// simpleArgApply is used when no formatting template string is given.
func simpleArgApply(field *pb.Field, arg *pb.Argument) error {
switch val := arg.GetValue().(type) {
case *pb.Argument_Number:
field.Value = &pb.Field_Number{Number: val.Number}
case *pb.Argument_Str:
field.Value = &pb.Field_Str{Str: val.Str}
case *pb.Argument_Boolean:
field.Value = &pb.Field_Boolean{Boolean: val.Boolean}
default:
field.Value = nil
}
return nil
}
// ApplyArguments takes the given arguments and uses them to satisfy a field parameter. If a single argument and no
// formatting pattern are given the single argument is used as the field value. Otherwise the arguments will be used as
// arguments to Printf with the formatting string as the pattern.
func ApplyArguments(field *pb.Field, args ...*pb.Argument) error {
if field == nil {
return errors.New("field was nil")
} else if field.GetParam() == nil {
return fmt.Errorf("field %s does not have a parameter", field.Key)
} else if len(args) < 1 && field.GetParam().GetDefault() == nil {
return errors.New("an argument must be specified if no default is given")
} else if len(args) < 1 {
return applyDefault(field)
} else if len(args) == 1 && len(field.GetParam().Pattern) == 0 {
return simpleArgApply(field, args[0])
} else if len(args) > 1 && len(field.GetParam().Pattern) == 0 {
return errors.New("may only use multiple arguments if a string template is provided")
}
argVals := make([]interface{}, len(args))
for i, v := range args {
switch val := v.GetValue().(type) {
case *pb.Argument_Number:
argVals[i] = val.Number
case *pb.Argument_Str:
argVals[i] = val.Str
case *pb.Argument_Boolean:
argVals[i] = val.Boolean
}
}
val := fmt.Sprintf(field.GetParam().Pattern, argVals...)
field.Value = &pb.Field_Str{Str: val}
return nil
}
func applyDefault(field *pb.Field) error {
if field == nil {
return errors.New("field cannot be nil")
} else if field.GetParam() == nil {
return errors.New("field does not have parameters")
} else if field.GetParam().GetDefault() == nil {
return errors.New("fields has paramaters but default was nil")
}
switch d := field.GetParam().GetDefault().GetValue().(type) {
case *pb.Argument_Number:
field.Value = &pb.Field_Number{Number: d.Number}
case *pb.Argument_Str:
field.Value = &pb.Field_Str{Str: d.Str}
case *pb.Argument_Boolean:
field.Value = &pb.Field_Boolean{Boolean: d.Boolean}
}
return nil
}
