import React, { useState } from 'react';
import { useNavigate } from 'react-router-dom';
import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
import { api } from '@/lib/api';
import { SettingsLayout } from '../components/SettingsLayout';
import { SettingsCard } from '../components/SettingsCard';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { __ } from '@/lib/i18n';
import { ArrowLeft, RefreshCw, Upload, Plus, Trash2, Facebook, Twitter, Instagram, Linkedin, Youtube, Globe, MessageCircle, Music, Send, AtSign } from 'lucide-react';
import { toast } from 'sonner';
import { openWPMediaLogo } from '@/lib/wp-media';
import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select';

interface SocialLink {
  platform: string;
  url: string;
}

interface EmailSettings {
  primary_color: string;
  secondary_color: string;
  hero_gradient_start: string;
  hero_gradient_end: string;
  hero_text_color: string;
  button_text_color: string;
  body_bg_color: string;
  social_icon_color: string;
  logo_url: string;
  header_text: string;
  footer_text: string;
  social_links: SocialLink[];
}

export default function EmailCustomization() {
  const navigate = useNavigate();
  const queryClient = useQueryClient();

  // Fetch email settings
  const { data: settings, isLoading } = useQuery({
    queryKey: ['email-settings'],
    queryFn: () => api.get('/notifications/email-settings'),
    placeholderData: {
      primary_color: '#7f54b3',
      secondary_color: '#7f54b3',
      hero_gradient_start: '#667eea',
      hero_gradient_end: '#764ba2',
      hero_text_color: '#ffffff',
      button_text_color: '#ffffff',
      body_bg_color: '#f8f8f8',
      social_icon_color: 'white',
      logo_url: '',
      header_text: '',
      footer_text: '',
      social_links: [],
    },
  });

  const [formData, setFormData] = useState<EmailSettings>(settings || {
    primary_color: '#7f54b3',
    secondary_color: '#7f54b3',
    hero_gradient_start: '#667eea',
    hero_gradient_end: '#764ba2',
    hero_text_color: '#ffffff',
    button_text_color: '#ffffff',
    body_bg_color: '#f8f8f8',
    social_icon_color: 'white',
    logo_url: '',
    header_text: '',
    footer_text: '',
    social_links: [],
  });

  // Update form when settings load
  React.useEffect(() => {
    if (settings) {
      setFormData(settings);
    }
  }, [settings]);

  const saveMutation = useMutation({
    mutationFn: async () => {
      return api.post('/notifications/email-settings', formData);
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['email-settings'] });
      toast.success(__('Email settings saved successfully'));
    },
    onError: (error: any) => {
      toast.error(error.message || __('Failed to save email settings'));
    },
  });

  const resetMutation = useMutation({
    mutationFn: async () => {
      return api.del('/notifications/email-settings');
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: ['email-settings'] });
      toast.success(__('Email settings reset to defaults'));
    },
    onError: (error: any) => {
      toast.error(error.message || __('Failed to reset email settings'));
    },
  });

  const handleSave = async () => {
    return new Promise<void>((resolve, reject) => {
      saveMutation.mutate(undefined, {
        onSuccess: () => resolve(),
        onError: () => reject(),
      });
    });
  };

  const handleReset = () => {
    if (!confirm(__('Are you sure you want to reset all email customization to defaults?'))) return;
    resetMutation.mutate();
  };

  const handleChange = (field: keyof EmailSettings, value: string) => {
    setFormData(prev => ({ ...prev, [field]: value }));
  };

  const handleLogoSelect = () => {
    openWPMediaLogo((media) => {
      if (media && media.url) {
        handleChange('logo_url', media.url);
      }
    });
  };

  const addSocialLink = () => {
    setFormData(prev => ({
      ...prev,
      social_links: [...prev.social_links, { platform: 'facebook', url: '' }],
    }));
  };

  const removeSocialLink = (index: number) => {
    setFormData(prev => ({
      ...prev,
      social_links: prev.social_links.filter((_, i) => i !== index),
    }));
  };

