"use strict";

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

const DATA_FILE = path.join(__dirname, "..", "data.json");
const UPLOADS_DIR = path.join(__dirname, "..", "uploads");

const DEFAULT_DEADLINE = "2026-10-15";

const START_COMPANIES = [
  "АО «НК «КазМунайГаз»",
  "АО «НК «КТЖ»",
  "АО «Казахтелеком»",
  "АО «KEGOC»",
  "АО «НАК «Казатомпром»",
  "АО «Казпочта»",
  "АО «Самрук-Энерго»",
  "ТОО «Самрук-Казына Инвест»",
  "ТОО «Самрук-Казына Контракт»",
  "ТОО «Samruk-Kazyna Ondeu»",
  "АО «НГК «Таукен Самрук»",
  "АО «Samruk-Kazyna Construction»",
  "АО «НК «QazaqGaz»",
  "ТОО «ПГУ Туркестан»",
  "АО «ФНБ «Самрук-Казына»",
];

function ensureUploadsDir() {
  if (!fs.existsSync(UPLOADS_DIR)) fs.mkdirSync(UPLOADS_DIR, { recursive: true });
}

function readRaw() {
  if (!fs.existsSync(DATA_FILE)) return null;
  try {
    return JSON.parse(fs.readFileSync(DATA_FILE, "utf8"));
  } catch (e) {
    return null;
  }
}

function writeRaw(db) {
  fs.writeFileSync(DATA_FILE, JSON.stringify(db, null, 2));
}

function randPassword(len) {
  const abc = "ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz23456789";
  let s = "";
  const buf = crypto.randomBytes(len);
  for (let i = 0; i < len; i++) s += abc[buf[i] % abc.length];
  return s;
}

function makeUser(record) {
  const salt = crypto.randomBytes(32);
  const pw = randPassword(12);
  const hash = crypto.scryptSync(pw, salt, 32);
  return Object.assign(
    { failedCount: 0, lockedUntil: 0 },
    record,
    {
      salt: salt.toString("hex"),
      passwordHash: hash.toString("hex"),
      active: true,
    }
  );
}

function seed() {
  ensureUploadsDir();
  const db = {
    period: "3-й квартал 2026",
    deadline: DEFAULT_DEADLINE,
    consolidatorPhone: "",
    users: [],
    reports: [],
  };
  const consPw = randPassword(12);
  const cons = makeUser({
    id: "u_consolidator",
    role: "consolidator",
    name: "",
    companyName: "",
    login: "svod",
  });
  db._consolidatorTempPassword = consPw;
  db.users.push(cons);
  START_COMPANIES.forEach(function (name, i) {
    const u = makeUser({
      id: "u_" + i,
      role: "subsidiary",
      name: "",
      companyName: name,
      person: "",
      phone: "",
      login: "c" + (i + 1),
    });
    db.users.push(u);
  });
  writeRaw(db);
  return db;
}

function load() {
  let db = readRaw();
  if (!db || !Array.isArray(db.users) || !Array.isArray(db.reports)) {
    db = seed();
  }
  if (!Array.isArray(db.reports)) db.reports = [];
  if (!db.period) db.period = "3-й квартал 2026";
  if (!db.deadline) db.deadline = DEFAULT_DEADLINE;
  db.users.forEach(function (u) {
    if (typeof u.failedCount !== "number") u.failedCount = 0;
    if (typeof u.lockedUntil !== "number") u.lockedUntil = 0;
    if (typeof u.active !== "boolean") u.active = true;
  });
  return db;
}

function save(db) {
  writeRaw(db);
}

function genId(prefix) {
  return prefix + "_" + Date.now().toString(36) + "_" + crypto.randomBytes(4).toString("hex");
}

function hashPassword(password, saltHex) {
  const salt = Buffer.from(saltHex, "hex");
  return crypto.scryptSync(password, salt, 32).toString("hex");
}

function verifyPassword(password, saltHex, expectedHex) {
  const hash = Buffer.from(hashPassword(password, saltHex), "hex");
  const expected = Buffer.from(expectedHex, "hex");
  return hash.length === expected.length && crypto.timingSafeEqual(hash, expected);
}

module.exports = {
  DATA_FILE: DATA_FILE,
  UPLOADS_DIR: UPLOADS_DIR,
  ensureUploadsDir: ensureUploadsDir,
  randPassword: randPassword,
  makeUser: makeUser,
  load: load,
  save: save,
  genId: genId,
  START_COMPANIES: START_COMPANIES,
  verifyPassword: verifyPassword,
};