Entity = {}

function Entity:New(x,y)
	o = {}
	o.pos = {x = x, y = y}
	o.vel = {x = 0, y = 0}
  o.target = {x = 0, y = 0}
  o.hitbox = 0
	o.angle = 0
	o.direction = 0
  o.show_health = false
	o.id = {}
	setmetatable(o, self)
	self.__index = self
	return o
end

function Entity:Damage(damage)
	self.health = self.health - damage
	if self.health <= 0 then
		self:Kill()
	end
end

function Entity:DrawHealth()
	local width = 400
	local height = 10
		love.graphics.setColor(1,1,1)
  love.graphics.rectangle(
		"fill",
		self.pos.x - width/2,
		self.pos.y - height * self.draw_scale,
		width,
		height
	)
	love.graphics.setColor(1,0,0)
	love.graphics.rectangle(
		"fill",
		self.pos.x - width/2+1,
		self.pos.y - height * self.draw_scale+1,
		self.health/self.max_health*(width-2),
		height-2
	)
		love.graphics.setColor(1,1,1)

end

function Entity:AddList( target)
	if List[target] == nil then List[target] = {} end
	table.insert(List[target],self)
 	self.id[target] = #List[target]
end

function Entity:RemoveList(target)
	if self.id[target] ~= nil then
		for _, e in pairs(List[target]) do
			if e.id[target] > self.id[target] then
				e.id[target] = e.id[target] - 1
			end
		end
		table.remove(List[target],self.id[target])
	end
end

function Entity:DistanceWith(obj, distance)
	if math.sqrt((obj.pos.x-self.pos.x)^2 + (obj.pos.y-self.pos.y)^2) < distance then
		return true
	else
		return false
	end
end

function Entity:Kill()
	for target, _ in pairs(self.id) do
		self:RemoveList(target)
	end

	self = nil
end

function Entity:AngleTowards(x,y)
  target_x = x - self.pos.x
  target_y = y - self.pos.y

  self.angle = GetAngleFromVector(target_x,target_y)
end


function Entity:MoveTowards(x,y,speed)
  target_x = x - self.pos.x
  target_y = y - self.pos.y

	local angle = GetAngleFromVector(target_x,target_y)

	if speed ~= 0 then
		if target_x ~= 0 then
	  	self.vel.x = speed * math.cos(angle)
		else
			self.vel.x = 0
		end
		if target_y ~= 0 then
			self.vel.y = speed * math.sin(angle)
		else
			self.vel.y = 0
		end
	end
end

require "scripts/entities/player"
require "scripts/entities/enemy/fang"
require "scripts/entities/enemy/shooter"
require "scripts/entities/bullet"