  const updateSocialLink = (index: number, field: 'platform' | 'url', value: string) => {
    setFormData(prev => ({
      ...prev,
      social_links: prev.social_links.map((link, i) =>
        i === index ? { ...link, [field]: value } : link
      ),
    }));
  };

  const getSocialIcon = (platform: string) => {
    const icons: Record<string, any> = {
      facebook: Facebook,
      x: AtSign,
      instagram: Instagram,
      linkedin: Linkedin,
      youtube: Youtube,
      discord: MessageCircle,
      spotify: Music,
      telegram: Send,
      whatsapp: MessageCircle,
      threads: AtSign,
      website: Globe,
    };
    const Icon = icons[platform] || Globe;
    return <Icon className="h-4 w-4" />;
  };

  if (isLoading) {
    return (
      <SettingsLayout
        title={__('Email Customization')}
        description={__('Loading...')}
      >
        <div className="flex items-center justify-center py-12">
          <RefreshCw className="h-6 w-6 animate-spin text-muted-foreground" />
        </div>
      </SettingsLayout>
    );
  }

  return (
    <SettingsLayout
      title={__('Email Customization')}
      description={__('Customize the appearance and branding of all email templates')}
      onSave={handleSave}
      saveLabel={__('Save Settings')}
      isLoading={saveMutation.isPending}
      action={
        <div className="flex items-center gap-2">
          <Button
            variant="ghost"
            size="sm"
            onClick={() => navigate('/settings/notifications')}
            className="gap-2"
          >
            <ArrowLeft className="h-4 w-4" />
            <span className="hidden sm:inline">{__('Back')}</span>
          </Button>
          <Button
            variant="outline"
            size="sm"
            onClick={handleReset}
            disabled={resetMutation.isPending}
          >
            {resetMutation.isPending ? (
              <RefreshCw className="h-4 w-4 animate-spin" />
            ) : (
              __('Reset to Defaults')
            )}
          </Button>
        </div>
      }
    >
      <div className="space-y-6">
        {/* Brand Colors */}
        <SettingsCard
          title={__('Brand Colors')}
          description={__('Set your primary and secondary brand colors for buttons and accents')}
        >
          <div className="grid gap-6 sm:grid-cols-2">
            <div className="space-y-2">
              <Label htmlFor="primary_color">{__('Primary Color')}</Label>
              <div className="flex gap-2">
                <Input
                  id="primary_color"
                  type="color"
                  value={formData.primary_color}
                  onChange={(e) => handleChange('primary_color', e.target.value)}
                  className="w-20 h-10 p-1 cursor-pointer"
                />
                <Input
                  type="text"
                  value={formData.primary_color}
                  onChange={(e) => handleChange('primary_color', e.target.value)}
                  placeholder="#7f54b3"
                  className="flex-1"
                />
              </div>
              <p className="text-xs text-muted-foreground">
                {__('Used for primary buttons and main accents')}
              </p>
            </div>

            <div className="space-y-2">
              <Label htmlFor="secondary_color">{__('Secondary Color')}</Label>
              <div className="flex gap-2">
                <Input
                  id="secondary_color"
                  type="color"
                  value={formData.secondary_color}
                  onChange={(e) => handleChange('secondary_color', e.target.value)}
                  className="w-20 h-10 p-1 cursor-pointer"
                />
                <Input
                  type="text"
                  value={formData.secondary_color}
                  onChange={(e) => handleChange('secondary_color', e.target.value)}
                  placeholder="#7f54b3"
                  className="flex-1"
                />
              </div>
              <p className="text-xs text-muted-foreground">
                {__('Used for outline buttons and borders')}
              </p>
            </div>
          </div>
        </SettingsCard>

