'use client';

import { useState, useEffect, useCallback } from 'react';
import {
  Bell,
  Send,
  Mail,
  CheckCircle2,
  AlertCircle,
  Loader2,
  Globe,
  CreditCard,
  HardDrive,
} from 'lucide-react';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Separator } from '@/components/ui/separator';
import { Skeleton } from '@/components/ui/skeleton';
import { Badge } from '@/components/ui/badge';
import { Progress } from '@/components/ui/progress';
import {
  Select,
  SelectContent,
  SelectGroup,
  SelectItem,
  SelectLabel,
  SelectTrigger,
  SelectValue,
} from '@/components/ui/select';
import { cn } from '@/lib/utils';
import { CancelSubscriptionDialog } from '@/components/settings/cancel-subscription-dialog';
import type { CancellationReason } from '@/lib/cancellation-reasons';

interface NotificationSettings {
  telegramChatId: string | null;
  telegramEnabled: boolean;
  emailEnabled: boolean;
  onNewVideo: boolean;
  onNewVersion: boolean;
  onNewComment: boolean;
  onNewReply: boolean;
  onApprovalEvents: boolean;
  timezone: string;
}

interface BillingOverview {
  isEnabled: boolean;
  isConfigured: boolean;
  status: 'disabled' | 'ready' | 'misconfigured';
  checkoutAvailable: boolean;
  portalAvailable: boolean;
  subscription: {
    status: string;
    label: string;
    hasActiveSubscription: boolean;
    hasRecoverableSubscription: boolean;
    hasActiveTrial: boolean;
    hasBillingAccess: boolean;
    isPaid: boolean;
    priceId: string | null;
    currentPeriodEnd: string | null;
    cancelAtPeriodEnd: boolean;
    cancelAt: string | null;
    trialEndsAt: string | null;
    billingAccessEndedAt: string | null;
    storageCleanupEligibleAt: string | null;
  };
  workspaceCreation: {
    canCreateWorkspace: boolean;
    canStartTrial?: boolean;
    reason: string | null;
    ownedWorkspaceCount: number;
    invitedWorkspaceCount: number;
  };
}

interface StorageInfo {
  usedBytes: string;
  limitBytes: string;
  percentage: number;
  /** False on the free trial, where the way out is subscribing rather than deleting. */
  isPaid: boolean;
}

function formatBytes(bytesStr: string): string {
  const bytes = Number(bytesStr);
  if (bytes < 1024) return `${bytes} B`;
  if (bytes < 1024 * 1024) return `${(bytes / 1024).toFixed(1)} KB`;
  if (bytes < 1024 * 1024 * 1024) return `${(bytes / (1024 * 1024)).toFixed(1)} MB`;
  return `${(bytes / (1024 * 1024 * 1024)).toFixed(2)} GB`;
}

function ToggleButton({
  enabled,
  onToggle,
  label,
  description,
}: {
  enabled: boolean;
  onToggle: () => void;
  label: string;
  description?: string;
}) {
  return (
    <button
      type="button"
      onClick={onToggle}
      className={cn(
        'flex items-center justify-between w-full p-3 rounded-lg border transition-colors text-left',
        enabled ? 'border-primary/50 bg-primary/5' : 'border-border hover:bg-accent/50'
      )}
    >
      <div className="flex-1 min-w-0 pr-4">
        <span className="text-sm font-medium">{label}</span>
        {description && <p className="text-xs text-muted-foreground mt-0.5">{description}</p>}
      </div>
      <div
        className={cn(
          'w-10 h-6 shrink-0 rounded-full relative transition-colors',
          enabled ? 'bg-primary' : 'bg-muted'
        )}
      >
        <div
          className={cn(
            'absolute top-1 w-4 h-4 rounded-full bg-white transition-transform',
            enabled ? 'translate-x-5' : 'translate-x-1'
          )}
        />
      </div>
    </button>
  );
}

