/**
 * @module tests/unit/transaction/timeout-never-internally-retried
 * @description Regression pin for the no-hot-retry contract (8.10.1).
 *
 * A production incident: a native-provider op ground 38-40s inside a
 * transaction, blew the ~32s budget, was rolled back, and a CONSUMER pipeline
 * hot-retried the identical operation into a 6-minute 100%-CPU storm.
 * Investigation established brainy itself never auto-retries a
 * `TransactionTimeoutError` — the storm was entirely the consumer's hot-retry
 * loop, driven by a "retryable" doc-prose claim with no machine-readable
 * contract. This file pins the brainy-side half of that story so it can never
 * regress silently:
 *
 * (i)  the underlying engine (`TransactionManager.executeTransaction()` →
 *      `Transaction.execute()`) — the exact machinery every single-record
 *      write (`add`/`update`/`remove`/...) drives via
 *      `Brainy.persistSingleOp()` — never internally re-executes a timed-out
 *      operation, and the error it surfaces carries `retryable === true` and
 *      `hotRetryUnsafe === true` (see `src/transaction/errors.ts`).
 *
 *      Constructed directly (mirrors the existing
 *      `tests/unit/transaction/timeout-rollback.test.ts` pattern) rather than
 *      through a real `brain.add()` call: `transactTimeoutBudget()` floors
 *      every single-op write's budget at `opCount * 2000`ms with NO override
 *      seam (`transactionBudgetFloorMs` only RAISES that floor — it cannot
 *      lower it below the per-op-count term), so getting a real `add()` to
 *      time out requires a multi-second sleep. The engine-level
 *      `options.timeout` override used here is the exact same
 *      `TransactionManager`/`Transaction` code `persistSingleOp` calls —
 *      pinning it here pins add()'s guarantee without paying that wall-clock
 *      cost.
 *
 * (ii) `Brainy.add()`'s upsert-race retry loop (src/brainy.ts,
 *      `MAX_UPSERT_ATTEMPTS = 10`) — proving the loop's `catch` treats a
 *      `TransactionTimeoutError` as terminal (immediate rethrow) rather than
 *      the `InsertPreconditionExistsSignal` it retries on, so a mid-flight
 *      timeout can never be silently swallowed and re-attempted up to 10
 *      times.
 */
import { describe, it, expect } from 'vitest'
import { TransactionManager } from '../../../src/transaction/TransactionManager.js'
import type { Operation, RollbackAction } from '../../../src/transaction/types.js'
import { TransactionTimeoutError } from '../../../src/transaction/errors.js'
import { Brainy } from '../../../src/brainy.js'
import { NounType } from '../../../src/types/graphTypes.js'

const sleep = (ms: number) => new Promise<void>((r) => setTimeout(r, ms))

// Brainy's ValidationConfig fixes vectors at exactly 384 dimensions
// (src/utils/paramValidation.ts) — match it so add() doesn't reject test data.
const DIM = 384
const V = (): number[] => Array(DIM).fill(0.1)

/** An operation that counts every `execute()` invocation — the re-drive detector. */
function countingOp(opts: { delayMs?: number; name: string }): Operation & { calls: number } {
  const op = {
    name: opts.name,
    calls: 0,
    async execute(): Promise<RollbackAction | undefined> {
      op.calls++
      if (opts.delayMs) await sleep(opts.delayMs)
      return async () => {}
    }
  }
  return op
}

describe('transaction timeouts are never internally re-driven (8.10.1 no-hot-retry contract)', () => {
  it('(i) the single-op engine (TransactionManager.executeTransaction / Transaction.execute — what add() drives via persistSingleOp) runs the overrun operation EXACTLY once and surfaces ONE retryable+hotRetryUnsafe error', async () => {
    const manager = new TransactionManager()
    const op0 = countingOp({ name: 'op0-overruns-budget', delayMs: 30 })
    const op1 = countingOp({ name: 'op1-must-never-start' })

    let caught: unknown
    try {
      await manager.executeTransaction(
        async (tx) => {
          tx.addOperation(op0)
          tx.addOperation(op1)
        },
        // Tiny explicit override — the same override seam `transact()`
        // exposes as `options.timeoutMs`; wins outright over the
        // opCount*2000 floor that gates every real single-op write
        // (transactTimeoutBudget()'s override semantics).
        { timeout: 5 }
      )
    } catch (err) {
      caught = err
    }

    expect(caught).toBeInstanceOf(TransactionTimeoutError)
    const err = caught as TransactionTimeoutError
    // The machine-readable contract callers branch on instead of parsing
    // message text (src/transaction/errors.ts).
    expect(err.retryable).toBe(true)
    expect(err.hotRetryUnsafe).toBe(true)

    // The re-drive assertion: op0 (the one that overran) executed EXACTLY
    // once — nothing inside TransactionManager/Transaction looped back and
    // re-ran it — and op1 never started at all (the budget gate stopped it
    // before it began, per Transaction.execute()'s per-operation loop).
    expect(op0.calls).toBe(1)
    expect(op1.calls).toBe(0)
  })

  it('(ii) add()\'s upsert-race retry loop (MAX_UPSERT_ATTEMPTS=10) exits on the FIRST TransactionTimeoutError — attempt counter stays at 1, never mistaken for the lost-insert-race signal it retries on', async () => {
    const brain = new Brainy({
      requireSubtype: false,
      storage: { type: 'memory' },
      silent: true
    })
    await brain.init()

    let persistSingleOpCalls = 0
    const timeoutError = new TransactionTimeoutError(5, 1, {
      elapsedMs: 6,
      totalOperations: 2,
      operationName: 'SaveNounMetadata'
    })
    // Stub the private commit seam add() drives (persistSingleOp) to throw
    // the exact error type the real engine surfaces on a mid-flight timeout.
    // This test pins the upsert loop's EXCEPTION-HANDLING contract (does it
    // retry a TransactionTimeoutError like it retries
    // InsertPreconditionExistsSignal?), not the timing mechanics of a real
    // timeout — those are pinned by test (i) and by
    // tests/unit/transaction/timeout-rollback.test.ts.
    ;(brain as any).persistSingleOp = async (): Promise<never> => {
      persistSingleOpCalls++
      throw timeoutError
    }

    await expect(
      brain.add({ data: 'a', type: NounType.Thing, vector: V() })
    ).rejects.toBe(timeoutError)

    // The loop's attempt counter: exactly one call, never retried up to
    // MAX_UPSERT_ATTEMPTS.
    expect(persistSingleOpCalls).toBe(1)
    await brain.close()
  })
})