/**
 * Plans & Billing Page - Consolidated
 * Tabs: Current Plan, Upgrade/Downgrade, Credits Overview, Purchase Credits, Billing History, Payment Methods
 */

import { useState, useEffect, useRef } from 'react';
import { 
  CreditCard, Package, TrendingUp, FileText, Wallet, ArrowUpCircle,
  Loader2, AlertCircle, CheckCircle, Download 
} from 'lucide-react';
import { Card } from '../../components/ui/card';
import Badge from '../../components/ui/badge/Badge';
import Button from '../../components/ui/button/Button';
import { useToast } from '../../components/ui/toast/ToastContainer';
import {
  getCreditBalance,
  getCreditPackages,
  getInvoices,
  getAvailablePaymentMethods,
  purchaseCreditPackage,
  downloadInvoicePDF,
  getPayments,
  submitManualPayment,
  createPaymentMethod,
  deletePaymentMethod,
  setDefaultPaymentMethod,
  type CreditBalance,
  type CreditPackage,
  type Invoice,
  type PaymentMethod,
  type Payment,
  getPlans,
  getSubscriptions,
  createSubscription,
  cancelSubscription,
  type Plan,
  type Subscription,
} from '../../services/billing.api';
import { useAuthStore } from '../../store/authStore';

type TabType = 'plan' | 'credits' | 'billing-history';

export default function PlansAndBillingPage() {
  const [activeTab, setActiveTab] = useState<TabType>('plan');
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string>('');
  const [planLoadingId, setPlanLoadingId] = useState<number | null>(null);
  const [purchaseLoadingId, setPurchaseLoadingId] = useState<number | null>(null);

  // Data states
  const [creditBalance, setCreditBalance] = useState<CreditBalance | null>(null);
  const [packages, setPackages] = useState<CreditPackage[]>([]);
  const [invoices, setInvoices] = useState<Invoice[]>([]);
  const [payments, setPayments] = useState<Payment[]>([]);
  const [paymentMethods, setPaymentMethods] = useState<PaymentMethod[]>([]);
  const [plans, setPlans] = useState<Plan[]>([]);
  const [subscriptions, setSubscriptions] = useState<Subscription[]>([]);
  const [selectedPaymentMethod, setSelectedPaymentMethod] = useState<string | undefined>(undefined);
  const [manualPayment, setManualPayment] = useState({
    invoice_id: '',
    amount: '',
    payment_method: '',
    reference: '',
    notes: '',
  });
  const [newPaymentMethod, setNewPaymentMethod] = useState({
    type: 'bank_transfer',
    display_name: '',
    instructions: '',
  });
  const { user } = useAuthStore.getState();
  const hasLoaded = useRef(false);
  const isAwsAdmin = user?.account?.slug === 'aws-admin';
  const handleBillingError = (err: any, fallback: string) => {
    const message = err?.message || fallback;
    setError(message);
    toast?.error?.(message);
  };

  const toast = useToast();

  useEffect(() => {
    if (hasLoaded.current) return;
    hasLoaded.current = true;
    loadData();
  }, []);

  const loadData = async (allowRetry = true) => {
    try {
      setLoading(true);
      // Fetch in controlled sequence to avoid burst 429s on auth/system scopes
      const balanceData = await getCreditBalance();

      // Small gap between auth endpoints to satisfy tight throttles
      const wait = (ms: number) => new Promise((res) => setTimeout(res, ms));

      const packagesPromise = getCreditPackages();
      const invoicesPromise = getInvoices({});
      const paymentsPromise = getPayments({});
      const methodsPromise = getAvailablePaymentMethods();

      const plansData = await getPlans();
      await wait(400);

      // Subscriptions: retry once on 429 after short backoff; do not hard-fail page
      let subsData: { results: Subscription[] } = { results: [] };
      try {
        subsData = await getSubscriptions();
      } catch (subErr: any) {
        if (subErr?.status === 429 && allowRetry) {
          await wait(2500);
          try {
            subsData = await getSubscriptions();
          } catch {
            subsData = { results: [] };
          }
        } else {
          subsData = { results: [] };
        }
      }

      const [packagesData, invoicesData, paymentsData, methodsData] = await Promise.all([
        packagesPromise,
        invoicesPromise,
        paymentsPromise,
        methodsPromise,
      ]);

      setCreditBalance(balanceData);
      setPackages(packagesData.results || []);
      setInvoices(invoicesData.results || []);
      setPayments(paymentsData.results || []);

