module Haml::Compiler

def self.build_attributes(is_html, attr_wrapper, escape_attrs, attributes = {})

This is a class method so it can be accessed from Buffer.
def self.build_attributes(is_html, attr_wrapper, escape_attrs, attributes = {})
  quote_escape = attr_wrapper == '"' ? """ : "'"
  other_quote_char = attr_wrapper == '"' ? "'" : '"'
  if attributes['data'].is_a?(Hash)
    attributes = attributes.dup
    attributes =
      Haml::Util.map_keys(attributes.delete('data')) {|name| "data-#{name}"}.merge(attributes)
  end
  result = attributes.collect do |attr, value|
    next if value.nil?
    value = filter_and_join(value, ' ') if attr == 'class'
    value = filter_and_join(value, '_') if attr == 'id'
    if value == true
      next " #{attr}" if is_html
      next " #{attr}=#{attr_wrapper}#{attr}#{attr_wrapper}"
    elsif value == false
      next
    end
    escaped =
      if escape_attrs == :once
        Haml::Helpers.escape_once(value.to_s)
      elsif escape_attrs
        Haml::Helpers.html_escape(value.to_s)
      else
        value.to_s
      end
    value = Haml::Helpers.preserve(escaped)
    if escape_attrs
      # We want to decide whether or not to escape quotes
      value = value.gsub('"', '"')
      this_attr_wrapper = attr_wrapper
      if value.include? attr_wrapper
        if value.include? other_quote_char
          value = value.gsub(attr_wrapper, quote_escape)
        else
          this_attr_wrapper = other_quote_char
        end
      end
    else
      this_attr_wrapper = attr_wrapper
    end
    " #{attr}=#{this_attr_wrapper}#{value}#{this_attr_wrapper}"
  end
  result.compact.sort.join
end

def self.filter_and_join(value, separator)

def self.filter_and_join(value, separator)
  return "" if value == ""
  value = [value] unless value.is_a?(Array)
  value = value.flatten.collect {|item| item ? item.to_s : nil}.compact.join(separator)
  return !value.empty? && value
end

def compile(node)

def compile(node)
  parent, @node = @node, node
  if node.children.empty?
    send(:"compile_#{node.type}")
  else
    send(:"compile_#{node.type}") {node.children.each {|c| compile c}}
  end
ensure
  @node = parent
end

def compile_comment

def compile_comment
  open = "<!--#{@node.value[:conditional]}"
  # Render it statically if possible
  unless block_given?
    push_text("#{open} #{@node.value[:text]} #{@node.value[:conditional] ? "<![endif]-->" : "-->"}")
    return
  end
  push_text(open, 1)
  @output_tabs += 1
  yield if block_given?
  @output_tabs -= 1
  push_text(@node.value[:conditional] ? "<![endif]-->" : "-->", -1)
end

def compile_doctype

def compile_doctype
  doctype = text_for_doctype
  push_text doctype if doctype
end

def compile_filter

def compile_filter
  unless filter = Filters.defined[@node.value[:name]]
    raise Error.new("Filter \"#{@node.value[:name]}\" is not defined.", @node.line - 1)
  end
  filter.internal_compile(self, @node.value[:text])
end

def compile_haml_comment; end

def compile_haml_comment; end

def compile_plain

def compile_plain
  push_text @node.value[:text]
end

def compile_root

def compile_root
  @dont_indent_next_line = @dont_tab_up_next_text = false
  @output_line = 1
  @indentation = nil
  yield
  flush_merged_text
end

def compile_script(&block)

def compile_script(&block)
  push_script(@node.value[:text],
    :preserve_script => @node.value[:preserve],
    :escape_html => @node.value[:escape_html], &block)
end

