npcs )
			or (type == "animal" and self.attack_animals == true)) then

			p = player:get_pos()
			sp = s

			dist = vector.distance(p, s)

			-- aim higher to make looking up hills more realistic
			p.y = p.y + 1
			sp.y = sp.y + 1

			local attacked_p = false
			for c=1, #blacklist_attack do
				if blacklist_attack[c] == player then
					attacked_p = true
				end
			end
			-- choose closest player to attack
			if dist < min_dist
			and not attacked_p
			and self:line_of_sight( sp, p, 2) == true then
				min_dist = dist
				min_player = player
			end
		end
	end
	if not min_player and #blacklist_attack > 0 then
		min_player=blacklist_attack[math.random(#blacklist_attack)]
	end
	-- attack player
	if min_player then
		self:do_attack(min_player)
	end
end


-- npc, find closest monster to attack
function mob_class:npc_attack()

	if self.type ~= "npc"
	or not self.attacks_monsters
	or self.state == "attack" then
		return
	end

	local p, sp, obj, min_player
	local s = self.object:get_pos()
	local min_dist = self.view_range + 1
	local objs = minetest.get_objects_inside_radius(s, self.view_range)

	for n = 1, #objs do

		obj = objs[n]:get_luaentity()

		if obj and obj.type == "monster" then

			p = obj.object:get_pos()
			sp = s

			local dist = vector.distance(p, s)

			-- aim higher to make looking up hills more realistic
			p.y = p.y + 1
			sp.y = sp.y + 1

			if dist < min_dist
			and self:line_of_sight( sp, p, 2) == true then
				min_dist = dist
				min_player = obj.object
			end
		end
	end

	if min_player then
		self:do_attack(min_player)
	end
end



-- dogshoot attack switch and counter function
function mob_class:dogswitch(dtime)

	-- switch mode not activated
	if not self.dogshoot_switch
	or not dtime then
		return 0
	end

	self.dogshoot_count = self.dogshoot_count + dtime

	if (self.dogshoot_switch == 1
	and self.dogshoot_count > self.dogshoot_count_max)
	or (self.dogshoot_switch == 2
	and self.dogshoot_count > self.dogshoot_count2_max) then

		self.dogshoot_count = 0

		if self.dogshoot_switch == 1 then
			self.dogshoot_switch = 2
		else
			self.dogshoot_switch = 1
		end
	end

	return self.dogshoot_switch
end

-- no damage to nodes explosion
function mob_class:safe_boom(pos, strength)
	minetest.sound_play(self.sounds and self.sounds.explode or "tnt_explode", {
		pos = pos,
		gain = 1.0,
		max_hear_distance = self.sounds and self.sounds.distance or 32
	}, true)
	local radius = strength
	entity_physics(pos, radius)
	mcl_mobs.effect(pos, 32, "mcl_particles_smoke.png", radius * 3, radius * 5, radius, 1, 0)
end


-- make explosion with protection and tnt mod check
function mob_class:boom(pos, strength, fire)
	if mobs_griefing and not minetest.is_protected(pos, "") then
		mcl_explosions.explode(pos, strength, { drop_chance = 1.0, fire = fire }, self.object)
	else
		mcl_mobs.mob_class.safe_boom(self, pos, strength) --need to call it this way bc self is the "arrow" object here
	end

	-- delete the object after it punched the player to avoid nil entities in e.g. mcl_shields!!
	self.object:remove()
end

-- deal damage and effects when mob punched
function mob_class:on_punch(hitter, tflp, tool_capabilities, dir)

	-- custom punch function
	if self.do_punch then

		-- when false skip going any further
		if self.do_punch(self, hitter, tflp, tool_capabilities, dir) == false then
			return
		end
	end

