module Nickserver; module HKP
  class ParseKeyInfo

    # for this regexp to work, the source text must end in a trailing "\n",
    # which the output of sks does.
    MATCH_PUB_KEY = /(^pub:.+?\n(^uid:.+?\n)+)/m

    #  header        -- header of the hkp response
    #  vindex_result -- raw output from a vindex hkp query (machine readable)
    def initialize(header, vindex_result)
      @header = header
      @vindex_result = vindex_result
    end

    def status(uid)
      if header.status == 200 && keys(uid).any?
        200
      else
        error_status(uid)
      end
    end

    def keys(uid)
      key_infos(uid).reject { |key| error_for_key(key) }
    end

    def msg(uid)
      if errors(uid).any?
        error_messages(uid).join "\n"
      else
        "Could not fetch keyinfo."
      end
    end

    protected

    attr_reader :header
    attr_reader :vindex_result

    def error_status(uid)
      if header.status != 200
        header.status
      else
        if errors(uid).any?
          500
        else
          404
        end
      end
    end

    def errors(uid)
      key_infos(uid).map{|key| error_for_key(key) }.compact
    end

    def error_messages(uid)
      key_infos(uid).map do |key|
        err = error_for_key(key)
        error_message(uid, key, err)
      end.compact
    end

    def key_infos(uid)
      all_key_infos.select do |key_info|
        key_info.uids.include?(uid)
      end
    end

    def all_key_infos
      @all_key_infos ||= vindex_result.scan(MATCH_PUB_KEY).map do |match|
        KeyInfo.new(match[0])
      end
    end

    def error_message(uid, key, err)
      "Ignoring key #{key.keyid} for #{uid}: #{err}" if err
    end

    def error_for_key(key)
      if key.keylen < 2048
        "key length is too short."
      elsif key.expired?
        "key expired."
      elsif key.revoked?
        "key revoked."
      elsif key.disabled?
        "key disabled."
      elsif key.expirationdate && key.expirationdate < Time.now
        "key expired"
      end
    end
  end
end; end