class Rails::Generators::GeneratedAttribute

def column_name
  @column_name ||= reference? ? "#{name}_id" : name
end

def default
  @default ||= case type
    when :integer                     then 1
    when :float                       then 1.5
    when :decimal                     then "9.99"
    when :datetime, :timestamp, :time then Time.now.to_s(:db)
    when :date                        then Date.today.to_s(:db)
    when :string                      then name == "type" ? "" : "MyString"
    when :text                        then "MyText"
    when :boolean                     then false
    when :references, :belongs_to     then nil
    else
      ""
  end
end

def field_type
  @field_type ||= case type
    when :integer              then :number_field
    when :float, :decimal      then :text_field
    when :time                 then :time_select
    when :datetime, :timestamp then :datetime_select
    when :date                 then :date_select
    when :text                 then :text_area
    when :boolean              then :check_box
    else
      :text_field
  end
end

def foreign_key?
  !!(name =~ /_id$/)
end

def has_index?
  @has_index
end

def has_uniq_index?
  @has_uniq_index
end

def human_name
  name.humanize
end

def index_name
  @index_name ||= if polymorphic?
    %w(id type).map { |t| "#{name}_#{t}" }
  else
    column_name
  end
end

def initialize(name, type=nil, index_type=false, attr_options={})
  @name           = name
  @type           = type || :string
  @has_index      = INDEX_OPTIONS.include?(index_type)
  @has_uniq_index = UNIQ_INDEX_OPTIONS.include?(index_type)
  @attr_options   = attr_options
end

def inject_index_options
  has_uniq_index? ? ", unique: true" : ""
end

def inject_options
  "".tap { |s| options_for_migration.each { |k,v| s << ", #{k}: #{v.inspect}" } }
end

def options_for_migration
  @attr_options.dup.tap do |options|
    if required?
      options.delete(:required)
      options[:null] = false
    end
    if reference? && !polymorphic?
      options[:foreign_key] = true
    end
  end
end

def parse(column_definition)
  name, type, has_index = column_definition.split(':')
  # if user provided "name:index" instead of "name:string:index"
  # type should be set blank so GeneratedAttribute's constructor
  # could set it to :string
  has_index, type = type, nil if INDEX_OPTIONS.include?(type)
  type, attr_options = *parse_type_and_options(type)
  type = type.to_sym if type
  if type && reference?(type)
    if UNIQ_INDEX_OPTIONS.include?(has_index)
      attr_options[:index] = { unique: true }
    end
  end
  new(name, type, has_index, attr_options)
end

def parse_type_and_options(type)
  case type
  when /(string|text|binary|integer)\{(\d+)\}/
    return $1, limit: $2.to_i
  when /decimal\{(\d+)[,.-](\d+)\}/
    return :decimal, precision: $1.to_i, scale: $2.to_i
  when /(references|belongs_to)\{(.+)\}/
    type = $1
    provided_options = $2.split(/[,.-]/)
    options = Hash[provided_options.map { |opt| [opt.to_sym, true] }]
    return type, options
  else
    return type, {}
  end
end

def password_digest?
  name == 'password' && type == :digest
end

def plural_name
  name.sub(/_id$/, '').pluralize
end

def polymorphic?
  self.attr_options[:polymorphic]
end

def reference?(type)
  [:references, :belongs_to].include? type
end

def reference?
  self.class.reference?(type)
end

def required?
  self.attr_options[:required]
end

def singular_name
  name.sub(/_id$/, '').singularize
end

def token?
  type == :token
end