export default function SettingsPage({ billingOnly = false }: { billingOnly?: boolean }) {
  const [settings, setSettings] = useState<NotificationSettings>({
    telegramChatId: null,
    telegramEnabled: false,
    emailEnabled: false,
    onNewVideo: true,
    onNewVersion: true,
    onNewComment: true,
    onNewReply: true,
    onApprovalEvents: true,
    timezone: Intl.DateTimeFormat().resolvedOptions().timeZone || 'UTC',
  });
  const [loading, setLoading] = useState(true);
  const [saving, setSaving] = useState(false);
  const [testing, setTesting] = useState<string | null>(null);
  const [billing, setBilling] = useState<BillingOverview | null>(null);
  const [billingLoading, setBillingLoading] = useState(true);
  const [billingAction, setBillingAction] = useState<
    'checkout' | 'portal' | 'trial' | 'cancel' | null
  >(null);
  const [cancelDialogOpen, setCancelDialogOpen] = useState(false);
  const [storageInfo, setStorageInfo] = useState<StorageInfo | null>(null);
  const [storageLoading, setStorageLoading] = useState(true);
  const [message, setMessage] = useState<{ type: 'success' | 'error'; text: string } | null>(null);

  // Form state for Telegram chat ID (separate from saved settings for editing)
  const [telegramChatId, setTelegramChatId] = useState('');

  const hasScheduledCancellation = Boolean(
    billing?.subscription.cancelAtPeriodEnd || billing?.subscription.cancelAt
  );

  useEffect(() => {
    async function fetchSettings() {
      try {
        const [settingsRes, billingRes, storageRes] = await Promise.all([
          fetch('/api/settings/notifications'),
          fetch('/api/billing'),
          fetch('/api/settings/storage'),
        ]);

        if (settingsRes.ok) {
          const data = await settingsRes.json();
          setSettings(data.data);
          setTelegramChatId(data.data.telegramChatId || '');
        }

        if (billingRes.ok) {
          const data = await billingRes.json();
          setBilling(data.data);
        }

        if (storageRes.ok) {
          const data = await storageRes.json();
          setStorageInfo(data.data);
        }
      } catch {
        console.error('Failed to fetch settings');
      } finally {
        setLoading(false);
        setBillingLoading(false);
        setStorageLoading(false);
      }
    }
    fetchSettings();
  }, []);

  const showMessage = useCallback((type: 'success' | 'error', text: string) => {
    setMessage({ type, text });
    setTimeout(() => setMessage(null), 4000);
  }, []);

  const handleSave = useCallback(async () => {
    setSaving(true);
    try {
      const res = await fetch('/api/settings/notifications', {
        method: 'PUT',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          ...settings,
          telegramChatId: telegramChatId || null,
        }),
      });

      if (res.ok) {
        const data = await res.json();
        setSettings(data.data);
        showMessage('success', 'Settings saved');
      } else {
        const data = await res.json();
        showMessage('error', data.error || 'Failed to save');
      }
    } catch {
      showMessage('error', 'Failed to save settings');
    } finally {
      setSaving(false);
    }
  }, [settings, telegramChatId, showMessage]);

  const handleTest = useCallback(
    async (channel: 'telegram' | 'email') => {
      setTesting(channel);
      try {
        const res = await fetch('/api/settings/notifications', {
          method: 'POST',
          headers: { 'Content-Type': 'application/json' },
          body: JSON.stringify({
            channel,
            telegramChatId,
          }),
        });
        const data = await res.json();
        if (res.ok) {
          showMessage('success', data.data.message);
        } else {
          showMessage('error', data.error || 'Test failed');
        }
      } catch {
        showMessage('error', 'Test failed');
      } finally {
        setTesting(null);
      }
    },
    [telegramChatId, showMessage]
  );

  const handleBillingRedirect = useCallback(
    async (endpoint: '/api/billing/checkout' | '/api/billing/portal') => {
      setBillingAction(endpoint.endsWith('checkout') ? 'checkout' : 'portal');
      try {
        const res = await fetch(endpoint, {
          method: 'POST',
          headers: { 'Content-Type': 'application/json' },
        });
        const data = await res.json();

        if (!res.ok) {
          showMessage('error', data.error || 'Failed to open billing flow');
          return;
        }

        window.location.href = data.data.url;
      } catch {
        showMessage('error', 'Failed to open billing flow');
      } finally {
        setBillingAction(null);
      }
    },
    [showMessage]
  );