        {/* Hero Card Gradient */}
        <SettingsCard
          title={__('Hero Card Gradient')}
          description={__('Customize the gradient colors for hero/success card backgrounds')}
        >
          <div className="grid gap-6 sm:grid-cols-2">
            <div className="space-y-2">
              <Label htmlFor="hero_gradient_start">{__('Gradient Start')}</Label>
              <div className="flex gap-2">
                <Input
                  id="hero_gradient_start"
                  type="color"
                  value={formData.hero_gradient_start}
                  onChange={(e) => handleChange('hero_gradient_start', e.target.value)}
                  className="w-20 h-10 p-1 cursor-pointer"
                />
                <Input
                  type="text"
                  value={formData.hero_gradient_start}
                  onChange={(e) => handleChange('hero_gradient_start', e.target.value)}
                  placeholder="#667eea"
                  className="flex-1"
                />
              </div>
            </div>

            <div className="space-y-2">
              <Label htmlFor="hero_gradient_end">{__('Gradient End')}</Label>
              <div className="flex gap-2">
                <Input
                  id="hero_gradient_end"
                  type="color"
                  value={formData.hero_gradient_end}
                  onChange={(e) => handleChange('hero_gradient_end', e.target.value)}
                  className="w-20 h-10 p-1 cursor-pointer"
                />
                <Input
                  type="text"
                  value={formData.hero_gradient_end}
                  onChange={(e) => handleChange('hero_gradient_end', e.target.value)}
                  placeholder="#764ba2"
                  className="flex-1"
                />
              </div>
            </div>
          </div>

          <div className="space-y-2">
            <Label htmlFor="hero_text_color">{__('Text Color')}</Label>
            <div className="flex gap-2">
              <Input
                id="hero_text_color"
                type="color"
                value={formData.hero_text_color}
                onChange={(e) => handleChange('hero_text_color', e.target.value)}
                className="w-20 h-10 p-1 cursor-pointer"
              />
              <Input
                type="text"
                value={formData.hero_text_color}
                onChange={(e) => handleChange('hero_text_color', e.target.value)}
                placeholder="#ffffff"
                className="flex-1"
              />
            </div>
            <p className="text-xs text-muted-foreground">
              {__('Text and heading color for hero cards (usually white)')}
            </p>
          </div>

          {/* Preview */}
          <div className="mt-4 p-6 rounded-lg text-center" style={{
            background: `linear-gradient(135deg, ${formData.hero_gradient_start} 0%, ${formData.hero_gradient_end} 100%)`
          }}>
            <h3 className="text-xl font-bold mb-2" style={{ color: formData.hero_text_color }}>{__('Preview')}</h3>
            <p className="text-sm opacity-90" style={{ color: formData.hero_text_color }}>{__('This is how your hero cards will look')}</p>
          </div>
        </SettingsCard>

        {/* Button Styling */}
        <SettingsCard
          title={__('Button Styling')}
          description={__('Customize button text color and appearance')}
        >
          <div className="space-y-4">
            <div className="space-y-2">
              <Label htmlFor="button_text_color">{__('Button Text Color')}</Label>
              <div className="flex gap-2">
                <Input
                  id="button_text_color"
                  type="color"
                  value={formData.button_text_color}
                  onChange={(e) => handleChange('button_text_color', e.target.value)}
                  className="w-20 h-10 p-1 cursor-pointer"
                />
                <Input
                  type="text"
                  value={formData.button_text_color}
                  onChange={(e) => handleChange('button_text_color', e.target.value)}
                  placeholder="#ffffff"
                  className="flex-1"
                />
              </div>
              <p className="text-xs text-muted-foreground">
                {__('Text color for buttons (usually white for dark buttons)')}
              </p>
            </div>

            {/* Button Preview */}
            <div className="flex gap-3 flex-wrap">
              <button
                className="px-6 py-3 rounded-lg font-medium"
                style={{
                  backgroundColor: formData.primary_color,
                  color: formData.button_text_color,
                }}
              >
                {__('Primary Button')}
              </button>
              <button
                className="px-6 py-3 rounded-lg font-medium border-2"
                style={{
                  borderColor: formData.secondary_color,
                  color: formData.secondary_color,
                  backgroundColor: 'transparent',
                }}
              >
                {__('Secondary Button')}
              </button>
            </div>
          </div>
        </SettingsCard>