      // Prefer manual payment method id 14 as default (tenant-facing)
      const methods = (methodsData.results || []).filter((m) => m.is_enabled !== false);
      setPaymentMethods(methods);
      if (methods.length > 0) {
        // Preferred ordering: bank_transfer (default), then manual
        const bank = methods.find((m) => m.type === 'bank_transfer');
        const manual = methods.find((m) => m.type === 'manual');
        const selected =
          bank ||
          manual ||
          methods.find((m) => m.is_default) ||
          methods[0];
        setSelectedPaymentMethod((prev) => prev || selected.type || selected.id);
      }

      // Surface all active plans (avoid hiding plans and showing empty state)
      const activePlans = (plansData.results || []).filter((p) => p.is_active !== false);
      // Exclude Enterprise plan for non aws-admin accounts
      const filteredPlans = activePlans.filter((p) => {
        const name = (p.name || '').toLowerCase();
        const slug = (p.slug || '').toLowerCase();
        const isEnterprise = name.includes('enterprise') || slug === 'enterprise';
        return isAwsAdmin ? true : !isEnterprise;
      });

      // Ensure the user's assigned plan is included even if subscriptions list is empty
      const accountPlan = user?.account?.plan;
      const isAccountEnterprise = (() => {
        if (!accountPlan) return false;
        const name = (accountPlan.name || '').toLowerCase();
        const slug = (accountPlan.slug || '').toLowerCase();
        return name.includes('enterprise') || slug === 'enterprise';
      })();

      const shouldIncludeAccountPlan = accountPlan && (!isAccountEnterprise || isAwsAdmin);
      if (shouldIncludeAccountPlan && !filteredPlans.find((p) => p.id === accountPlan.id)) {
        filteredPlans.push(accountPlan as any);
      }
      setPlans(filteredPlans);
      const subs = subsData.results || [];
      if (subs.length === 0 && shouldIncludeAccountPlan && accountPlan) {
        subs.push({
          id: accountPlan.id || 0,
          plan: accountPlan,
          status: 'active',
        } as any);
      }
      setSubscriptions(subs);
    } catch (err: any) {
      // Handle throttling gracefully: don't block the page on subscriptions throttle
      if (err?.status === 429 && allowRetry) {
        setError('Request was throttled. Retrying...');
        setTimeout(() => loadData(false), 2500);
      } else if (err?.status === 429) {
        setError(''); // suppress lingering banner
      } else {
        setError(err.message || 'Failed to load billing data');
        console.error('Billing load error:', err);
      }
    } finally {
      setLoading(false);
    }
  };

  const handleSelectPlan = async (planId: number) => {
    try {
      if (!selectedPaymentMethod && paymentMethods.length > 0) {
        setError('Select a payment method to continue');
        return;
      }
      setPlanLoadingId(planId);
      await createSubscription({ plan_id: planId, payment_method: selectedPaymentMethod });
      toast?.success?.('Subscription updated');
      await loadData();
    } catch (err: any) {
      handleBillingError(err, 'Failed to update subscription');
    } finally {
      setPlanLoadingId(null);
    }
  };

  const handleCancelSubscription = async () => {
    if (!currentSubscription?.id) {
      setError('No active subscription to cancel');
      return;
    }
    try {
      setPlanLoadingId(currentSubscription.id);
      await cancelSubscription(currentSubscription.id);
      toast?.success?.('Subscription cancellation requested');
      await loadData();
    } catch (err: any) {
      handleBillingError(err, 'Failed to cancel subscription');
    } finally {
      setPlanLoadingId(null);
    }
  };

  const handlePurchase = async (packageId: number) => {
    try {
      if (!selectedPaymentMethod && paymentMethods.length > 0) {
        setError('Select a payment method to continue');
        return;
      }
      setPurchaseLoadingId(packageId);
      await purchaseCreditPackage({
        package_id: packageId,
        payment_method: (selectedPaymentMethod as any) || 'stripe',
      });
      await loadData();
    } catch (err: any) {
      handleBillingError(err, 'Failed to purchase credits');
    } finally {
      setPurchaseLoadingId(null);
      setLoading(false);
    }
  };

  const handleDownloadInvoice = async (invoiceId: number) => {
    try {
      const blob = await downloadInvoicePDF(invoiceId);
      const url = window.URL.createObjectURL(blob);
      const link = document.createElement('a');
      link.href = url;
      link.download = `invoice-${invoiceId}.pdf`;
      document.body.appendChild(link);
      link.click();
      link.remove();
      window.URL.revokeObjectURL(url);
    } catch (err: any) {
      handleBillingError(err, 'Failed to download invoice');
    }
  };

