import { randomBytes } from 'node:crypto'
import { uuidv7 } from '@sims/domain'
import { createStaff } from './auth'
import { writeAudit } from './audit'
import type { DB } from './db'
import { createModule } from './repos-modules'
import { SCHEDULE_DEFAULTS, type ScheduleRuleKind } from './repos-reminders'

/** First-boot seed: owner login, company settings placeholders, GST18 tax class. */

const OWNER_EMAIL = 'admin@tecnostac.com'

const SETTING_DEFAULTS: Record<string, string> = {
  'company.name': 'Tecnostac',
  'company.address': '',
  'company.gstin': '',
  'company.state_code': '32', // Kerala — founder to confirm
  'company.phone': '',
  'company.email': OWNER_EMAIL,
  'company.bank': '',
}

const INTERACTION_TYPES: [string, string][] = [
  ['call', 'Call'], ['site_visit', 'Site visit'], ['training', 'Training'],
  ['courtesy_meeting', 'Courtesy meeting'], ['committee_meeting', 'Committee meeting'],
  ['demo', 'Demo'], ['complaint', 'Complaint'],
]

const REMINDER_SETTINGS: Record<string, string> = {
  'reminders.overdue_days': '7',
  'reminders.renewal_days': '15',
}

export function seedIfEmpty(db: DB): void {
  const staff = db.prepare(`SELECT COUNT(*) AS n FROM staff_user`).get() as { n: number }
  if (staff.n === 0) {
    // 9 random bytes → 12 base64url chars; printed exactly once, never stored in clear.
    const password = randomBytes(9).toString('base64url')
    createStaff(db, { email: OWNER_EMAIL, displayName: 'Owner', role: 'owner', password })
    console.log(`SiMS HQ first boot — owner ${OWNER_EMAIL} password: ${password} (change after first login)`)
  }
  const insert = db.prepare(
    // Portability quirk: ON CONFLICT upsert is SQLite/Postgres dialect (standard SQL has MERGE).
    `INSERT INTO setting (key, value) VALUES (?, ?) ON CONFLICT (key) DO NOTHING`,
  )
  let seededSettings = 0
  for (const [key, value] of Object.entries(SETTING_DEFAULTS)) {
    seededSettings += insert.run(key, value).changes
  }
  if (seededSettings > 0) {
    writeAudit(db, 'system', 'seed', 'setting', 'company.*', undefined, SETTING_DEFAULTS)
  }
  const gst = db.prepare(`SELECT COUNT(*) AS n FROM tax_class WHERE class_code='GST18'`).get() as { n: number }
  if (gst.n === 0) {
    db.prepare(
      `INSERT INTO tax_class (class_code, rate_pct_bp, effective_from) VALUES ('GST18', 1800, '2017-07-01')`,
    ).run()
    writeAudit(db, 'system', 'seed', 'tax_class', 'GST18', undefined, { ratePctBp: 1800, effectiveFrom: '2017-07-01' })
  }

  const typeInsert = db.prepare(
    // Portability quirk: ON CONFLICT upsert is SQLite/Postgres dialect (standard SQL has MERGE).
    `INSERT INTO interaction_type (code, label) VALUES (?, ?) ON CONFLICT (code) DO NOTHING`,
  )
  let seededTypes = 0
  for (const [code, label] of INTERACTION_TYPES) seededTypes += typeInsert.run(code, label).changes
  if (seededTypes > 0) writeAudit(db, 'system', 'seed', 'interaction_type', '*', undefined, { count: seededTypes })

  let seededReminderSettings = 0
  for (const [key, value] of Object.entries(REMINDER_SETTINGS)) seededReminderSettings += insert.run(key, value).changes
  if (seededReminderSettings > 0) writeAudit(db, 'system', 'seed', 'setting', 'reminders.*', undefined, REMINDER_SETTINGS)

  // Dated reminder schedules (rule 3 / D-REMIND): one open-ended row per rule kind,
  // matching the code-constant fallback. A cadence change is a NEW dated row, not an edit.
  const scheduleKinds: ScheduleRuleKind[] = ['quote_followup', 'invoice_overdue']
  for (const ruleKind of scheduleKinds) {
    const have = db.prepare(`SELECT COUNT(*) AS n FROM reminder_schedule WHERE rule_kind=?`).get(ruleKind) as { n: number }
    if (have.n > 0) continue
    const d = SCHEDULE_DEFAULTS[ruleKind]
    const id = uuidv7()
    const effectiveFrom = '2020-01-01' // predates all HQ data — active for every business date
    db.transaction(() => {
      db.prepare(
        `INSERT INTO reminder_schedule (id, rule_kind, effective_from, effective_to, day_offsets, subject, body)
         VALUES (?, ?, ?, NULL, ?, ?, ?)`,
      ).run(id, ruleKind, effectiveFrom, d.dayOffsets.join(','), d.subject, d.body)
      writeAudit(db, 'system', 'seed', 'reminder_schedule', id, undefined, {
        ruleKind, effectiveFrom, dayOffsets: d.dayOffsets.join(','),
      })
    })()
  }

  const amc = db.prepare(`SELECT COUNT(*) AS n FROM module WHERE code='AMC'`).get() as { n: number }
  if (amc.n === 0) {
    // The AMC/renewal invoice line hangs off a real module so it flows through
    // createDraft → computeBill unchanged. SAC 998719 (maintenance/repair) — CA to confirm.
    createModule(db, 'system', {
      code: 'AMC', name: 'Annual Maintenance Contract', sac: '998719',
      allowedKinds: ['yearly', 'one_time'],
    })
  }
}