	-- error checking when mod profiling is enabled
	if not tool_capabilities then
		minetest.log("warning", "[mobs] Mod profiling enabled, damage not enabled")
		return
	end

	local is_player = hitter:is_player()

	if is_player then
		-- is mob protected?
		if self.protected and minetest.is_protected(self.object:get_pos(), hitter:get_player_name()) then
			return
		end

		if minetest.is_creative_enabled(hitter:get_player_name()) then
			self.health = 0
		end

		-- set/update 'drop xp' timestamp if hitted by player
		self.xp_timestamp = minetest.get_us_time()
	end


	-- punch interval
	local weapon = hitter:get_wielded_item()
	local punch_interval = 1.4

	-- exhaust attacker
	if is_player then
		mcl_hunger.exhaust(hitter:get_player_name(), mcl_hunger.EXHAUST_ATTACK)
	end

	-- calculate mob damage
	local damage = 0
	local armor = self.object:get_armor_groups() or {}
	local tmp

	-- quick error check incase it ends up 0 (serialize.h check test)
	if tflp == 0 then
		tflp = 0.2
	end


	for group,_ in pairs( (tool_capabilities.damage_groups or {}) ) do

		tmp = tflp / (tool_capabilities.full_punch_interval or 1.4)

		if tmp < 0 then
			tmp = 0.0
		elseif tmp > 1 then
			tmp = 1.0
		end

		damage = damage + (tool_capabilities.damage_groups[group] or 0)
			* tmp * ((armor[group] or 0) / 100.0)
	end

	if weapon then
		local fire_aspect_level = mcl_enchanting.get_enchantment(weapon, "fire_aspect")
		if fire_aspect_level > 0 then
			mcl_burning.set_on_fire(self.object, fire_aspect_level * 4)
		end
	end

	-- check for tool immunity or special damage
	for n = 1, #self.immune_to do

		if self.immune_to[n][1] == weapon:get_name() then

			damage = self.immune_to[n][2] or 0
			break
		end
	end

	-- healing
	if damage <= -1 then
		self.health = self.health - math.floor(damage)
		return
	end

	if tool_capabilities then
		punch_interval = tool_capabilities.full_punch_interval or 1.4
	end

	-- add weapon wear manually
	-- Required because we have custom health handling ("health" property)
	if minetest.is_creative_enabled("") ~= true
	and tool_capabilities then
		if tool_capabilities.punch_attack_uses then
			-- Without this delay, the wear does not work. Quite hacky ...
			minetest.after(0, function(name)
				local player = minetest.get_player_by_name(name)
				if not player then return end
				local weapon = hitter:get_wielded_item(player)
				local def = weapon:get_definition()
				if def.tool_capabilities and def.tool_capabilities.punch_attack_uses then
					local wear = math.floor(65535/tool_capabilities.punch_attack_uses)
					weapon:add_wear(wear)
					hitter:set_wielded_item(weapon)
				end
			end, hitter:get_player_name())
		end
	end

	local die = false


	if damage >= 0 then
		-- only play hit sound and show blood effects if damage is 1 or over; lower to 0.1 to ensure armor works appropriately.
		if damage >= 0.1 then
			-- weapon sounds
			if weapon:get_definition().sounds ~= nil then

				local s = math.random(0, #weapon:get_definition().sounds)

				minetest.sound_play(weapon:get_definition().sounds[s], {
					object = self.object, --hitter,
					max_hear_distance = 8
				}, true)
			else
				minetest.sound_play("default_punch", {
					object = self.object,
					max_hear_distance = 5
				}, true)
			end

			self:damage_effect(damage)

			-- do damage
			self.health = self.health - damage

			-- skip future functions if dead, except alerting others
			if self:check_for_death( "hit", {type = "punch", puncher = hitter}) then
				die = true
			end
		end
		-- knock back effect (only on full punch)
		if self.knock_back
		and tflp >= punch_interval then
			-- direction error check
			dir = dir or {x = 0, y = 0, z = 0}

			local v = self.object:get_velocity()
			if not v then return end
			local r = 1.4 - math.min(punch_interval, 1.4)
			local kb = r * (math.abs(v.x)+math.abs(v.z))
			local up = 2

			if die==true then
				kb=kb*2
			end

			-- if already in air then dont go up anymore when hit
			if math.abs(v.y) > 0.1
			or self.fly then
				up = 0
			end


