require 'uri'

#### jsrb.rb <https://github.com/tmtm/jsrb/>
require 'js'

# JS を Ruby ぽく扱えるようにする
class JSrb
  def self.global
    @global ||= JSrb.new(JS.global)
  end

  def self.window
    @window ||= global[:window]
  end

  def self.document
    @document ||= global[:document]
  end

  # @param sec [Numeric] seocnd
  def self.timeout(sec, &block)
    JS.global.setTimeout(->{Fiber.new{block.call}.transfer if block}, sec * 1000)
  end

  # @param v [JS::Object]
  # @return [Object]
  def self.convert(v)
    return nil if v == JS::Null || v == JS::Undefined

    case v.typeof
    when 'number'
      return v.to_s =~ /\./ ? v.to_f : v.to_i
    when 'bigint'
      return v.to_i
    when 'string'
      return v.to_s
    when 'boolean'
      return v == JS::True
    end

    if v[:constructor] == JS.global[:Array]
      v[:length].to_i.times.map{|i| JSrb.convert(v[i])}
    elsif v[:length].typeof == 'number' && v[:item].typeof == 'function'
      v = JSrb.new(v)
      v.extend JSrb::Enumerable
      v
    elsif v[:constructor] == JS.global[:Date]
      Time.new(v.toISOString.to_s)
    else
      JSrb.new(v)
    end
  end

  # @param obj [JS::Object]
  def initialize(obj)
    @obj = obj
  end

  # hoge_fuga を hogeFuga に変換して JavaScript を呼び出し、
  # 値を JS::Object から Ruby に変換して返す
  def method_missing(sym, *args, &block)
    jssym = sym.to_s.gsub(/_([a-z])/){$1.upcase}.intern
    jsargs = args.map{|a| a.is_a?(JSrb) ? a.js_object : a}
    jsblock = block ? proc{|*v| block.call(*v.map{JSrb.convert(_1)})} : nil
    if jssym.end_with? '='
      return @obj.__send__(jssym, *jsargs, &jsblock) if @obj.respond_to? jssym
      return @obj.__send__(:[]=, jssym.to_s.chop.intern, *jsargs, &jsblock)
    end
    v = @obj[jssym]
    if v.typeof == 'function'
      JSrb.convert(@obj.call(jssym, *jsargs, &jsblock))
    elsif v == JS::Undefined && @obj.respond_to?(jssym)
      JSrb.convert(@obj.__send__(jssym, *jsargs, &jsblock))
    elsif v != JS::Undefined && args.empty?
      JSrb.convert(v)
    else
      super
    end
  end

  def respond_to_missing?(sym, include_private)
    return true if super
    return true if @obj.respond_to? sym
    jssym = sym.to_s.sub(/=$/, '').gsub(/_([a-z])/){$1.upcase}.intern
    @obj[sym] != JS::Undefined || @obj[jssym] != JS::Undefined
  end

  def to_s
    @obj.to_s
  end

  def to_i
    @obj.to_i
  end

  def to_h
    JSrb.window[:Object].entries(@obj).to_h
  end

  def inspect
    "#<JSrb: #{@obj.inspect}>"
  end

  # @param sym [Symbol]
  # @return [Object]
  def [](sym)
    JSrb.convert(@obj[sym])
  end

  # @return [JS::Object]
  def js_object
    @obj
  end

  private

  module Enumerable
    include ::Enumerable

    def each
      i = 0
      while i < length
        yield self.item(i)
        i += 1
      end
    end

    def size
      length
    end

    def empty?
      length == 0
    end

    def last
      self[length - 1]
    end
  end
end
####

def create_element(tag, **attrs)
  e = @document.create_element(tag)
  attrs.each do |n, v|
    e.set_attribute(n.to_s, v)
  end
  e
end

def draw
  unless @start_time
    if current == 0
      @document.cookie = "rabbit_start_time=0;max-age=0"
    end
    if @document.cookie =~ /\Arabbit_start_time=(\d+)/
      @start_time = $1.to_i
    else
      @start_time = Time.now.to_i
      @document.cookie = "rabbit_start_time=#{@start_time};max-age=3600"
    end
  end

  parent.append_child(@img_turtle)
  parent.append_child(@img_rabbit)

