'use client';

import { useState, useEffect, useCallback } from 'react';
import { useSession } from 'next-auth/react';
import api from '@/services/api';

interface NotificationSetting {
  id: string;
  label: string;
  description: string;
  enabled: boolean;
}

interface NotificationsFormProps {
  onSave?: (data: {
    emailNotifications: NotificationSetting[];
    pushNotifications: NotificationSetting[];
  }) => void;
}

// Default notification settings (all disabled by default)
const DEFAULT_EMAIL_NOTIFICATIONS: NotificationSetting[] = [
  {
    id: 'new_leads',
    label: 'New Leads',
    description: 'Get notified when you receive new leads',
    enabled: false,
  },
  {
    id: 'messages',
    label: 'Messages',
    description: 'Get notified when you receive new messages',
    enabled: false,
  },
  {
    id: 'connection_requests',
    label: 'Connection Requests',
    description: 'Get notified about new connection requests',
    enabled: false,
  },
  {
    id: 'property_updates',
    label: 'Property Updates',
    description: 'Get notified about property status changes',
    enabled: false,
  },
  {
    id: 'marketing',
    label: 'Marketing & Promotions',
    description: 'Receive marketing emails and promotions',
    enabled: false,
  },
];

const DEFAULT_PUSH_NOTIFICATIONS: NotificationSetting[] = [
  {
    id: 'push_messages',
    label: 'Messages',
    description: 'Push notifications for new messages',
    enabled: false,
  },
  {
    id: 'push_leads',
    label: 'New Leads',
    description: 'Push notifications for new leads',
    enabled: false,
  },
  {
    id: 'push_reminders',
    label: 'Reminders',
    description: 'Push notifications for scheduled reminders',
    enabled: false,
  },
];

export function NotificationsForm({ onSave }: NotificationsFormProps) {
  const { data: session } = useSession();
  const [isLoading, setIsLoading] = useState(true);
  const [isSaving, setIsSaving] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const [success, setSuccess] = useState<string | null>(null);

  const [emailNotifications, setEmailNotifications] = useState<NotificationSetting[]>(DEFAULT_EMAIL_NOTIFICATIONS);
  const [pushNotifications, setPushNotifications] = useState<NotificationSetting[]>(DEFAULT_PUSH_NOTIFICATIONS);

  // Fetch saved preferences on mount
  const fetchPreferences = useCallback(async () => {
    if (!session) return;

    try {
      setIsLoading(true);
      const role = (session?.user as any)?.role;
      const endpoint = role === 'AGENT' ? '/agents/preferences/notifications' : '/users/preferences/notifications';

      const response = await api.get(endpoint);
      const savedPrefs = response.data?.data || response.data || {};

      // Merge saved preferences with defaults
      if (savedPrefs.email) {
        setEmailNotifications((prev) =>
          prev.map((item) => ({
            ...item,
            enabled: savedPrefs.email[item.id] ?? item.enabled,
          }))
        );
      }

      if (savedPrefs.push) {
        setPushNotifications((prev) =>
          prev.map((item) => ({
            ...item,
            enabled: savedPrefs.push[item.id] ?? item.enabled,
          }))
        );
      }
    } catch (err) {
      // If no saved preferences, use defaults (all disabled)
      console.log('No saved notification preferences found, using defaults');
    } finally {
      setIsLoading(false);
    }
  }, [session]);

  useEffect(() => {
    fetchPreferences();
  }, [fetchPreferences]);

  const toggleEmailNotification = (id: string) => {
    setEmailNotifications((prev) =>
      prev.map((item) =>
        item.id === id ? { ...item, enabled: !item.enabled } : item
      )
    );
  };

  const togglePushNotification = (id: string) => {
    setPushNotifications((prev) =>
      prev.map((item) =>
        item.id === id ? { ...item, enabled: !item.enabled } : item
      )
    );
  };

  const handleSave = async () => {
    setIsSaving(true);
    setError(null);
    setSuccess(null);

    try {
      const role = (session?.user as any)?.role;
      const endpoint = role === 'AGENT' ? '/agents/preferences/notifications' : '/users/preferences/notifications';