  const handleSubmitManualPayment = async () => {
    try {
      const payload = {
        invoice_id: manualPayment.invoice_id ? Number(manualPayment.invoice_id) : undefined,
        amount: manualPayment.amount,
        payment_method: manualPayment.payment_method || (selectedPaymentMethod as any) || 'manual',
        reference: manualPayment.reference,
        notes: manualPayment.notes,
      };
      await submitManualPayment(payload as any);
      toast?.success?.('Manual payment submitted');
      setManualPayment({ invoice_id: '', amount: '', payment_method: '', reference: '', notes: '' });
      await loadData();
    } catch (err: any) {
      handleBillingError(err, 'Failed to submit payment');
    }
  };

  const handleAddPaymentMethod = async () => {
    if (!newPaymentMethod.display_name.trim()) {
      setError('Payment method name is required');
      return;
    }
    try {
      await createPaymentMethod(newPaymentMethod as any);
      toast?.success?.('Payment method added');
    setNewPaymentMethod({ type: 'bank_transfer', display_name: '', instructions: '' });
      await loadData();
    } catch (err: any) {
      handleBillingError(err, 'Failed to add payment method');
    }
  };

  const handleRemovePaymentMethod = async (id: string) => {
    try {
      await deletePaymentMethod(id);
      toast?.success?.('Payment method removed');
      await loadData();
    } catch (err: any) {
      handleBillingError(err, 'Failed to remove payment method');
    }
  };

  const handleSetDefaultPaymentMethod = async (id: string) => {
    try {
      await setDefaultPaymentMethod(id);
      toast?.success?.('Default payment method updated');
      await loadData();
    } catch (err: any) {
      handleBillingError(err, 'Failed to set default');
    }
  };

  if (loading) {
    return (
      <div className="flex items-center justify-center min-h-screen">
        <Loader2 className="w-8 h-8 animate-spin text-blue-600" />
      </div>
    );
  }

  const currentSubscription = subscriptions.find((sub) => sub.status === 'active') || subscriptions[0];
  const currentPlanId = typeof currentSubscription?.plan === 'object' ? currentSubscription.plan.id : currentSubscription?.plan;
  // Fallback to account plan if subscription is missing
  const accountPlanId = user?.account?.plan?.id;
  const effectivePlanId = currentPlanId || accountPlanId;
  const currentPlan = plans.find((p) => p.id === effectivePlanId) || user?.account?.plan;
  const hasActivePlan = Boolean(effectivePlanId);
  const hasPaymentMethods = paymentMethods.length > 0;
  const subscriptionStatus = currentSubscription?.status || (hasActivePlan ? 'active' : 'none');
  const hasPendingManualPayment = payments.some((p) => p.status === 'pending_approval');

  const tabs = [
    { id: 'plan' as TabType, label: 'Current Plan', icon: <Package className="w-4 h-4" /> },
    { id: 'credits' as TabType, label: 'Credits Overview', icon: <TrendingUp className="w-4 h-4" /> },
    { id: 'billing-history' as TabType, label: 'Billing History', icon: <FileText className="w-4 h-4" /> },
  ];

  return (
    <div className="p-6">
      <div className="mb-6">
        <h1 className="text-2xl font-bold text-gray-900 dark:text-white">Plans & Billing</h1>
        <p className="text-gray-600 dark:text-gray-400 mt-1">
          Manage your subscription, credits, and billing information
        </p>
      </div>

      {/* Activation / pending payment notice */}
      {!hasActivePlan && (
        <div className="mb-4 p-4 rounded-lg border border-amber-200 bg-amber-50 text-amber-800 dark:border-amber-800 dark:bg-amber-900/20 dark:text-amber-200">
          No active plan. Choose a plan below to activate your account.
        </div>
      )}
      {hasPendingManualPayment && (
        <div className="mb-4 p-4 rounded-lg border border-blue-200 bg-blue-50 text-blue-800 dark:border-blue-800 dark:bg-blue-900/20 dark:text-blue-100">
          We received your manual payment. It’s pending admin approval; activation will complete once approved.
        </div>
      )}

      {error && (
        <div className="mb-6 p-4 bg-red-50 dark:bg-red-900/20 border border-red-200 dark:border-red-800 rounded-lg flex items-center gap-3">
          <AlertCircle className="w-5 h-5 text-red-600" />
          <p className="text-red-800 dark:text-red-200">{error}</p>
        </div>
      )}

      {/* Tabs */}
      <div className="mb-6 border-b border-gray-200 dark:border-gray-700">
        <nav className="-mb-px flex space-x-8 overflow-x-auto">
          {tabs.map((tab) => (
            <button
              type="button"
              key={tab.id}
              onClick={() => setActiveTab(tab.id)}
              className={`
                flex items-center gap-2 py-4 px-1 border-b-2 font-medium text-sm whitespace-nowrap
                ${activeTab === tab.id
                  ? 'border-blue-500 text-blue-600 dark:text-blue-400'
                  : 'border-transparent text-gray-500 hover:text-gray-700 hover:border-gray-300 dark:text-gray-400 dark:hover:text-gray-300'
                }
              `}
            >
              {tab.icon}
              {tab.label}
            </button>
          ))}
        </nav>
      </div>