  const handleStartTrial = useCallback(async () => {
    setBillingAction('trial');
    try {
      const res = await fetch('/api/billing/trial', { method: 'POST' });
      const data = await res.json();

      if (!res.ok) {
        showMessage('error', data.error || 'Failed to start your free trial');
        return;
      }

      const billingRes = await fetch('/api/billing');
      if (billingRes.ok) {
        setBilling((await billingRes.json()).data);
      }
      showMessage('success', 'Your free trial has started');
    } catch {
      showMessage('error', 'Failed to start your free trial');
    } finally {
      setBillingAction(null);
    }
  }, [showMessage]);

  const handleCancelSubscription = useCallback(
    async (input: { reason: CancellationReason | null; note: string | null }) => {
      setBillingAction('cancel');
      try {
        const res = await fetch('/api/billing/cancel', {
          method: 'POST',
          headers: { 'Content-Type': 'application/json' },
          body: JSON.stringify(input),
        });
        const data = await res.json();

        if (!res.ok) {
          showMessage('error', data.error || 'Failed to cancel subscription');
          return false;
        }

        setCancelDialogOpen(false);
        const billingRes = await fetch('/api/billing');
        if (billingRes.ok) {
          setBilling((await billingRes.json()).data);
        }
        const endsOn = data.data?.periodEnd
          ? new Date(data.data.periodEnd).toLocaleDateString()
          : null;
        showMessage(
          'success',
          endsOn
            ? `Your subscription ends on ${endsOn}. You keep full access until then.`
            : 'Your subscription ends at the close of the current period.'
        );
        return true;
      } catch {
        showMessage('error', 'Failed to cancel subscription');
        return false;
      } finally {
        setBillingAction(null);
      }
    },
    [showMessage]
  );

  if (loading) {
    return (
      <div className="max-w-2xl mx-auto py-8 px-4 space-y-6">
        <div>
          <Skeleton className="h-9 w-56" />
          <Skeleton className="h-4 w-80 mt-2" />
        </div>
        {Array.from({ length: 4 }).map((_, i) => (
          <Card key={i}>
            <CardHeader>
              <Skeleton className="h-5 w-40" />
              <Skeleton className="h-4 w-64 mt-1" />
            </CardHeader>
            <CardContent className="space-y-4">
              {Array.from({ length: 3 }).map((_, j) => (
                <div key={j} className="flex items-center justify-between">
                  <div className="space-y-1">
                    <Skeleton className="h-4 w-32" />
                    <Skeleton className="h-3 w-48" />
                  </div>
                  <Skeleton className="h-5 w-10 rounded-full" />
                </div>
              ))}
            </CardContent>
          </Card>
        ))}
        <div className="flex justify-end">
          <Skeleton className="h-10 w-32 rounded-md" />
        </div>
      </div>
    );
  }

  return (
    <div className="max-w-2xl mx-auto py-8 px-4">
      <div className="mb-8">
        <h1 className="text-2xl font-bold tracking-tight">Settings</h1>
        <p className="text-muted-foreground mt-1">
          {billingOnly ? 'Manage your billing access' : 'Manage your notification preferences'}
        </p>
      </div>

      {/* Status message */}
      {message && (
        <div
          className={cn(
            'flex items-center gap-2 p-3 rounded-lg mb-6 text-sm',
            message.type === 'success'
              ? 'bg-green-500/10 text-green-700 dark:text-green-400'
              : 'bg-destructive/10 text-destructive'
          )}
        >
          {message.type === 'success' ? (
            <CheckCircle2 className="h-4 w-4 shrink-0" />
          ) : (
            <AlertCircle className="h-4 w-4 shrink-0" />
          )}
          {message.text}
        </div>
      )}