def compile_silent_script

def compile_silent_script
  return if @options[:suppress_eval]
  push_silent(@node.value[:text])
  keyword = @node.value[:keyword]
  ruby_block = block_given? && !keyword
  if block_given?
    # Store these values because for conditional statements,
    # we want to restore them for each branch
    @node.value[:dont_indent_next_line] = @dont_indent_next_line
    @node.value[:dont_tab_up_next_text] = @dont_tab_up_next_text
    yield
    push_silent("end", :can_suppress) unless @node.value[:dont_push_end]
  elsif keyword == "end"
    if @node.parent.children.last.equal?(@node)
      # Since this "end" is ending the block,
      # we don't need to generate an additional one
      @node.parent.value[:dont_push_end] = true
    end
    # Don't restore dont_* for end because it isn't a conditional branch.
  elsif Parser::MID_BLOCK_KEYWORDS.include?(keyword)
    # Restore dont_* for this conditional branch
    @dont_indent_next_line = @node.parent.value[:dont_indent_next_line]
    @dont_tab_up_next_text = @node.parent.value[:dont_tab_up_next_text]
  end
end

def compile_silent_script_with_haml_block_deprecation(&block)

def compile_silent_script_with_haml_block_deprecation(&block)
  unless block && !@node.value[:keyword] &&
      @node.value[:text] =~ ActionView::Template::Handlers::Erubis::BLOCK_EXPR
    return compile_silent_script_without_haml_block_deprecation(&block)
  end
  @node.value[:text] = "_hamlout.append_if_string= #{@node.value[:text]}"
  compile_silent_script_without_haml_block_deprecation(&block)
end

def compile_tag

def compile_tag
  t = @node.value
  # Get rid of whitespace outside of the tag if we need to
  rstrip_buffer! if t[:nuke_outer_whitespace]
  dont_indent_next_line =
    (t[:nuke_outer_whitespace] && !block_given?) ||
    (t[:nuke_inner_whitespace] && block_given?)
  if @options[:suppress_eval]
    object_ref = "nil"
    parse = false
    value = t[:parse] ? nil : t[:value]
    attributes_hashes = {}
    preserve_script = false
  else
    object_ref = t[:object_ref]
    parse = t[:parse]
    value = t[:value]
    attributes_hashes = t[:attributes_hashes]
    preserve_script = t[:preserve_script]
  end
  # Check if we can render the tag directly to text and not process it in the buffer
  if object_ref == "nil" && attributes_hashes.empty? && !preserve_script
    tag_closed = !block_given? && !t[:self_closing] && !parse
    open_tag = prerender_tag(t[:name], t[:self_closing], t[:attributes])
    if tag_closed
      open_tag << "#{value}</#{t[:name]}>"
      open_tag << "\n" unless t[:nuke_outer_whitespace]
    elsif !(parse || t[:nuke_inner_whitespace] ||
        (t[:self_closing] && t[:nuke_outer_whitespace]))
      open_tag << "\n"
    end
    push_merged_text(open_tag,
      tag_closed || t[:self_closing] || t[:nuke_inner_whitespace] ? 0 : 1,
      !t[:nuke_outer_whitespace])
    @dont_indent_next_line = dont_indent_next_line
    return if tag_closed
  else
    if attributes_hashes.empty?
      attributes_hashes = ''
    elsif attributes_hashes.size == 1
      attributes_hashes = ", #{attributes_hashes.first}"
    else
      attributes_hashes = ", (#{attributes_hashes.join(").merge(")})"
    end
    push_merged_text "<#{t[:name]}", 0, !t[:nuke_outer_whitespace]
    push_generated_script(
      "_hamlout.attributes(#{inspect_obj(t[:attributes])}, #{object_ref}#{attributes_hashes})")
    concat_merged_text(
      if t[:self_closing] && xhtml?
        " />" + (t[:nuke_outer_whitespace] ? "" : "\n")
      else
        ">" + ((if t[:self_closing] && html?
                  t[:nuke_outer_whitespace]
                else
                  !block_given? || t[:preserve_tag] || t[:nuke_inner_whitespace]
                end) ? "" : "\n")
      end)
    if value && !parse
      concat_merged_text("#{value}</#{t[:name]}>#{t[:nuke_outer_whitespace] ? "" : "\n"}")
    elsif !t[:nuke_inner_whitespace] && !t[:self_closing]
      @to_merge << [:text, '', 1]
    end
    @dont_indent_next_line = dont_indent_next_line
  end
  return if t[:self_closing]
  if value.nil?
    @output_tabs += 1 unless t[:nuke_inner_whitespace]
    yield if block_given?
    @output_tabs -= 1 unless t[:nuke_inner_whitespace]
    rstrip_buffer! if t[:nuke_inner_whitespace]
    push_merged_text("</#{t[:name]}>" + (t[:nuke_outer_whitespace] ? "" : "\n"),
      t[:nuke_inner_whitespace] ? 0 : -1, !t[:nuke_inner_whitespace])
    @dont_indent_next_line = t[:nuke_outer_whitespace]
    return
  end
  if parse
    push_script(value, t.merge(:in_tag => true))
    concat_merged_text("</#{t[:name]}>" + (t[:nuke_outer_whitespace] ? "" : "\n"))
  end
end

