local Object = require "lib/classic"

local NineSlice = Object:extend()

function NineSlice:new(atlas, sprites)
  self.atlas = atlas
  self.sprites = sprites
end

function NineSlice:draw(x, y, width, height)
  local function draw(sprite, tx, ty)
    local atlas = self.atlas
    local sw = atlas.sw
    local sh = atlas.sh
    local gx = x + tx * sw
    local gy = y + ty * sh

    if sprite then
      atlas:draw(sprite, gx, gy)
    else
      love.graphics.rectangle("fill", gx, gy, sw, sh)
    end
  end

  --common variables
  local right = width - 1
  local bottom = height - 1
  local sprites = self.sprites

  if width == 1 and height == 1 then
    draw(sprites.only_center, 0, 0)
  elseif width == 1 then
    draw(sprites.vert_top, 0, 0)
    draw(sprites.vert_bottom, 0, bottom)

    for cy = 1, bottom - 1 do
      draw(sprites.vert_center, 0, cy)
    end
  elseif height == 1 then
    draw(sprites.hori_left, 0, 0)
    draw(sprites.hori_right, right, 0)

    for cx = 1, right - 1 do
      draw(sprites.hori_center, cx, 0)
    end
  else
    --draw corners
    draw(sprites.tl, 0, 0)
    draw(sprites.tr, right, 0)
    draw(sprites.bl, 0, bottom)
    draw(sprites.br, right, bottom)

    --horizontal edges
    for cx = 1, right - 1 do
      draw(sprites.top, cx, 0)
      draw(sprites.bottom, cx, bottom)
    end

    --vertical edges
    for cy = 1, bottom - 1 do
      draw(sprites.left, 0, cy)
      draw(sprites.right, right, cy)
    end

    --draw center
    for cx = 1, right - 1 do
      for cy = 1, bottom - 1 do
        draw(sprites.center, cx, cy)
      end
    end
  end
end

return NineSlice