      <Card className="mb-6">
        <CardHeader>
          <CardTitle className="flex items-center gap-2">
            <CreditCard className="h-5 w-5" />
            Billing
          </CardTitle>
          <CardDescription>Manage your paid plan and workspace creation access</CardDescription>
        </CardHeader>
        <CardContent className="space-y-4">
          {billingLoading || !billing ? (
            <div className="space-y-3">
              <Skeleton className="h-4 w-40" />
              <Skeleton className="h-4 w-full" />
              <Skeleton className="h-10 w-44 rounded-md" />
            </div>
          ) : !billing.isEnabled ? (
            <div className="rounded-md border border-muted bg-muted/40 p-4 text-sm text-muted-foreground">
              Stripe billing is disabled by this host. Workspace creation is unrestricted in this
              environment.
            </div>
          ) : !billing.isConfigured ? (
            <div className="rounded-md border border-amber-500/30 bg-amber-500/10 p-4 text-sm text-amber-700 dark:text-amber-400">
              Stripe is not configured yet. Add your Stripe environment variables before using
              billing.
            </div>
          ) : (
            <>
              {!billing.subscription.hasActiveSubscription &&
              billing.subscription.hasActiveTrial &&
              billing.subscription.trialEndsAt ? (
                <div className="rounded-md border border-primary/30 bg-primary/5 p-4 space-y-2">
                  <p className="text-sm font-semibold">
                    Your free trial runs until{' '}
                    {new Date(billing.subscription.trialEndsAt).toLocaleDateString()}
                  </p>
                  <p className="text-sm text-muted-foreground">
                    Every feature is on and no card is on file. The trial covers one workspace and
                    one project. Subscribing starts your paid month straight away, so there is no
                    reason to do it before you are ready.
                  </p>
                </div>
              ) : null}

              <div className="flex items-center justify-between rounded-lg border p-4">
                <div>
                  <p className="text-sm font-medium">Current plan</p>
                  <p className="text-sm text-muted-foreground mt-1">
                    {billing.subscription.hasActiveSubscription
                      ? hasScheduledCancellation
                        ? billing.subscription.hasActiveTrial
                          ? 'Trial canceled. Access remains active until the trial ends.'
                          : 'Subscription canceled. Access remains active until the end of the current billing period.'
                        : 'Paid account with workspace creation unlocked.'
                      : billing.subscription.hasActiveTrial
                        ? 'Free trial, no card required.'
                        : 'Billing access has ended.'}
                  </p>
                </div>
                <Badge
                  variant={billing.subscription.hasActiveSubscription ? 'default' : 'secondary'}
                >
                  {billing.subscription.label}
                </Badge>
              </div>

              {billing.subscription.hasRecoverableSubscription &&
              !billing.subscription.hasActiveSubscription ? (
                <p className="rounded-md border border-destructive/30 bg-destructive/10 px-3 py-2 text-sm font-medium text-destructive">
                  Your latest payment didn&apos;t go through. Update your payment method to keep
                  your subscription — starting a new one would create a duplicate.
                </p>
              ) : null}

              {billing.subscription.hasActiveTrial &&
              billing.subscription.trialEndsAt &&
              hasScheduledCancellation ? (
                <p className="rounded-md border border-destructive/30 bg-destructive/10 px-3 py-2 text-sm font-medium text-destructive">
                  Access ends on {new Date(billing.subscription.trialEndsAt).toLocaleDateString()}.
                </p>
              ) : null}

              {billing.subscription.currentPeriodEnd ? (
                <p className="text-sm text-muted-foreground">
                  {hasScheduledCancellation
                    ? 'Your subscription ends on '
                    : 'Current billing period ends on '}
                  {new Date(billing.subscription.currentPeriodEnd).toLocaleDateString()}.
                </p>
              ) : null}

              {hasScheduledCancellation && billing.subscription.cancelAt ? (
                <p className="text-sm text-muted-foreground">
                  Cancellation was scheduled on{' '}
                  {new Date(billing.subscription.cancelAt).toLocaleDateString()}.
                </p>
              ) : null}

              {/* Deliberately not conditioned on `billingAccessEndedAt`: an account that
                  only ever had the cardless trial never gets one written, and it is exactly
                  that account which most needs to be told its work is still recoverable. */}
              {!billing.subscription.hasBillingAccess &&
              billing.subscription.storageCleanupEligibleAt ? (
                <p className="text-sm text-amber-700 dark:text-amber-400">
                  Nothing has been deleted. Your projects and media are kept until{' '}
                  {new Date(billing.subscription.storageCleanupEligibleAt).toLocaleDateString()};
                  subscribe before then and everything is where you left it.
                </p>
              ) : null}