      // Transform settings to API format
      const preferences = {
        email: emailNotifications.reduce((acc, item) => ({ ...acc, [item.id]: item.enabled }), {}),
        push: pushNotifications.reduce((acc, item) => ({ ...acc, [item.id]: item.enabled }), {}),
      };

      await api.put(endpoint, preferences);

      setSuccess('Notification preferences saved successfully!');

      if (onSave) {
        onSave({ emailNotifications, pushNotifications });
      }

      // Clear success message after 3 seconds
      setTimeout(() => setSuccess(null), 3000);
    } catch (err: unknown) {
      const error = err as { response?: { data?: { message?: string } } };
      setError(error.response?.data?.message || 'Failed to save notification preferences. Please try again.');
    } finally {
      setIsSaving(false);
    }
  };

  const ToggleSwitch = ({
    enabled,
    onToggle,
  }: {
    enabled: boolean;
    onToggle: () => void;
  }) => (
    <button
      onClick={onToggle}
      className={`relative w-[44px] h-[24px] rounded-full transition-colors cursor-pointer ${
        enabled ? 'bg-[#e58625]' : 'bg-[#00293D]/20'
      }`}
    >
      <div
        className={`absolute top-[2px] w-[20px] h-[20px] rounded-full bg-white shadow transition-transform ${
          enabled ? 'translate-x-[22px]' : 'translate-x-[2px]'
        }`}
      />
    </button>
  );

  if (isLoading) {
    return (
      <div className="flex items-center justify-center py-12">
        <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-[#e58625]"></div>
      </div>
    );
  }

  return (
    <>
      {/* Error Message */}
      {error && (
        <div className="mb-4 p-3 bg-red-50 border border-red-200 rounded-[10px] text-red-700 text-[13px] font-serif">
          {error}
        </div>
      )}

      {/* Success Message */}
      {success && (
        <div className="mb-4 p-3 bg-green-50 border border-green-200 rounded-[10px] text-green-700 text-[13px] font-serif">
          {success}
        </div>
      )}

      {/* Email Notifications */}
      <div className="border border-[#00293d]/10 rounded-[15px] bg-white p-6 mb-4">
        <div className="mb-6">
          <h2 className="font-fractul font-bold text-[16px] text-[#00293D] mb-2">
            Email Notifications
          </h2>
          <p className="font-serif text-[12px] text-[#00293D]/60">
            Manage your email notification preferences
          </p>
        </div>

        <div className="space-y-4">
          {emailNotifications.map((item) => (
            <div
              key={item.id}
              className="flex items-center justify-between py-3 border-b border-[#00293d]/10 last:border-0"
            >
              <div>
                <h3 className="font-serif font-medium text-[14px] text-[#00293D]">
                  {item.label}
                </h3>
                <p className="font-serif text-[12px] text-[#00293D]/60">
                  {item.description}
                </p>
              </div>
              <ToggleSwitch
                enabled={item.enabled}
                onToggle={() => toggleEmailNotification(item.id)}
              />
            </div>
          ))}
        </div>
      </div>

      {/* Push Notifications */}
      <div className="border border-[#00293d]/10 rounded-[15px] bg-white p-6 mb-4">
        <div className="mb-6">
          <h2 className="font-fractul font-bold text-[16px] text-[#00293D] mb-2">
            Push Notifications
          </h2>
          <p className="font-serif text-[12px] text-[#00293D]/60">
            Manage your push notification preferences
          </p>
        </div>

        <div className="space-y-4">
          {pushNotifications.map((item) => (
            <div
              key={item.id}
              className="flex items-center justify-between py-3 border-b border-[#00293d]/10 last:border-0"
            >
              <div>
                <h3 className="font-serif font-medium text-[14px] text-[#00293D]">
                  {item.label}
                </h3>
                <p className="font-serif text-[12px] text-[#00293D]/60">
                  {item.description}
                </p>
              </div>
              <ToggleSwitch
                enabled={item.enabled}
                onToggle={() => togglePushNotification(item.id)}
              />
            </div>
          ))}
        </div>
      </div>

      {/* Save Button */}
      <div className="flex justify-end">
        <button
          onClick={handleSave}
          disabled={isSaving}
          className="px-8 py-3 bg-[#e58625] text-white rounded-[15px] font-fractul font-medium text-[14px] hover:bg-[#d47920] transition-colors disabled:opacity-50 disabled:cursor-not-allowed"
        >
          {isSaving ? 'Saving...' : 'Save Changes'}
        </button>
      </div>
    </>
  );
}