  parent_width = @body.client_width
  width = parent_width - @img_rabbit.width
  left = width * current
  @img_rabbit.style.left = "#{left}px"
  @img_rabbit.style.transform = nil
  if @allotted_time == 0
    @img_turtle.style.visibility = 'hidden'
    return
  end

  width = parent_width - @img_turtle.width
  left = width * (Time.now.to_f - @start_time) / (@allotted_time * 60)
  @img_turtle.style.transform = nil
  if left < parent_width + 200
    @img_turtle.style.left = "#{left}px"
    @img_turtle.style.visibility = 'visible'
  else
    @img_turtle.style.visibility = 'hidden'
  end
end

def create_dialog
  @dialog = create_element(
    'div',
    id: 'dialog',
    style: 'position:fixed;; top:0; left:0; display:none; padding:10px; border:solid 1px #000; z-index:10000; background-color:#fff'
  )
  @dialog.innerHTML = <<~HTML
    <label>Allotted time (min)
        <input type="number" id="allotted_time" min="0" value="#{@allotted_time}">
        <a id="close_dialog">🞪</a><br>
        <input type="button" id="reset_turtle-button" value="Reset Turtle">
    </label>
  HTML
  @body.append_child(@dialog)
  @document.query_selector('#allotted_time').add_event_listener('change') do |ev|
    @allotted_time = ev.target.value.to_i
  end
  @document.query_selector('#close_dialog').add_event_listener('click') do
    @dialog.style.display = 'none'
  end
  @document.query_selector('#reset_turtle-button').add_event_listener('click') do
    @start_time = Time.now.to_i
    @document.cookie = "rabbit_start_time=#{@start_time};max-age=86400"
  end
end

def start
  unless @started
    uri = URI.parse(JSrb.window.location.to_s)
    if uri.host == 'speakerdeck.com'
      include SpeakerDeck
    elsif JSrb.document.query_selector('div.pdfViewer')
      include PDFViewer
    else
      include RevealJS
    end
    q = URI.decode_www_form(uri.query.to_s).to_h
    @allotted_time ||= q['allotted_time'].to_i
    @document = document
    @body = @document.query_selector('body')
    create_dialog
    @img_rabbit = create_element(
      'img',
      id: 'rabbit-rabbit',
      style: 'position:fixed; bottom:0px; left:0px; width:5%; margin:2px',
      src: 'https://tmtms.net/rabbit/rabbit.png'
    )
    @img_rabbit.style.visibility = 'hidden' if @document.query_selector('.print-pdf')
    @img_rabbit.add_event_listener('click') do
      @dialog.style.display = @dialog.style[:display] == 'block' ? 'none' : 'block'
    end
    @img_turtle = create_element(
      'img',
      id: 'rabbit-turtle',
      style: 'position:fixed; bottom:0px; left:0px; width:5%; margin:2px; visibility:hidden',
      src: 'https://tmtms.net/rabbit/turtle.png'
    )
    @started = true
  end

  if current == 0 && @start_time
    @start_time = Time.now.to_i
    @document.cookie = "rabbit_start_time=#{@start_time};max-age=86400"
  end

  JSrb.window.clear_interval(@interval_id) if @interval_id
  @interval_id = JSrb.window.set_interval(->{draw}, 300)
end

module RevealJS
  def parent
    @body
  end

  def current
    slides = @document.query_selector_all('div.slides section').to_a
    current_page = slides.index{|v| v.get_attribute('class') == 'present'} || 0
    current_page.to_f / (slides.size - 1)
  end

  def document
    JSrb.document
  end
end

module SpeakerDeck
  def parent
    @body.query_selector('div.is-fullscreen') ? @body.query_selector('div.js-sd-player-current-slide') : @body
  end

  def current
    @body.query_selector('div.sd-player-scrubber-progress').style.width.to_f / 100.0
  end

  def document
    JSrb.document.query_selector('iframe.speakerdeck-iframe').content_document
  end
end

module PDFViewer
  def parent
    document.get_element_by_id('viewerContainer')
  end

  def current
    page = @document.get_element_by_id('pageNumber')
    cur = page.value.to_i - 1
    max = page.max.to_i - 1
    cur.to_f / max
  end

  def document
    JSrb.document
  end
end

start