-- A pixie is like a sprite, but better

import "CoreLibs/object"
import "CoreLibs/graphics"
import "CoreLibs/sprites"

local gfx <const> = playdate.graphics

class("Pixie").extends(gfx.sprite)

-- Crong pixies are simple rectangles, so they take an initial position, width, height, and color
-- They are also collidable
function Pixie:init(width, height, color, x, y)
   x = x or 0
   y = y or 0

   Pixie.super.init(self, gfx.image.new(width, height, color))
   self:setCollideRect(0, 0, self:getSize())
   self:moveTo(x, y)
   return self
end

function Pixie:moveTo(x, y)
   Pixie.super.moveTo(self, x, y)
   self:_normalizePosition()
end

function Pixie:moveBy(x, y)
   Pixie.super.moveBy(self, x, y)
   self:_normalizePosition()
end

function Pixie:_normalizePosition()
   local limitTop = self.height / 2
   local limitBottom = 240 - limitTop
   local limitLeft = self.width / 2
   local limitRight = 400 - limitLeft

   local changedX = 0
   local changedY = 0
   local newX = self.x
   local newY = self.y
   
   if self.y < limitTop then
      newY = limitTop
      changedY = 1
   end

   if self.y > limitBottom then
      newY = limitBottom
      changedY = -1
   end

   if self.x < limitLeft then
      newX = limitLeft
      changedX = 1
   end

   if self.x > limitRight then
      newX = limitRight
      changedX = -1
   end

   if changedX ~= 0 or changedY ~= 0 then
      -- call super to avoid the odd possibility that we recurse back into
      -- this function
      Pixie.super.moveTo(self, newX, newY)
   end

   return {changedX, changedY}
end