'use client';

import React, { useState, useMemo } from 'react';
import {
  User,
  Building,
  Mail,
  Lock,
  Save,
  Bell,
  Camera,
  RotateCcw,
  Check,
  X,
  Eye,
  EyeOff,
  Shield,
  AlertCircle
} from 'lucide-react';

type TabType = 'profile' | 'password' | 'notifications';

interface NotificationSettings {
  emailNotifications: boolean;
  dealUpdates: boolean;
  weeklyDigest: boolean;
  marketingEmails: boolean;
  smsAlerts: boolean;
}

export default function SettingsPage() {
  const [activeTab, setActiveTab] = useState<TabType>('profile');
  const [showCurrentPassword, setShowCurrentPassword] = useState(false);
  const [showNewPassword, setShowNewPassword] = useState(false);
  const [showConfirmPassword, setShowConfirmPassword] = useState(false);
  const [profileSaveStatus, setProfileSaveStatus] = useState<'idle' | 'saving' | 'success' | 'error'>('idle');
  const [passwordSaveStatus, setPasswordSaveStatus] = useState<'idle' | 'saving' | 'success' | 'error'>('idle');
  const [notificationSaveStatus, setNotificationSaveStatus] = useState<'idle' | 'saving' | 'success' | 'error'>('idle');

  // Simulated current user data
  const initialProfileData = {
    firstName: 'John',
    lastName: 'Doe',
    email: 'john.doe@example.com',
    brokerage: 'Premier Real Estate',
    phone: '(555) 123-4567',
  };

  const [formData, setFormData] = useState({
    ...initialProfileData,
    currentPassword: '',
    newPassword: '',
    confirmPassword: '',
  });

  const [notifications, setNotifications] = useState<NotificationSettings>({
    emailNotifications: true,
    dealUpdates: true,
    weeklyDigest: false,
    marketingEmails: false,
    smsAlerts: true,
  });

  const handleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
    const { name, value } = e.target;
    setFormData((prev) => ({ ...prev, [name]: value }));
  };

  const handleNotificationChange = (key: keyof NotificationSettings) => {
    setNotifications((prev) => ({ ...prev, [key]: !prev[key] }));
  };

  const resetProfileForm = () => {
    setFormData((prev) => ({
      ...prev,
      ...initialProfileData,
    }));
    setProfileSaveStatus('idle');
  };

  const resetPasswordForm = () => {
    setFormData((prev) => ({
      ...prev,
      currentPassword: '',
      newPassword: '',
      confirmPassword: '',
    }));
    setPasswordSaveStatus('idle');
  };

  const handleProfileSubmit = (e: React.FormEvent) => {
    e.preventDefault();
    setProfileSaveStatus('saving');

    // Simulate API call
    setTimeout(() => {
      setProfileSaveStatus('success');
      setTimeout(() => setProfileSaveStatus('idle'), 3000);
    }, 1000);
  };

  const handlePasswordSubmit = (e: React.FormEvent) => {
    e.preventDefault();
    if (formData.newPassword !== formData.confirmPassword) {
      setPasswordSaveStatus('error');
      return;
    }
    setPasswordSaveStatus('saving');

    // Simulate API call
    setTimeout(() => {
      setPasswordSaveStatus('success');
      resetPasswordForm();
      setTimeout(() => setPasswordSaveStatus('idle'), 3000);
    }, 1000);
  };

  const handleNotificationSubmit = (e: React.FormEvent) => {
    e.preventDefault();
    setNotificationSaveStatus('saving');

    // Simulate API call
    setTimeout(() => {
      setNotificationSaveStatus('success');
      setTimeout(() => setNotificationSaveStatus('idle'), 3000);
    }, 1000);
  };

