add support for tool call (function call)

src/chatgpt.ts

@@ -12,6 +12,11 @@ export interface Message {
   role: "system" | "user" | "assistant" | "function";
   content: string | MessageDetail[];
   name?: "example_user" | "example_assistant";
+  tool_calls?: {
+    id: string;
+    type: string;
+    function: any;
+  }[];
 }
 export const getMessageText = (message: Message): string => {
   if (typeof message.content === "string") {
@@ -78,6 +83,7 @@ class Chat {
   OPENAI_API_KEY: string;
   messages: Message[];
   sysMessageContent: string;
+  toolsString: string;
   total_tokens: number;
   max_tokens: number;
   max_gen_tokens: number;
@@ -96,6 +102,7 @@ class Chat {
     OPENAI_API_KEY: string | undefined,
     {
       systemMessage = "",
+      toolsString = "",
       max_tokens = 4096,
       max_gen_tokens = 2048,
       enable_max_gen_tokens = true,
@@ -121,6 +128,7 @@ class Chat {
     this.enable_max_gen_tokens = enable_max_gen_tokens;
     this.tokens_margin = tokens_margin;
     this.sysMessageContent = systemMessage;
+    this.toolsString = toolsString;
     this.apiEndpoint = apiEndPoint;
     this.model = model;
     this.temperature = temperature;
@@ -178,6 +186,25 @@ class Chat {
       body["max_tokens"] = this.max_gen_tokens;
     }
 
+    // parse toolsString to function call format
+    const ts = this.toolsString.trim();
+    if (ts) {
+      try {
+        const fcList: any[] = JSON.parse(ts);
+        body["tools"] = fcList.map((fc) => {
+          return {
+            type: "function",
+            function: fc,
+          };
+        });
+      } catch (e) {
+        console.log("toolsString parse error");
+        throw (
+          "Function call toolsString parse error, not a valied json list: " + e
+        );
+      }
+    }
+
     return fetch(this.apiEndpoint, {
       method: "POST",
       headers: {
@@ -234,7 +261,7 @@ class Chat {
     }
   }
 
-  processFetchResponse(resp: FetchResponse): string {
+  processFetchResponse(resp: FetchResponse): Message {
     if (resp.error !== undefined) {
       throw JSON.stringify(resp.error);
     }
@@ -249,15 +276,19 @@ class Chat {
       this.forgetSomeMessages();
     }
 
-    return (
-      (resp?.choices[0]?.message?.content as string) ??
-      `Error: ${JSON.stringify(resp)}`
-    );
-  }
+    let content = "";
+    if (
+      !resp.choices[0]?.message?.content &&
+      !resp.choices[0]?.message?.tool_calls
+    ) {
+      content = `Unparsed response: ${JSON.stringify(resp)}`;
+    }
 
-  async complete(): Promise<string> {
-    const resp = await this.fetch();
-    return this.processFetchResponse(resp);
+    return {
+      role: "assistant",
+      content,
+      tool_calls: resp?.choices[0]?.message?.tool_calls,
+    };
   }
 
   completeWithSteam() {