// ── Admin: events ──────────────────────────────────────────────────────────
//
// EVENTS.md § API surface, Phase 1. Definitions CRUD, publish, archive, the
// action catalog and the run reads.
//
// This file reads ids out of URLs and shapes responses; it validates nothing.
// Every decision lives in `model/events/*.model.js` and in `events/spec.js`, so
// a definition arriving from a future import or a restore gets the same answer
// this screen does.
//
// **Phase 3 added the live run controls** at the bottom of this file: pause,
// resume, cancel, and a step's confirm, skip and retry. What is still absent is
// `advance`, `cleanup` and the action switchboard — `advance` has no honest
// meaning until Phase 5 gives a phase an advance condition, `cleanup` has no
// ledger to work over until Phase 8, and the switchboard is Phase 6's. Each of
// them is absent rather than stubbed, for the reason the whole set was in Phase
// 1: a control that returns 200 and does nothing is worse than one that is not
// there.

const registries = require('../../../modules/registries')
const spec = require('../../../events/spec')
const conditionGrammar = require('../../../engagement/conditions')
const definitionsDb = require('../../../model/events/eventDefinitions.db')
const definitions = require('../../../model/events/eventDefinitions.model')
const versionsDb = require('../../../model/events/eventVersions.db')
const seriesDb = require('../../../model/events/eventSeries.db')
const series = require('../../../model/events/eventSeries.model')
const calendarModel = require('../../../model/events/eventCalendar.model')
const eventRunner = require('../../../utils/eventRunner')
const runsDb = require('../../../model/events/eventRuns.db')
const runs = require('../../../model/events/eventRuns.model')
const controls = require('../../../model/events/eventRunControls.model')
const logDb = require('../../../model/events/eventRunLog.db')
const activity = require('../../../model/activity/activity.model')

const asId = (raw) => {
  const n = Number(raw)
  return Number.isInteger(n) && n > 0 ? n : null
}

/**
 * The shape a definition takes on the wire.
 *
 * Explicit rather than the row, like every other admin surface here: the row
 * carries `created_by`, `updated_by` and the joined series columns, and a
 * response that spreads it is a response that gains a column the day somebody
 * adds one.
 */
const shapeDefinition = (d) => ({
  id: d.id,
  title: d.title,
  slug: d.slug,
  summary: d.summary,
  body: d.body,
  imageUrl: d.image_url,
  ownerModule: d.owner_module,
  state: d.state,
  currentVersionId: d.current_version_id,
  currentVersion: d.current_version,
  seriesId: d.series_id,
  seriesName: d.series_name,
  seriesOrder: d.series_order,
  concurrencyKey: d.concurrency_key,
  graceSeconds: d.grace_seconds,
  timezone: d.timezone,
  spec: d.spec,
  createdAt: d.created_at,
  updatedAt: d.updated_at,
})

const shapeRun = (r) => ({
  id: r.id,
  definitionId: r.definition_id,
  definitionTitle: r.definition_title,
  definitionSlug: r.definition_slug,
  versionId: r.version_id,
  version: r.version_number,
  scope: r.scope,
  status: r.status,
  health: r.health,
  cleanupStatus: r.cleanup_status,
  currentPhase: r.current_phase,
  scheduledFor: r.scheduled_for,
  timezone: r.timezone,
  concurrencyKey: r.concurrency_key,
  params: r.params,
  rehearsal: r.rehearsal,
  startedAt: r.started_at,
  endedAt: r.ended_at,
  lastError: r.last_error,
  createdAt: r.created_at,
  // How many steps are parked on a human. Derived, not a column, and surfaced on
  // the LIST as well as the console because a cue nobody notices is a run that
  // never advances while looking perfectly healthy from the outside.
  waitingSteps: Number(r.waiting_steps || 0),
})

const shapeStep = (s) => ({
  id: s.id,
  runId: s.run_id,
  phase: s.phase,
  seq: s.seq,
  actionId: s.action_id,
  params: s.params,
  actionVersion: s.action_version,
  status: s.status,
  // `running` with no lease is a parked step (§E) — waiting on a human, with
  // nothing holding it. The console has to tell that apart from a step some
  // process is mid-dispatch on, and it must not do so by being shown the lease:
  // one derived boolean rather than `claimed_by` and `claim_expires_at`, which
  // are the runner's business and would invite a UI that reasoned about leases.
  parked: s.status === 'running' && !s.claim_expires_at,
  dueAt: s.due_at,
  attempts: s.attempts,
  onFailure: s.on_failure,
  idempotencyKey: s.idempotency_key,
  lastError: s.last_error,
  startedAt: s.started_at,
  finishedAt: s.finished_at,
})

