import { useState } from 'react';
import { Ban, UserCheck } from 'lucide-react';
import { useForm } from 'react-hook-form';
import { zodResolver } from '@hookform/resolvers/zod';
import * as z from 'zod';
import { Button } from '@/components/ui/button';
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
  DialogTrigger,
} from '@/components/ui/dialog';
import {
  Form,
  FormControl,
  FormDescription,
  FormField,
  FormItem,
  FormLabel,
  FormMessage,
} from '@/components/ui/form';
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from '@/components/ui/select';
import { Textarea } from '@/components/ui/textarea';
import { Alert, AlertDescription } from '@/components/ui/alert';

const BAN_REASONS = [
  { value: 'spam', label: 'Spam or advertising' },
  { value: 'harassment', label: 'Harassment or bullying' },
  { value: 'inappropriate_content', label: 'Inappropriate content' },
  { value: 'violation_tos', label: 'Terms of Service violation' },
  { value: 'abuse', label: 'Abuse of platform features' },
  { value: 'fake_info', label: 'Posting false information' },
  { value: 'copyright', label: 'Copyright infringement' },
  { value: 'multiple_accounts', label: 'Multiple account abuse' },
  { value: 'other', label: 'Other (specify below)' }
] as const;

const BAN_DURATIONS = [
  { value: '1', label: '1 Day', days: 1 },
  { value: '7', label: '7 Days (1 Week)', days: 7 },
  { value: '30', label: '30 Days (1 Month)', days: 30 },
  { value: '90', label: '90 Days (3 Months)', days: 90 },
  { value: 'permanent', label: 'Permanent', days: null }
] as const;

const banFormSchema = z.object({
  reason_type: z.enum([
    'spam', 
    'harassment', 
    'inappropriate_content', 
    'violation_tos', 
    'abuse', 
    'fake_info', 
    'copyright', 
    'multiple_accounts', 
    'other'
  ]),
  custom_reason: z.string().max(500).optional(),
  duration: z.enum(['1', '7', '30', '90', 'permanent'])
}).refine(
  (data) => data.reason_type !== 'other' || (data.custom_reason && data.custom_reason.trim().length > 0),
  {
    message: "Please provide a custom reason",
    path: ["custom_reason"]
  }
);

type BanFormValues = z.infer<typeof banFormSchema>;

interface BanUserDialogProps {
  profile: {
    user_id: string;
    username: string;
    banned: boolean;
  };
  onBanComplete: () => void;
  onBanUser: (userId: string, ban: boolean, reason?: string, expiresAt?: Date | null) => Promise<void>;
  disabled?: boolean;
}

export function BanUserDialog({ profile, onBanComplete, onBanUser, disabled }: BanUserDialogProps) {
  const [open, setOpen] = useState(false);
  const [isSubmitting, setIsSubmitting] = useState(false);

  const form = useForm<BanFormValues>({
    resolver: zodResolver(banFormSchema),
    defaultValues: {
      reason_type: 'violation_tos',
      custom_reason: '',
      duration: '7'
    }
  });

  const watchReasonType = form.watch('reason_type');
  const watchDuration = form.watch('duration');

  const onSubmit = async (values: BanFormValues) => {
    setIsSubmitting(true);
    try {
      // Construct the ban reason
      let banReason: string;
      if (values.reason_type === 'other' && values.custom_reason) {
        banReason = values.custom_reason.trim();
      } else {
        const selectedReason = BAN_REASONS.find(r => r.value === values.reason_type);
        banReason = selectedReason?.label || 'Policy violation';
      }

      // Calculate expiration date
      let expiresAt: Date | null = null;
      if (values.duration !== 'permanent') {
        const durationConfig = BAN_DURATIONS.find(d => d.value === values.duration);
        if (durationConfig?.days) {
          expiresAt = new Date();
          expiresAt.setDate(expiresAt.getDate() + durationConfig.days);
        }
      }

      await onBanUser(profile.user_id, true, banReason, expiresAt);
      setOpen(false);
      form.reset();
      onBanComplete();
    } catch (error) {
      // Error handling is done by the parent component
    } finally {
      setIsSubmitting(false);
    }
  };

  const handleUnban = async () => {
    setIsSubmitting(true);
    try {
      await onBanUser(profile.user_id, false);
      setOpen(false);
      onBanComplete();
    } catch (error) {
      // Error handling is done by the parent component
    } finally {
      setIsSubmitting(false);
    }
  };

