import express from "express";
import session from "express-session";
import path from "node:path";
import { fileURLToPath } from "node:url";
import { loadUser } from "./middleware/auth.js";
import { notFoundHandler, errorHandler } from "./middleware/errors.js";
import { pagesRouter } from "./routes/pages.routes.js";
import { entriesRouter } from "./routes/entries.routes.js";
import { tagsRouter } from "./routes/tags.routes.js";
import { commentsRouter } from "./routes/comments.routes.js";
import { adminRouter } from "./routes/admin.routes.js";
import { mcpRouter } from "./mcp/server.js";

const here = path.dirname(fileURLToPath(import.meta.url));

export function buildApp(config) {
  const app = express();
  app.disable("x-powered-by");
  app.set("view engine", "ejs");
  app.set("views", path.join(here, "views"));

  app.locals.config = config;
  app.locals.fmtStars = (n) => {
    const v = Number(n) || 0;
    return v >= 1000 ? (v / 1000).toFixed(1) + "k" : String(v);
  };
  app.locals.fmtDate = (d) =>
    d ? new Date(d).toISOString().slice(0, 10) : "—";
  app.locals.qs = (obj) => {
    const p = new URLSearchParams();
    for (const [k, v] of Object.entries(obj)) {
      if (Array.isArray(v)) {
        if (v.length) p.set(k, v.join(","));
      } else if (v !== undefined && v !== null && String(v) !== "") {
        p.set(k, v);
      }
    }
    const s = p.toString();
    return s;
  };

  app.use(express.json({ limit: "1mb" }));
  app.use(express.urlencoded({ extended: true }));
  app.use(
    session({
      secret: config.sessionSecret,
      resave: false,
      saveUninitialized: false,
      cookie: { httpOnly: true, sameSite: "lax", maxAge: 1000 * 60 * 60 * 24 * 14 },
    })
  );
  app.use(loadUser);
  app.use(express.static(path.join(here, "..", "public")));

  app.use(pagesRouter);
  app.use(entriesRouter);
  app.use(tagsRouter);
  app.use(commentsRouter);
  app.use(adminRouter);
  app.use(mcpRouter);

  app.use(notFoundHandler);
  app.use(errorHandler);
  return app;
}