/** GET /api/v1/admin/events */
exports.list = async (req, res) => {
  const state = ['draft', 'ready', 'archived'].includes(req.query.state) ? req.query.state : null
  const rows = await definitionsDb.list({ state })
  res.json({ events: rows.map(shapeDefinition) })
}

/**
 * GET /api/v1/admin/events/catalog
 *
 * The registered actions, their param schemas, their risk classes and the
 * vocabularies over both — served from the registries, so there is no table
 * behind it and a module that was uninstalled simply stops appearing. Same
 * argument the engagement trigger catalog makes: the editor offers exactly the
 * set the save path checks against, so the two cannot drift.
 *
 * Budget dimensions are absent, and that is Phase 1 being honest rather than an
 * omission: `registerEventBudgets` is Phase 7's and nothing declares one yet.
 */
exports.catalog = (_req, res) => {
  res.json({
    actions: registries.allEventActions(),
    risks: registries.ACTION_RISKS,
    reversible: registries.ACTION_REVERSIBLE,
    paramTypes: registries.ACTION_PARAM_TYPES,
    onFailure: spec.ON_FAILURE,
    onFailureByRisk: spec.ON_FAILURE_BY_RISK,
    scheduleKinds: spec.SCHEDULE_KINDS,
    // **The trigger catalog is served here too, and not borrowed from
    // `/admin/engagement/triggers`** (Phase 5). §C's claim is that the trigger
    // catalog a module already ships IS the catalog of things that can advance a
    // phase — so it is the same registry, read twice. What differs is who may
    // read it: the engagement route is `adminOnly`, and event definitions are
    // authored by `admin` AND `editor`. Pointing this editor at that route would
    // have left an editor writing a trigger id from memory into a field the save
    // path then refused.
    //
    // Each declaration is reduced to what the gate form needs — id, label and
    // the variables a `where` may name. Everything else on a trigger (its
    // audience, its ceiling, its subject key) is about who gets MAILED, which is
    // a different question and not this screen's.
    triggers: registries.allTriggers().map((t) => ({
      id: t.id,
      label: t.label,
      description: t.description,
      owner: t.owner,
      variables: (t.variables || []).map((v) => ({
        name: v.name,
        type: v.type,
        required: v.required,
        description: v.description,
      })),
    })),
    operators: conditionGrammar.vocabulary(),
    advanceKinds: spec.ADVANCE_KINDS,
    limits: {
      maxPhases: spec.MAX_PHASES,
      maxStepsPerPhase: spec.MAX_STEPS_PER_PHASE,
      maxSteps: spec.MAX_STEPS,
      defaultBudgetMs: registries.DEFAULT_BUDGET_MS,
      maxAdvanceCount: spec.MAX_ADVANCE_COUNT,
      maxAfterSeconds: spec.MAX_AFTER_SECONDS,
    },
  })
}

const shapeSeries = (s) => ({
  id: s.id,
  name: s.name,
  slug: s.slug,
  description: s.description,
  ordering: s.ordering,
  definitionCount: Number(s.definition_count || 0),
})

/** GET /api/v1/admin/events/series */
exports.listSeries = async (_req, res) => {
  const rows = await seriesDb.list()
  res.json({ series: rows.map(shapeSeries) })
}

/** POST /api/v1/admin/events/series */
exports.createSeries = async (req, res) => {
  const result = await series.create(req.body, req.user?.id)
  if (!result.ok) return res.status(result.status).json({ errors: result.errors })
  await activity.log({
    req,
    action: 'event.series.created',
    detail: { id: result.series.id, name: result.series.name },
  })
  res.status(201).json({ series: shapeSeries(result.series) })
}