def concat_merged_text(text)

Concatenate `text` to `@buffer` without tabulation.
def concat_merged_text(text)
  @to_merge << [:text, text, 0]
end

def flush_merged_text

def flush_merged_text
  return if @to_merge.empty?
  str = ""
  mtabs = 0
  @to_merge.each do |type, val, tabs|
    case type
    when :text
      str << inspect_obj(val)[1...-1]
      mtabs += tabs
    when :script
      if mtabs != 0 && !@options[:ugly]
        val = "_hamlout.adjust_tabs(#{mtabs}); " + val
      end
      str << "\#{#{val}}"
      mtabs = 0
    else
      raise SyntaxError.new("[HAML BUG] Undefined entry in Haml::Compiler@to_merge.")
    end
  end
  unless str.empty?
    @precompiled <<
      if @options[:ugly]
        "_hamlout.buffer << \"#{str}\";"
      else
        "_hamlout.push_text(\"#{str}\", #{mtabs}, #{@dont_tab_up_next_text.inspect});"
      end
  end
  @to_merge = []
  @dont_tab_up_next_text = false
end

def locals_code(names)

def locals_code(names)
  names = names.keys if Hash == names
  names.map do |name|
    # Can't use || because someone might explicitly pass in false with a symbol
    sym_local = "_haml_locals[#{inspect_obj(name.to_sym)}]"
    str_local = "_haml_locals[#{inspect_obj(name.to_s)}]"
    "#{name} = #{sym_local}.nil? ? #{str_local} : #{sym_local}"
  end.join(';') + ';'
end

def precompiled_method_return_value

This method exists so it can be monkeypatched to return modified values.
Returns the string used as the return value of the precompiled method.
def precompiled_method_return_value
  "_erbout"
end

def precompiled_with_ambles(local_names)

Returns the precompiled string with the preamble and postamble
def precompiled_with_ambles(local_names)
  preamble = <<END.gsub("\n", ";")
n
nd Haml::Helpers
lout = @haml_buffer = Haml::Buffer.new(@haml_buffer, #{options_for_buffer.inspect})
out = _hamlout.buffer
_erb_template = true
  postamble = <<END.gsub("\n", ";")
ecompiled_method_return_value}
re
l_buffer = @haml_buffer.upper if @haml_buffer
  preamble + locals_code(local_names) + precompiled + postamble
end

def prerender_tag(name, self_close, attributes)

def prerender_tag(name, self_close, attributes)
  attributes_string = Compiler.build_attributes(
    html?, @options[:attr_wrapper], @options[:escape_attrs], attributes)
  "<#{name}#{attributes_string}#{self_close && xhtml? ? ' /' : ''}>"
end

def push_generated_script(text)

def push_generated_script(text)
  @to_merge << [:script, resolve_newlines + text]
  @output_line += text.count("\n")
end

def push_merged_text(text, tab_change = 0, indent = true)

without parsing it.
Adds `text` to `@buffer` with appropriate tabulation
def push_merged_text(text, tab_change = 0, indent = true)
  text = !indent || @dont_indent_next_line || @options[:ugly] ? text : "#{'  ' * @output_tabs}#{text}"
  @to_merge << [:text, text, tab_change]
  @dont_indent_next_line = false
end

def push_script(text, opts = {})

the result before it is added to `@buffer`
If `opts[:preserve_script]` is true, Haml::Helpers#find_and_flatten is run on