      {/* Tab Content */}
      <div className="mt-6">
        {/* Current Plan Tab */}
        {activeTab === 'plan' && (
          <div className="space-y-6">
            <Card className="p-6">
              <h2 className="text-lg font-semibold mb-4">Your Current Plan</h2>
              {!hasActivePlan && (
                <div className="p-4 mb-4 rounded-lg border border-amber-200 bg-amber-50 text-amber-800 dark:border-amber-800 dark:bg-amber-900/20 dark:text-amber-200">
                  No active plan found. Please choose a plan to activate your account.
                </div>
              )}
              <div className="space-y-4">
                <div className="flex items-center justify-between">
                  <div>
                    <div className="text-2xl font-bold text-gray-900 dark:text-white">
                      {currentPlan?.name || 'No Plan Selected'}
                    </div>
                    <div className="text-gray-600 dark:text-gray-400">
                      {currentPlan?.description || 'Select a plan to unlock full access.'}
                    </div>
                  </div>
                  <Badge variant="light" color={hasActivePlan ? 'success' : 'warning'}>
                    {hasActivePlan ? subscriptionStatus : 'plan required'}
                  </Badge>
                </div>
                <div className="grid grid-cols-1 md:grid-cols-3 gap-4 mt-6">
                  <div className="p-4 bg-gray-50 dark:bg-gray-800 rounded-lg">
                    <div className="text-sm text-gray-600 dark:text-gray-400">Monthly Credits</div>
                    <div className="text-2xl font-bold text-gray-900 dark:text-white">
                      {creditBalance?.plan_credits_per_month?.toLocaleString?.() || 0}
                    </div>
                  </div>
                  <div className="p-4 bg-gray-50 dark:bg-gray-800 rounded-lg">
                    <div className="text-sm text-gray-600 dark:text-gray-400">Current Balance</div>
                    <div className="text-2xl font-bold text-gray-900 dark:text-white">
                      {creditBalance?.credits?.toLocaleString?.() || 0}
                    </div>
                  </div>
                  <div className="p-4 bg-gray-50 dark:bg-gray-800 rounded-lg">
                    <div className="text-sm text-gray-600 dark:text-gray-400">Period Ends</div>
                    <div className="text-2xl font-bold text-gray-900 dark:text-white text-base">
                      {currentSubscription?.current_period_end
                        ? new Date(currentSubscription.current_period_end).toLocaleDateString()
                        : '—'}
                    </div>
                  </div>
                </div>
                <div className="mt-6 flex gap-3">
                  <Button variant="primary" tone="brand" onClick={() => setActiveTab('upgrade')}>
                    {hasActivePlan ? 'Change Plan' : 'Choose a Plan'}
                  </Button>
                  <Button variant="outline" tone="neutral" onClick={() => setActiveTab('purchase')}>
                    Purchase Credits
                  </Button>
                  {hasActivePlan && (
                    <Button
                      variant="outline"
                      tone="neutral"
                      disabled={planLoadingId === currentSubscription?.id}
                      onClick={handleCancelSubscription}
                    >
                      {planLoadingId === currentSubscription?.id ? 'Cancelling...' : 'Cancel Subscription'}
                    </Button>
                  )}
                </div>
              </div>
            </Card>

            <Card className="p-6">
              <h2 className="text-lg font-semibold mb-4">Plan Features</h2>
              <ul className="space-y-3">
                {(currentPlan?.features && currentPlan.features.length > 0
                  ? currentPlan.features
                  : ['Credits included each month', 'Module access per plan limits', 'Email support'])
                  .map((feature) => (
                    <li key={feature} className="flex items-center gap-2 text-gray-700 dark:text-gray-300">
                      <CheckCircle className="w-5 h-5 text-green-600" />
                      {feature}
                    </li>
                  ))}
              </ul>
            </Card>
          </div>
        )}

        {/* Upgrade/Downgrade Tab */}
        {activeTab === 'upgrade' && (
          <div className="space-y-6">
            <div className="mb-4">
              <h2 className="text-xl font-semibold mb-2">Available Plans</h2>
              <p className="text-gray-600 dark:text-gray-400">Choose the plan that best fits your needs</p>
            </div>

