// ── `npm run seed:demo` — the public demo's base (DEMO_MODE.md §7.3) ────────
//
// Run by the wipe workflow inside the app container, after `compose down -v` and
// a fresh `up` have left an empty database with the schema in place:
//
//   docker compose exec app npm run seed:demo -- /app/deploy/demo/seed.json
//
// It writes, from one fixture file:
//   1. the four static logins (§4) — upserted, so a password a visitor somehow
//      changed is back within one cycle and a re-run is harmless;
//   2. the site settings the demo starts from (live, registration disabled, and
//      whatever the fixture adds);
//   3. the seeded content — posts, wiki pages, pages, events — on the first run
//      against a database only, so a re-run never duplicates it;
//   4. each installed module's own rows, through the module's `onDemoSeed` hook
//      (API 1.18.0, DM15): core never writes a module's tables;
//   5. `demo_state` — when the next wipe is due and the published logins, for
//      the banner and the sign-in page (§6).
//
// With the events it also switches on, in the events switchboard, every action
// those events' steps use — otherwise a seeded event cannot run (§7.3).
//
// A string `"$env:NAME"` anywhere in the fixture is replaced with that variable,
// so the rig's sidecar token lives in the host's .env and never in the repo. An
// unset variable fails the run rather than seeding an empty credential.
//
// Refuses to run without DEMO_MODE=true: pointed at a real shard by mistake, it
// would reset four accounts' passwords and flip the site live.

require('dotenv').config()

const fs = require('fs')
const path = require('path')

const { isDemo, DEMO_ACCOUNTS } = require('../src/demo/mode')

const ROLES = ['admin', 'editor', 'moderator', 'player']

const log = require('../src/utils/logger')('seed-demo')

// ── Pure helpers (tested in test/seedDemo.test.js) ─────────────────────────

/** Replace every `"$env:NAME"` string, at any depth. Throws on an unset one. */
function resolveEnv(value, env = process.env, where = 'fixture') {
  if (typeof value === 'string') {
    const m = /^\$env:([A-Z_][A-Z0-9_]*)$/.exec(value)
    if (!m) return value
    const got = env[m[1]]
    if (got === undefined || got === '') throw new Error(`${where}: environment variable ${m[1]} is not set`)
    return got
  }
  if (Array.isArray(value)) return value.map((v, i) => resolveEnv(v, env, `${where}[${i}]`))
  if (value && typeof value === 'object') {
    const out = {}
    for (const [k, v] of Object.entries(value)) out[k] = resolveEnv(v, env, `${where}.${k}`)
    return out
  }
  return value
}

/**
 * When the next wipe is due: the next whole multiple of `everyHours` past
 * midnight UTC, strictly after `now` — the schedule the wipe workflow's cron
 * runs on (DM7: every 2 hours on the hour). The seed runs a minute or two after
 * a wipe starts, so "strictly after" lands on the following slot.
 */
function nextResetAt(now = new Date(), everyHours = 2) {
  const step = everyHours * 60 * 60 * 1000
  const midnight = Date.UTC(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate())
  const slots = Math.floor((now.getTime() - midnight) / step) + 1
  return new Date(midnight + slots * step)
}

