ioquatix/build-text

# Copyright, 2013, by Samuel G. D. Williams. <http://www.codeotaku.com>
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

module Build
    module Text
        class Indentation
            TAB = "\t".freeze
            
            def initialize(prefix, level, indent)
                @prefix = prefix
                @level = level
                @indent = indent
            end

            def freeze
                indentation
                
                @prefix.freeze
                @level.freeze
                @indent.freeze
                
                super
            end

            def indentation
                @indentation ||= @prefix + (@indent * @level)
            end

            def + other
                indentation + other
            end

            def << text
                text.gsub(/^/){|m| m + indentation}
            end

            def by(depth)
                Indentation.new(@prefix, @level + depth, @indent)
            end
            
            def with_prefix(prefix)
                Indentation.new(prefix, @level, @indent)
            end
            
            def self.none
                self.new('', 0, TAB)
            end
        end
    end
end