  // Password strength calculation
  const passwordStrength = useMemo(() => {
    const password = formData.newPassword;
    if (!password) return { score: 0, label: '', color: '' };

    let score = 0;
    if (password.length >= 8) score++;
    if (password.length >= 12) score++;
    if (/[a-z]/.test(password) && /[A-Z]/.test(password)) score++;
    if (/\d/.test(password)) score++;
    if (/[^a-zA-Z0-9]/.test(password)) score++;

    if (score <= 1) return { score: 1, label: 'Weak', color: 'bg-red-500' };
    if (score <= 2) return { score: 2, label: 'Fair', color: 'bg-orange-500' };
    if (score <= 3) return { score: 3, label: 'Good', color: 'bg-yellow-500' };
    if (score <= 4) return { score: 4, label: 'Strong', color: 'bg-green-500' };
    return { score: 5, label: 'Very Strong', color: 'bg-emerald-500' };
  }, [formData.newPassword]);

  const tabs: { id: TabType; label: string; icon: React.ReactNode }[] = [
    { id: 'profile', label: 'Profile', icon: <User className="w-4 h-4" /> },
    { id: 'password', label: 'Password', icon: <Lock className="w-4 h-4" /> },
    { id: 'notifications', label: 'Notifications', icon: <Bell className="w-4 h-4" /> },
  ];

  const SaveStatusBadge = ({ status }: { status: 'idle' | 'saving' | 'success' | 'error' }) => {
    if (status === 'idle') return null;

    return (
      <div className={`flex items-center gap-2 px-4 py-2 rounded-lg text-sm font-medium transition-all ${
        status === 'saving' ? 'bg-blue-50 text-blue-700' :
        status === 'success' ? 'bg-green-50 text-green-700' :
        'bg-red-50 text-red-700'
      }`}>
        {status === 'saving' && (
          <>
            <div className="w-4 h-4 border-2 border-blue-700 border-t-transparent rounded-full animate-spin" />
            Saving changes...
          </>
        )}
        {status === 'success' && (
          <>
            <Check className="w-4 h-4" />
            Changes saved successfully!
          </>
        )}
        {status === 'error' && (
          <>
            <AlertCircle className="w-4 h-4" />
            Failed to save. Please try again.
          </>
        )}
      </div>
    );
  };

  return (
    <div className="space-y-8 max-w-4xl mx-auto">
      <div className="mb-8">
        <h1 className="text-3xl font-bold text-gray-800">Settings</h1>
        <p className="text-gray-500 mt-2">Manage your account and preferences</p>
      </div>

      {/* Tab Navigation */}
      <div className="flex flex-wrap gap-3 mb-8 p-1 bg-gray-100 rounded-xl w-fit">
        {tabs.map((tab) => (
          <button
            key={tab.id}
            onClick={() => setActiveTab(tab.id)}
            className={`flex items-center gap-2 px-5 py-3 rounded-lg font-medium transition-all ${
              activeTab === tab.id
                ? 'bg-white text-indigo-600 shadow-sm'
                : 'text-gray-600 hover:text-gray-800 hover:bg-gray-50'
            }`}
          >
            {tab.icon}
            {tab.label}
          </button>
        ))}
      </div>

      {/* Profile Tab */}
      {activeTab === 'profile' && (
        <div className="clay-card shadow-lg border border-border/50 p-8">
          <div className="flex items-center gap-3 mb-6">
            <div className="clay-icon-btn bg-indigo-100">
              <User className="w-5 h-5 text-indigo-600" />
            </div>
            <div>
              <h2 className="text-xl font-bold text-gray-800 mb-1">Profile Information</h2>
              <p className="text-sm text-gray-500">Update your personal details and photo</p>
            </div>
          </div>

          {/* Profile Photo Upload */}
          <div className="flex items-center gap-8 mb-8 pb-8 border-b border-gray-200">
            <div className="relative p-2">
              <div className="w-24 h-24 rounded-full bg-gradient-to-br from-indigo-400 to-purple-500 flex items-center justify-center text-white text-2xl font-bold">
                {formData.firstName.charAt(0)}{formData.lastName.charAt(0)}
              </div>
              <button className="absolute bottom-2 right-2 w-8 h-8 bg-white rounded-full shadow-lg flex items-center justify-center border border-gray-200 hover:bg-gray-50 transition-colors">
                <Camera className="w-4 h-4 text-gray-600" />
              </button>
            </div>
            <div>
              <h3 className="font-semibold text-gray-800">Profile Photo</h3>
              <p className="text-sm text-gray-500 mb-3">JPG, PNG or GIF. Max size 2MB.</p>
              <button className="text-sm text-indigo-600 hover:text-indigo-700 font-medium">
                Upload new photo
              </button>
            </div>
          </div>

