class Opal::Nodes::TopNode

def absolute_const
  @define_absolute_const = true
  '$$$'
end

def add_file_source_embed
  filename = compiler.file
  source = compiler.source
  unshift "Opal.file_sources[#{filename.to_json}] = #{source.to_json};\n"
end

def add_used_helpers
  compiler.helpers.to_a.reverse_each { |h| prepend_scope_temp "$#{h} = Opal.#{h}" }
end

def closing
  if compiler.requirable?
    line "};\n"
    if compiler.load?
      # Opal.load normalizes the path, so that we can't
      # require absolute paths from CLI. For other cases
      # we can expect the module names to be normalized
      # already.
      line "Opal.load_normalized(#{module_name});"
    end
  elsif compiler.eval?
    line "})(Opal, self);"
  else
    line "});\n"
  end
end

def compile
  compiler.top_scope = self
  compiler.dynamic_cache_result = true if sexp.meta[:dynamic_cache_result]
  push version_comment
  helper :return_val if compiler.eof_content
  if body == s(:nil)
    # A shortpath for empty (stub?) modules.
    if compiler.requirable? || compiler.esm? || compiler.eval?
      unshift 'Opal.return_val(Opal.nil); '
      definition
    else
      unshift 'Opal.nil; '
    end
  else
    in_scope do
      line '"use strict";' if compiler.use_strict?
      body_code = in_closure(Closure::JS_FUNCTION | Closure::TOP) do
        stmt(stmts)
      end
      body_code = [body_code] unless body_code.is_a?(Array)
      if compiler.eval?
        add_temp '$nesting = self.$$is_a_module ? [self] : [self.$$class]' if @define_nesting
      else
        add_temp 'self = Opal.top' if @define_self
        add_temp '$nesting = []' if @define_nesting
      end
      add_temp '$$ = Opal.$r($nesting)' if @define_relative_access
      add_temp 'nil = Opal.nil'
      add_temp '$$$ = Opal.$$$' if @define_absolute_const
      add_used_helpers
      line scope.to_vars
      compile_method_stubs
      compile_irb_vars
      compile_end_construct
      line body_code
    end
    opening
    definition
    closing
  end
  add_file_source_embed if compiler.enable_file_source_embed?
end

def compile_end_construct
  if content = compiler.eof_content
    line 'var $__END__ = Opal.Object.$new();'
    line "$__END__.$read = $return_val(#{content.inspect});"
  end
end

def compile_irb_vars
  if compiler.irb?
    line 'if (!Opal.irb_vars) { Opal.irb_vars = {}; }'
  end
end

def compile_method_stubs
  if compiler.method_missing?
    calls = compiler.method_calls
    stubs = calls.to_a.map(&:to_s).join(',')
    line "Opal.add_stubs('#{stubs}');" unless stubs.empty?
  end
end

def definition
  if compiler.requirable?
    unshift "Opal.modules[#{module_name}] = "
  elsif compiler.esm? && !compiler.no_export?
    unshift 'export default '
  end
end

def module_name
  Opal::Compiler.module_name(compiler.file).inspect
end

def opening
  async_prefix = "async " if await_encountered
  if compiler.requirable?
    unshift "#{async_prefix}function(Opal) {"
  elsif compiler.eval?
    unshift "(#{async_prefix}function(Opal, self) {"
  else
    unshift "Opal.queue(#{async_prefix}function(Opal) {"
  end
end

def stmts
  compiler.returns(body)
end

def version_comment
  "/* Generated by Opal #{Opal::VERSION} */"
end