#!ruby
# -*- mode: ruby; coding: utf-8 -*-
# Last updated: <2018/02/17 06:32:52 +0900>
#
# Tiledからエクスポートしたjsonを読み込んでDXRubyで描画する

# require 'dxopal'
# include DXOpal

require 'dxruby'
require 'json'

# Image.register(:bgchip, 'images/bg_attari.png')

# DXOpal
def json_to_hash_dxopal(url)
  req = Native(`new XMLHttpRequest()`)
  req.overrideMimeType("text/plain")
  req.open("GET", url, false)
  req.send
  text_data = req.responseText
  return Native(`JSON.parse(text_data)`)
end

# DXRuby
def json_to_hash_dxruby(url)
  json_text = File.open(url) {|f| f.read }
  return JSON.load(json_text)
end

def get_map_data_from_json(json_file)
  # res = json_to_hash_dxopal(json_file)
  res = json_to_hash_dxruby(json_file)

  d = {}
  d[:tilewidth] = res["tilewidth"]
  d[:tileheight] = res["tileheight"]
  d[:width] = res["width"]
  d[:height] = res["height"]

  layers = {}
  res["layers"].each do |layer|
    name = layer["name"]
    w = layer["width"]
    h = layer["height"]
    org_data = layer["data"]
    layers[name] = Array.new(h){ Array.new(w) }
    h.times do |y|
      w.times do |x|
        code = org_data[y * w + x] - 1
        layers[name][y][x] = (code < 0)? nil : code
      end
    end
  end
  d[:layers] = layers

  return d
end

def draw_tile(x, y, map_array, imgs, start_x, start_y, x_cnt, y_cnt)
  ofs_x = x
  ofs_y = y
  tile_w = imgs[0].width
  tile_h = imgs[0].height
  bg_h = map_array.length
  bg_w = map_array[0].length
  start_x = start_x % (tile_w * bg_w)
  start_y = start_y % (tile_h * bg_h)
  x_mod = (start_x % tile_w).to_i
  y_mod = (start_y % tile_h).to_i
  x_index = (start_x / tile_w).to_i
  y_index = (start_y / tile_h).to_i
  y_cnt.times do |y|
    x_cnt.times do |x|
      ix = (x_index + x).to_i % bg_w
      iy = (y_index + y).to_i % bg_h
      code = map_array[iy][ix]
      next if code.nil?
      px = ofs_x + (x * tile_w) - x_mod
      py = ofs_y + (y * tile_h) - y_mod
      Window.draw(px, py, imgs[code])
    end
  end
end

def game_main(img)
  imgs = img.slice_tiles(img.width / 16, img.height / 16)

  # mapdata = get_map_data_from_json("mapdata/bg_atari_test.json")
  mapdata = get_map_data_from_json("bg_atari_test.json")
  x_cnt = Window.width / mapdata[:tilewidth] + 1
  y_cnt = Window.height / mapdata[:tileheight] + 1
  bg_x, bg_y = 0, 0
  ofs_x, ofs_y = 0, 0

  Window.bgcolor = [32, 64, 128]

  Window.loop do
    break if Input.keyPush?(K_ESCAPE)

    if false
      a = 8
      bg_x -= a if Input.keyDown?(K_LEFT)
      bg_x += a if Input.keyDown?(K_RIGHT)
      bg_y -= a if Input.keyDown?(K_UP)
      bg_y += a if Input.keyDown?(K_DOWN)
    else
      bg_x += 3
      bg_y += 1
    end

    layer_names = ["layer3", "layer2", "layer1", "layer0"]
    spd = 0.25
    layer_names.each do |name|
      x = bg_x * spd
      y = bg_y * spd
      map_data = mapdata[:layers][name]

      # Window.draw_tile(ofs_x, ofs_y, map_data, imgs, x, y, x_cnt, y_cnt)
      draw_tile(ofs_x, ofs_y, map_data, imgs, x, y, x_cnt, y_cnt)

      spd += 0.25
    end

    Window.draw_font(2, 2, "#{Window.real_fps} FPS", Font.default)
    Window.draw_font(2, 32, "bg x,y = #{bg_x}, #{bg_y}", Font.default)
  end
end

# Window.load_resources do
img = Image.load("bg_attari.png")
# img = Image[:bgchip]
game_main(img)
# end