  // For unbanning, use simpler dialog
  if (profile.banned) {
    return (
      <Dialog open={open} onOpenChange={setOpen}>
        <DialogTrigger asChild>
          <Button variant="outline" size="sm" disabled={disabled}>
            <UserCheck className="w-4 h-4 mr-2" />
            Unban
          </Button>
        </DialogTrigger>
        <DialogContent>
          <DialogHeader>
            <DialogTitle>Unban User</DialogTitle>
            <DialogDescription>
              Are you sure you want to unban @{profile.username}? They will be able to access the application again.
            </DialogDescription>
          </DialogHeader>
          <DialogFooter>
            <Button variant="outline" onClick={() => setOpen(false)} disabled={isSubmitting}>
              Cancel
            </Button>
            <Button onClick={handleUnban} disabled={isSubmitting}>
              {isSubmitting ? 'Unbanning...' : 'Unban User'}
            </Button>
          </DialogFooter>
        </DialogContent>
      </Dialog>
    );
  }

  // For banning, use detailed form
  return (
    <Dialog open={open} onOpenChange={setOpen}>
      <DialogTrigger asChild>
        <Button variant="destructive" size="sm" disabled={disabled}>
          <Ban className="w-4 h-4 mr-2" />
          Ban
        </Button>
      </DialogTrigger>
      <DialogContent className="max-w-2xl max-h-[90vh] overflow-y-auto">
        <DialogHeader>
          <DialogTitle>Ban User</DialogTitle>
          <DialogDescription>
            Ban @{profile.username} from accessing the application. You must provide a reason and duration.
          </DialogDescription>
        </DialogHeader>

        <Form {...form}>
          <form onSubmit={form.handleSubmit(onSubmit)} className="space-y-6">
            <FormField
              control={form.control}
              name="reason_type"
              render={({ field }) => (
                <FormItem>
                  <FormLabel>Ban Reason</FormLabel>
                  <Select onValueChange={field.onChange} defaultValue={field.value}>
                    <FormControl>
                      <SelectTrigger>
                        <SelectValue placeholder="Select a reason" />
                      </SelectTrigger>
                    </FormControl>
                    <SelectContent>
                      {BAN_REASONS.map((reason) => (
                        <SelectItem key={reason.value} value={reason.value}>
                          {reason.label}
                        </SelectItem>
                      ))}
                    </SelectContent>
                  </Select>
                  <FormDescription>
                    Choose the primary reason for this ban
                  </FormDescription>
                  <FormMessage />
                </FormItem>
              )}
            />

            {watchReasonType === 'other' && (
              <FormField
                control={form.control}
                name="custom_reason"
                render={({ field }) => (
                  <FormItem>
                    <FormLabel>Custom Reason</FormLabel>
                    <FormControl>
                      <Textarea
                        placeholder="Provide a detailed reason for the ban..."
                        className="min-h-[100px] resize-none"
                        maxLength={500}
                        {...field}
                      />
                    </FormControl>
                    <FormDescription>
                      {field.value?.length || 0}/500 characters
                    </FormDescription>
                    <FormMessage />
                  </FormItem>
                )}
              />
            )}

            <FormField
              control={form.control}
              name="duration"
              render={({ field }) => (
                <FormItem>
                  <FormLabel>Ban Duration</FormLabel>
                  <Select onValueChange={field.onChange} defaultValue={field.value}>
                    <FormControl>
                      <SelectTrigger>
                        <SelectValue placeholder="Select duration" />
                      </SelectTrigger>
                    </FormControl>
                    <SelectContent>
                      {BAN_DURATIONS.map((duration) => (
                        <SelectItem key={duration.value} value={duration.value}>
                          {duration.label}
                        </SelectItem>
                      ))}
                    </SelectContent>
                  </Select>
                  <FormDescription>
                    How long should this ban last?
                  </FormDescription>
                  <FormMessage />
                </FormItem>
              )}
            />

            <Alert>
              <AlertDescription>
                <strong>User will see:</strong> Your account has been suspended. Reason:{' '}
                {watchReasonType === 'other' && form.getValues('custom_reason') 
                  ? form.getValues('custom_reason')
                  : BAN_REASONS.find(r => r.value === watchReasonType)?.label || 'Policy violation'}
                .{' '}
                {watchDuration === 'permanent' 
                  ? 'This is a permanent ban.'
                  : `This ban will expire in ${BAN_DURATIONS.find(d => d.value === watchDuration)?.label.toLowerCase()}.`}
              </AlertDescription>
            </Alert>

            <DialogFooter>
              <Button 
                type="button" 
                variant="outline" 
                onClick={() => setOpen(false)} 
                disabled={isSubmitting}
              >
                Cancel
              </Button>
              <Button type="submit" variant="destructive" disabled={isSubmitting}>
                {isSubmitting ? 'Banning...' : 'Ban User'}
              </Button>
            </DialogFooter>
          </form>
        </Form>
      </DialogContent>
    </Dialog>
  );
}