class Erector::Output

# File lib/erector/output.rb, line 9
def initialize(options = {})
  @prettyprint = options.fetch(:prettyprint, AbstractWidget.prettyprint_default)
  @indentation = options.fetch(:indentation, 0)
  @current_line_length = 0
  @max_length = options[:max_length]
  @widgets = []

  @get_buffer = if options[:buffer] and options[:buffer].respond_to? :call
    options[:buffer]
  elsif options[:buffer]
    lambda { options[:buffer] }
  else
    buffer = []
    lambda { buffer }
  end
end

# File lib/erector/output.rb, line 30
def <<(s)
  # raise s.inspect unless s.is_a? String
  #
  s = s.to_s unless s.is_a? String
  append_indentation
  if @max_length && s.length + @current_line_length > @max_length
    leading_spaces = s =~ /^( +)/ ? $1.size : 0
    trailing_spaces = s =~ /( +)$/ ? $1.size : 0

    append(" " * leading_spaces)
    need_space = false
    words = s.split(/ /)
    words.each do |word|
      if (need_space ? 1 : 0) + word.length > space_left
        append_newline
        append_indentation
        need_space = false
      end
      append(" ") if need_space
      append(word)
      need_space = true
    end
    append(" " * trailing_spaces)
  else
    append(s)
  end
  self
end

# File lib/erector/output.rb, line 98
def append_newline
  buffer << "\n"
  @current_line_length = 0
end

# File lib/erector/output.rb, line 84
def at_line_start?
  @current_line_length == 0
end

# File lib/erector/output.rb, line 26
def buffer
  @get_buffer.call
end

# File lib/erector/output.rb, line 88
def indent
  @indentation += 1 if prettyprint
end

# File lib/erector/output.rb, line 103
def mark
  @mark = buffer.size
end

# File lib/erector/output.rb, line 78
def newline
  if prettyprint
    append_newline
  end
end

# File lib/erector/output.rb, line 64
def placeholder
  s = ""
  buffer << s
  s
end

# File lib/erector/output.rb, line 107
def rewind pos = @mark
  if buffer.kind_of?(Array)
    buffer.slice!(pos..-1)
  elsif (Object.const_defined?(:ActiveSupport) and
    buffer.kind_of?(ActiveSupport::SafeBuffer))
    # monkey patch to get around SafeBuffer's well-meaning paranoia
    # see http://yehudakatz.com/2010/02/01/safebuffers-and-rails-3-0/
    # and http://weblog.rubyonrails.org/2011/6/8/potential-xss-vulnerability-in-ruby-on-rails-applications
    String.instance_method(:slice!).bind(buffer).call(pos..-1)
  elsif buffer.kind_of?(String)
    buffer.slice!(pos..-1)
  else
    raise "Don't know how to rewind a #{buffer.class}"
  end

end

# File lib/erector/output.rb, line 74
def to_a
  buffer.kind_of?(Array) ? buffer : [buffer]
end

# File lib/erector/output.rb, line 70
def to_s
  RawString.new(buffer.kind_of?(String) ? buffer : buffer.join)
end

# File lib/erector/output.rb, line 92
def undent
  @indentation -= 1 if prettyprint
end

# File lib/erector/output.rb, line 126
def append(s)
  buffer << s
  @current_line_length += s.length
end

# File lib/erector/output.rb, line 135
def append_indentation
  if prettyprint and at_line_start?
    spaces = " " * ([@indentation, 0].max * SPACES_PER_INDENT)
    buffer << spaces
    @current_line_length += spaces.length
  end
end

# File lib/erector/output.rb, line 131
def space_left
  @max_length - @current_line_length
end