const assert = require('node:assert/strict')
const crypto = require('node:crypto')
const fs = require('node:fs')
const path = require('node:path')

const sixthRecoveryScope = Object.freeze({ tenant_id: 10059, dead_letter_id: 10,
  knowledge_id: 'd52e5191-1129-4934-be64-3dcc0651e52b',
  knowledge_base_id: '5d28a7e5-e00e-44a7-a0e1-c72342cdcf68',
  model_id: '404e005b-83ae-5e2e-a3b3-999f9d5cd47e',
  embedding_model_id: 'a2c3ce32-6192-46c8-8072-910abfe8afed',
  source_fingerprint: 'e6198cf7c0c3de64150a2f3944c986ee4fffaa347d31e560d8ea3d4994c92a07',
  model_fingerprint: 'e57322463beae82b3d8876f4735637b30b2bc5f65dcd716f9f26d4bcc677a12c' })
const sixthGuardPausedOperation = Object.freeze({ id: 4144, tenant_id: sixthRecoveryScope.tenant_id,
  task_type: 'wiki:ingest', scope: 'knowledge_base', scope_id: sixthRecoveryScope.knowledge_base_id,
  op: 'ingest', dedup_key: sixthRecoveryScope.knowledge_id, fail_count: 5,
  payload: Object.freeze({ op: 'ingest', knowledge_id: sixthRecoveryScope.knowledge_id,
    recovery_dead_letter_id: 10, recovery_attempt: 5, recovery_pending_op_id: 4144, recovery_budget_version: 1 }) })
const diagnosticPins = Object.freeze({
  release: 'public-20260920-223700', image: 'sha256:7161342591c754fa734a486e0dd56a892f0d404c97b4a524381d244a594d575e',
  source: '0e250d6605cc2ee40da694608b5b410ff92b504660d6ee38ead11e15cbf7846a',
  window: 'f2e3cb37e496df4d93d56586d9659c7ae680cc8dc8e5476136dd02d044bd908a', start: 32750, end: 65497,
})
const replayPins = Object.freeze({
  kind: 'candidate_layout_identity_replay_v1',
  input_run_id: 'b3cf4f6a-b734-48f3-90f8-61be44b3d813',
  input_evidence_sha256: 'b26a2ec44eeb386a7de9750566b350b6940b8abded8ca28a607d821af1ba7dbe',
  source_window_sha256: '4f61cde7c750c4ec4052ccb01626ea6122ff8d79c527c4c34abd51b9679d3d65',
  response_sha256: '39ce646b91e05437a1ad4d9ee28524048be8fdc751ecce935c3da86eed0c63d5',
})
const sha = value => crypto.createHash('sha256').update(value).digest('hex')

function validateSixthRecoveryReview(review, now = Date.now()) {
  assert.equal(review?.max_attempt, 6, 'Sixth recovery requires its own review')
  for (const [key, value] of Object.entries(sixthRecoveryScope)) assert.equal(review[key], value, `Sixth recovery review mismatch: ${key}`)
  assert.equal(review.previous_attempt, 5, 'Sixth recovery requires attempt five')
  assert.equal(review.previous_pending_op_id, 4144, 'Sixth recovery requires exact operation 4144')
  assert.equal(review.previous_error_code, 'EXTRACT_FAILED', 'Sixth recovery requires the reviewed extraction failure')
  assert.equal(review.budget_version, 1, 'Sixth recovery requires its own durable budget')
  assert.ok(Number.isSafeInteger(review.max_provider_requests) && review.max_provider_requests > 0 && review.max_provider_requests <= 1000, 'Sixth recovery request limit must be 1..1000')
  const start = Date.parse(review.budget_started_at), deadline = Date.parse(review.deadline_at)
  assert.ok(Number.isFinite(start) && start <= now && deadline > start && deadline - start <= 120 * 60000, 'Sixth recovery needs a fixed duration of at most 120 minutes')
  assert.equal(review.public_gates_passed, true, 'Sixth recovery requires fresh public verification')
  assert.ok(review.fix_release > diagnosticPins.release, 'Sixth recovery requires the newer published candidate fix')
  assert.notEqual(review.api_image_id, diagnosticPins.image, 'Sixth recovery cannot use the pre-repair image')
  const diagnostic = review.candidate_diagnostic
  assert.ok(['candidate_repair_window_v3', replayPins.kind].includes(diagnostic?.kind), 'Sixth recovery requires reviewed diagnostic or saved-response replay evidence')
  assert.match(diagnostic.run_id || '', /^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}$/, 'Missing diagnostic run identity')
  for (const key of ['evidence_sha256', 'source_tree_hash']) assert.match(diagnostic[key] || '', /^[a-f0-9]{64}$/, `Missing diagnostic ${key}`)
  assert.equal(diagnostic.semantic_reviewed, true, 'Successful parsing needs a separate semantic review')
}

