Class: ANSIStyleManager

Inherits:
Object
  • Object
show all
Defined in:
lib/utils/ansi_style_manager.rb

Overview

The ANSIStyleManager class is responsible for managing and applying ANSI styles to a given string.

It can replace tokens in the string with corresponding ANSI codes for colors, backgrounds and effects.

Effects

Effects can be used by adding <effect:effect_name> at the beginning and </effect> at the end of the sequence of characters to which you want the effect to be applied.

Example:

manager = ANSIStyleManager.new('The text <effect:bold>Potato</effect> will be bold.')
puts manager

Output:

bold output

Below is the table with all available effects:

Effect Name Description
bold set bold mode.
faint set dim/faint mode.
italic set italic mode.
underline set underline mode.
blinking set blinking mode.
inverse set inverse/reverse mode.
hidden set hidden/invisible mode.
strike set strikethrough mode.
plain set double underline mode.

Note: Some terminals may not support some of the effects listed above.

Colors

The ANSIStyleManager supports 3 types of coloring: Named Colors, RGB Colors, or 256 Colors.

The foreground color can be changed by adding <color:color_type> at the beginning and </color> at the end of the character sequence you want to color.

Example:

text  = 'A <color:green>colorful <color:red>world <color:yellow>is <color:blue>much '
text += '</color>more </color>beautiful</color>!</color> ;)'
manager = ANSIStyleManager.new(text)
puts manager

Output:

colored output

It is also possible to set the background color of a text.

The background color can be changed by adding <color:color_type:color_type> at the beginning and </color> at the end of the character sequence you want to color.

Example:

text  = 'A <color:green:white>colorful <color:196>world <color:yellow:111>is <color:blue:255;255;255>much '
text += '</color>more </color>beautiful</color>!</color> ;)'
manager = ANSIStyleManager.new(text)
puts manager

Output:

colored output

Below is the table with all available color type patterns:

Color Type Pattern Description
Reset colors reset Resets to the terminal's default color.
256 Colors number Accepts numbers between 0 and 255.
RGB Colors R;G;B R, G, and B accept values between 0 and 255.
Named Colors name Accepts the following color names: black, red, green, yellow, blue, magenta, cyan and white.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(string) ⇒ ANSIStyleManager

Initializes a new instance of the ANSIStyleManager class.

Parameters:

  • string (String) —

    The string to which ANSI styles will be applied.

Raises:

  • (RuntimeError) —

    If the argument is not a string.



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# File 'lib/utils/ansi_style_manager.rb', line 90

def initialize(string)
  raise 'Need initialize with a string' unless string.is_a?(String)

  @string = String.new(string)
end

Instance Attribute Details

#string ⇒ String (readonly)

Returns the string to which ANSI styles will be applied.

Returns:

  • (String) —

    the string to which ANSI styles will be applied.



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# File 'lib/utils/ansi_style_manager.rb', line 84

def string
  @string
end

Instance Method Details

#replace_all_tokens! ⇒ void

This method returns an undefined value.

Replaces all color and effect tokens in the string with corresponding ANSI codes.



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# File 'lib/utils/ansi_style_manager.rb', line 99

def replace_all_tokens!
  replace_color_tokens!
  replace_effect_tokens!
end

#replace_color_tokens! ⇒ void

This method returns an undefined value.

Replaces all color tokens in the string with corresponding ANSI codes.



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# File 'lib/utils/ansi_style_manager.rb', line 107

def replace_color_tokens!
  scan_while_find(CONSTANTS::ANSI::COLORS) do |value|
    colors = value.first.split(':')

    replace_tokens_with!(
      ansi_token: color_prefix(color: colors[0], background: colors[1]),
      ansi_reset_token: ANSI.new(%i[reset_background reset_color]),
      to_replace: "<color:#{value.first}>#{value.last}</color>",
      preserve_reset_token: false,
      text: value.last
    )
  end
end

#replace_effect_tokens! ⇒ void

This method returns an undefined value.

Replaces all effect tokens in the string with corresponding ANSI codes.



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# File 'lib/utils/ansi_style_manager.rb', line 124

def replace_effect_tokens!
  scan_while_find(CONSTANTS::ANSI::EFFECTS) do |value|
    replace_tokens_with!(
      ansi_reset_token: ANSI.new("remove_#{value.first.downcase}"),
      to_replace: "<effect:#{value.first}>#{value.last}</effect>",
      ansi_token: ANSI.new(value.first.downcase),
      preserve_reset_token: true,
      text: value.last
    )
  end
end

#to_s ⇒ String

Converts the string with all tokens replaced by corresponding ANSI codes.

Returns:

  • (String) —

    The string with ANSI codes applied.



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# File 'lib/utils/ansi_style_manager.rb', line 139

def to_s
  replace_all_tokens!
  @string
end