piotrmurach/strings-ansi

# frozen_string_literal: true

require_relative "ansi/version"

module Strings
  # Helper functions for handling ANSI escape sequences
  module ANSI
    # The control sequence indicator
    CSI = "\033"

    # The code for reseting styling
    RESET = "\e[0m"

    # The regex to match ANSI codes
    ANSI_MATCHER = %r{
      (?>\033(
        \[[\[?>!]?\d*(;\d+)*[ ]?[a-zA-Z~@$^\]_\{\\] # graphics
        |
        \#?\d # cursor modes
        |
        [)(%+\-*/. ](\d|[a-zA-Z@=%]|) # character sets
        |
        O[p-xA-Z] # special keys
        |
        [a-zA-Z=><~\}|] # cursor movement
        |
        \]8;[^;]*;.*?(\033\\|\07) # hyperlink
      ))
    }x.freeze

    # Return a copy of string with ANSI characters removed
    #
    # @param [String] string
    #
    # @example
    #   Strings::ANSI.sanitize("\e[33mfoo\[e0m")
    #   # => "foo"
    #
    # @return [String]
    #
    # @api public
    def sanitize(string)
      string.gsub(ANSI_MATCHER, "")
    end
    module_function :sanitize

    # Check if string contains ANSI codes
    #
    # @param [String] string
    #   the string to check
    #
    # @example
    #   Strings::ANSI.ansi?("\e[33mfoo\[e0m")
    #   # => true
    #
    # @return [Boolean]
    #
    # @api public
    def ansi?(string)
      !!(string =~ ANSI_MATCHER)
    end
    module_function :ansi?

    # Check if string contains only ANSI codes
    #
    # @param [String] string
    #   the string to check
    #
    # @example
    #   Strings::ANSI.only_ansi?("\e[33mfoo\[e0m")
    #   # => false
    #
    #   Strings::ANSI.only_ansi?("\e[33m")
    #   # => false
    #
    # @return [Boolean]
    #
    # @api public
    def only_ansi?(string)
      !!(string =~ /\A(#{ANSI_MATCHER})+\z/)
    end
    module_function :only_ansi?
  end # ANSI
end # Strings