------------------------------------------------------------------------------
-- Imports
------------------------------------------------------------------------------

local love = require 'love'
local make_class = require 'src.classes'
local GameState = require 'src.gstate'
local Fader = require 'src.fader'


------------------------------------------------------------------------------
-- Class definitions
------------------------------------------------------------------------------

local Intro = make_class(GameState)


------------------------------------------------------------------------------
-- Class methods
------------------------------------------------------------------------------

function Intro:_init(name, index)
    GameState._init(self, name, index)
    self.skip = false
    self.fade = Fader()
    self.stage = 0
    self.timer = 0
end


function Intro:load()
    self.splash = love.graphics.newImage('imgs/splash.png')
    self.author = love.graphics.newImage('imgs/wally.png')
    self.title = love.graphics.newImage('imgs/title.png')
    self.splash_snd = love.audio.newSource('snd/jachiev.wav')
    self.author_snd = love.audio.newSource('snd/alang.wav')
    self.title_snd = love.audio.newSource('snd/ablhole.wav')
    self.valid = true

    self.splash_snd:play()
end


function Intro:update(dt)
    local total_time

    if self.stage == 0 then
        total_time = 4.5
    elseif self.stage == 1 then
        total_time = 3.0
    else
        total_time = 8.0
    end

    if self.fade.done then
        self.timer = self.timer + dt
    end

    if self.timer >= total_time then
        self.fade:fade_out(
            function ()
                self.stage = self.stage + 1

                if self.stage == 1 then
                    self.author_snd:play()
                elseif self.stage == 2 then
                    self.title_snd:play()
                end

                self.fade:fade_in()
            end
        )
        self.timer = 0.0
    end

    self.fade:update(dt)

    if not self.skip and self.stage < 3 then return self.index else return 2 end
end


function Intro:draw()
    if self.valid then
        if self.stage == 0 then love.graphics.draw(self.splash, 0, 0)
        elseif self.stage == 1 then love.graphics.draw(self.author, 0, 0)
        elseif self.stage == 2 then love.graphics.draw(self.title, 0, 0) end
    end

    self.fade:draw()
end


function Intro:unload()
    self.splash = nil
    self.author = nil
    self.title = nil
    self.splash_snd = nil
    self.author_snd = nil
    self.title_snd = nil
    self.valid = false
end


function Intro:keypressed(_)
    self.skip = true
end


------------------------------------------------------------------------------
-- Module return
------------------------------------------------------------------------------

return Intro