/** Check the fixture's shape before anything is written. Returns a list of problems. */
function checkFixture(fixture) {
  const problems = []
  if (!fixture || typeof fixture !== 'object' || Array.isArray(fixture)) return ['the fixture must be a JSON object']
  const accounts = fixture.accounts || {}
  for (const name of DEMO_ACCOUNTS) {
    const a = accounts[name]
    if (!a) {
      problems.push(`accounts.${name} is missing`)
      continue
    }
    if (typeof a.password !== 'string' || a.password.length < 8) {
      problems.push(`accounts.${name}.password must be a string of at least 8 characters`)
    }
    if (!ROLES.includes(a.role)) problems.push(`accounts.${name}.role must be one of ${ROLES.join(', ')}`)
  }
  for (const name of Object.keys(accounts)) {
    if (!DEMO_ACCOUNTS.includes(name)) {
      problems.push(`accounts.${name} is not a demo account (the lock only knows ${DEMO_ACCOUNTS.join(', ')})`)
    }
  }
  if (fixture.settings !== undefined) {
    if (!fixture.settings || typeof fixture.settings !== 'object' || Array.isArray(fixture.settings)) {
      problems.push('settings must be an object')
    } else if ('demo_state' in fixture.settings) {
      problems.push('settings.demo_state is written by the seed itself')
    }
  }
  for (const key of ['posts', 'wiki', 'pages', 'events']) {
    const list = fixture.content?.[key]
    if (list !== undefined && !Array.isArray(list)) problems.push(`content.${key} must be an array`)
  }
  if (fixture.modules !== undefined && (typeof fixture.modules !== 'object' || Array.isArray(fixture.modules))) {
    problems.push('modules must be an object keyed by module id')
  }
  return problems
}

/**
 * Every action a seeded event's steps use, once each, in first-use order.
 *
 * A fresh database has no switchboard rows, so every `change` and `irreversible`
 * action starts disabled (EVENTS.md §K) — and a seeded event that answers "not
 * enabled on this deployment" when a visitor runs it is a showcase that does not
 * show (step-5 walk, W1). The seed switches on exactly these and nothing else.
 */
function eventActionIds(events = []) {
  const ids = []
  for (const e of events) {
    for (const phase of e?.spec?.phases || []) {
      for (const step of phase?.steps || []) {
        if (step?.actionId && !ids.includes(step.actionId)) ids.push(step.actionId)
      }
    }
  }
  return ids
}

// ── The run ────────────────────────────────────────────────────────────────

/* eslint-disable global-require */
async function upsertAccounts(fixture) {
  const users = require('../src/model/users/users.model')
  const ids = {}
  for (const username of DEMO_ACCOUNTS) {
    const { password, role } = fixture.accounts[username]
    const existing = await users.getRawByUsername(username)
    let id
    if (existing) {
      id = existing.id
      // A password change bumps the session cutoff, which signs every visitor out
      // of this account — the right outcome at a wipe, and on a fresh database
      // (the normal case) there is nobody to sign out.
      await users.update(id, { password, role, status: 'active', emailVerified: true })
      await users.disableTotp(id)
    } else {
      const created = await users.createUser({ username, password, role, status: 'active', emailVerified: true })
      id = created.id
    }
    ids[username] = id
    log.info(`account ${username} (${role}) ready`, { id })
  }
  return ids
}

async function writeSettings(fixture) {
  const settings = require('../src/model/settings/settings.model')
  await settings.setMany({
    site_mode: 'live',
    site_mode_changed_at: new Date().toISOString(),
    site_mode_changed_by: 'seed:demo',
    // §4: registration is closed, and the route is locked too (DM16).
    [settings.REGISTRATION_KEY]: 'disabled',
    ...(fixture.settings || {}),
  })
}

async function writeContent(fixture, authorId) {
  const content = fixture.content || {}
  const posts = require('../src/model/posts/posts.model')
  const wiki = require('../src/model/wiki/wiki.model')
  const pages = require('../src/model/pages/pages.model')
  const events = require('../src/model/events/eventDefinitions.model')

