require "set"

require "browser/middleware"
require "browser/middleware/context"
require "browser/rails" if defined?(::Rails)

require "browser/methods/ie"
require "browser/methods/platform"
require "browser/methods/mobile"
require "browser/methods/devices"
require "browser/methods/language"

require "browser/meta/base"
require "browser/meta/generic_browser"
require "browser/meta/id"
require "browser/meta/ie"
require "browser/meta/ios"
require "browser/meta/mobile"
require "browser/meta/modern"
require "browser/meta/platform"
require "browser/meta/safari"
require "browser/meta/webkit"

class Browser
  include IE
  include Platform
  include Mobile
  include Devices
  include Language

  # Set browser's UA string.
  attr_accessor :user_agent
  alias :ua :user_agent
  alias :ua= :user_agent=

  NAMES = {
    :android    => "Android",
    :blackberry => "BlackBerry",
    :chrome     => "Chrome",
    :core_media => "Apple CoreMedia",
    :firefox    => "Firefox",
    :ie         => "Internet Explorer",
    :ipad       => "iPad",
    :iphone     => "iPhone",
    :ipod       => "iPod Touch",
    :opera      => "Opera",
    :phantom_js => "PhantomJS",
    :psp        => "PlayStation Portable",
    :quicktime  => "QuickTime",
    :safari     => "Safari",

    # This must be last item, since Ruby 1.9+ has ordered keys.
    :other      => "Other",
  }

  VERSIONS = {
    :default => %r[(?:Version|MSIE|Firefox|Chrome|CriOS|QuickTime|BlackBerry[^/]+|CoreMedia v|PhantomJS)[/ ]?([a-z0-9.]+)]i,
    :opera => %r[(?:Opera/.*? Version/([\d.]+)|Chrome/([\d.]+).*?OPR)]
  }

  # Create a new browser instance and set
  # the UA and Accept-Language headers.
  #
  #   browser = Browser.new({
  #     :ua => "Safari",
  #     :accept_language => "pt-br"
  #   })
  #
  def initialize(options = {}, &block)
    self.user_agent = (options[:user_agent] || options[:ua]).to_s
    self.accept_language = options[:accept_language].to_s

    yield self if block_given?
  end

  # Get readable browser name.
  def name
    NAMES[id]
  end

  # Get the browser identifier.
  def id
    NAMES.keys
      .find {|id| respond_to?("#{id}?") ? public_send("#{id}?") : id }
  end

  # Return major version.
  def version
    full_version.to_s.split(".").first
  end

  # Return the full version.
  def full_version
    _, *v = *ua.match(VERSIONS.fetch(id, VERSIONS[:default]))
    v.compact.first || "0.0"
  end

  # Return true if browser is modern (Webkit, Firefox 17+, IE9+, Opera 12+).
  def modern?
    webkit? ||
    (firefox? && version.to_i >= 17) ||
    (ie? && version.to_i >= 9) ||
    (opera? && version.to_i >= 12) ||
    (firefox? && tablet? && android? && version.to_i >= 14)
  end

  # Detect if browser is WebKit-based.
  def webkit?
    !!(ua =~ /AppleWebKit/i)
  end

  # Detect if browser is QuickTime
  def quicktime?
    !!(ua =~ /QuickTime/i)
  end

  # Detect if browser is Apple CoreMedia.
  def core_media?
    !!(ua =~ /CoreMedia/)
  end

  # Detect if browser is PhantomJS
  def phantom_js?
    !!(ua =~ /PhantomJS/)
  end

  # Detect if browser is Safari.
  def safari?
    ua =~ /Safari/ && ua !~ /Chrome|CriOS|PhantomJS/
  end

  # Detect if browser is Firefox.
  def firefox?
    !!(ua =~ /Firefox/)
  end

  # Detect if browser is Chrome.
  def chrome?
    !!(ua =~ /Chrome|CriOS/) && !opera?
  end

  # Detect if browser is Opera.
  def opera?
    !!(ua =~ /(Opera|OPR)/)
  end

  # Detect if browser is Silk.
  def silk?
    !!(ua =~ /Silk/)
  end

  # Return a meta info about this browser.
  def meta
    Meta.constants.each_with_object(Set.new) do |meta_name, meta|
      meta_class = Meta.const_get(meta_name)
      meta.merge(meta_class.new(self).to_a)
    end.to_a
  end

  alias_method :to_a, :meta

  # Return meta representation as string.
  def to_s
    meta.to_a.join(" ")
  end
end