          <form onSubmit={handleProfileSubmit} className="space-y-6">
            <div className="grid grid-cols-1 md:grid-cols-2 gap-6">
              <div>
                <label htmlFor="firstName" className="block text-sm font-semibold text-gray-700 mb-2">
                  First Name
                </label>
                <input
                  type="text"
                  id="firstName"
                  name="firstName"
                  value={formData.firstName}
                  onChange={handleChange}
                  placeholder="Enter your first name"
                  className="clay-input h-14 py-4 border border-gray-200 w-full"
                />
              </div>
              <div>
                <label htmlFor="lastName" className="block text-sm font-semibold text-gray-700 mb-2">
                  Last Name
                </label>
                <input
                  type="text"
                  id="lastName"
                  name="lastName"
                  value={formData.lastName}
                  onChange={handleChange}
                  placeholder="Enter your last name"
                  className="clay-input h-14 py-4 border border-gray-200 w-full"
                />
              </div>
            </div>

            <div>
              <label htmlFor="email" className="block text-sm font-semibold text-gray-700 mb-2">
                <span className="flex items-center gap-2">
                  <Mail className="w-4 h-4 text-gray-400" />
                  Email Address
                </span>
              </label>
              <input
                type="email"
                id="email"
                name="email"
                value={formData.email}
                onChange={handleChange}
                placeholder="Enter your email address"
                className="clay-input h-14 py-4 border border-gray-200 w-full"
              />
            </div>

            <div>
              <label htmlFor="phone" className="block text-sm font-semibold text-gray-700 mb-2">
                Phone Number
              </label>
              <input
                type="tel"
                id="phone"
                name="phone"
                value={formData.phone}
                onChange={handleChange}
                placeholder="Enter your phone number"
                className="clay-input h-14 py-4 border border-gray-200 w-full"
              />
            </div>

            <div>
              <label htmlFor="brokerage" className="block text-sm font-semibold text-gray-700 mb-2">
                <span className="flex items-center gap-2">
                  <Building className="w-4 h-4 text-gray-400" />
                  Brokerage Name
                </span>
              </label>
              <input
                type="text"
                id="brokerage"
                name="brokerage"
                value={formData.brokerage}
                onChange={handleChange}
                placeholder="Enter your brokerage name"
                className="clay-input h-14 py-4 border border-gray-200 w-full"
              />
            </div>

            <div className="flex flex-col sm:flex-row items-start sm:items-center justify-between gap-4 pt-6 mt-8 border-t border-gray-200">
              <SaveStatusBadge status={profileSaveStatus} />
              <div className="flex gap-4">
                <button
                  type="button"
                  onClick={resetProfileForm}
                  className="clay-btn flex items-center gap-2 px-6 py-3 text-gray-600 hover:text-gray-800 border border-gray-300 rounded-xl"
                >
                  <RotateCcw className="w-4 h-4" />
                  Reset
                </button>
                <button
                  type="submit"
                  className="clay-btn-primary flex items-center gap-2 px-6 py-3"
                  disabled={profileSaveStatus === 'saving'}
                >
                  <Save className="w-4 h-4" />
                  Save Profile
                </button>
              </div>
            </div>
          </form>
        </div>
      )}

      {/* Password Tab */}
      {activeTab === 'password' && (
        <div className="clay-card shadow-lg border border-border/50 p-8">
          <div className="flex items-center gap-3 mb-6">
            <div className="clay-icon-btn bg-amber-100">
              <Lock className="w-5 h-5 text-amber-600" />
            </div>
            <div>
              <h2 className="text-xl font-bold text-gray-800 mb-1">Change Password</h2>
              <p className="text-sm text-gray-500">Update your security credentials</p>
            </div>
          </div>

