module ServiceVariables

# File lib/service_variables.rb, line 25
def boolean_option(name, default: nil, failure_mode: @failure_mode)
  getter_method_name = "#{name}?".to_sym
  setter_method_name = "#{name}=".to_sym

  define_singleton_method getter_method_name do
    # Note that all values are stored in Redis as strings.
    value = get(name, failure_mode)
    value.nil? ? default : get(name, failure_mode) == 'true'
  end

  # Allow for `name` and `name?` accessors of boolean options.
  singleton_class.send(:alias_method, name, getter_method_name)

  define_singleton_method setter_method_name do |value|
    raise InvalidValueError, "Value isn't `true` or `false`" unless BOOLEAN_VALUES.include?(value)
    set(name, value.to_s)
  end
end

# File lib/service_variables.rb, line 16
def configure(redis_client:, redis_key: nil, failure_mode: :raise_exception)
  @service_variables_redis_client = redis_client
  @redis_key = redis_key

  raise InvalidValueError unless FAILURE_MODES.include?(failure_mode)
  @failure_mode = failure_mode
  @last_value_map = {}
end

# File lib/service_variables.rb, line 57
def float_option(name, default: nil, min: nil, max: nil, failure_mode: @failure_mode)
  define_singleton_method name do
    get(name, failure_mode)&.to_f || default
  end

  define_singleton_method "#{name}=" do |value|
    value = Float(value) # raises ArgumentError if non float value
    raise InvalidValueError, "Value too small. min = #{min.to_f}" if min && min > value
    raise InvalidValueError, "Value too large. max = #{max.to_f}" if max && max < value
    set(name, value&.to_s)
  end
end

# File lib/service_variables.rb, line 44
def integer_option(name, default: nil, min: nil, max: nil, failure_mode: @failure_mode)
  define_singleton_method name do
    get(name, failure_mode)&.to_i || default
  end

  define_singleton_method "#{name}=" do |value|
    value = Integer(value) # raises ArgumentError if non integer value
    raise InvalidValueError, "Value too small. min = #{min.to_i}" if min && min > value
    raise InvalidValueError, "Value too large. max = #{max.to_i}" if max && max < value
    set(name, value&.to_s)
  end
end

# File lib/service_variables.rb, line 70
def string_option(name, default: nil, enum: nil, failure_mode: @failure_mode)
  define_singleton_method name do
    get(name, failure_mode) || default
  end

  define_singleton_method "#{name}=" do |value|
    raise InvalidValueError, "Only #{enum} values are allowed." if enum && !enum.include?(value)
    set(name, value)
  end
end

# File lib/service_variables.rb, line 83
def get(key, failure_mode)
  redis.hget(redis_hash_key, key)
rescue Redis::BaseConnectionError => e
  raise e if failure_mode == :raise_exception
  # If Redis returns a nil, then the default value is used, so we do the same with :use_default
  return nil if failure_mode == :use_default
  return @last_value_map[key] if failure_mode == :use_last_value
  raise InvalidValueError unless FAILURE_MODES.include?(failure_mode)
end

# File lib/service_variables.rb, line 103
def redis
  return @service_variables_redis_client if @service_variables_redis_client.is_a?(Redis)
  raise NotConfiguredError, 'Redis client not given.'
end

# File lib/service_variables.rb, line 108
def redis_hash_key
  @redis_key.nil? ? DEFAULT_REDIS_KEY : "#{DEFAULT_REDIS_KEY}:#{@redis_key}"
end

# File lib/service_variables.rb, line 93
def set(key, value)
  if value.nil?
    redis.hdel(redis_hash_key, key)
  else
    redis.hset(redis_hash_key, key, value)
  end

  @last_value_map[key] = value
end