feat: support multiple system message

src/chatgpt-api.ts

@@ -19,7 +19,7 @@ export class ChatGPTAPI {
   protected _apiOrg?: string
   protected _debug: boolean
 
-  protected _systemMessage: string
+  protected _systemMessage: string | string[]
   protected _completionParams: Omit<
     types.openai.CreateChatCompletionRequest,
     'messages' | 'n'
@@ -368,13 +368,22 @@ export class ChatGPTAPI {
     const maxNumTokens = this._maxModelTokens - this._maxResponseTokens
     let messages: types.openai.ChatCompletionRequestMessage[] = []
 
-    if (systemMessage) {
+    if (typeof systemMessage === 'string') {
       messages.push({
         role: 'system',
         content: systemMessage
       })
     }
 
+    if (Array.isArray(systemMessage)) {
+      messages = messages.concat(
+        systemMessage.map((content) => ({
+          role: 'system',
+          content
+        }))
+      )
+    }
+
     const systemMessageOffset = messages.length
     let nextMessages = text
       ? messages.concat([

src/types.ts

@@ -19,7 +19,7 @@ export type ChatGPTAPIOptions = {
     Omit<openai.CreateChatCompletionRequest, 'messages' | 'n' | 'stream'>
   >
 
-  systemMessage?: string
+  systemMessage?: string | string[]
 
   /** @defaultValue `4096` **/
   maxModelTokens?: number
@@ -41,7 +41,7 @@ export type SendMessageOptions = {
   conversationId?: string
   messageId?: string
   stream?: boolean
-  systemMessage?: string
+  systemMessage?: string | string[]
   timeoutMs?: number
   onProgress?: (partialResponse: ChatMessage) => void
   abortSignal?: AbortSignal