        {/* Email Background & Social Icons */}
        <SettingsCard
          title={__('Email Background & Social Icons')}
          description={__('Customize email background and social icon colors')}
        >
          <div className="grid gap-6 sm:grid-cols-2">
            <div className="space-y-2">
              <Label htmlFor="body_bg_color">{__('Email Background Color')}</Label>
              <div className="flex gap-2">
                <Input
                  id="body_bg_color"
                  type="color"
                  value={formData.body_bg_color}
                  onChange={(e) => handleChange('body_bg_color', e.target.value)}
                  className="w-20 h-10 p-1 cursor-pointer"
                />
                <Input
                  type="text"
                  value={formData.body_bg_color}
                  onChange={(e) => handleChange('body_bg_color', e.target.value)}
                  placeholder="#f8f8f8"
                  className="flex-1"
                />
              </div>
              <p className="text-xs text-muted-foreground">
                {__('Background color for the email body')}
              </p>
            </div>

            <div className="space-y-2">
              <Label htmlFor="social_icon_color">{__('Social Icon Color')}</Label>
              <Select
                value={formData.social_icon_color}
                onValueChange={(value) => handleChange('social_icon_color', value)}
              >
                <SelectTrigger>
                  <SelectValue />
                </SelectTrigger>
                <SelectContent>
                  <SelectItem value="white">{__('White Icons')}</SelectItem>
                  <SelectItem value="black">{__('Black Icons')}</SelectItem>
                </SelectContent>
              </Select>
              <p className="text-xs text-muted-foreground">
                {__('Choose white icons for dark backgrounds, black for light backgrounds')}
              </p>
            </div>
          </div>
        </SettingsCard>

        {/* Logo & Branding */}
        <SettingsCard
          title={__('Logo & Branding')}
          description={__('Add your logo and custom header/footer text')}
        >
          <div className="space-y-4">
            <div className="space-y-2">
              <Label htmlFor="logo_url">{__('Logo URL')}</Label>
              <div className="flex gap-2">
                <Input
                  id="logo_url"
                  type="url"
                  value={formData.logo_url}
                  onChange={(e) => handleChange('logo_url', e.target.value)}
                  placeholder="https://example.com/logo.png"
                  className="flex-1"
                />
                <Button
                  type="button"
                  variant="outline"
                  onClick={handleLogoSelect}
                  className="gap-2"
                >
                  <Upload className="h-4 w-4" />
                  {__('Select')}
                </Button>
              </div>
              <p className="text-xs text-muted-foreground">
                {__('Full URL to your logo image (recommended: 200x60px)')}
              </p>
              {formData.logo_url && (
                <div className="mt-2 p-4 border rounded-lg bg-muted/30">
                  <img
                    src={formData.logo_url}
                    alt="Logo preview"
                    className="max-h-16 object-contain"
                  />
                </div>
              )}
            </div>

            <div className="space-y-2">
              <Label htmlFor="header_text">{__('Header Text')}</Label>
              <Input
                id="header_text"
                type="text"
                value={formData.header_text}
                onChange={(e) => handleChange('header_text', e.target.value)}
                placeholder={__('Your Store Name')}
              />
              <p className="text-xs text-muted-foreground">
                {__('Text shown in email header (leave empty to use store name)')}
              </p>
            </div>

            <div className="space-y-2">
              <Label htmlFor="footer_text">{__('Footer Text')}</Label>
              <Input
                id="footer_text"
                type="text"
                value={formData.footer_text}
                onChange={(e) => handleChange('footer_text', e.target.value)}
                placeholder={__('© {current_year} Your Store. All rights reserved.')}
              />
              <p className="text-xs text-muted-foreground">
                {__('Text shown in email footer. Use {current_year} for dynamic year.')}
              </p>
            </div>

            {/* Social Links */}
            <div className="space-y-3">
              <div className="flex items-center justify-between">
                <Label>{__('Social Links')}</Label>
                <Button
                  type="button"
                  variant="outline"
                  size="sm"
                  onClick={addSocialLink}
                  className="gap-2"
                >
                  <Plus className="h-4 w-4" />
                  {__('Add Social Link')}
                </Button>
              </div>
              