            {hasPaymentMethods ? (
              <div className="p-4 border border-gray-200 dark:border-gray-700 rounded-lg">
                <div className="text-sm font-medium text-gray-700 dark:text-gray-200 mb-2">Select payment method</div>
                <div className="flex flex-wrap gap-3">
                  {paymentMethods.map((method) => (
                    <label
                      key={method.id}
                      className={`px-3 py-2 rounded-lg border cursor-pointer text-sm ${
                        selectedPaymentMethod === (method.type || method.id)
                          ? 'border-blue-500 bg-blue-50 dark:bg-blue-900/30'
                          : 'border-gray-200 dark:border-gray-700'
                      }`}
                    >
                      <input
                        type="radio"
                        className="sr-only"
                        checked={selectedPaymentMethod === (method.type || method.id)}
                        onChange={() => setSelectedPaymentMethod(method.type || method.id)}
                      />
                      <div className="font-semibold text-gray-900 dark:text-white">{method.display_name}</div>
                      <div className="text-xs text-gray-500 dark:text-gray-400">{method.type}</div>
                    </label>
                  ))}
                </div>
              </div>
            ) : (
              <div className="p-4 rounded-lg border border-amber-200 bg-amber-50 text-amber-800 dark:border-amber-800 dark:bg-amber-900/20 dark:text-amber-200">
                No payment methods available. Please contact support or add one from the Payment Methods tab.
              </div>
            )}
            
            <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6">
              {plans.map((plan) => {
                const isCurrent = plan.id === currentPlanId;
                const price = plan.price ? `$${plan.price}/${plan.interval || 'month'}` : 'Custom';
                return (
                  <Card key={plan.id} className="p-6 relative border border-gray-200 dark:border-gray-700">
                    <div className="mb-4">
                      <h3 className="text-lg font-semibold">{plan.name}</h3>
                      <div className="text-3xl font-bold text-gray-900 dark:text-white mt-2">{price}</div>
                      <div className="text-sm text-gray-500">{plan.description || 'Standard plan'}</div>
                    </div>
                    <div className="space-y-3 mb-6">
                      {(plan.features && plan.features.length > 0 ? plan.features : ['Monthly credits included', 'Module access per plan', 'Email support']).map((feature) => (
                        <div key={feature} className="flex items-center gap-2 text-sm">
                          <CheckCircle className="w-4 h-4 text-green-600" />
                          <span>{feature}</span>
                        </div>
                      ))}
                    </div>
                    <Button
                      variant={isCurrent ? 'outline' : 'primary'}
                      tone="brand"
                      fullWidth
                      disabled={isCurrent || planLoadingId === plan.id}
                      onClick={() => handleSelectPlan(plan.id)}
                    >
                      {planLoadingId === plan.id
                        ? 'Updating...'
                        : isCurrent
                          ? 'Current Plan'
                          : 'Select Plan'}
                    </Button>
                  </Card>
                );
              })}
              {plans.length === 0 && (
                <div className="col-span-3 text-center py-12 text-gray-500">
                  No plans available. Please contact support.
                </div>
              )}
            </div>

            <Card className="p-6 bg-blue-50 dark:bg-blue-900/20 border-blue-200 dark:border-blue-800">
              <h3 className="font-semibold text-blue-900 dark:text-blue-100 mb-2">Plan Change Policy</h3>
              <ul className="space-y-2 text-sm text-blue-800 dark:text-blue-200">
                <li>• Upgrades take effect immediately and you'll be charged a prorated amount</li>
                <li>• Downgrades take effect at the end of your current billing period</li>
                <li>• Unused credits from your current plan will carry over</li>
                <li>• You can cancel your subscription at any time</li>
              </ul>
            </Card>
          </div>
        )}

        {/* Credits Overview Tab */}
        {activeTab === 'credits' && (
          <div className="space-y-6">
            <div className="grid grid-cols-1 md:grid-cols-3 gap-6">
              <Card className="p-6">
                <div className="text-sm text-gray-600 dark:text-gray-400 mb-1">Current Balance</div>
                <div className="text-3xl font-bold text-blue-600 dark:text-blue-400">
                  {creditBalance?.credits.toLocaleString() || 0}
                </div>
                <div className="text-sm text-gray-500 mt-2">credits available</div>
              </Card>
              <Card className="p-6">
                <div className="text-sm text-gray-600 dark:text-gray-400 mb-1">Used This Month</div>
                <div className="text-3xl font-bold text-red-600 dark:text-red-400">
                  {creditBalance?.credits_used_this_month.toLocaleString() || 0}
                </div>
                <div className="text-sm text-gray-500 mt-2">credits consumed</div>
              </Card>
              <Card className="p-6">
                <div className="text-sm text-gray-600 dark:text-gray-400 mb-1">Monthly Included</div>
                <div className="text-3xl font-bold text-green-600 dark:text-green-400">
                  {creditBalance?.plan_credits_per_month.toLocaleString() || 0}
                </div>
                <div className="text-sm text-gray-500 mt-2">from your plan</div>
              </Card>
            </div>