              {!billing.workspaceCreation.canCreateWorkspace ? (
                <div className="rounded-lg border bg-muted/30 p-4 space-y-2">
                  <p className="text-sm font-medium">Workspace creation</p>
                  <p className="text-sm text-muted-foreground">
                    {billing.workspaceCreation.reason || 'Upgrade to create another workspace.'}
                  </p>
                </div>
              ) : null}

              <div className="flex flex-col sm:flex-row gap-3">
                {billing.subscription.hasRecoverableSubscription && billing.portalAvailable ? (
                  <Button
                    onClick={() => handleBillingRedirect('/api/billing/portal')}
                    disabled={billingAction !== null}
                  >
                    {billingAction === 'portal' ? (
                      <>
                        <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                        Opening Portal...
                      </>
                    ) : billing.subscription.hasActiveSubscription ? (
                      'Manage Subscription'
                    ) : (
                      'Update Payment Method'
                    )}
                  </Button>
                ) : null}
                {/* Beside the portal button, not inside it. Someone who came to
                    cancel should not have to guess that "Manage" is the way, and
                    the portal cannot ask why they are leaving. */}
                {billing.subscription.hasActiveSubscription &&
                billing.portalAvailable &&
                !hasScheduledCancellation ? (
                  <Button
                    variant="ghost"
                    className="text-muted-foreground"
                    onClick={() => setCancelDialogOpen(true)}
                    disabled={billingAction !== null}
                  >
                    Cancel subscription
                  </Button>
                ) : null}
                {billing.subscription.hasRecoverableSubscription &&
                billing.portalAvailable ? null : (
                  <>
                    {billing.workspaceCreation.canStartTrial ? (
                      <Button onClick={handleStartTrial} disabled={billingAction !== null}>
                        {billingAction === 'trial' ? (
                          <>
                            <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                            Starting Trial...
                          </>
                        ) : (
                          'Start Free Trial'
                        )}
                      </Button>
                    ) : null}
                    <Button
                      variant={billing.workspaceCreation.canStartTrial ? 'outline' : 'default'}
                      onClick={() => handleBillingRedirect('/api/billing/checkout')}
                      disabled={!billing.checkoutAvailable || billingAction !== null}
                    >
                      {billingAction === 'checkout' ? (
                        <>
                          <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                          Redirecting...
                        </>
                      ) : (
                        'Upgrade with Stripe'
                      )}
                    </Button>
                  </>
                )}
              </div>
            </>
          )}
        </CardContent>
      </Card>

      {billing ? (
        <CancelSubscriptionDialog
          open={cancelDialogOpen}
          onOpenChange={setCancelDialogOpen}
          periodEnd={billing.subscription.currentPeriodEnd}
          isTrial={billing.subscription.status === 'TRIALING'}
          onConfirm={handleCancelSubscription}
        />
      ) : null}

      {billing?.subscription.hasBillingAccess && (
        <Card className="mb-6">
          <CardHeader>
            <CardTitle className="flex items-center gap-2">
              <HardDrive className="h-5 w-5" />
              Storage
            </CardTitle>
            <CardDescription>
              Combined usage across video files and media attachments
              {storageInfo ? ` (${formatBytes(storageInfo.limitBytes)} limit)` : ''}
            </CardDescription>
          </CardHeader>
          <CardContent className="space-y-3">
            {storageLoading || !storageInfo ? (
              <div className="space-y-2">
                <Skeleton className="h-4 w-48" />
                <Skeleton className="h-2 w-full rounded-full" />
              </div>
            ) : (
              <>
                <div className="flex items-center justify-between text-sm">
                  <span className="text-muted-foreground">
                    {formatBytes(storageInfo.usedBytes)} used of{' '}
                    {formatBytes(storageInfo.limitBytes)}
                  </span>
                  <span
                    className={
                      storageInfo.percentage >= 90
                        ? 'text-destructive font-medium'
                        : storageInfo.percentage >= 75
                          ? 'text-amber-600 dark:text-amber-400 font-medium'
                          : 'text-muted-foreground'
                    }
                  >
                    {storageInfo.percentage < 0.1
                      ? '<0.1%'
                      : `${storageInfo.percentage.toFixed(1)}%`}
                  </span>
                </div>
                <Progress
                  value={storageInfo.percentage}
                  className={
                    storageInfo.percentage >= 90
                      ? '[&>div]:bg-destructive'
                      : storageInfo.percentage >= 75
                        ? '[&>div]:bg-amber-500'
                        : ''
                  }
                />
                {storageInfo.percentage >= 90 &&
                  (storageInfo.isPaid ? (
                    <p className="text-xs text-destructive">
                      Storage is almost full. Delete unused files or contact support.
                    </p>
                  ) : (
                    <p className="text-xs text-destructive">
                      Your free trial storage is almost full. Subscribe above for more room, or
                      delete unused files.
                    </p>
                  ))}
              </>
            )}
          </CardContent>
        </Card>
      )}