/** PUT /api/v1/admin/events/series/:seriesId */
exports.updateSeries = async (req, res) => {
  const id = asId(req.params.seriesId)
  if (!id) return res.status(404).json({ error: 'no such series' })
  const result = await series.update(id, req.body, req.user?.id)
  if (!result.ok) return res.status(result.status).json({ errors: result.errors })
  await activity.log({ req, action: 'event.series.updated', detail: { id, name: result.series.name } })
  res.json({ series: shapeSeries(result.series) })
}

/**
 * DELETE /api/v1/admin/events/series/:seriesId
 *
 * `detached` is in the response because the delete is not confined to the row:
 * `series_id` is `ON DELETE SET NULL`, so definitions that belonged to the arc
 * survive it without one. Saying how many is the difference between an operator
 * knowing and an operator finding out.
 */
exports.deleteSeries = async (req, res) => {
  const id = asId(req.params.seriesId)
  if (!id) return res.status(404).json({ error: 'no such series' })
  const result = await series.remove(id)
  if (!result.ok) return res.status(result.status).json({ errors: result.errors })
  await activity.log({ req, action: 'event.series.deleted', detail: { id, detached: result.detached } })
  res.json({ ok: true, detached: result.detached })
}

/**
 * GET /api/v1/admin/events/calendar
 *
 * `from` and `to` are UTC instants and the caller supplies both: a month grid
 * knows its own boundaries in the viewer's zone, and having the server guess
 * them would be the server guessing the viewer's zone.
 */
exports.calendar = async (req, res) => {
  const result = await calendarModel.calendar({
    from: req.query.from,
    to: req.query.to,
    status: req.query.status || null,
    scope: req.query.scope || null,
    seriesId: asId(req.query.seriesId),
    horizonDays: eventRunner.HORIZON_DAYS,
  })
  if (!result.ok) return res.status(result.status).json({ errors: result.errors })
  res.json({
    window: result.window,
    horizon: result.horizon,
    horizonDays: eventRunner.HORIZON_DAYS,
    entries: result.entries,
    truncated: result.truncated,
  })
}

/** GET /api/v1/admin/events/runs */
exports.listRuns = async (req, res) => {
  const rows = await runsDb.list({
    definitionId: asId(req.query.definitionId),
    status: req.query.status || null,
    limit: req.query.limit,
  })
  res.json({ runs: rows.map(shapeRun) })
}

/** GET /api/v1/admin/events/runs/:runId */
exports.getRun = async (req, res) => {
  const runId = asId(req.params.runId)
  if (!runId) return res.status(400).json({ error: 'bad run id' })
  const found = await runs.detail(runId)
  if (!found) return res.status(404).json({ error: 'no such run' })
  return res.json({
    run: shapeRun(found.run),
    steps: found.steps.map(shapeStep),
    counts: found.counts,
    // Already rendered in the condition builder's own words (Phase 5). See
    // `eventRuns.model.detail` for why the sentence is built here and not in
    // the browser.
    gates: found.gates,
  })
}

/** GET /api/v1/admin/events/runs/:runId/log */
exports.getRunLog = async (req, res) => {
  const runId = asId(req.params.runId)
  if (!runId) return res.status(400).json({ error: 'bad run id' })
  const run = await runsDb.getById(runId)
  if (!run) return res.status(404).json({ error: 'no such run' })
  const lines = await logDb.listForRun(runId, { limit: req.query.limit })
  return res.json({
    log: lines.map((l) => ({
      id: l.id,
      stepId: l.step_id,
      kind: l.kind,
      phase: l.phase,
      detail: l.detail,
      at: l.at,
    })),
    kinds: logDb.KINDS,
  })
}

/** GET /api/v1/admin/events/:id */
exports.get = async (req, res) => {
  const id = asId(req.params.id)
  if (!id) return res.status(400).json({ error: 'bad event id' })
  const row = await definitionsDb.getById(id)
  if (!row) return res.status(404).json({ error: 'no such event definition' })
  return res.json({ event: shapeDefinition(row) })
}

/** GET /api/v1/admin/events/:id/versions */
exports.listVersions = async (req, res) => {
  const id = asId(req.params.id)
  if (!id) return res.status(400).json({ error: 'bad event id' })
  const row = await definitionsDb.getById(id)
  if (!row) return res.status(404).json({ error: 'no such event definition' })
  const rows = await versionsDb.listForDefinition(id)
  return res.json({
    versions: rows.map((v) => ({
      id: v.id,
      version: v.version,
      publishedAt: v.published_at,
      publishedBy: v.published_by,
      publishedByUsername: v.published_by_username,
      current: v.id === row.current_version_id,
    })),
  })
}

