import { useLocalStorageRef } from '~/utils/useLocalStorageRef'

/* ── Types ── */

export type AlertRecipient = 'handler' | 'manager' | 'customer' | 'custom'

export interface EmailSenderConfig {
  senderEmail: string
  senderDisplayName: string
  replyToEmail: string
}

export interface AlertThresholdEntry {
  id: string
  daysBefore: number
  enabled: boolean
}

export interface EscalationTier {
  id: string
  daysOverdue: number
  recipients: AlertRecipient[]
  action: string
}

export interface RenewalAlertConfig {
  enabled: boolean
  thresholds: AlertThresholdEntry[]
}

export interface CancellationAlertConfig {
  enabled: boolean
  recipients: AlertRecipient[]
}

export interface LatePaymentAlertConfig {
  enabled: boolean
  tiers: EscalationTier[]
}

export interface CreditCardExpiryAlertConfig {
  enabled: boolean
  thresholds: AlertThresholdEntry[]
  autoDebitOnly: boolean
}

export interface CustomAlertRule {
  id: string
  alertName: string
  field: string
  operator: 'gte' | 'lte' | 'eq' | 'gt' | 'lt' | 'contains'
  value: string | number | boolean
  recipients: AlertRecipient[]
  enabled: boolean
}

export interface AlertConfig {
  emailSender: EmailSenderConfig
  renewals: RenewalAlertConfig
  cancellations: CancellationAlertConfig
  latePayments: LatePaymentAlertConfig
  creditCardExpiry: CreditCardExpiryAlertConfig
  customRules: CustomAlertRule[]
}

/* ── Defaults ── */

function defaultConfig(): AlertConfig {
  return {
    emailSender: {
      senderEmail: 'alertas@miagencia.com',
      senderDisplayName: 'Segur-OS Alertas',
      replyToEmail: 'soporte@miagencia.com',
    },
    renewals: {
      enabled: true,
      thresholds: [
        { id: 'r90', daysBefore: 90, enabled: true },
        { id: 'r60', daysBefore: 60, enabled: true },
        { id: 'r30', daysBefore: 30, enabled: true },
        { id: 'r15', daysBefore: 15, enabled: true },
      ],
    },
    cancellations: {
      enabled: true,
      recipients: ['handler', 'manager'],
    },
    latePayments: {
      enabled: true,
      tiers: [
        { id: 'lp5', daysOverdue: 5, recipients: ['handler'], action: 'Notify assigned handler' },
        { id: 'lp15', daysOverdue: 15, recipients: ['handler', 'manager'], action: 'Notify handler + manager' },
        { id: 'lp30', daysOverdue: 30, recipients: ['handler', 'manager', 'customer'], action: 'Auto-escalate + notify customer' },
      ],
    },
    creditCardExpiry: {
      enabled: true,
      thresholds: [
        { id: 'cc60', daysBefore: 60, enabled: true },
        { id: 'cc30', daysBefore: 30, enabled: true },
        { id: 'cc15', daysBefore: 15, enabled: true },
      ],
      autoDebitOnly: true,
    },
    customRules: [
      {
        id: 'cr1',
        alertName: 'High-value policy renewal',
        field: 'premium',
        operator: 'gte',
        value: 25000,
        recipients: ['handler', 'manager'],
        enabled: true,
      },
    ],
  }
}

/* ── Composable ── */

let _counter = 100

export function useAlertConfig() {
  const config = useLocalStorageRef<AlertConfig>('policy-ui-alert-config-v1', defaultConfig)

  /* ── Threshold CRUD ── */

  function addThreshold(section: 'renewals' | 'creditCardExpiry', daysBefore: number) {
    const id = `t${++_counter}`
    config.value[section].thresholds.push({ id, daysBefore, enabled: true })
  }

  function removeThreshold(section: 'renewals' | 'creditCardExpiry', id: string) {
    config.value[section].thresholds = config.value[section].thresholds.filter(t => t.id !== id)
  }

  /* ── Late payment tier CRUD ── */

  function addPaymentTier(daysOverdue: number, action: string, recipients: AlertRecipient[]) {
    const id = `lp${++_counter}`
    config.value.latePayments.tiers.push({ id, daysOverdue, recipients, action })
  }

  function removePaymentTier(id: string) {
    config.value.latePayments.tiers = config.value.latePayments.tiers.filter(t => t.id !== id)
  }

  /* ── Custom rule CRUD ── */

  function addCustomRule(rule: Omit<CustomAlertRule, 'id'>) {
    const id = `cr${++_counter}`
    config.value.customRules.push({ ...rule, id })
  }

  function updateCustomRule(id: string, patch: Partial<CustomAlertRule>) {
    const idx = config.value.customRules.findIndex(r => r.id === id)
    if (idx !== -1) {
      config.value.customRules[idx] = { ...config.value.customRules[idx], ...patch }
    }
  }

  function removeCustomRule(id: string) {
    config.value.customRules = config.value.customRules.filter(r => r.id !== id)
  }

  return {
    config,
    addThreshold,
    removeThreshold,
    addPaymentTier,
    removePaymentTier,
    addCustomRule,
    updateCustomRule,
    removeCustomRule,
  }
}