Module: FlagShihTzu::ClassMethods

22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102

# File 'lib/flag_shih_tzu.rb', line 22

def has_flags(*args)
  flag_hash, opts = parse_options(*args)
  opts = {
    :named_scopes => true,
    :column => DEFAULT_COLUMN_NAME,
    :flag_query_mode => :in_list
  }.update(opts)
  colmn = opts[:column].to_s

  return unless check_flag_column(colmn)

  # options are stored in a class level hash and apply per-column
  self.flag_options ||= {}
  self.flag_options[colmn] = opts

  # the mappings are stored in this class level hash and apply per-column
  self.flag_mapping ||= {}
  self.flag_mapping[colmn] ||= {}

  flag_hash.each do |flag_key, flag_name|
    raise ArgumentError, "has_flags: flag keys should be positive integers, and #{flag_key} is not" unless is_valid_flag_key(flag_key)
    raise ArgumentError, "has_flags: flag names should be symbols, and #{flag_name} is not" unless is_valid_flag_name(flag_name)
    next if flag_mapping[colmn][flag_name] & (1 << (flag_key - 1)) # next if already methods defined by flagshitzu
    raise ArgumentError, "has_flags: flag name #{flag_name} already defined, please choose different name" if method_defined?(flag_name)

    flag_mapping[colmn][flag_name] = 1 << (flag_key - 1)

    class_eval <<-EVAL
      def #{flag_name}
        flag_enabled?(:#{flag_name}, '#{colmn}')
      end

      def #{flag_name}?
        flag_enabled?(:#{flag_name}, '#{colmn}')
      end

      def #{flag_name}=(value)
        FlagShihTzu::TRUE_VALUES.include?(value) ? enable_flag(:#{flag_name}, '#{colmn}') : disable_flag(:#{flag_name}, '#{colmn}')
      end

      def #{flag_name}_changed?
        if colmn_changes = changes['#{colmn}']
          flag_bit = self.class.flag_mapping['#{colmn}'][:#{flag_name}]
          (colmn_changes[0] & flag_bit) != (colmn_changes[1] & flag_bit)
        else
          false
        end
      end

      def self.#{flag_name}_condition(options = {})
        sql_condition_for_flag(:#{flag_name}, '#{colmn}', true, options[:table_alias] || self.table_name)
      end

      def self.not_#{flag_name}_condition
        sql_condition_for_flag(:#{flag_name}, '#{colmn}', false)
      end
    EVAL

    # Define bancg methods when requested
    if flag_options[colmn][:bang_methods]
      class_eval <<-EVAL
        def #{flag_name}!
          enable_flag(:#{flag_name}, '#{colmn}')
        end

        def not_#{flag_name}!
          disable_flag(:#{flag_name}, '#{colmn}')
        end
      EVAL
    end

    # Define the named scopes if the user wants them and AR supports it
    if flag_options[colmn][:named_scopes] && respond_to?(named_scope_method)
      class_eval <<-EVAL
        #{named_scope_method} :#{flag_name}, lambda { { :conditions => #{flag_name}_condition } }
        #{named_scope_method} :not_#{flag_name}, lambda { { :conditions => not_#{flag_name}_condition } }
      EVAL
    end
  end

end