            <Card className="p-6">
              <h2 className="text-lg font-semibold mb-4">Credit Usage Summary</h2>
              <div className="space-y-2">
                <div className="flex justify-between items-center">
                  <span className="text-gray-700 dark:text-gray-300">Remaining Credits</span>
                  <span className="font-semibold">{creditBalance?.credits_remaining.toLocaleString() || 0}</span>
                </div>
                <div className="w-full bg-gray-200 dark:bg-gray-700 rounded-full h-2">
                  <div 
                    className="bg-blue-600 h-2 rounded-full" 
                    style={{ 
                      width: creditBalance?.credits 
                        ? `${Math.min((creditBalance.credits / (creditBalance.plan_credits_per_month || 1)) * 100, 100)}%` 
                        : '0%' 
                    }}
                  ></div>
                </div>
              </div>
            </Card>
          </div>
        )}

        {/* Purchase Credits Tab */}
        {activeTab === 'purchase' && (
          <div className="space-y-6">
            {hasPaymentMethods ? (
              <div className="p-4 border border-gray-200 dark:border-gray-700 rounded-lg">
                <div className="text-sm font-medium text-gray-700 dark:text-gray-200 mb-2">Select payment method</div>
                <div className="flex flex-wrap gap-3">
                  {paymentMethods.map((method) => (
                    <label
                      key={method.id}
                      className={`px-3 py-2 rounded-lg border cursor-pointer text-sm ${
                        selectedPaymentMethod === (method.type || method.id)
                          ? 'border-blue-500 bg-blue-50 dark:bg-blue-900/30'
                          : 'border-gray-200 dark:border-gray-700'
                      }`}
                    >
                      <input
                        type="radio"
                        className="sr-only"
                        checked={selectedPaymentMethod === (method.type || method.id)}
                        onChange={() => setSelectedPaymentMethod(method.type || method.id)}
                      />
                      <div className="font-semibold text-gray-900 dark:text-white">{method.display_name}</div>
                      <div className="text-xs text-gray-500 dark:text-gray-400">{method.type}</div>
                    </label>
                  ))}
                </div>
              </div>
            ) : (
              <div className="p-4 rounded-lg border border-amber-200 bg-amber-50 text-amber-800 dark:border-amber-800 dark:bg-amber-900/20 dark:text-amber-200">
                No payment methods available. Please contact support or add one from the Payment Methods tab.
              </div>
            )}

            <Card className="p-6">
              <h2 className="text-lg font-semibold mb-4">Credit Packages</h2>
              <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6">
                {packages.map((pkg) => (
                  <div key={pkg.id} className="border border-gray-200 dark:border-gray-700 rounded-lg p-6 hover:border-blue-500 transition-colors">
                    <div className="text-lg font-semibold text-gray-900 dark:text-white">{pkg.name}</div>
                    <div className="text-3xl font-bold text-blue-600 dark:text-blue-400 mt-2">
                      {pkg.credits.toLocaleString()} <span className="text-sm text-gray-500">credits</span>
                    </div>
                    <div className="text-2xl font-semibold text-gray-900 dark:text-white mt-4">
                      ${pkg.price}
                    </div>
                    {pkg.description && (
                      <div className="text-sm text-gray-600 dark:text-gray-400 mt-2">{pkg.description}</div>
                    )}
                    <Button 
                      variant="primary"
                      tone="brand"
                      onClick={() => handlePurchase(pkg.id)}
                      fullWidth
                      className="mt-6"
                      disabled={purchaseLoadingId === pkg.id || (!hasPaymentMethods && paymentMethods.length > 0)}
                    >
                      {purchaseLoadingId === pkg.id ? 'Processing...' : 'Purchase'}
                    </Button>
                  </div>
                ))}
                {packages.length === 0 && (
                  <div className="col-span-3 text-center py-12 text-gray-500">
                    No credit packages available at this time
                  </div>
                )}
              </div>
            </Card>
          </div>
        )}