  for (const p of content.posts || []) {
    const category = posts.toDbCategory(p.category || 'news')
    if (!category) throw new Error(`post "${p.title}": unknown category "${p.category}"`)
    await posts.create({ ...p, category, published: p.published !== false, author_id: authorId })
  }
  for (const w of content.wiki || []) {
    const category = w.category ? await wiki.getCategoryBySlug(w.category) : null
    if (w.category && !category) throw new Error(`wiki "${w.slug}": unknown category "${w.category}"`)
    await wiki.create({ ...w, categoryId: category ? category.id : null, updatedBy: authorId })
  }
  for (const pg of content.pages || []) {
    await pages.create(pg, authorId)
  }
  for (const e of content.events || []) {
    const { publish, ...input } = e
    const made = await events.create(input, authorId, { role: 'admin' })
    if (!made.ok) throw new Error(`event "${input.name || input.title}": ${(made.errors || []).join('; ')}`)
    if (publish) {
      const pub = await events.publish(made.id, authorId)
      if (!pub.ok) throw new Error(`event "${input.name || input.title}" did not publish: ${(pub.errors || []).join('; ')}`)
    }
  }
  // Uncapped, like a switch an admin flips without filling the cap boxes: the
  // deny list (DM11) is what keeps a visitor's own command step harmless, and the
  // wipe takes the row away with the rest of the database.
  const actionSettings = require('../src/model/events/eventActionSettings.db')
  const enabled = eventActionIds(content.events)
  for (const actionId of enabled) await actionSettings.put(actionId, { enabled: true, caps: {} }, authorId)
  log.info('content written', {
    posts: (content.posts || []).length,
    wiki: (content.wiki || []).length,
    pages: (content.pages || []).length,
    events: (content.events || []).length,
    actionsEnabled: enabled,
  })
}

async function seedModules(fixture, accounts) {
  const modules = require('../src/modules/loader')
  const hooks = modules.demoSeedHooks()
  const wanted = fixture.modules || {}
  for (const id of Object.keys(wanted)) {
    if (!hooks.some((h) => h.id === id)) {
      throw new Error(`modules.${id}: no installed module "${id}" takes a demo seed (onDemoSeed)`)
    }
  }
  for (const { id, hook } of hooks) {
    if (wanted[id] === undefined) continue
    // The module gets its part of the fixture and the demo accounts' ids, so it
    // can link one of them to a game identity without reading core's users table.
    await hook(wanted[id], { accounts: { ...accounts } })
    log.info(`module ${id} seeded`)
  }
}

async function writeState(fixture, now = new Date()) {
  const settings = require('../src/model/settings/settings.model')
  const everyHours = Number(process.env.DEMO_RESET_EVERY_HOURS) || 2
  const logins = DEMO_ACCOUNTS
    .filter((name) => fixture.accounts[name].published !== false)
    .map((name) => ({ username: name, password: fixture.accounts[name].password, role: fixture.accounts[name].role }))
  const state = { resetsAt: nextResetAt(now, everyHours).toISOString(), logins }
  await settings.set(settings.DEMO_STATE_KEY, JSON.stringify(state))
  log.info('demo state stamped', { resetsAt: state.resetsAt, logins: logins.length })
}

async function run(file) {
  if (!isDemo()) throw new Error('seed:demo runs only with DEMO_MODE=true')
  if (!file) throw new Error('usage: npm run seed:demo -- <fixture.json>  (or set DEMO_SEED_FILE)')

  const fixture = resolveEnv(JSON.parse(fs.readFileSync(path.resolve(file), 'utf8')))
  const problems = checkFixture(fixture)
  if (problems.length) throw new Error(`the fixture has problems:\n  - ${problems.join('\n  - ')}`)

  // The app itself, without listening: this is what loads the installed modules
  // (and core's registries, which an event definition is validated against)
  // exactly as the server does. Nothing here calls onBoot, so no module starts
  // its workers in this process.
  require('../src/app')
  const settings = require('../src/model/settings/settings.model')

  const firstRun = !(await settings.get(settings.DEMO_STATE_KEY))
  const accounts = await upsertAccounts(fixture)
  await writeSettings(fixture)
  if (firstRun) await writeContent(fixture, accounts['demo-admin'])
  else log.info('content already seeded on this database; left as is')
  await seedModules(fixture, accounts)
  await writeState(fixture)
}
/* eslint-enable global-require */

if (require.main === module) {
  ;(async () => {
    const { close } = require('../src/utils/db') // eslint-disable-line global-require
    try {
      await run(process.argv[2] || process.env.DEMO_SEED_FILE)
      log.info('demo seeded')
    } catch (err) {
      log.error(`seed:demo failed: ${err.message}`)
      process.exitCode = 1
    } finally {
      await close()
    }
  })()
}

module.exports = { resolveEnv, nextResetAt, checkFixture, eventActionIds, run }