      {!billingOnly && (
        <>
          {/* Event Subscriptions */}
          <Card className="mb-6">
            <CardHeader>
              <CardTitle className="flex items-center gap-2">
                <Bell className="h-5 w-5" />
                Notification Events
              </CardTitle>
              <CardDescription>Choose which events trigger notifications</CardDescription>
            </CardHeader>
            <CardContent className="space-y-4">
              <ToggleButton
                enabled={settings.onNewVideo}
                onToggle={() => setSettings((s) => ({ ...s, onNewVideo: !s.onNewVideo }))}
                label="New Video Added"
                description="When a new video is added to one of your projects"
              />
              <ToggleButton
                enabled={settings.onNewVersion}
                onToggle={() => setSettings((s) => ({ ...s, onNewVersion: !s.onNewVersion }))}
                label="New Version Added"
                description="When a new version is added to an existing video"
              />
              <ToggleButton
                enabled={settings.onNewComment}
                onToggle={() => setSettings((s) => ({ ...s, onNewComment: !s.onNewComment }))}
                label="New Comment"
                description="When someone leaves a comment on your videos"
              />
              <ToggleButton
                enabled={settings.onNewReply}
                onToggle={() => setSettings((s) => ({ ...s, onNewReply: !s.onNewReply }))}
                label="New Reply"
                description="When someone replies to a comment thread"
              />
              <ToggleButton
                enabled={settings.onApprovalEvents}
                onToggle={() =>
                  setSettings((s) => ({ ...s, onApprovalEvents: !s.onApprovalEvents }))
                }
                label="Approval Workflow"
                description="When approval requests are created, responded to, or finalized"
              />
            </CardContent>
          </Card>

          {/* Telegram */}
          <Card className="mb-6">
            <CardHeader>
              <div className="flex items-center justify-between">
                <CardTitle className="flex items-center gap-2">
                  <Send className="h-5 w-5" />
                  Telegram
                </CardTitle>
                <Badge variant={settings.telegramEnabled ? 'default' : 'secondary'}>
                  {settings.telegramEnabled ? 'Enabled' : 'Disabled'}
                </Badge>
              </div>
              <CardDescription>Get instant notifications via Telegram</CardDescription>
            </CardHeader>
            <CardContent className="space-y-4">
              <div className="rounded-md border bg-muted/40 p-3 space-y-2 text-sm text-muted-foreground">
                <p className="font-medium text-foreground">Setup instructions</p>
                <ol className="space-y-1.5 list-decimal list-inside">
                  <li>
                    Message{' '}
                    <a
                      href="https://t.me/UserInfeBot"
                      target="_blank"
                      rel="noopener noreferrer"
                      className="text-primary underline underline-offset-2"
                    >
                      @UserInfeBot
                    </a>{' '}
                    on Telegram and send{' '}
                    <code className="bg-muted px-1 rounded text-xs">/start</code> to get your Chat
                    ID
                  </li>
                  <li>
                    Start{' '}
                    <a
                      href="https://t.me/openframe_bot"
                      target="_blank"
                      rel="noopener noreferrer"
                      className="text-primary underline underline-offset-2"
                    >
                      @openframe_bot
                    </a>{' '}
                    and send <code className="bg-muted px-1 rounded text-xs">/start</code> so it can
                    message you
                  </li>
                  <li>Paste your Chat ID below and enable notifications</li>
                </ol>
              </div>

