// Validate validates a config value against this rule.
func (b *BoolRule) Validate(cv ctypes.ConfigValue) error {
	// Check that type is correct
	if cv.Type() != "bool" {
		return wrongType(b.key, cv.Type(), "bool")
	}
	return nil
}

// getConfigItemValue returns value of configuration item
func getConfigItemValue(item ctypes.ConfigValue) (interface{}, error) {

	var value interface{}

	switch item.Type() {
	case "string":
		value = item.(ctypes.ConfigValueStr).Value
		break

	case "float":
		value = item.(ctypes.ConfigValueFloat).Value
		break

	case "integer":
		value = item.(ctypes.ConfigValueInt).Value
		break

	case "bool":
		value = item.(ctypes.ConfigValueBool).Value
		break

	default:
		return nil, fmt.Errorf("Unsupported type of configuration item, type=%v", item.Type())
	}

	return value, nil
}

// Validates a config value against this rule.
func (s *StringRule) Validate(cv ctypes.ConfigValue) error {
	// Check that type is correct
	if cv.Type() != "string" {
		return wrongType(s.key, cv.Type(), "string")
	}
	return nil
}

// Validate Validates a config value against this rule.
func (f *FloatRule) Validate(cv ctypes.ConfigValue) error {
	// Check that type is correct
	if cv.Type() != FloatType {
		return wrongType(f.key, cv.Type(), FloatType)
	}
	// Check minimum. Type should be safe now because of the check above.
	if f.minimum != nil && cv.(ctypes.ConfigValueFloat).Value < *f.minimum {
		return errors.New(fmt.Sprintf("value is under minimum (%s value %f < %f)", f.key, cv.(ctypes.ConfigValueFloat).Value, *f.minimum))
	}
	// Check maximum. Type should be safe now because of the check above.
	if f.maximum != nil && cv.(ctypes.ConfigValueFloat).Value > *f.maximum {
		return errors.New(fmt.Sprintf("value is over maximum (%s value %f > %f)", f.key, cv.(ctypes.ConfigValueFloat).Value, *f.maximum))
	}
	return nil
}

// Validate Validates a config value against this rule.
func (i *IntRule) Validate(cv ctypes.ConfigValue) error {
	// Check that type is correct
	// when unmarshalling JSON numbers are converted to floats which is the reason
	// we are checking for integer below.
	// http://golang.org/pkg/encoding/json/#Marshal
	if cv.Type() != "integer" && cv.Type() != "float" {
		return wrongType(i.key, cv.Type(), "integer")
	}
	// Check minimum. Type should be safe now because of the check above.
	if i.minimum != nil && cv.(ctypes.ConfigValueInt).Value < *i.minimum {
		return errors.New(fmt.Sprintf("value is under minimum (%s value %d < %d)", i.key, cv.(ctypes.ConfigValueInt).Value, *i.minimum))
	}
	// Check maximum. Type should be safe now because of the check above.
	if i.maximum != nil && cv.(ctypes.ConfigValueInt).Value > *i.maximum {
		return errors.New(fmt.Sprintf("value is over maximum (%s value %d > %d)", i.key, cv.(ctypes.ConfigValueInt).Value, *i.maximum))
	}
	return nil
}