class SassC::ImportHandler

def import_function
  @import_function ||= FFI::Function.new(:pointer, [:string, :pointer, :pointer]) do |path, importer_entry, compiler|
    last_import = Native::compiler_get_last_import(compiler)
    parent_path = Native::import_get_abs_path(last_import)
    imports = [*@importer.imports(path, parent_path)]
    imports_to_native(imports)
  end
end

def imports_to_native(imports)
  import_list = Native.make_import_list(imports.size)
  imports.each_with_index do |import, i|
    source = import.source ? Native.native_string(import.source) : nil
    source_map_path = nil
    entry = Native.make_import_entry(import.path, source, source_map_path)
    Native.import_set_list_entry(import_list, i, entry)
  end
  import_list
end

def initialize(options)
  @importer = if options[:importer]
    options[:importer].new(options)
  else
    nil
  end
end

def setup(native_options)
  return unless @importer
  importer_callback = Native.make_importer(import_function, nil)
  list = Native.make_function_list(1)
  Native::function_set_list_entry(list, 0, importer_callback)
  Native.option_set_c_importers(native_options, list)
end