import "dotenv/config";
import express from "express";
import cors from "cors";
import path from "path";
import { fileURLToPath } from "url";
import { ensureTenant } from "./src/db/repo.js";
import { addSseClient, removeSseClient } from "./src/services/sse.js";
import { makeGetConversations } from "./src/controllers/conversations.js";
import { makeListRuns, makeGetRunById } from "./src/controllers/runs.js";
import { makeSimSend } from "./src/controllers/sim.js";
import { makeEvolutionWebhook } from "./src/controllers/evolution.js";
import { makeGetConversationState } from "./src/controllers/conversationState.js";
import { makeListMessages } from "./src/controllers/messages.js";
import { makeSearchProducts } from "./src/controllers/products.js";
import { makeDeleteConversation, makeDeleteUser, makeListUsers, makeRetryLast } from "./src/controllers/admin.js";

async function configureUndiciDispatcher() {
  // Node 18+ usa undici debajo de fetch. Esto suele arreglar timeouts “fantasma” por keep-alive/pooling.
  // Nota: si el módulo `undici` no está disponible, no rompemos el arranque (solo logueamos warning).
  try {
    const { setGlobalDispatcher, Agent } = await import("undici");
    setGlobalDispatcher(
      new Agent({
        connections: 10,
        pipelining: 0,
        keepAliveTimeout: 10_000,
        keepAliveMaxTimeout: 10_000,
      })
    );
    console.log("[http] undici global dispatcher configured");
  } catch (e) {
    console.warn("[http] undici dispatcher not configured:", e?.message || e);
  }
}

const app = express();
app.use(cors());
app.use(express.json({ limit: "1mb" }));

// Serve /public as static (UI + webcomponents)
const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);
const publicDir = path.join(__dirname, "public");
app.use(express.static(publicDir));

/**
 * --- Tenant ---
 */
const TENANT_KEY = process.env.TENANT_KEY || "piaf";
let TENANT_ID = null;

function nowIso() {
  return new Date().toISOString();
}

/**
 * --- SSE endpoint ---
 */
app.get("/stream", (req, res) => {
  res.setHeader("Content-Type", "text/event-stream");
  res.setHeader("Cache-Control", "no-cache");
  res.setHeader("Connection", "keep-alive");
  res.flushHeaders?.();

  res.write(`event: hello\ndata: ${JSON.stringify({ ts: nowIso() })}\n\n`);
  addSseClient(res);

  req.on("close", () => {
    removeSseClient(res);
    res.end();
  });
});

/**
 * --- UI data endpoints ---
 */
app.post("/sim/send", makeSimSend());

app.get("/conversations", makeGetConversations(() => TENANT_ID));
app.get("/conversations/state", makeGetConversationState(() => TENANT_ID));
app.delete("/conversations/:chat_id", makeDeleteConversation(() => TENANT_ID));
app.post("/conversations/:chat_id/retry-last", makeRetryLast(() => TENANT_ID));
app.get("/messages", makeListMessages(() => TENANT_ID));
app.get("/products", makeSearchProducts(() => TENANT_ID));
app.get("/users", makeListUsers(() => TENANT_ID));
app.delete("/users/:chat_id", makeDeleteUser(() => TENANT_ID));

app.get("/runs", makeListRuns(() => TENANT_ID));

app.get("/runs/:run_id", makeGetRunById(() => TENANT_ID));

app.post("/webhook/evolution", makeEvolutionWebhook());

app.get("/", (req, res) => {
  res.sendFile(path.join(publicDir, "index.html"));
});

/**
 * --- Boot ---
 */
const port = process.env.PORT || 3000;

(async function boot() {
  await configureUndiciDispatcher();
  TENANT_ID = await ensureTenant({ key: TENANT_KEY, name: TENANT_KEY.toUpperCase() });
  app.listen(port, () => console.log(`UI: http://localhost:${port} (tenant=${TENANT_KEY})`));
})().catch((err) => {
  console.error("Boot failed:", err);
  process.exit(1);
});