ds2api/internal/format/openai/render_responses.go

package openai

import (
	"encoding/json"
	"strings"
	"time"

	"github.com/google/uuid"

	"ds2api/internal/util"
)

func BuildResponseObject(responseID, model, finalPrompt, finalThinking, finalText string, toolNames []string) map[string]any {
	// Align responses tool-call semantics with chat/completions:
	// mixed prose + tool_call payloads should still be interpreted as tool calls.
	detected := util.ParseToolCalls(finalText, toolNames)
	if len(detected) == 0 && strings.TrimSpace(finalThinking) != "" {
		detected = util.ParseToolCalls(finalThinking, toolNames)
	}
	exposedOutputText := finalText
	output := make([]any, 0, 2)
	if len(detected) > 0 {
		exposedOutputText = ""
		if strings.TrimSpace(finalThinking) != "" {
			output = append(output, map[string]any{
				"type": "reasoning",
				"text": finalThinking,
			})
		}
		formatted := util.FormatOpenAIToolCalls(detected)
		output = append(output, toResponsesFunctionCallItems(formatted)...)
		output = append(output, map[string]any{
			"type":       "tool_calls",
			"tool_calls": formatted,
		})
	} else {
		content := make([]any, 0, 2)
		if finalThinking != "" {
			content = append([]any{map[string]any{
				"type": "reasoning",
				"text": finalThinking,
			}}, content...)
		}
		if strings.TrimSpace(finalText) != "" {
			content = append(content, map[string]any{
				"type": "output_text",
				"text": finalText,
			})
		}
		if strings.TrimSpace(finalText) == "" && strings.TrimSpace(finalThinking) != "" {
			exposedOutputText = finalThinking
		}
		output = append(output, map[string]any{
			"type":    "message",
			"id":      "msg_" + strings.ReplaceAll(uuid.NewString(), "-", ""),
			"role":    "assistant",
			"content": content,
		})
	}
	return map[string]any{
		"id":          responseID,
		"type":        "response",
		"object":      "response",
		"created_at":  time.Now().Unix(),
		"status":      "completed",
		"model":       model,
		"output":      output,
		"output_text": exposedOutputText,
		"usage":       BuildResponsesUsage(finalPrompt, finalThinking, finalText),
	}
}

func toResponsesFunctionCallItems(toolCalls []map[string]any) []any {
	if len(toolCalls) == 0 {
		return nil
	}
	out := make([]any, 0, len(toolCalls))
	for _, tc := range toolCalls {
		callID, _ := tc["id"].(string)
		if strings.TrimSpace(callID) == "" {
			callID = "call_" + strings.ReplaceAll(uuid.NewString(), "-", "")
		}
		name := ""
		args := "{}"
		if fn, ok := tc["function"].(map[string]any); ok {
			if n, _ := fn["name"].(string); strings.TrimSpace(n) != "" {
				name = n
			}
			if a, _ := fn["arguments"].(string); strings.TrimSpace(a) != "" {
				args = a
			}
		}
		out = append(out, map[string]any{
			"id":        "fc_" + strings.ReplaceAll(uuid.NewString(), "-", ""),
			"type":      "function_call",
			"call_id":   callID,
			"name":      name,
			"arguments": normalizeJSONString(args),
			"status":    "completed",
		})
	}
	return out
}

func normalizeJSONString(raw string) string {
	s := strings.TrimSpace(raw)
	if s == "" {
		return "{}"
	}
	var v any
	if err := json.Unmarshal([]byte(s), &v); err != nil {
		return raw
	}
	b, err := json.Marshal(v)
	if err != nil {
		return raw
	}
	return string(b)
}