        {/* Billing History Tab */}
        {activeTab === 'invoices' && (
          <Card className="overflow-hidden">
            <div className="overflow-x-auto">
              <table className="w-full">
                <thead className="bg-gray-50 dark:bg-gray-800 border-b border-gray-200 dark:border-gray-700">
                  <tr>
                    <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                      Invoice
                    </th>
                    <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                      Date
                    </th>
                    <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                      Amount
                    </th>
                    <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                      Status
                    </th>
                    <th className="px-6 py-3 text-right text-xs font-medium text-gray-500 uppercase tracking-wider">
                      Actions
                    </th>
                  </tr>
                </thead>
                <tbody className="divide-y divide-gray-200 dark:divide-gray-700">
                  {invoices.length === 0 ? (
                    <tr>
                      <td colSpan={5} className="px-6 py-8 text-center text-gray-500">
                        <FileText className="w-12 h-12 mx-auto mb-2 text-gray-400" />
                        No invoices yet
                      </td>
                    </tr>
                  ) : (
                    invoices.map((invoice) => (
                      <tr key={invoice.id} className="hover:bg-gray-50 dark:hover:bg-gray-800">
                        <td className="px-6 py-4 font-medium">{invoice.invoice_number}</td>
                        <td className="px-6 py-4 text-sm text-gray-600 dark:text-gray-400">
                          {new Date(invoice.created_at).toLocaleDateString()}
                        </td>
                        <td className="px-6 py-4 font-semibold">${invoice.total_amount}</td>
                        <td className="px-6 py-4">
                          <Badge 
                            variant="light" 
                            color={invoice.status === 'paid' ? 'success' : 'warning'}
                          >
                            {invoice.status}
                          </Badge>
                        </td>
                        <td className="px-6 py-4 text-right">
                          <Button 
                            variant="ghost" 
                            tone="brand"
                            size="sm"
                            startIcon={<Download className="w-4 h-4" />}
                            className="ml-auto"
                            onClick={() => handleDownloadInvoice(invoice.id)}
                          >
                            Download
                          </Button>
                        </td>
                      </tr>
                    ))
                  )}
                </tbody>
              </table>
            </div>
          </Card>
        )}

        {/* Payments Tab */}
        {activeTab === 'payments' && (
          <div className="space-y-6">
            <Card className="p-6">
              <div className="flex items-center justify-between mb-4">
                <div>
                  <h2 className="text-lg font-semibold">Payments</h2>
                  <p className="text-sm text-gray-600 dark:text-gray-400">Recent payments and manual submissions</p>
                </div>
              </div>
              <div className="overflow-x-auto">
                <table className="w-full">
                  <thead className="bg-gray-50 dark:bg-gray-800 border-b border-gray-200 dark:border-gray-700">
                    <tr>
                      <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Invoice</th>
                      <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Amount</th>
                      <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Method</th>
                      <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Status</th>
                      <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">Date</th>
                    </tr>
                  </thead>
                  <tbody className="divide-y divide-gray-200 dark:divide-gray-700">
                    {payments.length === 0 ? (
                      <tr>
                        <td colSpan={5} className="px-6 py-8 text-center text-gray-500">
                          No payments yet
                        </td>
                      </tr>
                    ) : (
                      payments.map((payment) => (
                        <tr key={payment.id} className="hover:bg-gray-50 dark:hover:bg-gray-800">
                          <td className="px-6 py-4 text-sm font-medium text-gray-900 dark:text-white">
                            {payment.invoice_number || payment.invoice_id || '-'}
                          </td>
                          <td className="px-6 py-4 text-sm text-gray-900 dark:text-white">
                            ${payment.amount}
                          </td>
                          <td className="px-6 py-4 text-sm text-gray-600 dark:text-gray-400">
                            {payment.payment_method}
                          </td>
                          <td className="px-6 py-4">
                            <Badge 
                              variant="light" 
                              color={
                                payment.status === 'succeeded' || payment.status === 'completed'
                                  ? 'success'
                                  : payment.status === 'pending' || payment.status === 'processing'
                                  ? 'warning'
                                  : 'error'
                              }
                            >
                              {payment.status}
                            </Badge>
                          </td>
                          <td className="px-6 py-4 text-sm text-gray-600 dark:text-gray-400">
                            {new Date(payment.created_at).toLocaleDateString()}
                          </td>
                        </tr>
                      ))
                    )}
                  </tbody>
                </table>
              </div>
            </Card>

