import dotenv from "dotenv";
dotenv.config();

import express, { Request, Response, NextFunction } from "express";
import cookieParser from "cookie-parser";
import crypto from "crypto";
import path from "path";
import fs from "fs/promises";

import { parseNovavps, getValidConnections } from "./novavps";
import { parseXrayPanel, syncNovavpsToXray } from "./xray-panel";
import { closeBrowser } from "./browser";
import {
  loadConfig,
  saveConfig,
  loadState,
  saveState,
  resetState,
  AppState,
} from "./data-store";

const app = express();
const PORT = parseInt(process.env.PORT || "3000", 10);

const SESSION_SECRET = process.env.SESSION_SECRET || crypto.randomBytes(32).toString("hex");
const SESSION_TTL = 60 * 60 * 1000;

const sessions = new Map<string, { createdAt: number; lastAccess: number }>();

app.use(express.json({ limit: "1mb" }));
app.use(cookieParser());
app.use(express.static(path.resolve(__dirname, "..", "public")));

interface PanelConfig {
  url: string;
  username: string;
  password: string;
  label: string;
}

function getPanels(): PanelConfig[] {
  const panels: PanelConfig[] = [];
  const url1 = process.env.XRAY_URL;
  const user1 = process.env.XRAY_USERNAME;
  const pass1 = process.env.XRAY_PASSWORD;
  if (url1 && user1 && pass1) {
    panels.push({ url: url1, username: user1, password: pass1, label: "xray1" });
  }
  const url2 = process.env.XRAY_URL2;
  const user2 = process.env.XRAY_USERNAME2;
  const pass2 = process.env.XRAY_PASSWORD2;
  if (url2 && user2 && pass2) {
    panels.push({ url: url2, username: user2, password: pass2, label: "xray2" });
  }
  return panels;
}

function validCredentials(username: string, password: string): boolean {
  const panels = getPanels();
  return panels.some(
    (p) => p.username === username && p.password === password
  );
}

function createSession(): string {
  const token = crypto.randomBytes(32).toString("hex");
  const now = Date.now();
  sessions.set(token, { createdAt: now, lastAccess: now });
  return token;
}

function getSession(token: string | undefined): { createdAt: number; lastAccess: number } | null {
  if (!token) return null;
  const session = sessions.get(token);
  if (!session) return null;
  if (Date.now() - session.lastAccess > SESSION_TTL) {
    sessions.delete(token);
    return null;
  }
  session.lastAccess = Date.now();
  return session;
}

function authMiddleware(req: Request, res: Response, next: NextFunction) {
  const token = req.cookies?.session;
  if (!getSession(token)) {
    res.status(401).json({ error: "Unauthorized" });
    return;
  }
  next();
}

function cleanupSessions() {
  const now = Date.now();
  for (const [token, session] of sessions.entries()) {
    if (now - session.lastAccess > SESSION_TTL) {
      sessions.delete(token);
    }
  }
}
setInterval(cleanupSessions, 5 * 60 * 1000);

let isRunning = false;

async function runParser(): Promise<void> {
  if (isRunning) return;
  isRunning = true;

  const state = await resetState();

  try {
    const config = await loadConfig(process.env.NOVAVPS_URL || "");
    const novavpsUrl = config.novavpsUrl;

    if (!novavpsUrl) {
      state.status = "error";
      state.currentStep = "novavps_url_missing";
      await saveState(state);
      return;
    }

    const panels = getPanels();
    if (panels.length === 0) {
      state.status = "error";
      state.currentStep = "no_xray_panels";
      await saveState(state);
      return;
    }

    state.currentStep = "novavps_fetching";
    await saveState(state);

    let novavpsConnections: Awaited<ReturnType<typeof parseNovavps>> = [];
    try {
      novavpsConnections = await parseNovavps(novavpsUrl);
      state.novavps = {
        status: "success",
        count: novavpsConnections.length,
        timestamp: new Date().toISOString(),
        error: null,
      };
    } catch (err) {
      state.novavps = {
        status: "error",
        count: 0,
        timestamp: new Date().toISOString(),
        error: err instanceof Error ? err.message : String(err),
      };
    }
    await saveState(state);

    const valid = getValidConnections(novavpsConnections);

    for (const panel of panels) {
      state.currentStep = `${panel.label}_parsing`;
      await saveState(state);

