import { readFileSync } from "node:fs";
import { join } from "node:path";
import { describe, expect, it } from "vitest";

const root = process.cwd();

const locales = {
  da: JSON.parse(readFileSync(join(root, "src/i18n/locales/da.json"), "utf8")),
  en: JSON.parse(readFileSync(join(root, "src/i18n/locales/en.json"), "utf8")),
  sv: JSON.parse(readFileSync(join(root, "src/i18n/locales/sv.json"), "utf8")),
  de: JSON.parse(readFileSync(join(root, "src/i18n/locales/de.json"), "utf8")),
  no: JSON.parse(readFileSync(join(root, "src/i18n/locales/no.json"), "utf8")),
};

const flattenKeys = (value, prefix = "") => {
  if (value === null || typeof value !== "object" || Array.isArray(value)) {
    return [prefix];
  }

  const keys = [];
  for (const [key, nestedValue] of Object.entries(value)) {
    const nestedPrefix = prefix ? `${prefix}.${key}` : key;
    keys.push(...flattenKeys(nestedValue, nestedPrefix));
  }
  return keys;
};

describe("invoice distribution i18n coverage", () => {
  it("defines distribution namespace in every locale", () => {
    for (const [locale, data] of Object.entries(locales)) {
      expect(data.superuser_invoice_distribution, `missing namespace in ${locale}`).toBeTruthy();
    }
  });

  it("keeps the same translation key set across locales", () => {
    const baselineKeys = flattenKeys(locales.en.superuser_invoice_distribution).sort();

    for (const [locale, data] of Object.entries(locales)) {
      const localeKeys = flattenKeys(data.superuser_invoice_distribution).sort();
      expect(localeKeys, `mismatched key set in ${locale}`).toEqual(baselineKeys);
    }
  });

  it("includes required distribution keys used by views", () => {
    const requiredKeys = [
      "tab_label",
      "overview.title",
      "overview.subtitle",
      "monthly_page.title",
      "monthly_page.toolbar_month",
      "actions.reload",
      "actions.open_month",
      "actions.try_again",
      "actions.reset_filters",
      "tabs.overview",
      "tabs.departments",
      "tabs.customers",
      "tabs.compare",
      "compare.mode",
      "compare.modes.invoice_total",
      "compare.modes.line_by_line",
      "compare.run",
      "compare.run_short",
      "compare.progress",
      "compare.warning_details",
      "compare.status_label",
      "compare.status.ok",
      "compare.status.mismatch",
      "errors.overview_load_failed",
      "errors.month_load_failed",
      "errors.compare_failed",
      "warnings.legacy_distribution_fallback",
      "warnings.legacy_distribution_month",
      "warnings.legacy_compare_fallback",
      "sections.trend",
      "metrics.customer_prices",
      "table.customer_prices",
      "table.source_mix",
      "aria.month_table_caption",
      "aria.compare_table_caption",
    ];

    const availableKeys = new Set(flattenKeys(locales.en.superuser_invoice_distribution));
    requiredKeys.forEach((key) => {
      expect(availableKeys.has(key)).toBe(true);
    });
  });
});