import { describe, it, expect } from "vitest";
import { readFileSync } from "node:fs";
import { join } from "node:path";
import {
  assertJournalMonotonic,
  formatJournalViolations,
  type JournalEntry,
} from "@cmbot/db/journal-check";

/**
 * CI guard against the recurring drizzle journal-skip bug.
 *
 * Drizzle's migrator orders entries by `when` (not `idx`) and only
 * applies entries whose `when` is greater than the latest applied
 * row's recorded `created_at`. We've shipped two breaking deploys
 * (0010/0011 and 0012/0013) where freshly-generated migrations had
 * `when` values older than a prior manually-bumped entry — `pnpm
 * migrate` printed "Migrations applied." while silently skipping
 * the new SQL, and production 500'd until we hand-fixed the journal.
 *
 * This test reads the committed _journal.json and fails if the
 * entries aren't strictly monotonically increasing by `when` in the
 * same order as `idx`. Catches a bad commit at PR time instead of
 * at the next deploy.
 */
describe("drizzle journal monotonicity (regression guard)", () => {
  const journalPath = join(
    __dirname,
    "..",
    "..",
    "..",
    "..",
    "packages",
    "db",
    "migrations",
    "meta",
    "_journal.json",
  );

  const raw = JSON.parse(readFileSync(journalPath, "utf8")) as {
    entries: JournalEntry[];
  };

  it("loads at least one journal entry (sanity)", () => {
    expect(raw.entries.length).toBeGreaterThan(0);
  });

  it("`when` timestamps are strictly increasing in `idx` order", () => {
    const result = assertJournalMonotonic(raw.entries);
    if (!result.ok) {
      // Print the same actionable message migrate.ts prints, so a
      // failed CI run reads exactly like a failed local migrate.
      // eslint-disable-next-line no-console
      console.error(formatJournalViolations(result));
    }
    expect(result.violations).toEqual([]);
    expect(result.ok).toBe(true);
  });
});