const http = require("http");
const fs = require("fs");
const path = require("path");

const PORT = process.env.PORT || 3000;
const DATA = path.join(__dirname, "data.json");

function readData() {
  try { return JSON.parse(fs.readFileSync(DATA, "utf8")); } catch (_) { return { items: [], log: [] }; }
}
function writeData(d) { fs.writeFileSync(DATA, JSON.stringify(d, null, 2)); }
function body(req) {
  return new Promise((resolve) => {
    let s = "";
    req.on("data", (c) => (s += c));
    req.on("end", () => { try { resolve(JSON.parse(s || "{}")); } catch (_) { resolve({}); } });
  });
}

http.createServer(async (req, res) => {
  const url = req.url.split("?")[0];
  res.setHeader("Content-Type", "application/json; charset=utf-8");

  // API: все карточки кандидата
  if (req.method === "GET" && url === "/api/cards") {
    const d = readData();
    res.end(JSON.stringify(d.items || []));
    return;
  }

  // API: получить одну карточку
  if (req.method === "GET" && url.startsWith("/api/cards/")) {
    const id = url.split("/").pop();
    const d = readData();
    const card = (d.items || []).find((x) => String(x.id) === String(id));
    if (!card) { res.writeHead(404); res.end(JSON.stringify({ error: "not found" })); return; }
    res.end(JSON.stringify(card));
    return;
  }

  // API: создать новую карточку
  if (req.method === "POST" && url === "/api/cards") {
    const b = await body(req);
    const d = readData();
    const card = {
      id: Date.now(),
      name: b.name || "",
      post: b.post || "",
      submitted: new Date().toISOString().slice(0, 10),
      stage: "uploaded",
      files: [],
      analysisStatus: "idle",
      violations: [],
      checks: {},
      text: "",
      sentAt: null,
      returned: null,
      approvedAt: null,
      createdAt: new Date().toISOString()
    };
    d.items.push(card);
    d.log = d.log || [];
    d.log.push({ when: new Date().toISOString(), what: "Создана карточка «" + card.name + "»" });
    writeData(d);
    res.end(JSON.stringify(card));
    return;
  }

  // API: обновить карточку
  if (req.method === "PUT" && url.startsWith("/api/cards/")) {
    const id = url.split("/").pop();
    const b = await body(req);
    const d = readData();
    const idx = (d.items || []).findIndex((x) => String(x.id) === String(id));
    if (idx === -1) { res.writeHead(404); res.end(JSON.stringify({ error: "not found" })); return; }
    d.items[idx] = Object.assign(d.items[idx], b, { id });
    d.log = d.log || [];
    d.log.push({ when: new Date().toISOString(), what: "Обновлена карточка «" + d.items[idx].name + "»" });
    writeData(d);
    res.end(JSON.stringify(d.items[idx]));
    return;
  }

  // Статика
  let file = url === "/" ? "/index.html" : url;
  const full = path.join(__dirname, file);
  if (full.startsWith(__dirname) && fs.existsSync(full) && fs.statSync(full).isFile()) {
    const ext = path.extname(full);
    const type = ext === ".css" ? "text/css" : ext === ".js" ? "application/javascript" : "text/html";
    res.writeHead(200, { "Content-Type": type + "; charset=utf-8" });
    res.end(fs.readFileSync(full));
    return;
  }
  res.writeHead(404); res.end("Not found");
}).listen(PORT, () => console.log("Сервер на порту " + PORT));