			-- check if tool already has specific knockback value
			if tool_capabilities.damage_groups["knockback"] then
				kb = tool_capabilities.damage_groups["knockback"]
			else
				kb = kb * 1.5
			end


			local luaentity
			if hitter then
				luaentity = hitter:get_luaentity()
			end
			if hitter and is_player then
				local wielditem = hitter:get_wielded_item()
				kb = kb + 3 * mcl_enchanting.get_enchantment(wielditem, "knockback")
			elseif luaentity and luaentity._knockback then
				kb = kb + luaentity._knockback
			end
			self._kb_turn = true
			self._turn_to=self.object:get_yaw()-1.57
			self.frame_speed_multiplier=2.3
			if self.animation.run_end then
				self:set_animation( "run")
			elseif self.animation.walk_end then
				self:set_animation( "walk")
			end
			minetest.after(0.2, function()
				if self and self.object then
					self.frame_speed_multiplier=1
					self._kb_turn = false
				end
			end)
			self.object:add_velocity({
				x = dir.x * kb,
				y = up*2,
				z = dir.z * kb
			})

			self.pause_timer = 0.25
		end
	end -- END if damage

	-- if skittish then run away
	if hitter and is_player and hitter:get_pos() and not die and self.runaway == true and self.state ~= "flop" then

		local yaw = self:set_yaw( minetest.dir_to_yaw(vector.direction(hitter:get_pos(), self.object:get_pos())))
		minetest.after(0.2,function()
			if self and self.object and self.object:get_pos() and hitter and is_player and hitter:get_pos() then
				yaw = self:set_yaw( minetest.dir_to_yaw(vector.direction(hitter:get_pos(), self.object:get_pos())))
				self:set_velocity( self.run_velocity)
			end
		end)
		self.state = "runaway"
		self.runaway_timer = 0
		self.following = nil
	end

	local name = hitter:get_player_name() or ""

	-- attack puncher and call other mobs for help
	if self.passive == false
	and self.state ~= "flop"
	and (self.child == false or self.type == "monster")
	and hitter:get_player_name() ~= self.owner
	and not mcl_mobs.invis[ name ] then
		if not die then
			-- attack whoever punched mob
			self.state = ""
			self:do_attack(hitter)
			self._aggro= true
		end

		-- alert others to the attack
		local objs = minetest.get_objects_inside_radius(hitter:get_pos(), self.view_range)
		local obj = nil

		for n = 1, #objs do

			obj = objs[n]:get_luaentity()

			if obj then
				-- only alert members of same mob or friends
				if obj.group_attack
				and obj.state ~= "attack"
				and obj.owner ~= name then
					if obj.name == self.name then
						obj:do_attack(hitter)
					elseif type(obj.group_attack) == "table" then
						for i=1, #obj.group_attack do
							if obj.name == obj.group_attack[i] then
								obj._aggro = true
								obj:do_attack(hitter)
								break
							end
						end
					end
				end

				-- have owned mobs attack player threat
				if obj.owner == name and obj.owner_loyal then
					obj:do_attack(self.object)
				end
			end
		end
	end
end

function mob_class:check_aggro(dtime)
	if not self._aggro or not self.attack then return end
	if not self._check_aggro_timer or self._check_aggro_timer > 5 then
		self._check_aggro_timer = 0
		if not self.attack:get_pos() or vector.distance(self.attack:get_pos(),self.object:get_pos()) > 128 then
			self._aggro = nil
			self.attack = nil
			self.state = "stand"
		end
	end
	self._check_aggro_timer = self._check_aggro_timer + dtime
end