/** POST /api/v1/admin/events */
exports.create = async (req, res) => {
  const result = await definitions.create(req.body, req.user.id)
  if (!result.ok) return res.status(result.status || 400).json({ errors: result.errors })
  await activity.log({
    req,
    action: 'event.definition.created',
    detail: { id: result.id, title: result.definition.title },
  })
  return res.status(201).json({ event: shapeDefinition(result.definition) })
}

/** PUT /api/v1/admin/events/:id */
exports.update = async (req, res) => {
  const id = asId(req.params.id)
  if (!id) return res.status(400).json({ error: 'bad event id' })
  const result = await definitions.save(id, req.body, req.user.id)
  if (!result.ok) return res.status(result.status || 400).json({ errors: result.errors })
  await activity.log({
    req,
    action: 'event.definition.updated',
    detail: { id, title: result.definition.title },
  })
  return res.json({ event: shapeDefinition(result.definition) })
}

/** POST /api/v1/admin/events/:id/publish */
exports.publish = async (req, res) => {
  const id = asId(req.params.id)
  if (!id) return res.status(400).json({ error: 'bad event id' })
  const result = await definitions.publish(id, req.user.id)
  if (!result.ok) return res.status(result.status || 400).json({ errors: result.errors })
  await activity.log({
    req,
    action: 'event.definition.published',
    detail: { id, version: result.version, versionId: result.versionId, repinned: result.repinned },
  })
  return res.json({
    event: shapeDefinition(result.definition),
    version: result.version,
    versionId: result.versionId,
    // How many already-materialised occurrences moved to this version. The
    // screen says so, because "my fix did not reach next Friday" is otherwise
    // found out on Friday.
    repinned: result.repinned,
  })
}

/** DELETE /api/v1/admin/events/:id — archive, never a hard delete */
exports.archive = async (req, res) => {
  const id = asId(req.params.id)
  if (!id) return res.status(400).json({ error: 'bad event id' })
  const result = await definitions.archive(id, req.user.id)
  if (!result.ok) return res.status(result.status || 400).json({ errors: result.errors })
  await activity.log({ req, action: 'event.definition.archived', detail: { id } })
  return res.json({ event: shapeDefinition(result.definition) })
}

/**
 * POST /api/v1/admin/events/:id/runs
 *
 * Creates the occurrence. It stays `scheduled` until Phase 2's runner exists,
 * and the response says so through `pending: true` rather than by pretending
 * something started.
 */
exports.startRun = async (req, res) => {
  const id = asId(req.params.id)
  if (!id) return res.status(400).json({ error: 'bad event id' })
  const result = await runs.create(
    id,
    {
      scope: req.body?.scope,
      scheduledFor: req.body?.scheduledFor,
      rehearsal: Boolean(req.body?.rehearsal),
      params: req.body?.params ?? null,
    },
    req.user.id,
  )
  if (!result.ok) return res.status(result.status || 400).json({ errors: result.errors })
  if (result.created) {
    await activity.log({
      req,
      action: 'event.run.created',
      detail: {
        definitionId: id,
        runId: result.run.id,
        rehearsal: Boolean(req.body?.rehearsal),
      },
    })
  }
  return res.status(result.created ? 201 : 200).json({
    run: shapeRun(result.run),
    created: result.created,
  })
}

// ── Phase 3: the live run controls ─────────────────────────────────────────
//
// Six handlers, and each is the same four lines: read the ids out of the URL,
// hand off to `eventRunControls`, log the manual transition to `activity_log`,
// answer with the row. Every guard is in the model, where a control invoked from
// anywhere else gets the same answer — which is the same division this file has
// had since Phase 1.
//
// **The audit is written in two places on purpose, and they are not redundant.**
// `event_run_log` is the run's own diagnostic record: queryable by phase and by
// step, and it is what the console renders. `activity_log` is the deployment's
// record of what staff did, and it is where "who cancelled the invasion" is
// looked up months later by somebody who is not looking at that run. §J names
// both.

