local Object = require "classic"
local Slider = Object:extend()

active = false

function Slider:new(x, y, w, h, limit)
    self.x = x or 0
    self.y = y or 0
    self.w = w or 0
    self.h = h or 0
    self.knobw = 8
    self.knobh = 16
    self.knobx = self.x
    self.knoby = self.y
    self.active = false
    self.level = 0
    self.limit = 255
end

function round(n)
  return math.floor(n + 0.5)
end

function Slider:update(dt)
    mousex, mousey = love.mouse.getPosition()
    self.level = round(((self.knobx-self.x)/self.w)*255)
    
    if self.level < 0 then
        self.knobx = self.x
        self.level = 0
    elseif self.level > 255 then
        self.knobx = self.x+self.w
        self.level = 255
    end
    
    if love.mouse.isDown(1)
    and mousex >= self.x
    and mousex <= self.x+self.w
    and mousey >= self.y
    and mousey <= self.y+self.h
    and not active
    and self.active == false then
        self.active = true
        active = true
    elseif love.mouse.isDown(1) == false then
        self.active = false
        active = false
    end
    if self.active then
        self.knobx = round(
            (math.min (math.max(self.x, mousex), self.x+self.w)
        )/(self.w/255)
        )*(self.w/255)
    end
end

function Slider:draw()
    love.graphics.setColor(200/255, 200/255, 200/255)
    love.graphics.rectangle("line", self.x, self.y, self.w, self.h)
    love.graphics.setColor(237/255, 86/255, 83/255)
    love.graphics.rectangle("fill", self.knobx-(self.knobw/2), self.knoby-(self.knobh/3), self.knobw, self.knobh)
    love.graphics.setColor(1, 1, 1)
    love.graphics.print(self.level, self.x-32, self.y-self.h/2)
end

return Slider