function validateSixthRecovery(source, previous, review) {
  validateSixthRecoveryReview(review)
  for (const [key, value] of Object.entries(sixthRecoveryScope)) assert.equal(key === 'dead_letter_id' ? source.id : source[key], value, `Sixth recovery source mismatch: ${key}`)
  assert.equal(previous?.attempt_number, 5, 'Sixth recovery requires the exact preceding attempt')
  assert.equal(previous.pending_op_id, 4144, 'Sixth recovery requires exact preceding operation 4144')
  assert.equal(previous.recovery_status, 'stopped_budget', 'Attempt five must remain terminal')
  assert.equal(previous.error_code, 'EXTRACT_FAILED', 'Preceding extraction failure changed')
  assert.ok(!previous.pending && !previous.pending_finalize, 'Attempt five must be idle')
  const budget = previous.recovery_budget
  assert.equal(budget?.status, 'stopped_budget', 'Attempt five budget must remain terminal')
  for (const [key, value] of Object.entries(sixthRecoveryScope)) assert.equal(budget[key], value, `Preceding budget mismatch: ${key}`)
  assert.equal(budget.attempt_number, 5, 'Preceding budget attempt changed')
  assert.equal(budget.pending_op_id, 4144, 'Preceding budget operation changed')
  assert.ok(Number.isSafeInteger(previous.new_failures) && previous.new_failures >= 0, 'Invalid preceding failure count')
  if (previous.new_failures === 0) {
    // The durable guard preserves this failed operation before another dead letter.
    assert.equal(previous.span_status, 'failed', 'Guard pause requires the failed extraction span')
    assert.equal(budget.stop_reason, 'guard_rejected', 'Preceding guard stop reason changed')
    assert.equal(budget.last_phase, 'wiki_candidate_slug', 'Preceding guard phase changed')
    assert.equal(budget.reserved_provider_requests, 4, 'Preceding guard send count changed')
    assert.equal(typeof budget.paused_payload, 'string', 'Preceding paused operation is missing')
    const paused = JSON.parse(budget.paused_payload)
    assert.ok(Array.isArray(paused) && paused.length === 1, 'Expected exactly one paused operation')
    for (const [key, value] of Object.entries(sixthGuardPausedOperation)) {
      if (key === 'payload') {
        for (const [field, expected] of Object.entries(value)) assert.equal(paused[0]?.payload?.[field], expected, `Preceding paused payload changed: ${field}`)
      } else assert.equal(paused[0]?.[key], value, `Preceding paused operation changed: ${key}`)
    }
  }
}

function validateSixthDiagnosticEvidence(review, bytes, sourceTreeHash) {
  validateSixthRecoveryReview(review)
  assert.equal(review.candidate_diagnostic.kind, 'candidate_repair_window_v3', 'Expected original V3 evidence')
  assert.equal(sha(bytes), review.candidate_diagnostic.evidence_sha256, 'V3 evidence changed after review')
  const evidence = JSON.parse(bytes)
  assert.equal(evidence.run_id, review.candidate_diagnostic.run_id, 'V3 run changed after review')
  assert.equal(evidence.source_tree_hash, review.candidate_diagnostic.source_tree_hash, 'V3 candidate source changed')
  assert.equal(sourceTreeHash, evidence.source_tree_hash, 'Current candidate source differs from the tested V3 source')
  assert.equal(evidence.status, 'finished', 'V3 diagnostic did not finish')
  assert.equal(evidence.candidate_source_only, true, 'Expected candidate diagnostic')
  assert.equal(evidence.protected_state_unchanged, true, 'V3 changed protected state')
  assert.equal(evidence.previous_diagnostics_unchanged, true, 'V3 changed historical evidence')
  const pins = evidence.pins
  for (const [key, value] of Object.entries({ tenant: 10059, deadLetter: 10, priorAttempt: 5, priorOperation: 4144,
    document: sixthRecoveryScope.knowledge_id, kb: sixthRecoveryScope.knowledge_base_id, model: sixthRecoveryScope.model_id,
    embedding: sixthRecoveryScope.embedding_model_id, sourceFingerprint: sixthRecoveryScope.source_fingerprint,
    modelFingerprint: sixthRecoveryScope.model_fingerprint, release: diagnosticPins.release, image: diagnosticPins.image,
    maxSends: 21, durationMs: 900000 })) assert.equal(pins?.[key], value, `V3 scope mismatch: ${key}`)
  const outcome = evidence.outcome
  assert.equal(outcome?.status, 'exact_window_candidates_validated', 'V3 full window did not pass')
  assert.equal(outcome.source_hash, diagnosticPins.source, 'V3 source changed')
  assert.deepEqual(outcome.window, { start_rune: diagnosticPins.start, end_rune: diagnosticPins.end, sha256: diagnosticPins.window }, 'V3 window changed')
  assert.ok(Number.isSafeInteger(outcome.candidate_count) && outcome.candidate_count > 0, 'V3 returned no validated candidates')
  assert.ok(Number.isSafeInteger(evidence.actual_send_reservations) && evidence.actual_send_reservations >= 1 && evidence.actual_send_reservations <= 21, 'V3 send budget invalid')
  assert.equal(outcome.actual_send_reservations, evidence.actual_send_reservations, 'V3 send receipt mismatch')
  let cursor = diagnosticPins.start
  assert.ok(Array.isArray(outcome.leaves) && outcome.leaves.length > 0, 'V3 source coverage missing')
  for (const leaf of outcome.leaves) {
    assert.equal(leaf.start_rune, cursor, 'V3 source coverage has a gap')
    assert.ok(Number.isSafeInteger(leaf.end_rune) && leaf.end_rune > cursor && leaf.end_rune <= diagnosticPins.end, 'V3 source coverage range invalid')
    cursor = leaf.end_rune
  }
  assert.equal(cursor, diagnosticPins.end, 'V3 source coverage incomplete')
  assert.ok(Date.parse(review.published_at) > Date.parse(evidence.started_at), 'Published fix must follow candidate diagnostic')
}