/** POST /api/v1/admin/events/runs/:runId/pause */
exports.pauseRun = async (req, res) => {
  const runId = asId(req.params.runId)
  if (!runId) return res.status(400).json({ error: 'bad run id' })
  const result = await controls.pause(runId, { reason: req.body?.reason }, req.user.id)
  if (!result.ok) return res.status(result.status || 409).json({ errors: result.errors })
  await activity.log({ req, action: 'event.run.paused', detail: { runId, reason: req.body?.reason || null } })
  return res.json({ run: shapeRun(result.run) })
}

/** POST /api/v1/admin/events/runs/:runId/resume */
exports.resumeRun = async (req, res) => {
  const runId = asId(req.params.runId)
  if (!runId) return res.status(400).json({ error: 'bad run id' })
  const result = await controls.resume(runId, {}, req.user.id)
  if (!result.ok) return res.status(result.status || 409).json({ errors: result.errors })
  await activity.log({ req, action: 'event.run.resumed', detail: { runId } })
  return res.json({ run: shapeRun(result.run) })
}

/** POST /api/v1/admin/events/runs/:runId/advance */
exports.advanceRunPhase = async (req, res) => {
  const runId = asId(req.params.runId)
  if (!runId) return res.status(400).json({ error: 'bad run id' })
  const result = await controls.advancePhase(runId, { reason: req.body?.reason }, req.user.id)
  if (!result.ok) return res.status(result.status || 409).json({ errors: result.errors })
  await activity.log({
    req,
    action: 'event.run.advanced',
    detail: { runId, phase: result.phase, reason: req.body?.reason || null },
  })
  return res.json({ run: shapeRun(result.run), phase: result.phase })
}

/** POST /api/v1/admin/events/runs/:runId/cancel */
exports.cancelRun = async (req, res) => {
  const runId = asId(req.params.runId)
  if (!runId) return res.status(400).json({ error: 'bad run id' })
  const result = await controls.cancel(runId, { reason: req.body?.reason }, req.user.id)
  if (!result.ok) return res.status(result.status || 409).json({ errors: result.errors })
  await activity.log({
    req,
    action: 'event.run.cancelled',
    detail: { runId, reason: req.body?.reason || null, cancelledSteps: result.cancelledSteps },
  })
  return res.json({ run: shapeRun(result.run), cancelledSteps: result.cancelledSteps })
}

/** POST /api/v1/admin/events/runs/:runId/steps/:stepId/confirm */
exports.confirmStep = async (req, res) => {
  const runId = asId(req.params.runId)
  const stepId = asId(req.params.stepId)
  if (!runId || !stepId) return res.status(400).json({ error: 'bad run or step id' })
  const result = await controls.confirmStep(runId, stepId, { note: req.body?.note }, req.user.id)
  if (!result.ok) return res.status(result.status || 409).json({ errors: result.errors })
  await activity.log({ req, action: 'event.step.confirmed', detail: { runId, stepId, action: result.step.action_id } })
  return res.json({ step: shapeStep(result.step) })
}

/** POST /api/v1/admin/events/runs/:runId/steps/:stepId/skip */
exports.skipStep = async (req, res) => {
  const runId = asId(req.params.runId)
  const stepId = asId(req.params.stepId)
  if (!runId || !stepId) return res.status(400).json({ error: 'bad run or step id' })
  const result = await controls.skipStep(runId, stepId, { reason: req.body?.reason }, req.user.id)
  if (!result.ok) return res.status(result.status || 409).json({ errors: result.errors })
  await activity.log({
    req,
    action: 'event.step.skipped',
    detail: { runId, stepId, action: result.step.action_id, reason: req.body?.reason || null },
  })
  return res.json({ step: shapeStep(result.step) })
}

/** POST /api/v1/admin/events/runs/:runId/steps/:stepId/retry */
exports.retryStep = async (req, res) => {
  const runId = asId(req.params.runId)
  const stepId = asId(req.params.stepId)
  if (!runId || !stepId) return res.status(400).json({ error: 'bad run or step id' })
  const result = await controls.retryStep(runId, stepId, {}, req.user.id)
  if (!result.ok) return res.status(result.status || 409).json({ errors: result.errors })
  await activity.log({ req, action: 'event.step.retried', detail: { runId, stepId, action: result.step.action_id } })
  return res.json({ step: shapeStep(result.step), run: shapeRun(result.run), resumed: result.resumed })
}