asciinema.org/app/assets/javascripts/player/brush.js.coffee

class AsciiIo.Brush
  @default_fg = 7
  @default_bg = 0

  @cache: {}

  @clearCache: ->
    @cache = {}

  @default: ->
    @_default ||= @create()

  @hash: (brush) ->
    "#{brush.fg}_#{brush.bg}_#{brush.blink}_#{brush.bright}_#{brush.italic}_#{brush.underline}_#{brush.reverse}"

  @create: (options = {}) ->
    key = @hash options
    brush = @cache[key]

    if not brush
      brush = new AsciiIo.Brush(options)
      @cache[key] = brush

    brush

  constructor: (options = {}) ->
    @fg        = undefined
    @bg        = undefined
    @blink     = false
    @bright    = false
    @italic    = false
    @underline = false
    @reverse   = false

    for name, value of options
      this[name] = value

  hash: ->
    AsciiIo.Brush.hash this

  attributes: ->
    fg       : @fg
    bg       : @bg
    blink    : @blink
    bright   : @bright
    italic   : @italic
    underline: @underline
    reverse  : @reverse

  fgColor: ->
    if @reverse
      @calculateBgColor()
    else
      @calculateFgColor()

  bgColor: ->
    if @reverse
      @calculateFgColor()
    else
      @calculateBgColor()

  calculateFgColor: ->
    color = @fg
    color = AsciiIo.Brush.default_fg if color is undefined
    color += 8 if color < 8 and @bright
    color

  calculateBgColor: ->
    color = @bg
    color = AsciiIo.Brush.default_bg if color is undefined
    color += 8 if color < 8 and @blink
    color

  applyChanges: (changes) ->
    attrs = @attributes()

    for attr, val of changes
      attrs[attr] = val

    AsciiIo.Brush.create attrs

  hasDefaultFg: ->
    @fgColor() == AsciiIo.Brush.default_fg

  hasDefaultBg: ->
    @bgColor() == AsciiIo.Brush.default_bg