func()

in message.go [2091:2150]

• 54 lines of code
• 18 McCabe index (conditional complexity)

func (acc *Message) Accumulate(event MessageStreamEventUnion) error {
	if acc == nil {
		return fmt.Errorf("accumulate: cannot accumlate into nil Message")
	}

	switch event := event.AsAny().(type) {
	case MessageStartEvent:
		*acc = event.Message
	case MessageDeltaEvent:
		acc.StopReason = MessageStopReason(event.Delta.StopReason)
		acc.StopSequence = event.Delta.StopSequence
		acc.Usage.OutputTokens = event.Usage.OutputTokens

		// acc.JSON.StopReason = event.Delta.JSON.StopReason
		// acc.JSON.StopSequence = event.Delta.JSON.StopSequence
		// acc.Usage.JSON.OutputTokens = event.Usage.JSON.OutputTokens
	case MessageStopEvent:
		accJson, err := json.Marshal(acc)
		if err != nil {
			return fmt.Errorf("error converting content block to JSON: %w", err)
		}
		acc.JSON.raw = string(accJson)
	case ContentBlockStartEvent:
		acc.Content = append(acc.Content, ContentBlockUnion{})
		err := acc.Content[len(acc.Content)-1].UnmarshalJSON([]byte(event.ContentBlock.RawJSON()))
		if err != nil {
			return err
		}
	case ContentBlockDeltaEvent:
		if len(acc.Content) == 0 {
			return fmt.Errorf("received event of type %s but there was no content block", event.Type)
		}
		cb := &acc.Content[len(acc.Content)-1]
		switch delta := event.Delta.AsAny().(type) {
		case TextDelta:
			cb.Text += delta.Text
		case InputJSONDelta:
			if string(cb.Input) == "{}" {
				cb.Input = json.RawMessage{}
			}
			cb.Input = append(cb.Input, []byte(delta.PartialJSON)...)
		case ThinkingDelta:
			cb.Thinking += delta.Thinking
		case SignatureDelta:
			cb.Signature += delta.Signature
		}
	case ContentBlockStopEvent:
		if len(acc.Content) == 0 {
			return fmt.Errorf("received event of type %s but there was no content block", event.Type)
		}
		contentBlock := &acc.Content[len(acc.Content)-1]
		cbJson, err := json.Marshal(contentBlock)
		if err != nil {
			return fmt.Errorf("error converting content block to JSON: %w", err)
		}
		contentBlock.JSON.raw = string(cbJson)
	}

	return nil
}