--
-- EXF: Example Framework
--
-- This should make examples easier and more enjoyable to use.
-- All examples in one application! Yaay!
--
-- Updated by Dresenpai

require "lib/postshader"
local LightWorld = require "lib"

exf = {}
exf.current = nil

exf.available = {}

function love.load()
  exf.list = List:new()
  exf.smallfont = love.graphics.newFont(love._vera_ttf,12)
  exf.bigfont = love.graphics.newFont(love._vera_ttf, 24)
  exf.list.font = exf.smallfont

  exf.bigball = love.graphics.newImage("examples/gfx/love-big-ball.png")

  -- Find available demos.
  local files =  love.filesystem.getDirectoryItems("examples")
	local n = 0

  for i, v in ipairs(files) do
    is_file = love.filesystem.isFile("examples/".. v )
    if is_file then
      n = n + 1
      table.insert(exf.available, v);
      local file = love.filesystem.newFile(v, love.file_read)
      file:open("r")
      local contents = love.filesystem.read("examples/" .. v, 100)
      local s, e, c = string.find(contents, "Example: ([%a%p ]-)[\r\n]")
      file:close(file)
      if not c then c = "Untitled" end
      local title = exf.getn(n) .. " " .. c .. " (" .. v .. ")"
      exf.list:add(title, v)
    end
  end

  exf.list:done()
  exf.resume()
end

function love.update(dt) end
function love.draw() end
function love.keypressed(k) end
function love.keyreleased(k) end
function love.mousepressed(x, y, b) end
function love.mousereleased(x, y, b) end
function exf.empty() end

function exf.update(dt)
  exf.list:update(dt)
	lightMouse:setPosition(love.mouse.getX(), love.mouse.getY())
end

function exf.draw()
	lightWorld:draw()
end

function exf.drawBackground()
  love.graphics.setBackgroundColor(0, 0, 0)

  love.graphics.setColor(48, 156, 225)
  love.graphics.rectangle("fill", 0, 0, love.window.getWidth(), love.window.getHeight())

  love.graphics.setColor(255, 255, 255, 191)
  love.graphics.setFont(exf.bigfont)
  love.graphics.print("Examples:", 50, 50)

  love.graphics.setFont(exf.smallfont)
  love.graphics.print("Browse and click on the example you \nwant to run. To return the the example \nselection screen, press escape.", 500, 80)

  exf.list:draw()
end

function exf.drawForeground()
  love.graphics.setColor(255, 255, 255)
  love.graphics.draw(exf.bigball, 800 - 128, 600 - 128, love.timer.getTime(), 1, 1, exf.bigball:getWidth() * 0.5, exf.bigball:getHeight() * 0.5)
end

function exf.keypressed(k)
end

function exf.keyreleased(k)
end

function exf.mousepressed(x, y, b)
  exf.list:mousepressed(x, y, b)
end

function exf.mousereleased(x, y, b)
  exf.list:mousereleased(x, y, b)
end

function exf.getn(n)
  local s = ""
  n = tonumber(n)
  local r = n
  if r <= 0 then error("Example IDs must be bigger than 0. (Got: " .. r .. ")") end
  if r >= 10000 then error("Example IDs must be less than 10000. (Got: " .. r .. ")") end
  while r < 1000 do
    s = s .. "0"
    r = r * 10
  end
  s = s .. n
  return s
end

function exf.intable(t, e)
  for k, v in ipairs(t) do
    if v == e then return true end
  end
  return false
end

function exf.start(item, file)
	local e_id = string.sub(item, 1, 4)
	local e_rest = string.sub(item, 5)
	local unused1, unused2, n = string.find(item, "(%s)%.lua")

	if exf.intable(exf.available, file) then
		if not love.filesystem.exists("examples/" .. file) then
			print("Could not load game .. " .. file)
		else

		-- Clear all callbacks.
		love.load = exf.empty
		love.update = exf.empty
		love.draw = exf.empty
		love.keypressed = exf.empty
		love.keyreleased = exf.empty
		love.mousepressed = exf.empty
		love.mousereleased = exf.empty

		love.filesystem.load("examples/" .. file)()
		exf.clear()

		--love.window.setTitle(e_rest)

		-- Redirect keypress
		local o_keypressed = love.keypressed
		love.keypressed =
		function(k)
			if k == "escape" then
				exf.resume()
			end
			o_keypressed(k)
		end

		love.load()
		end
	else
		print("Example ".. e_id .. " does not exist.")
	end
end

function exf.clear()
  love.graphics.setBackgroundColor(0,0,0)
  love.graphics.setColor(255, 255, 255)
	love.graphics.setLineWidth(1)
	love.graphics.setLineStyle("smooth")
  love.graphics.setBlendMode("alpha")
  love.mouse.setVisible(true)
end

function exf.resume()
  load = nil
  love.update = exf.update
  love.draw = exf.draw
  love.keypressed = exf.keypressed
  love.keyreleased = exf.keyreleased
  love.mousepressed = exf.mousepressed
  love.mousereleased = exf.mousereleased

  love.mouse.setVisible(true)
  love.window.setTitle("LOVE Example Browser")

	-- create light world
	lightWorld = LightWorld({
    drawBackground = exf.drawBackground,
    drawForeground = exf.drawForeground
  })
	lightWorld:setAmbientColor(127, 127, 127)

	-- create light
	lightMouse = lightWorld:newLight(0, 0, 255, 127, 63, 500)
	lightMouse:setSmooth(2)

	-- create shadow bodys
	circleTest = lightWorld:newCircle(800 - 128, 600 - 128, exf.bigball:getWidth()*0.5)
end

function inside(mx, my, x, y, w, h)
  return mx >= x and mx <= (x+w) and my >= y and my <= (y+h)
end