          {/* Security Tips */}
          <div className="bg-blue-50 border border-blue-200 rounded-xl p-4 mb-8">
            <div className="flex items-start gap-3">
              <Shield className="w-5 h-5 text-blue-600 mt-0.5" />
              <div>
                <h4 className="font-semibold text-blue-800 text-sm">Password Security Tips</h4>
                <ul className="text-sm text-blue-700 mt-1 space-y-1">
                  <li>Use at least 12 characters with uppercase, lowercase, numbers, and symbols</li>
                  <li>Avoid using personal information or common words</li>
                  <li>Do not reuse passwords from other accounts</li>
                </ul>
              </div>
            </div>
          </div>

          <form onSubmit={handlePasswordSubmit} className="space-y-6">
            <div>
              <label htmlFor="currentPassword" className="block text-sm font-semibold text-gray-700 mb-2">
                Current Password
              </label>
              <div className="relative">
                <input
                  type={showCurrentPassword ? 'text' : 'password'}
                  id="currentPassword"
                  name="currentPassword"
                  value={formData.currentPassword}
                  onChange={handleChange}
                  placeholder="Enter your current password"
                  className="clay-input h-14 py-4 border border-gray-200 w-full pr-12"
                />
                <button
                  type="button"
                  onClick={() => setShowCurrentPassword(!showCurrentPassword)}
                  className="absolute right-4 top-1/2 -translate-y-1/2 text-gray-400 hover:text-gray-600"
                >
                  {showCurrentPassword ? <EyeOff className="w-5 h-5" /> : <Eye className="w-5 h-5" />}
                </button>
              </div>
            </div>

            <div>
              <label htmlFor="newPassword" className="block text-sm font-semibold text-gray-700 mb-2">
                New Password
              </label>
              <div className="relative">
                <input
                  type={showNewPassword ? 'text' : 'password'}
                  id="newPassword"
                  name="newPassword"
                  value={formData.newPassword}
                  onChange={handleChange}
                  placeholder="Enter new password"
                  className="clay-input h-14 py-4 border border-gray-200 w-full pr-12"
                />
                <button
                  type="button"
                  onClick={() => setShowNewPassword(!showNewPassword)}
                  className="absolute right-4 top-1/2 -translate-y-1/2 text-gray-400 hover:text-gray-600"
                >
                  {showNewPassword ? <EyeOff className="w-5 h-5" /> : <Eye className="w-5 h-5" />}
                </button>
              </div>

              {/* Password Strength Indicator */}
              {formData.newPassword && (
                <div className="mt-3">
                  <div className="flex items-center justify-between mb-2">
                    <span className="text-xs text-gray-500">Password Strength</span>
                    <span className={`text-xs font-medium ${
                      passwordStrength.score <= 2 ? 'text-red-600' :
                      passwordStrength.score <= 3 ? 'text-yellow-600' : 'text-green-600'
                    }`}>
                      {passwordStrength.label}
                    </span>
                  </div>
                  <div className="flex gap-1">
                    {[1, 2, 3, 4, 5].map((level) => (
                      <div
                        key={level}
                        className={`h-1.5 flex-1 rounded-full transition-colors ${
                          level <= passwordStrength.score ? passwordStrength.color : 'bg-gray-200'
                        }`}
                      />
                    ))}
                  </div>
                </div>
              )}
            </div>

            <div>
              <label htmlFor="confirmPassword" className="block text-sm font-semibold text-gray-700 mb-2">
                Confirm New Password
              </label>
              <div className="relative">
                <input
                  type={showConfirmPassword ? 'text' : 'password'}
                  id="confirmPassword"
                  name="confirmPassword"
                  value={formData.confirmPassword}
                  onChange={handleChange}
                  placeholder="Confirm new password"
                  className={`clay-input h-14 py-4 border w-full pr-12 ${
                    formData.confirmPassword && formData.newPassword !== formData.confirmPassword
                      ? 'border-red-300 focus:border-red-500'
                      : 'border-gray-200'
                  }`}
                />
                <button
                  type="button"
                  onClick={() => setShowConfirmPassword(!showConfirmPassword)}
                  className="absolute right-4 top-1/2 -translate-y-1/2 text-gray-400 hover:text-gray-600"
                >
                  {showConfirmPassword ? <EyeOff className="w-5 h-5" /> : <Eye className="w-5 h-5" />}
                </button>
              </div>
              {formData.confirmPassword && formData.newPassword !== formData.confirmPassword && (
                <p className="text-red-500 text-sm mt-2 flex items-center gap-1">
                  <X className="w-4 h-4" />
                  Passwords do not match
                </p>
              )}
              {formData.confirmPassword && formData.newPassword === formData.confirmPassword && formData.newPassword && (
                <p className="text-green-500 text-sm mt-2 flex items-center gap-1">
                  <Check className="w-4 h-4" />
                  Passwords match
                </p>
              )}
            </div>

