Refactor OpenAI service to manage env and convo creation

- Add fromEnv factory to OpenAIService to handle env vars
- Move conversation creation into OpenAIService
- Update create- chat-conversation function to use new OpenAIService
  methods
- Add CORS headers to responses

supabase/functions/create-chat-conversation/index.ts

@@ -1,5 +1,7 @@
 // Setup type definitions for built-in Supabase Runtime APIs
 import "@supabase/functions-js/edge-runtime.d.ts";
+import { corsHeaders } from "../_shared/cors.ts";
+import { OpenAIService } from "../_shared/openai-service.ts";
 import { createClient } from "https://esm.sh/@supabase/supabase-js@2";
 
 type WebhookPayload = {
@@ -13,9 +15,6 @@ type WebhookPayload = {
 const SUPABASE_URL = Deno.env.get("SUPABASE_URL") ?? "";
 const SUPABASE_SERVICE_ROLE_KEY =
   Deno.env.get("SUPABASE_SERVICE_ROLE_KEY") ?? "";
-const OPENAI_API_KEY = Deno.env.get("OPENAI_API_KEY") ?? "";
-const OPENAI_BASE_URL =
-  Deno.env.get("OPENAI_BASE_URL") ?? "https://api.openai.com/v1";
 
 const ALLOWED_SCHEMA = "public";
 const ALLOWED_TABLES = new Set(["planes_estudio", "asignaturas"]);
@@ -27,27 +26,16 @@ const supabase = createClient(SUPABASE_URL, SUPABASE_SERVICE_ROLE_KEY, {
 function jsonResponse(status: number, body: Record<string, unknown>) {
   return new Response(JSON.stringify(body), {
     status,
-    headers: { "Content-Type": "application/json" },
+    headers: { "Content-Type": "application/json", ...corsHeaders },
   });
 }
 
-async function createConversationId(metadata: Record<string, string>) {
-  const response = await fetch(`${OPENAI_BASE_URL}/conversations`, {
-    method: "POST",
-    headers: {
-      "Content-Type": "application/json",
-      Authorization: `Bearer ${OPENAI_API_KEY}`,
-    },
-    body: JSON.stringify({ metadata }),
-  });
-
-  if (!response.ok) {
-    const errorText = await response.text();
-    throw new Error(`OpenAI error: ${response.status} ${errorText}`);
-  }
-
-  const data = await response.json();
-  const conversationId = data?.id as string | undefined;
+async function createConversationId(
+  openaiService: OpenAIService,
+  metadata: Record<string, string>,
+) {
+  const conversation = await openaiService.createConversation(metadata);
+  const conversationId = conversation?.id as string | undefined;
 
   if (!conversationId) {
     throw new Error("OpenAI response missing conversation id");
@@ -65,8 +53,9 @@ Deno.serve(async (req) => {
     return jsonResponse(500, { error: "Supabase env vars missing" });
   }
 
-  if (!OPENAI_API_KEY) {
-    return jsonResponse(500, { error: "OPENAI_API_KEY missing" });
+  const openaiService = OpenAIService.fromEnv();
+  if (!(openaiService instanceof OpenAIService)) {
+    return jsonResponse(500, { error: openaiService.message });
   }
 
   let payload: WebhookPayload;
@@ -108,7 +97,7 @@ Deno.serve(async (req) => {
 
   let conversationId: string;
   try {
-    conversationId = await createConversationId({
+    conversationId = await createConversationId(openaiService, {
       table,
       record_id: String(recordId),
     });