----------------------
-- List object
----------------------

List = {}

function List:new()
  o = {}
  setmetatable(o, self)
  self.__index = self

  o.items = {}
	o.files = {}

  o.x = 50
  o.y = 70

  o.width = 400
  o.height = 500

  o.item_height = 23
  o.sum_item_height = 0

  o.bar_size = 20
  o.bar_pos = 0
  o.bar_max_pos = 0
  o.bar_width = 15
  o.bar_lock = nil

  return o
end

function List:add(item, file)
	table.insert(self.items, item)
	table.insert(self.files, file)
end

function List:done()
  self.items.n = #self.items

  -- Recalc bar size.
  self.bar_pos = 0

  local num_items = (self.height/self.item_height)
  local ratio = num_items/self.items.n
  self.bar_size = self.height * ratio
  self.bar_max_pos = self.height - self.bar_size - 3

  -- Calculate height of everything.
  self.sum_item_height = (self.item_height+1) * self.items.n + 2
end

function List:hasBar()
  return self.sum_item_height > self.height
end

function List:getBarRatio()
  return self.bar_pos/self.bar_max_pos
end

function List:getOffset()
  local ratio = self.bar_pos/self.bar_max_pos
  return math.floor((self.sum_item_height-self.height)*ratio + 0.5)
end

function List:update(dt)
  if self.bar_lock then
	  local dy = math.floor(love.mouse.getY()-self.bar_lock.y+0.5)
	  self.bar_pos = self.bar_pos + dy

	  if self.bar_pos < 0 then
	    self.bar_pos = 0
	  elseif self.bar_pos > self.bar_max_pos then
	   self.bar_pos = self.bar_max_pos
	  end

	  self.bar_lock.y = love.mouse.getY()
  end
end

function List:mousepressed(mx, my, b)
  if self:hasBar() then
	  if b == "l" then
	    local x, y, w, h = self:getBarRect()
	    if inside(mx, my, x, y, w, h) then
	      self.bar_lock = { x = mx, y = my }
	    end
	  end

    local per_pixel = (self.sum_item_height-self.height)/self.bar_max_pos
    local bar_pixel_dt = math.floor(((self.item_height)*3)/per_pixel + 0.5)

	  if b == "wd" then
	    self.bar_pos = self.bar_pos + bar_pixel_dt
	    if self.bar_pos > self.bar_max_pos then 
        self.bar_pos = self.bar_max_pos 
      end
	  elseif b == "wu" then
	    self.bar_pos = self.bar_pos - bar_pixel_dt
	    if self.bar_pos < 0 then 
        self.bar_pos = 0 
      end
	  end
  end

  if b == "l" and inside(mx, my, self.x+2, self.y+1, self.width-3, self.height-3) then
    local tx, ty = mx-self.x, my + self:getOffset() - self.y
    local index = math.floor((ty/self.sum_item_height)*self.items.n)
    local i = self.items[index+1]
    local f = self.files[index+1]
    if f then
      exf.start(i, f)
    end
  end
end

function List:mousereleased(x, y, b)
  if self:hasBar() then
	  if b == "l" then
	    self.bar_lock = nil
	  end
  end
end

function List:getBarRect()
  return self.x+self.width+2, self.y+1+self.bar_pos,
	       self.bar_width-3, self.bar_size
end

function List:getItemRect(i)
	return self.x+2, self.y+((self.item_height+1)*(i-1)+1)-self:getOffset(),
	       self.width-3, self.item_height
end

function List:draw()
  love.graphics.setLineWidth(2)
  love.graphics.setLineStyle("rough")
  love.graphics.setFont(self.font)

  love.graphics.setColor(48, 156, 225)

  local mx, my = love.mouse.getPosition()

  -- Get interval to display.
  local start_i = math.floor( self:getOffset()/(self.item_height+1) ) + 1
  local end_i = start_i+math.floor( self.height/(self.item_height+1) ) + 1
  
  if end_i > self.items.n then 
    end_i = self.items.n 
  end

  love.graphics.setScissor(self.x, self.y, self.width, self.height)

  -- Items.
  for i = start_i,end_i do
    local x, y, w, h = self:getItemRect(i)
    local hover = inside(mx, my, x, y, w, h)

    if hover then
      love.graphics.setColor(0, 0, 0, 127)
    else
      love.graphics.setColor(0, 0, 0, 63)
    end

    love.graphics.rectangle("fill", x+1, y+i+1, w-3, h)

    if hover then
      love.graphics.setColor(255, 255, 255)
    else
      love.graphics.setColor(255, 255, 255, 127)
    end

    local e_id = string.sub(self.items[i], 1, 5)
    local e_rest = string.sub(self.items[i], 5)

    love.graphics.print(e_id, x+10, y+i+6)  --Updated y placement -- Used to change position of Example IDs
    love.graphics.print(e_rest, x+50, y+i+6) --Updated y placement -- Used to change position of Example Titles
  end

  love.graphics.setScissor()

  -- Bar.
  if self:hasBar() then
    local x, y, w, h = self:getBarRect()
    local hover = inside(mx, my, x, y, w, h)

    if hover or self.bar_lock then
      love.graphics.setColor(0, 0, 0, 127)
    else
      love.graphics.setColor(0, 0, 0, 63)
    end
    love.graphics.rectangle("fill", x, y, w, h)
  end

  -- Border.
  love.graphics.setColor(0, 0, 0, 63)
  love.graphics.rectangle("line", self.x+self.width, self.y, self.bar_width, self.height)
  love.graphics.rectangle("line", self.x, self.y, self.width, self.height)
end