From 54ffb52838f55493e566dc4c109a2e10b3aee186 Mon Sep 17 00:00:00 2001
From: Luis Pater <webmaster@idotorg.org>
Date: Fri, 5 Sep 2025 09:02:24 +0800
Subject: [PATCH] Add `FunctionCallIndex` to `ConvertCliToOpenAIParams` and
 enhance tool call handling

- Introduced `FunctionCallIndex` to track and manage function call indices within `ConvertCliToOpenAIParams`.
- Enhanced handling for `response.completed` and `response.output_item.done` data types to support tool call scenarios.
- Improved logic for restoring original tool names and setting function arguments during response parsing.
---
 .../chat-completions/codex_openai_response.go | 47 ++++++++++++-------
 1 file changed, 29 insertions(+), 18 deletions(-)

diff --git a/internal/translator/codex/openai/chat-completions/codex_openai_response.go b/internal/translator/codex/openai/chat-completions/codex_openai_response.go
index 49ed00ef..9a596426 100644
--- a/internal/translator/codex/openai/chat-completions/codex_openai_response.go
+++ b/internal/translator/codex/openai/chat-completions/codex_openai_response.go
@@ -21,9 +21,10 @@ var (
 
 // ConvertCliToOpenAIParams holds parameters for response conversion.
 type ConvertCliToOpenAIParams struct {
-	ResponseID string
-	CreatedAt  int64
-	Model      string
+	ResponseID        string
+	CreatedAt         int64
+	Model             string
+	FunctionCallIndex int
 }
 
 // ConvertCodexResponseToOpenAI translates a single chunk of a streaming response from the
@@ -43,9 +44,10 @@ type ConvertCliToOpenAIParams struct {
 func ConvertCodexResponseToOpenAI(_ context.Context, modelName string, originalRequestRawJSON, requestRawJSON, rawJSON []byte, param *any) []string {
 	if *param == nil {
 		*param = &ConvertCliToOpenAIParams{
-			Model:      modelName,
-			CreatedAt:  0,
-			ResponseID: "",
+			Model:             modelName,
+			CreatedAt:         0,
+			ResponseID:        "",
+			FunctionCallIndex: -1,
 		}
 	}
 
@@ -108,27 +110,36 @@ func ConvertCodexResponseToOpenAI(_ context.Context, modelName string, originalR
 			template, _ = sjson.Set(template, "choices.0.delta.content", deltaResult.String())
 		}
 	} else if dataType == "response.completed" {
-		template, _ = sjson.Set(template, "choices.0.finish_reason", "stop")
-		template, _ = sjson.Set(template, "choices.0.native_finish_reason", "stop")
+		finishReason := "stop"
+		if (*param).(*ConvertCliToOpenAIParams).FunctionCallIndex != -1 {
+			finishReason = "tool_calls"
+		}
+		template, _ = sjson.Set(template, "choices.0.finish_reason", finishReason)
+		template, _ = sjson.Set(template, "choices.0.native_finish_reason", finishReason)
 	} else if dataType == "response.output_item.done" {
-		functionCallItemTemplate := `{"id": "","type": "function","function": {"name": "","arguments": ""}}`
+		functionCallItemTemplate := `{"index":0,"id":"","type":"function","function":{"name":"","arguments":""}}`
 		itemResult := rootResult.Get("item")
 		if itemResult.Exists() {
 			if itemResult.Get("type").String() != "function_call" {
 				return []string{}
 			}
+
+			// set the index
+			(*param).(*ConvertCliToOpenAIParams).FunctionCallIndex++
+			functionCallItemTemplate, _ = sjson.Set(functionCallItemTemplate, "index", (*param).(*ConvertCliToOpenAIParams).FunctionCallIndex)
+
 			template, _ = sjson.SetRaw(template, "choices.0.delta.tool_calls", `[]`)
 			functionCallItemTemplate, _ = sjson.Set(functionCallItemTemplate, "id", itemResult.Get("call_id").String())
-			{
-				// Restore original tool name if it was shortened
-				name := itemResult.Get("name").String()
-				// Build reverse map on demand from original request tools
-				rev := buildReverseMapFromOriginalOpenAI(originalRequestRawJSON)
-				if orig, ok := rev[name]; ok {
-					name = orig
-				}
-				functionCallItemTemplate, _ = sjson.Set(functionCallItemTemplate, "function.name", name)
+
+			// Restore original tool name if it was shortened
+			name := itemResult.Get("name").String()
+			// Build reverse map on demand from original request tools
+			rev := buildReverseMapFromOriginalOpenAI(originalRequestRawJSON)
+			if orig, ok := rev[name]; ok {
+				name = orig
 			}
+			functionCallItemTemplate, _ = sjson.Set(functionCallItemTemplate, "function.name", name)
+
 			functionCallItemTemplate, _ = sjson.Set(functionCallItemTemplate, "function.arguments", itemResult.Get("arguments").String())
 			template, _ = sjson.Set(template, "choices.0.delta.role", "assistant")
 			template, _ = sjson.SetRaw(template, "choices.0.delta.tool_calls.-1", functionCallItemTemplate)