#!/usr/bin/env ruby
# <xbar.title>Bluetooth Inspector</xbar.title>
# <xbar.version>0.1.4</xbar.version>
# <xbar.author>Ryan Scott Lewis</xbar.author>
# <xbar.author.github>RyanScottLewis</xbar.author.github>
# <xbar.desc>Show bluetooth information for all connected bluetooth devices using the `system_profiler` binary.</xbar.desc>
# <xbar.image>https://raw.githubusercontent.com/RyanScottLewis/bitbar-bluetooth_inspector/master/bitbar-bluetooth_inspector.png</xbar.image>
# <xbar.dependencies>ruby</xbar.dependencies>
# <xbar.abouturl>https://github.com/RyanScottLewis/bitbar-bluetooth_inspector</xbar.abouturl>

# NOTE: Configuration is at the BOTTOM of this file!

# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #
# -= Code -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #
# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #


require 'open3'

module BluetoothInspector

  # The plugin controller.
  class Controller

    class << self

      # Collect bluetooth devices, format for bitbar output, and print to output.
      #
      # @return [String]
      def run(&block)
        new.run(&block)
      end

    end

    def initialize
      collect_devices
      setup_formatter
    end

    # Get all devices.
    #
    # @return [<Device>]
    attr_reader :devices

    # Get the formatter.
    #
    # @return [Formatter]
    attr_reader :formatter

    # Collect bluetooth devices, format for bitbar output, and print to output.
    #
    # @return [String]
    def run(&block)
      run_config_block_if_needed(&block)

      output = @formatter.format(@devices)

      print output
    end

    protected

    def collect_devices
      stdout_str, _, _ = Open3.capture3("system_profiler SPBluetoothDataType")

      @devices = Parser.parse(stdout_str)
    end

    def setup_formatter
      @formatter = Formatter.new
    end

    def run_config_block_if_needed(&block)
      return nil unless block_given?

      block.arity > 0 ? yield(self) : run_in_controller_context(&block)
    end

    def run_in_controller_context(&block)
      ControllerContext.new(self).instance_eval(&block)
    end

  end

end

module BluetoothInspector

  # The DSL context for the configuration block given to the Controller.
  class ControllerContext

    def initialize(controller)
      @controller = controller
    end

    # Get all devices.
    #
    # @return [<Device>]
    def devices
      @controller.devices
    end

    # Find a device by it's name or shortname.
    #
    # @param [#to_s] value
    # @return [<Device>]
    def device(value, &block)
      value = value.to_s
      device = devices.find { |d| d.name == value || d.shortname == value }

      run_device_block_if_needed(device, &block)

      device
    end

    def bar_format(value)
      @controller.formatter.bar_format = value
    end

    def item_format(value)
      @controller.formatter.item_format = value
    end

    protected

    def run_device_block_if_needed(device, &block)
      return nil unless !device.nil? && block_given?

      block.arity > 0 ? yield(device) : run_in_device_context(device, &block)
    end

    def run_in_device_context(device, &block)
      DeviceContext.new(device).instance_eval(&block)
    end

  end

end

module BluetoothInspector

  # A bluetooth device.
  class Device
    def initialize(attributes={})
      @bar_item = true
      @menu_item = true

      update_attributes(attributes)

      raise "name must be given" if @name.nil?
    end

    # Get the name of the device.
    #
    # @return [String]
    attr_reader :name

    # Set the name of the device.
    #
    # @param [#to_s] value
    # @return [String]
    def name=(value)
      @name = value.to_s
    end

    # Get the major type of the device.
    #
    # @return [String]
    attr_reader :major_type

    # Set the major_type of the device.
    #
    # @param [#to_s] value
    # @return [String]
    def major_type=(value)
      @major_type = value.to_s
    end

    # Get the minor type of the device.
    #
    # @return [String]
    attr_reader :minor_type

    # Set the minor_type of the device.
    #
    # @param [#to_s] value
    # @return [String]
    def minor_type=(value)
      @minor_type = value.to_s
    end

    # Get whether the device is paired.
    #
    # @return [Boolean]
    def paired?
      @paired
    end

    # Get whether the device is not paired.
    #
    # @return [Boolean]
    def unpaired?
      !@paired
    end

    # set whether the device is paired.
    #
    # @param [Boolean] value
    # @return [Boolean]
    def paired=(value)
      @paired = !!value
    end

    # Get whether the device is connected.
    #
    # @return [Boolean]
    def connected?
      @connected
    end

    # Get whether the device is not connected.
    #
    # @return [Boolean]
    def disconnected?
      !@connected
    end

    # set whether the device is connected.
    #
    # @param [Boolean] value
    # @return [Boolean]
    def connected=(value)
      @connected = !!value
    end

    # Get the shortname of the device.
    #
    # @return [nil, String]
    def shortname
      @shortname.nil? ? @name : @shortname
    end

    # Set the shortname of the device.
    #
    # @param [nil, #to_s] value
    # @return [nil, String]
    def shortname=(value)
      @shortname = value.nil? ? nil : value.to_s
    end

    # Get whether this device has a shortname.
    #
    # @return [Boolean]
    def shortname?
      !@shortname.nil?
    end

    # Get the battery level in a range of `0..100`.
    #
    # @return [nil, Float]
    attr_reader :battery

    # Set the battery level in a range of `0..100`.
    #
    # @param [nil, #to_f] value
    # @return [nil Float]
    def battery=(value)
      @battery = value.nil? ? nil : value.to_i
    end

    # Get whether this device has no battery level.
    #
    # @return [Boolean]
    def no_battery?
      @battery.nil?
    end