            <Card className="p-6">
              <h3 className="text-lg font-semibold mb-4">Submit Manual Payment</h3>
              <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
                <div>
                  <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">Invoice ID (optional)</label>
                  <input
                    type="number"
                    value={manualPayment.invoice_id}
                    onChange={(e) => setManualPayment((p) => ({ ...p, invoice_id: e.target.value }))}
                    className="w-full px-4 py-2 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 text-gray-900 dark:text-white"
                    placeholder="Invoice ID"
                  />
                </div>
                <div>
                  <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">Amount</label>
                  <input
                    type="text"
                    value={manualPayment.amount}
                    onChange={(e) => setManualPayment((p) => ({ ...p, amount: e.target.value }))}
                    className="w-full px-4 py-2 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 text-gray-900 dark:text-white"
                    placeholder="e.g., 99.00"
                  />
                </div>
                <div>
                  <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">Payment Method</label>
                  <input
                    type="text"
                    value={manualPayment.payment_method}
                    onChange={(e) => setManualPayment((p) => ({ ...p, payment_method: e.target.value }))}
                    className="w-full px-4 py-2 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 text-gray-900 dark:text-white"
                    placeholder="bank_transfer / local_wallet / manual"
                  />
                </div>
                <div>
                  <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">Reference</label>
                  <input
                    type="text"
                    value={manualPayment.reference}
                    onChange={(e) => setManualPayment((p) => ({ ...p, reference: e.target.value }))}
                    className="w-full px-4 py-2 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 text-gray-900 dark:text-white"
                    placeholder="Reference or transaction id"
                  />
                </div>
                <div className="md:col-span-2">
                  <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">Notes</label>
                  <textarea
                    value={manualPayment.notes}
                    onChange={(e) => setManualPayment((p) => ({ ...p, notes: e.target.value }))}
                    className="w-full px-4 py-2 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 text-gray-900 dark:text-white"
                    placeholder="Optional notes"
                  />
                </div>
              </div>
              <div className="mt-4 flex justify-end">
                <Button variant="primary" tone="brand" onClick={handleSubmitManualPayment}>
                  Submit Manual Payment
                </Button>
              </div>
            </Card>
          </div>
        )}

        {/* Payment Methods Tab */}
        {activeTab === 'payment-methods' && (
          <div className="space-y-6">
            <Card className="p-6">
              <div className="flex items-center justify-between mb-4">
                <h2 className="text-lg font-semibold">Payment Methods</h2>
              </div>
              <div className="grid grid-cols-1 md:grid-cols-3 gap-4 mb-4">
                <div>
                  <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">Type</label>
                  <select
                    value={newPaymentMethod.type}
                    onChange={(e) => setNewPaymentMethod((p) => ({ ...p, type: e.target.value }))}
                    className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 text-gray-900 dark:text-white"
                  >
                    <option value="bank_transfer">Bank Transfer</option>
                    <option value="local_wallet">Local Wallet</option>
                    <option value="manual">Manual</option>
                  </select>
                </div>
                <div>
                  <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">Display Name</label>
                  <input
                    type="text"
                    value={newPaymentMethod.display_name}
                    onChange={(e) => setNewPaymentMethod((p) => ({ ...p, display_name: e.target.value }))}
                    className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 text-gray-900 dark:text-white"
                    placeholder="e.g., Bank Transfer (USD)"
                  />
                </div>
                <div>
                  <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">Instructions (optional)</label>
                  <input
                    type="text"
                    value={newPaymentMethod.instructions}
                    onChange={(e) => setNewPaymentMethod((p) => ({ ...p, instructions: e.target.value }))}
                    className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg bg-white dark:bg-gray-800 text-gray-900 dark:text-white"
                    placeholder="Where to send payment"
                  />
                </div>
              </div>
              <div className="mb-4">
                <Button variant="primary" tone="brand" onClick={handleAddPaymentMethod}>
                  Add Payment Method
                </Button>
              </div>
              <div className="space-y-4">
                {paymentMethods.map((method) => (
                  <div key={method.id} className="border border-gray-200 dark:border-gray-700 rounded-lg p-4 flex items-center justify-between">
                    <div className="flex items-center gap-4">
                      <CreditCard className="w-8 h-8 text-gray-400" />
                      <div>
                        <div className="font-medium text-gray-900 dark:text-white">{method.display_name}</div>
                        <div className="text-sm text-gray-600 dark:text-gray-400">{method.type}</div>
                        {method.instructions && (
                          <div className="text-xs text-gray-500 dark:text-gray-400 mt-1">{method.instructions}</div>
                        )}
                      </div>
                    </div>
                    <div className="flex items-center gap-2">
                      {method.is_enabled && (
                        <Badge variant="light" color="success">Active</Badge>
                      )}
                      {method.is_default ? (
                        <Badge variant="light" color="info">Default</Badge>
                      ) : (
                        <Button variant="outline" size="sm" onClick={() => handleSetDefaultPaymentMethod(method.id)}>
                          Make Default
                        </Button>
                      )}
                      <Button variant="outline" size="sm" tone="neutral" onClick={() => handleRemovePaymentMethod(method.id)}>
                        Remove
                      </Button>
                    </div>
                  </div>
                ))}
                {paymentMethods.length === 0 && (
                  <div className="text-center py-12 text-gray-500">
                    No payment methods configured
                  </div>
                )}
              </div>
            </Card>
          </div>
        )}
      </div>
    </div>
  );
}
