import fs from "fs";
import path from "path";
import type { TableConfig } from "./schema";

const TABLE_CONFIG_FILE = path.join(process.cwd(), "data", "table-config.json");

const SYSTEM_COLUMNS = ["id", "dataobnovleniyazapisi"];

const DEFAULT_COLUMN_LABELS: Record<string, string> = {
  data: "Дата",
  summa: "Сумма",
  summadokumenta: "Сумма документа",
  statya: "Статья",
  zakazchik: "Заказчик",
  dochka: "Дочка",
  vnuchka: "Внучка",
  kommentarii: "Комментарий",
  stavkands: "Ставка НДС",
  naznachenieplatezha: "Назначение платежа",
  otvetstvenniipokontraktu: "Ответственный",
  dogovorkontragenta: "Договор контрагента",
  dogovorzakazchika: "Договор заказчика",
  statyadop: "Статья (доп.)",
  schetnaoplatu: "Счет на оплату",
  nomervhodyaschegodokumenta: "Номер вх. документа",
  ssilkanomervhodyaschegodokumenta: "Номер вх. документа",
  kontragent: "Контрагент",
  dogovor: "Договор",
  summadolga: "Сумма долга",
  summaprosrocheno: "Сумма просрочено",
  period: "Период",
  klassprosrochki: "Класс просрочки",
  otvetstvennii: "Ответственный",
  organizaciya: "Организация",
  dokumentraschetov: "Документ расчётов",
  summaoplacheno: "Сумма оплачено",
  dneiprosrocheno: "Дней просрочено",
  dneidolga: "Дней долга",
  dataobrazovaniyadolga: "Дата образования долга",
  planovayadatapogasheniya: "Плановая дата погашения",
  otsrochkapodogovoru: "Отсрочка по договору",
  kontragentinn: "ИНН контрагента",
  valyuta: "Валюта",
  summadolgaval: "Сумма долга (вал.)",
  schet: "Счёт",
  klassdolga: "Класс долга",
  dataobnovleniyazapisi: "Дата обновления",
};

export const DEFAULT_TABLE_CONFIG: TableConfig = {
  incomeTable: "opdohodi",
  expenseTable: "oprashodi",
  debtTable: "vw_debt_active",
  incomeSumColumn: "summa",
  expenseSumColumn: "summadokumenta",
  incomeColumns: ["id", "data", "summa", "statya", "zakazchik", "dochka", "vnuchka", "kommentarii", "stavkands", "naznachenieplatezha", "otvetstvenniipokontraktu", "dogovorkontragenta", "schetnaoplatu", "dogovorzakazchika", "statyadop", "nomervhodyaschegodokumenta", "dataobnovleniyazapisi"],
  expenseColumns: ["id", "data", "summadokumenta", "statya", "zakazchik", "dochka", "vnuchka", "kommentarii", "stavkands", "naznachenieplatezha", "otvetstvenniipokontraktu", "dogovorkontragenta", "dogovorzakazchika", "statyadop", "ssilkanomervhodyaschegodokumenta", "kontragent", "dataobnovleniyazapisi"],
  columnLabels: { ...DEFAULT_COLUMN_LABELS },
};

let cachedConfig: TableConfig | null = null;

export function loadTableConfig(): TableConfig {
  if (cachedConfig) return cachedConfig;
  try {
    const raw = fs.readFileSync(TABLE_CONFIG_FILE, "utf-8");
    const parsed = JSON.parse(raw);
    cachedConfig = { ...DEFAULT_TABLE_CONFIG, ...parsed, columnLabels: { ...DEFAULT_COLUMN_LABELS, ...(parsed.columnLabels || {}) } };
    return cachedConfig!;
  } catch {
    cachedConfig = { ...DEFAULT_TABLE_CONFIG };
    return cachedConfig;
  }
}

export function saveTableConfig(cfg: Partial<TableConfig>) {
  const current = loadTableConfig();
  const merged: TableConfig = {
    ...current,
    ...cfg,
    columnLabels: { ...current.columnLabels, ...(cfg.columnLabels || {}) },
  };
  if (!fs.existsSync("data")) fs.mkdirSync("data", { recursive: true });
  fs.writeFileSync(TABLE_CONFIG_FILE, JSON.stringify(merged, null, 2), "utf-8");
  cachedConfig = merged;
}

export function getIncomeTable(): string {
  return "vw_income_effective";
}

export function getExpenseTable(): string {
  return "vw_expense_effective";
}

export function getIncomeBaseTable(): string {
  return loadTableConfig().incomeTable;
}

export function getExpenseBaseTable(): string {
  return loadTableConfig().expenseTable;
}

export function getIncomeEffectiveView(): string {
  return "vw_income_effective";
}

export function getExpenseEffectiveView(): string {
  return "vw_expense_effective";
}

export function getDebtTable(): string {
  return loadTableConfig().debtTable;
}

export function getIncomeSumColumn(): string {
  return loadTableConfig().incomeSumColumn;
}

export function getExpenseSumColumn(): string {
  return loadTableConfig().expenseSumColumn;
}

export function getAllowedIncomeColumns(): string[] {
  const cfg = loadTableConfig();
  return cfg.incomeColumns.filter(c => !SYSTEM_COLUMNS.includes(c));
}

export function getAllowedExpenseColumns(): string[] {
  const cfg = loadTableConfig();
  return cfg.expenseColumns.filter(c => !SYSTEM_COLUMNS.includes(c));
}

export function getAutoDetectAllowedColumns(type: "income" | "expense"): string[] {
  const allowed = type === "income" ? getAllowedIncomeColumns() : getAllowedExpenseColumns();
  return allowed.filter(c => c !== "data" && c !== "id" && c !== "summa" && c !== "summadokumenta" && c !== "dataobnovleniyazapisi");
}

export function getColumnLabel(col: string): string {
  const cfg = loadTableConfig();
  return cfg.columnLabels[col] || col;
}

export function getAllIncomeColumns(): string[] {
  return loadTableConfig().incomeColumns;
}

export function getAllExpenseColumns(): string[] {
  return loadTableConfig().expenseColumns;
}

export function invalidateTableConfigCache() {
  cachedConfig = null;
}