'use client'

import { useCallback, useEffect, useState } from 'react'
import { useLocale, useTranslations } from 'next-intl'
import { useRouter, useSearchParams } from 'next/navigation'
import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card'
import { Button } from '@/components/ui/button'
import { Badge } from '@/components/ui/badge'
import { Switch } from '@/components/ui/switch'
import { Input } from '@/components/ui/input'
import { Label } from '@/components/ui/label'
import { Skeleton } from '@/components/ui/skeleton'
import { useToast } from '@/components/ui/use-toast'
import { useFormat } from '@/lib/hooks/use-format'
import { failureDescription } from '@/lib/browser/action-failure'
import type { ErrorLocale } from '@/lib/errors/get-error-message'
import { KeyRound, Link2, Loader2, RefreshCw, ShoppingCart, Unlink } from 'lucide-react'
import { PaymentMethodMappingForm } from '@/components/orders/PaymentMethodMappingForm'
import {
  wooRequest,
  syncSummary,
  WOO_CONNECT_TIMEOUT_MS,
  WOO_SYNC_TIMEOUT_MS,
  type WooSyncPayload,
} from '../lib/settings-actions'
import type { WooCommerceConnectionStatus, WooCommerceStatusResponse } from '../types'

const STATUS_VARIANT: Record<
  WooCommerceConnectionStatus['status'],
  'success' | 'secondary' | 'destructive' | 'warning'
> = {
  active: 'success',
  pending: 'secondary',
  revoked: 'warning',
  error: 'destructive',
}

/** Client twin of wooStoreScope(): store identity used by the mapping table. */
function storeScopeOf(storeUrl: string): string {
  return storeUrl.replace(/^https:\/\//, '')
}

export default function WooCommerceSettingsPanel() {
  const t = useTranslations('woocommerce')
  const tCommon = useTranslations('common')
  const locale = useLocale() as ErrorLocale
  const { toast } = useToast()
  const router = useRouter()
  const searchParams = useSearchParams()
  const { formatDateLong } = useFormat()

  const [loading, setLoading] = useState(true)
  const [loadFailed, setLoadFailed] = useState(false)
  const [configured, setConfigured] = useState(false)
  const [connections, setConnections] = useState<WooCommerceConnectionStatus[]>([])
  const [storeUrl, setStoreUrl] = useState('')
  const [manualMode, setManualMode] = useState(false)
  const [consumerKey, setConsumerKey] = useState('')
  const [consumerSecret, setConsumerSecret] = useState('')
  const [connecting, setConnecting] = useState(false)
  // Per-store busy/confirm states, keyed by connection id.
  const [busyId, setBusyId] = useState<string | null>(null)
  const [confirmDisconnectId, setConfirmDisconnectId] = useState<string | null>(null)

  const failureCopy = { timeout: t('action_timeout'), network: t('action_network') }

  const loadStatus = useCallback(async () => {
    // A failed status read must never render as "not configured" (see the
    // Stripe panel: that copy sends the user to an administrator for nothing).
    const result = await wooRequest<WooCommerceStatusResponse>({
      url: '/api/extensions/ext/woocommerce/status',
      method: 'GET',
      locale,
    })
    setLoading(false)
    if (!result.ok || !result.data) {
      setLoadFailed(true)
      return
    }
    setLoadFailed(false)
    setConfigured(result.data.configured)
    // Older payload shape fallback: a single `connection`.
    setConnections(
      result.data.connections ?? (result.data.connection ? [result.data.connection] : []),
    )
  }, [locale])

  useEffect(() => {
    void loadStatus()
  }, [loadStatus])

  function retryLoadStatus() {
    setLoading(true)
    void loadStatus()
  }

  // Consume the one-shot handshake bounce-back params off the render path,
  // mirroring the Stripe/banking sections.
  useEffect(() => {
    const connected = searchParams.get('woocommerce_connected')
    const error = searchParams.get('woocommerce_error')
    if (!connected && !error) return

    let cancelled = false
    queueMicrotask(() => {
      if (cancelled) return
      if (connected) {
        toast({ title: t('connected_toast_title'), description: t('connected_toast_description') })
      } else if (error) {
        const message =
          error === 'denied' ? t('error_denied')
          : error === 'wrong_user' ? t('error_wrong_user')
          : t('error_generic')
        toast({ title: t('connect_failed_title'), description: message, variant: 'destructive' })
      }
      router.replace('/import?mode=woocommerce')
    })
    return () => { cancelled = true }
  }, [searchParams, router, toast, t])