              <div>
                <Label htmlFor="telegram-chat-id">Your Chat ID</Label>
                <Input
                  id="telegram-chat-id"
                  placeholder="123456789"
                  value={telegramChatId}
                  onChange={(e) => setTelegramChatId(e.target.value)}
                  className="mt-1 font-mono text-sm"
                />
              </div>

              <ToggleButton
                enabled={settings.telegramEnabled}
                onToggle={() => setSettings((s) => ({ ...s, telegramEnabled: !s.telegramEnabled }))}
                label="Enable Telegram notifications"
              />

              <Button
                variant="outline"
                size="sm"
                onClick={() => handleTest('telegram')}
                disabled={!telegramChatId || testing === 'telegram'}
              >
                {testing === 'telegram' ? (
                  <Loader2 className="h-4 w-4 animate-spin mr-2" />
                ) : (
                  <Send className="h-4 w-4 mr-2" />
                )}
                Send Test Message
              </Button>
            </CardContent>
          </Card>

          {/* Email */}
          <Card className="mb-6">
            <CardHeader>
              <div className="flex items-center justify-between">
                <CardTitle className="flex items-center gap-2">
                  <Mail className="h-5 w-5" />
                  Email
                </CardTitle>
                <Badge variant={settings.emailEnabled ? 'default' : 'secondary'}>
                  {settings.emailEnabled ? 'Enabled' : 'Disabled'}
                </Badge>
              </div>
              <CardDescription>
                Receive notification emails to your account email address
              </CardDescription>
            </CardHeader>
            <CardContent className="space-y-4">
              <ToggleButton
                enabled={settings.emailEnabled}
                onToggle={() => setSettings((s) => ({ ...s, emailEnabled: !s.emailEnabled }))}
                label="Enable email notifications"
              />

              <Button
                variant="outline"
                size="sm"
                onClick={() => handleTest('email')}
                disabled={!settings.emailEnabled || testing === 'email'}
              >
                {testing === 'email' ? (
                  <Loader2 className="h-4 w-4 animate-spin mr-2" />
                ) : (
                  <Mail className="h-4 w-4 mr-2" />
                )}
                Send Test Email
              </Button>
            </CardContent>
          </Card>

