# frozen_string_literal: true require ‘mail/utilities’ require ‘mail/parser_tools’

begin

original_verbose, $VERBOSE = $VERBOSE, nil

%%{

machine content_disposition;
alphtype int;

# Disposition Type
action disp_type_s { disp_type_s = p }
action disp_type_e { content_disposition.disposition_type = chars(data, disp_type_s, p-1).downcase }

# Parameter Attribute
action param_attr_s { param_attr_s = p }
action param_attr_e { param_attr = chars(data, param_attr_s, p-1) }

# Quoted String
action qstr_s { qstr_s = p }
action qstr_e { qstr = chars(data, qstr_s, p-1) }

# Parameter Value
action param_val_s { param_val_s = p }
action param_val_e {
  if param_attr.nil?
    raise Mail::Field::ParseError.new(Mail::ContentDispositionElement, data, "no attribute for value")
  end

  # Use quoted string value if one exists, otherwise use parameter value
  value = qstr || chars(data, param_val_s, p-1)

  content_disposition.parameters << { param_attr => value }
  param_attr = nil
  qstr = nil
}

# No-op actions
action comment_e { }
action comment_s { }
action phrase_e { }
action phrase_s { }
action main_type_e { }
action main_type_s { }
action sub_type_e { }
action sub_type_s { }

include rfc2183_content_disposition "rfc2183_content_disposition.rl";
main := disposition;

}%%

module Mail::Parsers

module ContentDispositionParser
  extend Mail::ParserTools

  ContentDispositionStruct = Struct.new(:disposition_type, :parameters, :error)

  %%write data noprefix;

  def self.parse(data)
    data = data.dup.force_encoding(Encoding::ASCII_8BIT) if data.respond_to?(:force_encoding)

    content_disposition = ContentDispositionStruct.new('', [])
    return content_disposition if Mail::Utilities.blank?(data)

    # Parser state
    disp_type_s = param_attr_s = param_attr = qstr_s = qstr = param_val_s = nil

    # 5.1 Variables Used by Ragel
    p = 0
    eof = pe = data.length
    stack = []

    %%write init;
    %%write exec;

    if p != eof || cs < %%{ write first_final; }%%
      raise Mail::Field::IncompleteParseError.new(Mail::ContentDispositionElement, data, p)
    end

    content_disposition
  end
end

end

ensure

$VERBOSE = original_verbose

end