  async function handleConnect() {
    if (connecting) return
    setConnecting(true)
    try {
      const result = await wooRequest<{ url?: string }>({
        url: '/api/extensions/ext/woocommerce/connect',
        body: { store_url: storeUrl },
        locale,
        timeoutMs: WOO_CONNECT_TIMEOUT_MS,
      })
      if (!result.ok || !result.data?.url) {
        toast({
          title: t('connect_failed_title'),
          description: result.ok ? t('error_generic') : failureDescription(result, failureCopy),
          variant: 'destructive',
        })
        return
      }
      window.location.href = result.data.url
    } finally {
      setConnecting(false)
    }
  }

  async function handleManualConnect() {
    if (connecting) return
    setConnecting(true)
    try {
      const result = await wooRequest({
        url: '/api/extensions/ext/woocommerce/manual-connect',
        body: {
          store_url: storeUrl,
          consumer_key: consumerKey,
          consumer_secret: consumerSecret,
        },
        locale,
        timeoutMs: WOO_CONNECT_TIMEOUT_MS,
      })
      if (!result.ok) {
        toast({
          title: t('connect_failed_title'),
          description: failureDescription(result, failureCopy),
          variant: 'destructive',
        })
        return
      }
      toast({ title: t('connected_toast_title'), description: t('connected_toast_description') })
      setConsumerKey('')
      setConsumerSecret('')
      setStoreUrl('')
      setManualMode(false)
      await loadStatus()
    } finally {
      setConnecting(false)
    }
  }

  async function handleSyncNow(connectionId: string) {
    if (busyId) return
    setBusyId(connectionId)
    try {
      const result = await wooRequest<WooSyncPayload>({
        url: '/api/extensions/ext/woocommerce/sync',
        body: { connection_id: connectionId },
        locale,
        timeoutMs: WOO_SYNC_TIMEOUT_MS,
      })
      if (!result.ok) {
        toast({
          title: t('sync_failed_title'),
          description: failureDescription(result, failureCopy),
          variant: 'destructive',
        })
        return
      }
      const summary = syncSummary(result.data)
      if (summary.reason === 'revoked') {
        toast({
          title: t('sync_failed_title'),
          description: t('sync_revoked'),
          variant: 'destructive',
        })
      } else if (summary.reason === 'partial') {
        toast({ title: t('sync_partial_title'), description: t('sync_partial', summary.values) })
      } else if (summary.reason === 'empty') {
        toast({ title: t('sync_done_title'), description: t('sync_done_empty') })
      } else if (summary.reason === 'errors') {
        toast({ title: t('sync_done_title'), description: t('sync_done_feed_errors', summary.values) })
      } else if (summary.reason === 'feed') {
        toast({ title: t('sync_done_title'), description: t('sync_done_feed', summary.values) })
      } else {
        toast({ title: t('sync_done_title') })
      }
      await loadStatus()
    } finally {
      setBusyId(null)
    }
  }

  async function handleToggleTransactionSync(connectionId: string, enabled: boolean) {
    if (busyId) return
    setBusyId(connectionId)
    try {
      const result = await wooRequest({
        url: '/api/extensions/ext/woocommerce/transaction-sync',
        body: { enabled, connection_id: connectionId },
        locale,
      })
      if (!result.ok) {
        toast({
          title: t('transaction_sync_toggle_failed'),
          description: failureDescription(result, failureCopy),
          variant: 'destructive',
        })
        return
      }
      toast({
        title: enabled
          ? t('transaction_sync_enabled_toast')
          : t('transaction_sync_disabled_toast'),
      })
      await loadStatus()
    } finally {
      setBusyId(null)
    }
  }

  async function handleDisconnect(connectionId: string) {
    if (busyId) return
    setBusyId(connectionId)
    try {
      const result = await wooRequest({
        url: '/api/extensions/ext/woocommerce/disconnect',
        method: 'DELETE',
        body: { connection_id: connectionId },
        locale,
      })
      if (!result.ok) {
        toast({
          title: t('disconnect_failed_title'),
          description: failureDescription(result, failureCopy),
          variant: 'destructive',
        })
        return
      }
      // The key still exists in the store's wp-admin; only the merchant can
      // delete it there, so the toast says so.
      toast({ title: t('disconnected_toast_title'), description: t('disconnected_toast_description') })
      setConfirmDisconnectId(null)
      await loadStatus()
    } finally {
      setBusyId(null)
    }
  }