      try {
        const xray = await parseXrayPanel(panel.url, panel.username, panel.password);
        const panelStateKey = panel.label as "xray1" | "xray2";
        state[panelStateKey] = {
          status: "success",
          outboundsCount: xray.length,
          synced: false,
          syncedOutbounds: [],
          timestamp: new Date().toISOString(),
          error: null,
        };
      } catch (err) {
        const errorState = {
          status: "error" as const,
          outboundsCount: 0,
          synced: false,
          syncedOutbounds: [],
          timestamp: new Date().toISOString(),
          error: err instanceof Error ? err.message : String(err),
        };
        if (panel.label === "xray1") {
          state.xray1 = errorState;
        } else {
          state.xray2 = errorState;
        }
      }
      await saveState(state);

      if (valid.length > 0) {
        state.currentStep = `${panel.label}_syncing`;
        await saveState(state);

        try {
          await syncNovavpsToXray(valid, panel.url, panel.username, panel.password, panel.label);
          const syncedTags = valid.map((_, idx) => `novavps${idx + 1}`);
          const panelStateKey = panel.label as "xray1" | "xray2";
          state[panelStateKey].synced = true;
          state[panelStateKey].syncedOutbounds = syncedTags;
        } catch (err) {
          const errMsg = err instanceof Error ? err.message : String(err);
          if (panel.label === "xray1") {
            state.xray1.error = errMsg;
          } else {
            state.xray2.error = errMsg;
          }
        }
        await saveState(state);
      }
    }

    state.status = "completed";
    state.currentStep = "done";
    await saveState(state);
  } catch (err) {
    state.status = "error";
    state.currentStep = "fatal";
    if (state.novavps.status === "idle") {
      state.novavps = { status: "error", count: 0, timestamp: new Date().toISOString(), error: err instanceof Error ? err.message : String(err) };
    }
    await saveState(state);
  } finally {
    await closeBrowser();
    isRunning = false;
  }
}

app.post("/api/login", async (req: Request, res: Response) => {
  const { username, password } = req.body;
  if (!username || !password) {
    res.status(400).json({ error: "username and password required" });
    return;
  }
  if (!validCredentials(username, password)) {
    res.status(401).json({ error: "Invalid credentials" });
    return;
  }
  const token = createSession();
  res.cookie("session", token, {
    httpOnly: true,
    sameSite: "strict",
    maxAge: SESSION_TTL,
    path: "/",
  });
  res.json({ ok: true });
});

app.post("/api/logout", (_req: Request, res: Response) => {
  res.clearCookie("session");
  res.json({ ok: true });
});

app.get("/api/status", authMiddleware, async (_req: Request, res: Response) => {
  const state = await loadState();
  res.json(state);
});

app.post("/api/run", authMiddleware, async (_req: Request, res: Response) => {
  if (isRunning) {
    res.status(409).json({ error: "Parser already running" });
    return;
  }
  runParser().catch((err) => console.error("[server] Parser error:", err));
  res.json({ ok: true, message: "Parser started" });
});

app.get("/api/config", authMiddleware, async (_req: Request, res: Response) => {
  const config = await loadConfig(process.env.NOVAVPS_URL || "");
  res.json(config);
});

app.put("/api/config", authMiddleware, async (req: Request, res: Response) => {
  const { novavpsUrl } = req.body;
  if (!novavpsUrl) {
    res.status(400).json({ error: "novavpsUrl required" });
    return;
  }
  const config = await loadConfig(process.env.NOVAVPS_URL || "");
  config.novavpsUrl = novavpsUrl;
  await saveConfig(config);
  res.json({ ok: true });
});

app.get("/api/data/novavps", authMiddleware, async (_req: Request, res: Response) => {
  const filePath = path.resolve(__dirname, "..", "data", "novavps-connections.json");
  try {
    const raw = await fs.readFile(filePath, "utf-8");
    res.json(JSON.parse(raw));
  } catch {
    res.json([]);
  }
});

app.get("/api/data/xray", authMiddleware, async (_req: Request, res: Response) => {
  const filePath = path.resolve(__dirname, "..", "data", "xray-outbounds.json");
  try {
    const raw = await fs.readFile(filePath, "utf-8");
    res.json(JSON.parse(raw));
  } catch {
    res.json([]);
  }
});

(async () => {
  const config = await loadConfig(process.env.NOVAVPS_URL || "");

  app.listen(PORT, "0.0.0.0", () => {
    console.log(`[server] Web interface running on http://0.0.0.0:${PORT}`);
    console.log(`[server] NOVAVPS_URL: ${config.novavpsUrl || "(not set)"}`);
    console.log(`[server] Panels: ${getPanels().map((p) => p.label).join(", ") || "(none)"}`);
  });
})();