    # Get whether this device has a battery level.
    #
    # @return [Boolean]
    def battery?
      !no_battery?
    end

    # Get the color of the device.
    #
    # @return [nil, String]
    attr_reader :color

    # Set the name of the device.
    #
    # @param [nil, #to_s] value
    # @return [nil, String]
    def color=(value)
      @color = value.nil? ? nil : value.to_s
    end

    # Get whether this device has a color.
    #
    # @return [Boolean]
    def color?
      !@color.nil?
    end

    # Get whether this device is shown within the bar.
    #
    # @return [Boolean]
    def bar_item?
      @bar_item
    end

    # Set whether this device is shown within the bar.
    #
    # @param [Boolean] value
    # @return [Boolean]
    def bar_item=(value)
      @bar_item = !!value
    end

    # Get whether this device is shown within the menu.
    #
    # @return [Boolean]
    def menu_item?
      @menu_item
    end

    # Set whether this device is shown within the menu.
    #
    # @param [Boolean] value
    # @return [Boolean]
    def menu_item=(value)
      @menu_item = !!value
    end

    # Get device's attributes.
    #
    # @return [Hash]
    def to_h
      {
        name:      @name,
        shortname: @shortname,
        battery:   @battery
      }
    end

    protected

    def update_attributes(attributes)
      attributes.to_h.each do |name, value|
        next unless self.class.method_defined?("#{name}=")

        send("#{name}=", value)
      end
    end

  end

end

module BluetoothInspector

  # The DSL context for a device.
  class DeviceContext

    def initialize(device)
      @device = device
    end

    # Get the device.
    #
    # @param [String]
    # @return [String]
    attr_reader :device

    # Get/set the name of the device.
    #
    # @param [String]
    # @return [String]
    def name(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    # Get/set the major type of the device.
    #
    # @param [String]
    # @return [String]
    def major_type(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    # Get/set the minor type of the device.
    #
    # @param [String]
    # @return [String]
    def minor_type(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    # Get/set whether the device is paired.
    #
    # @param [String]
    # @return [String]
    def paired?(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    # Get/set whether the device is connected.
    #
    # @param [String]
    # @return [String]
    def connected?(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    # Get/set the shortname of the device.
    #
    # @return [nil, String]
    def shortname(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    # Get/set the battery level of the device.
    #
    # @return [nil, Integer]
    def battery(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    # Get/set the color of the device.
    #
    # @return [nil, String]
    def color(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    # Get/set whether the device is shown within the bar.
    #
    # @return [Boolean]
    def bar_item(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    # Get/set whether the device is shown within the menu.
    #
    # @return [Boolean]
    def menu_item(*arguments)
      get_or_set_attribute(__method__, arguments)
    end

    protected

    def validate_arguments(arguments)
      raise ArgumentError, "wrong number of arguments (given #{arguments.count}, expected 0..1)" if arguments.length > 1
    end

    def get_or_set_attribute(name, arguments)
      validate_arguments(arguments)

      arguments.empty? ? @device.send(name) : @device.send("#{name}=", arguments.first)
    end

  end

end

module BluetoothInspector

  # Formats a list of devices for the expected bitbar output.
  class Formatter

    def initialize
      @bar_format = ":shortname :battery%"
      @item_format = ":name"
    end

    # Get the format for a device as a bar item.
    #
    # @return [String]
    attr_reader :bar_format

    # Set the format for a device as a bar item.
    #
    # @param [#to_s] value
    # @return [String]
    def bar_format=(value)
      @bar_format = value.to_s
    end

    # Get the format for a device as a menu item.
    #
    # @return [String]
    attr_reader :item_format

    # Set the format for a device as a menu item.
    #
    # @param [#to_s] value
    # @return [String]
    def item_format=(value)
      @item_format = value.to_s
    end

    def format(devices)
      lines = []

      devices.find_all(&:bar_item?).each { |device| lines << format_device(@bar_format, device) }

      lines << "---"
      devices.find_all(&:menu_item?).each { |device| lines << format_device(@item_format, device) }

      lines.join("\n")
    end

    protected

    def format_device(format_string, device)
      output = format_string
      device.to_h.each { |name, value| output = output.gsub(/:#{name}/, value.to_s) }

      device.color.nil? ? output : output + " | color=#{device.color}"
    end

  end

end

require "yaml"

module BluetoothInspector

  # Parses the output of the `system_profiler` command and returns an Array of Device instances.
  class Parser

    class << self

      # Parse the command output.
      #
      # @param [#to_s] data The command output.
      # @return [<Device>]
      def parse(data)
        new.parse(data)
      end

    end

    # Parse the command output.
    #
    # @param [#to_s] data The command output.
    # @return [<Device>]
    def parse(data)
      data = YAML.load(data.to_s)

      data["Bluetooth"]["Connected"].collect do |name, attributes|
        Device.new(
          name:       name,
          battery:    attributes["Battery Level"],
          major_type: attributes["Major Type"],
          minor_type: attributes["Minor Type"],
          paired:     attributes["Paired"],
          connected:  true,
        )
      end
    end

  end

end

module BluetoothInspector

  class << self

    # Run the plugin controller.
    def run(&block)
      Controller.run(&block)
    end

  end

end


# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #
# -= Configuration =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #
# -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- #

# See https://github.com/RyanScottLewis/bitbar-bluetooth_inspector for configuration documentation.

BluetoothInspector.run do
  devices.delete_if(&:no_battery?)
  devices.delete_if(&:disconnected?)

  # Color all low battery level devices red:
  devices.find_all { |device| device.battery < 20 }.each { |device| device.color = "red" }

  # Add device emojis to each shortname
  devices.each do |device|
    device.shortname = case device.minor_type
                            when 'Mouse'    then '🖱'
                            when 'Keyboard' then '⌨️'
                       end
  end
end