  if (loading) {
    return (
      <Card>
        <CardContent className="space-y-3 p-6">
          <Skeleton className="h-5 w-48" />
          <Skeleton className="h-4 w-72" />
          <Skeleton className="h-10 w-40" />
        </CardContent>
      </Card>
    )
  }

  if (loadFailed) {
    return (
      <Card>
        <CardHeader>
          <CardTitle className="text-base">{t('title')}</CardTitle>
        </CardHeader>
        <CardContent className="space-y-4 pt-0">
          <p className="text-sm text-destructive">{t('load_failed')}</p>
          <Button variant="outline" size="sm" onClick={retryLoadStatus}>
            <RefreshCw className="mr-2 h-4 w-4" />
            {tCommon('retry')}
          </Button>
        </CardContent>
      </Card>
    )
  }

  if (!configured) {
    return (
      <Card>
        <CardHeader>
          <CardTitle className="text-base">{t('title')}</CardTitle>
        </CardHeader>
        <CardContent className="pt-0">
          <p className="text-sm text-muted-foreground">{t('not_configured')}</p>
        </CardContent>
      </Card>
    )
  }

  const hasActive = connections.some((c) => c.status === 'active')

  return (
    <Card>
      <CardHeader>
        <CardTitle className="text-base">{t('title')}</CardTitle>
      </CardHeader>
      <CardContent className="space-y-6 pt-0">
        <p className="text-sm text-muted-foreground">{t('description')}</p>

        {connections.map((connection) => {
          const isActive = connection.status === 'active'
          const busy = busyId === connection.id
          // Handlers early-return while ANY request runs (shared busyId), so
          // every card's controls disable; the spinner stays on the busy one.
          const blocked = busyId !== null
          return (
            <div key={connection.id} className="space-y-4 rounded-lg border border-border p-4">
              <div className="flex flex-wrap items-center justify-between gap-4">
                <div className="flex items-center gap-3">
                  <ShoppingCart className="h-5 w-5 text-muted-foreground" />
                  <div>
                    <div className="flex items-center gap-2">
                      <span className="text-sm font-medium">
                        {connection.store_name || connection.store_url || t('unnamed_store')}
                      </span>
                      <Badge variant={STATUS_VARIANT[connection.status]}>
                        {t(`status_${connection.status}`)}
                      </Badge>
                    </div>
                    {connection.store_name && (
                      <p className="mt-1 text-sm text-muted-foreground">{connection.store_url}</p>
                    )}
                    {isActive && connection.connected_at && (
                      <p className="mt-1 text-sm text-muted-foreground">
                        {t('connected_since', { date: formatDateLong(connection.connected_at) })}
                      </p>
                    )}
                    {connection.status === 'pending' && (
                      <p className="mt-1 text-sm text-muted-foreground">{t('pending_note')}</p>
                    )}
                    {connection.error_message && (
                      // Shown for active connections too: a sync that cannot
                      // run must not hide behind a healthy "Ansluten" badge.
                      <p className="mt-1 text-sm text-destructive">{connection.error_message}</p>
                    )}
                  </div>
                </div>
                {isActive && (
                  confirmDisconnectId === connection.id ? (
                    <div className="flex items-center gap-2">
                      <Button
                        variant="destructive"
                        size="sm"
                        onClick={() => handleDisconnect(connection.id)}
                        disabled={blocked}
                      >
                        {t('disconnect_confirm')}
                      </Button>
                      <Button
                        variant="outline"
                        size="sm"
                        onClick={() => setConfirmDisconnectId(null)}
                        disabled={blocked}
                      >
                        {t('cancel')}
                      </Button>
                    </div>
                  ) : (
                    <div className="flex items-center gap-2">
                      <Button
                        variant="outline"
                        size="sm"
                        onClick={() => handleSyncNow(connection.id)}
                        disabled={blocked}
                      >
                        {busy ? (
                          <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                        ) : (
                          <RefreshCw className="mr-2 h-4 w-4" />
                        )}
                        {busy ? t('syncing') : t('sync_now')}
                      </Button>
                      <Button
                        variant="outline"
                        size="sm"
                        onClick={() => setConfirmDisconnectId(connection.id)}
                        disabled={blocked}
                      >
                        <Unlink className="mr-2 h-4 w-4" />
                        {t('disconnect')}
                      </Button>
                    </div>
                  )
                )}
              </div>