            <div className="flex flex-col sm:flex-row items-start sm:items-center justify-between gap-4 pt-6 mt-8 border-t border-gray-200">
              <SaveStatusBadge status={passwordSaveStatus} />
              <div className="flex gap-4">
                <button
                  type="button"
                  onClick={resetPasswordForm}
                  className="clay-btn flex items-center gap-2 px-6 py-3 text-gray-600 hover:text-gray-800 border border-gray-300 rounded-xl"
                >
                  <X className="w-4 h-4" />
                  Cancel
                </button>
                <button
                  type="submit"
                  className="clay-btn-primary flex items-center gap-2 px-6 py-3"
                  disabled={passwordSaveStatus === 'saving' || !formData.currentPassword || !formData.newPassword || formData.newPassword !== formData.confirmPassword}
                >
                  <Lock className="w-4 h-4" />
                  Update Password
                </button>
              </div>
            </div>
          </form>
        </div>
      )}

      {/* Notifications Tab */}
      {activeTab === 'notifications' && (
        <div className="clay-card shadow-lg border border-border/50 p-8">
          <div className="flex items-center gap-3 mb-6">
            <div className="clay-icon-btn bg-purple-100">
              <Bell className="w-5 h-5 text-purple-600" />
            </div>
            <div>
              <h2 className="text-xl font-bold text-gray-800 mb-1">Notification Preferences</h2>
              <p className="text-sm text-gray-500">Choose how you want to be notified</p>
            </div>
          </div>

          <form onSubmit={handleNotificationSubmit} className="space-y-2">
            {[
              { key: 'emailNotifications', label: 'Email Notifications', description: 'Receive important updates via email' },
              { key: 'dealUpdates', label: 'Deal Updates', description: 'Get notified when deals change status' },
              { key: 'weeklyDigest', label: 'Weekly Digest', description: 'Receive a summary of your activity each week' },
              { key: 'marketingEmails', label: 'Marketing Communications', description: 'Stay updated on new features and tips' },
              { key: 'smsAlerts', label: 'SMS Alerts', description: 'Receive text messages for urgent notifications' },
            ].map((item) => (
              <div
                key={item.key}
                className="flex items-center justify-between py-5 px-4 gap-6 rounded-xl hover:bg-gray-50 transition-colors"
              >
                <div>
                  <h4 className="font-medium text-gray-800 mb-1">{item.label}</h4>
                  <p className="text-sm text-gray-500">{item.description}</p>
                </div>
                <button
                  type="button"
                  onClick={() => handleNotificationChange(item.key as keyof NotificationSettings)}
                  className={`relative w-12 h-7 rounded-full transition-colors flex-shrink-0 ${
                    notifications[item.key as keyof NotificationSettings]
                      ? 'bg-indigo-600'
                      : 'bg-gray-300'
                  }`}
                >
                  <div
                    className={`absolute top-1 w-5 h-5 bg-white rounded-full shadow transition-transform ${
                      notifications[item.key as keyof NotificationSettings]
                        ? 'translate-x-6'
                        : 'translate-x-1'
                    }`}
                  />
                </button>
              </div>
            ))}

            <div className="flex flex-col sm:flex-row items-start sm:items-center justify-between gap-4 pt-6 mt-8 border-t border-gray-200">
              <SaveStatusBadge status={notificationSaveStatus} />
              <button
                type="submit"
                className="clay-btn-primary flex items-center gap-2 px-6 py-3"
                disabled={notificationSaveStatus === 'saving'}
              >
                <Save className="w-4 h-4" />
                Save Preferences
              </button>
            </div>
          </form>
        </div>
      )}
    </div>
  );
}