              {formData.social_links.length === 0 ? (
                <p className="text-sm text-muted-foreground">
                  {__('No social links added. Click "Add Social Link" to get started.')}
                </p>
              ) : (
                <div className="space-y-2">
                  {formData.social_links.map((link, index) => (
                    <div key={index} className="flex gap-2 items-start p-3 border rounded-lg">
                      <div className="flex-1 grid grid-cols-2 gap-2">
                        <div>
                          <Select
                            value={link.platform}
                            onValueChange={(value) => updateSocialLink(index, 'platform', value)}
                          >
                            <SelectTrigger className="h-9">
                              <SelectValue />
                            </SelectTrigger>
                            <SelectContent>
                              <SelectItem value="facebook">
                                <div className="flex items-center gap-2">
                                  <Facebook className="h-4 w-4" />
                                  Facebook
                                </div>
                              </SelectItem>
                              <SelectItem value="x">
                                <div className="flex items-center gap-2">
                                  <AtSign className="h-4 w-4" />
                                  X (Twitter)
                                </div>
                              </SelectItem>
                              <SelectItem value="instagram">
                                <div className="flex items-center gap-2">
                                  <Instagram className="h-4 w-4" />
                                  Instagram
                                </div>
                              </SelectItem>
                              <SelectItem value="linkedin">
                                <div className="flex items-center gap-2">
                                  <Linkedin className="h-4 w-4" />
                                  LinkedIn
                                </div>
                              </SelectItem>
                              <SelectItem value="youtube">
                                <div className="flex items-center gap-2">
                                  <Youtube className="h-4 w-4" />
                                  YouTube
                                </div>
                              </SelectItem>
                              <SelectItem value="discord">
                                <div className="flex items-center gap-2">
                                  <MessageCircle className="h-4 w-4" />
                                  Discord
                                </div>
                              </SelectItem>
                              <SelectItem value="spotify">
                                <div className="flex items-center gap-2">
                                  <Music className="h-4 w-4" />
                                  Spotify
                                </div>
                              </SelectItem>
                              <SelectItem value="telegram">
                                <div className="flex items-center gap-2">
                                  <Send className="h-4 w-4" />
                                  Telegram
                                </div>
                              </SelectItem>
                              <SelectItem value="whatsapp">
                                <div className="flex items-center gap-2">
                                  <MessageCircle className="h-4 w-4" />
                                  WhatsApp
                                </div>
                              </SelectItem>
                              <SelectItem value="threads">
                                <div className="flex items-center gap-2">
                                  <AtSign className="h-4 w-4" />
                                  Threads
                                </div>
                              </SelectItem>
                              <SelectItem value="website">
                                <div className="flex items-center gap-2">
                                  <Globe className="h-4 w-4" />
                                  Website
                                </div>
                              </SelectItem>
                            </SelectContent>
                          </Select>
                        </div>
                        <Input
                          type="url"
                          value={link.url}
                          onChange={(e) => updateSocialLink(index, 'url', e.target.value)}
                          placeholder="https://..."
                          className="h-9"
                        />
                      </div>
                      <Button
                        type="button"
                        variant="ghost"
                        size="sm"
                        onClick={() => removeSocialLink(index)}
                        className="h-9 w-9 p-0 text-destructive hover:text-destructive"
                      >
                        <Trash2 className="h-4 w-4" />
                      </Button>
                    </div>
                  ))}
                </div>
              )}
              <p className="text-xs text-muted-foreground">
                {__('Social links will appear as icons in the email footer')}
              </p>
            </div>
          </div>
        </SettingsCard>

        {/* Info Box */}
        <div className="bg-blue-50 dark:bg-blue-950/20 border border-blue-200 dark:border-blue-800 rounded-lg p-4">
          <p className="text-sm text-blue-900 dark:text-blue-100">
            <strong>{__('Note:')}</strong> {__('These settings will apply to all email templates. Individual templates can still override specific content, but colors and branding will be consistent across all emails.')}
          </p>
        </div>
      </div>
    </SettingsLayout>
  );
}