              {isActive && (
                <div className="flex flex-wrap items-start justify-between gap-4 border-t border-border pt-4">
                  <div className="min-w-0 max-w-prose space-y-1">
                    <p className="text-sm font-medium">{t('transaction_sync_title')}</p>
                    <p className="text-sm text-muted-foreground">
                      {t('transaction_sync_description')}
                    </p>
                    {connection.transaction_sync_enabled ? (
                      <p className="text-xs text-muted-foreground">
                        {connection.last_order_synced_at
                          ? t('transaction_sync_last_synced', {
                              date: formatDateLong(connection.last_order_synced_at),
                            })
                          : t('transaction_sync_never_synced')}
                      </p>
                    ) : (
                      <p className="text-xs text-muted-foreground">
                        {t('transaction_sync_backfill_note')}
                      </p>
                    )}
                  </div>
                  <Switch
                    checked={connection.transaction_sync_enabled}
                    onCheckedChange={(enabled) =>
                      handleToggleTransactionSync(connection.id, enabled)
                    }
                    disabled={blocked}
                    aria-label={t('transaction_sync_title')}
                  />
                </div>
              )}

              {isActive && connection.store_url && (
                <PaymentMethodMappingForm
                  platform="woocommerce"
                  storeScope={storeScopeOf(connection.store_url)}
                />
              )}
            </div>
          )
        })}

        <div className="space-y-4">
          {hasActive && (
            <p className="text-sm font-medium">{t('add_store')}</p>
          )}
          <div className="space-y-2">
            <Label htmlFor="woocommerce-store-url">{t('store_url_label')}</Label>
            <Input
              id="woocommerce-store-url"
              type="url"
              inputMode="url"
              placeholder="https://minbutik.se"
              value={storeUrl}
              onChange={(e) => setStoreUrl(e.target.value)}
              disabled={connecting}
            />
          </div>

          {manualMode ? (
            <div className="space-y-4 rounded-lg border border-border p-4">
              <p className="text-sm text-muted-foreground">{t('manual_hint')}</p>
              <div className="space-y-2">
                <Label htmlFor="woocommerce-consumer-key">{t('consumer_key_label')}</Label>
                <Input
                  id="woocommerce-consumer-key"
                  autoComplete="off"
                  placeholder="ck_..."
                  value={consumerKey}
                  onChange={(e) => setConsumerKey(e.target.value)}
                  disabled={connecting}
                />
              </div>
              <div className="space-y-2">
                <Label htmlFor="woocommerce-consumer-secret">{t('consumer_secret_label')}</Label>
                <Input
                  id="woocommerce-consumer-secret"
                  type="password"
                  autoComplete="off"
                  placeholder="cs_..."
                  value={consumerSecret}
                  onChange={(e) => setConsumerSecret(e.target.value)}
                  disabled={connecting}
                />
              </div>
              <div className="flex items-center gap-2">
                <Button
                  onClick={handleManualConnect}
                  disabled={connecting || !storeUrl || !consumerKey || !consumerSecret}
                >
                  {connecting ? (
                    <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                  ) : (
                    <KeyRound className="mr-2 h-4 w-4" />
                  )}
                  {connecting ? t('connecting') : t('manual_connect')}
                </Button>
                <Button
                  variant="ghost"
                  size="sm"
                  onClick={() => setManualMode(false)}
                  disabled={connecting}
                >
                  {t('cancel')}
                </Button>
              </div>
            </div>
          ) : (
            <div>
              <div className="flex items-center gap-2">
                <Button onClick={handleConnect} disabled={connecting || !storeUrl}>
                  {connecting ? (
                    <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                  ) : (
                    <Link2 className="mr-2 h-4 w-4" />
                  )}
                  {connecting ? t('connecting') : t('connect')}
                </Button>
                <Button
                  variant="ghost"
                  size="sm"
                  onClick={() => setManualMode(true)}
                  disabled={connecting}
                >
                  {t('manual_toggle')}
                </Button>
              </div>
              <p className="mt-3 text-sm text-muted-foreground">{t('connect_hint')}</p>
            </div>
          )}
        </div>
      </CardContent>
    </Card>
  )
}