          {/* Timezone */}
          <Card className="mb-6">
            <CardHeader>
              <CardTitle className="flex items-center gap-2">
                <Globe className="h-5 w-5" />
                Timezone
              </CardTitle>
              <CardDescription>Timestamps in notifications will use this timezone</CardDescription>
            </CardHeader>
            <CardContent>
              <Select
                value={settings.timezone}
                onValueChange={(value) => setSettings((s) => ({ ...s, timezone: value }))}
              >
                <SelectTrigger className="w-full">
                  <SelectValue placeholder="Select timezone" />
                </SelectTrigger>
                <SelectContent>
                  <SelectGroup>
                    <SelectLabel>Americas</SelectLabel>
                    <SelectItem value="America/New_York">Eastern Time (New York)</SelectItem>
                    <SelectItem value="America/Chicago">Central Time (Chicago)</SelectItem>
                    <SelectItem value="America/Denver">Mountain Time (Denver)</SelectItem>
                    <SelectItem value="America/Los_Angeles">Pacific Time (Los Angeles)</SelectItem>
                    <SelectItem value="America/Anchorage">Alaska (Anchorage)</SelectItem>
                    <SelectItem value="Pacific/Honolulu">Hawaii (Honolulu)</SelectItem>
                    <SelectItem value="America/Toronto">Toronto</SelectItem>
                    <SelectItem value="America/Vancouver">Vancouver</SelectItem>
                    <SelectItem value="America/Mexico_City">Mexico City</SelectItem>
                    <SelectItem value="America/Sao_Paulo">São Paulo</SelectItem>
                    <SelectItem value="America/Argentina/Buenos_Aires">Buenos Aires</SelectItem>
                    <SelectItem value="America/Bogota">Bogotá</SelectItem>
                  </SelectGroup>
                  <SelectGroup>
                    <SelectLabel>Europe</SelectLabel>
                    <SelectItem value="Europe/London">London (GMT/BST)</SelectItem>
                    <SelectItem value="Europe/Paris">Paris (CET)</SelectItem>
                    <SelectItem value="Europe/Berlin">Berlin (CET)</SelectItem>
                    <SelectItem value="Europe/Amsterdam">Amsterdam (CET)</SelectItem>
                    <SelectItem value="Europe/Madrid">Madrid (CET)</SelectItem>
                    <SelectItem value="Europe/Rome">Rome (CET)</SelectItem>
                    <SelectItem value="Europe/Zurich">Zurich (CET)</SelectItem>
                    <SelectItem value="Europe/Stockholm">Stockholm (CET)</SelectItem>
                    <SelectItem value="Europe/Helsinki">Helsinki (EET)</SelectItem>
                    <SelectItem value="Europe/Athens">Athens (EET)</SelectItem>
                    <SelectItem value="Europe/Istanbul">Istanbul (TRT)</SelectItem>
                    <SelectItem value="Europe/Moscow">Moscow (MSK)</SelectItem>
                    <SelectItem value="Europe/Kiev">Kyiv (EET)</SelectItem>
                    <SelectItem value="Europe/Warsaw">Warsaw (CET)</SelectItem>
                  </SelectGroup>
                  <SelectGroup>
                    <SelectLabel>Asia & Pacific</SelectLabel>
                    <SelectItem value="Asia/Dubai">Dubai (GST)</SelectItem>
                    <SelectItem value="Asia/Kolkata">India (IST)</SelectItem>
                    <SelectItem value="Asia/Bangkok">Bangkok (ICT)</SelectItem>
                    <SelectItem value="Asia/Singapore">Singapore (SGT)</SelectItem>
                    <SelectItem value="Asia/Hong_Kong">Hong Kong (HKT)</SelectItem>
                    <SelectItem value="Asia/Shanghai">Shanghai (CST)</SelectItem>
                    <SelectItem value="Asia/Tokyo">Tokyo (JST)</SelectItem>
                    <SelectItem value="Asia/Seoul">Seoul (KST)</SelectItem>
                    <SelectItem value="Asia/Taipei">Taipei (CST)</SelectItem>
                    <SelectItem value="Asia/Jakarta">Jakarta (WIB)</SelectItem>
                    <SelectItem value="Australia/Sydney">Sydney (AEST)</SelectItem>
                    <SelectItem value="Australia/Melbourne">Melbourne (AEST)</SelectItem>
                    <SelectItem value="Australia/Perth">Perth (AWST)</SelectItem>
                    <SelectItem value="Pacific/Auckland">Auckland (NZST)</SelectItem>
                  </SelectGroup>
                  <SelectGroup>
                    <SelectLabel>Africa & Middle East</SelectLabel>
                    <SelectItem value="Africa/Cairo">Cairo (EET)</SelectItem>
                    <SelectItem value="Africa/Lagos">Lagos (WAT)</SelectItem>
                    <SelectItem value="Africa/Johannesburg">Johannesburg (SAST)</SelectItem>
                    <SelectItem value="Africa/Nairobi">Nairobi (EAT)</SelectItem>
                    <SelectItem value="Asia/Riyadh">Riyadh (AST)</SelectItem>
                    <SelectItem value="Asia/Tehran">Tehran (IRST)</SelectItem>
                  </SelectGroup>
                  <SelectGroup>
                    <SelectLabel>Other</SelectLabel>
                    <SelectItem value="UTC">UTC</SelectItem>
                  </SelectGroup>
                </SelectContent>
              </Select>
            </CardContent>
          </Card>

          <Separator className="my-6" />

          {/* Save button */}
          <div className="flex justify-end">
            <Button onClick={handleSave} disabled={saving}>
              {saving ? (
                <>
                  <Loader2 className="h-4 w-4 animate-spin mr-2" />
                  Saving...
                </>
              ) : (
                'Save Settings'
              )}
            </Button>
          </div>
        </>
      )}
    </div>
  );
}