// Replaying the unchanged failed response proves the mechanical repair without
// another provider request. The original failure remains a separate artifact.
function validateSixthReplayEvidence(review, bytes, sourceTreeHash) {
  validateSixthRecoveryReview(review)
  assert.equal(review.candidate_diagnostic.kind, replayPins.kind, 'Expected layout identity replay')
  assert.equal(sha(bytes), review.candidate_diagnostic.evidence_sha256, 'Replay evidence changed after review')
  const evidence = JSON.parse(bytes)
  for (const [key, value] of Object.entries(replayPins)) assert.equal(evidence[key], value, `Replay input changed: ${key}`)
  assert.equal(evidence.run_id, review.candidate_diagnostic.run_id, 'Replay run changed after review')
  assert.equal(evidence.source_tree_hash, review.candidate_diagnostic.source_tree_hash, 'Replay candidate source changed')
  assert.equal(sourceTreeHash, evidence.source_tree_hash, 'Current candidate source differs from the replayed source')
  for (const [key, value] of Object.entries({ status: 'passed', model_calls: 0, production_writes: 0,
    rejected_count: 0, source_preserved: true, original_receipt_preserved: true })) {
    assert.equal(evidence[key], value, `Replay did not satisfy ${key}`)
  }
  // The actual saved response has 22 entity identities and 67 concept identities.
  // No candidate may disappear merely because its generated slug collides.
  assert.equal(evidence.entity_count, 22, 'Replay lost an entity identity')
  assert.equal(evidence.concept_count, 67, 'Replay lost a concept identity')
  assert.equal(evidence.candidate_count, 89, 'Replay must preserve every distinct candidate identity')
  const start = Date.parse(evidence.started_at), end = Date.parse(evidence.completed_at)
  assert.ok(Number.isFinite(start) && end >= start, 'Replay timing is invalid')
  assert.ok(Date.parse(review.published_at) > end, 'Published fix must follow the replay')
}

function verifyReplayInputFiles(runtimeDirectory) {
  const directory = path.join(runtimeDirectory, 'acceptance/wiki-source-identity-diagnostic-private-20260921')
  const semantic = path.join(directory, `semantic-review-${replayPins.input_run_id}`)
  for (const [file, expected] of [
    [path.join(directory, 'evidence.json'), replayPins.input_evidence_sha256],
    [path.join(semantic, 'accepted/source-window.json'), replayPins.source_window_sha256],
    [path.join(semantic, 'responses/response-01.json'), replayPins.response_sha256],
  ]) assert.equal(sha(fs.readFileSync(file)), expected, 'Original replay input changed')
}

function candidateSourceTreeHash(sourceDirectory) {
  const files = ['go.mod', 'go.sum']
  function walk(relative) {
    for (const entry of fs.readdirSync(path.join(sourceDirectory, relative), { withFileTypes: true })) {
      assert.ok(!entry.isSymbolicLink(), 'Candidate source contains unreviewed symlink')
      const file = path.join(relative, entry.name)
      if (entry.isDirectory()) walk(file)
      else if (entry.isFile()) files.push(file)
    }
  }
  walk('internal'); walk('third_party')
  const hash = crypto.createHash('sha256')
  for (const file of files.sort()) hash.update(file + '\0' + sha(fs.readFileSync(path.join(sourceDirectory, file))) + '\n')
  return hash.digest('hex')
}

module.exports = { sixthRecoveryScope, sixthGuardPausedOperation, diagnosticPins, replayPins, validateSixthRecoveryReview, validateSixthRecovery,
  validateSixthDiagnosticEvidence, validateSixthReplayEvidence, verifyReplayInputFiles, candidateSourceTreeHash }