the scope object and the result to be added to `@buffer`.
Causes `text` to be evaluated in the context of
def push_script(text, opts = {})
  return if options[:suppress_eval]
  args = %w[preserve_script in_tag preserve_tag escape_html nuke_inner_whitespace]
  args.map! {|name| opts[name.to_sym]}
  args << !block_given? << @options[:ugly]
  no_format = @options[:ugly] &&
    !(opts[:preserve_script] || opts[:preserve_tag] || opts[:escape_html])
  output_expr = "(#{text}\n)"
  static_method = "_hamlout.#{static_method_name(:format_script, *args)}"
  # Prerender tabulation unless we're in a tag
  push_merged_text '' unless opts[:in_tag]
  unless block_given?
    push_generated_script(no_format ? "#{text}\n" : "#{static_method}(#{output_expr});")
    concat_merged_text("\n") unless opts[:in_tag] || opts[:nuke_inner_whitespace]
    return
  end
  flush_merged_text
  push_silent "haml_temp = #{text}"
  yield
  push_silent('end', :can_suppress) unless @node.value[:dont_push_end]
  @precompiled << "_hamlout.buffer << #{no_format ? "haml_temp.to_s;" : "#{static_method}(haml_temp);"}"
  concat_merged_text("\n") unless opts[:in_tag] || opts[:nuke_inner_whitespace] || @options[:ugly]
end

def push_silent(text, can_suppress = false)

does not output the result.
Evaluates `text` in the context of the scope object, but
def push_silent(text, can_suppress = false)
  flush_merged_text
  return if can_suppress && options[:suppress_eval]
  @precompiled << "#{resolve_newlines}#{text}\n"
  @output_line += text.count("\n") + 1
end

def push_text(text, tab_change = 0)

def push_text(text, tab_change = 0)
  push_merged_text("#{text}\n", tab_change)
end

def resolve_newlines

def resolve_newlines
  diff = @node.line - @output_line
  return "" if diff <= 0
  @output_line = @node.line
  "\n" * [diff, 0].max
end

def rstrip_buffer!(index = -1)

or the merged text
Get rid of and whitespace at the end of the buffer
def rstrip_buffer!(index = -1)
  last = @to_merge[index]
  if last.nil?
    push_silent("_hamlout.rstrip!", false)
    @dont_tab_up_next_text = true
    return
  end
  case last.first
  when :text
    last[1].rstrip!
    if last[1].empty?
      @to_merge.slice! index
      rstrip_buffer! index
    end
  when :script
    last[1].gsub!(/\(haml_temp, (.*?)\);$/, '(haml_temp.rstrip, \1);')
    rstrip_buffer! index - 1
  else
    raise SyntaxError.new("[HAML BUG] Undefined entry in Haml::Compiler@to_merge.")
  end
end

def text_for_doctype

def text_for_doctype
  if @node.value[:type] == "xml"
    return nil if html?
    wrapper = @options[:attr_wrapper]
    return "<?xml version=#{wrapper}1.0#{wrapper} encoding=#{wrapper}#{@node.value[:encoding] || "utf-8"}#{wrapper} ?>"
  end
  if html5?
    '<!DOCTYPE html>'
  else
    if xhtml?
      if @node.value[:version] == "1.1"
        '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">'
      elsif @node.value[:version] == "5"
        '<!DOCTYPE html>'
      else
        case @node.value[:type]
        when "strict";   '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">'
        when "frameset"; '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">'
        when "mobile";   '<!DOCTYPE html PUBLIC "-//WAPFORUM//DTD XHTML Mobile 1.2//EN" "http://www.openmobilealliance.org/tech/DTD/xhtml-mobile12.dtd">'
        when "rdfa";     '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd">'
        when "basic";    '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.1//EN" "http://www.w3.org/TR/xhtml-basic/xhtml-basic11.dtd">'
        else             '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">'
        end
      end
    elsif html4?
      case @node.value[:type]
      when "strict";   '<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">'
      when "frameset"; '<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN" "http://www.w3.org/TR/html4/frameset.dtd">'
      else             '<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">'
      end
    end
  end
end