import { useState } from 'react';
import { nip19 } from 'nostr-tools';
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogHeader,
  DialogTitle,
} from '@/components/ui/dialog';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { useTradeAttestation, TRADE_METHODS, type TradeMethod } from '@/hooks/useTradeAttestations';
import { useMarkListingSold } from '@/hooks/useMarkListingSold';
import { useToast } from '@/hooks/useToast';
import { cn } from '@/lib/utils';
import { Check, Loader2 } from 'lucide-react';
import type { NostrEvent } from '@nostrify/nostrify';

function resolvePubkey(input: string): string | null {
  const t = input.trim();
  if (/^[a-f0-9]{64}$/i.test(t)) return t.toLowerCase();
  if (t.startsWith('npub1')) {
    try {
      const decoded = nip19.decode(t);
      return decoded.type === 'npub' ? decoded.data : null;
    } catch {
      return null;
    }
  }
  return null;
}

/**
 * Seller's "close the deal" flow: mark the listing sold AND publish a trade
 * attestation (kind 31871) naming the buyer, so both sides can build
 * reputation. Payment method is self-reported — the app can't see cash/trade
 * deals and never treats it as proof of payment.
 */
export function MarkSoldDialog({
  open,
  onOpenChange,
  event,
  listing,
}: {
  open: boolean;
  onOpenChange: (open: boolean) => void;
  event: NostrEvent;
  listing: { pubkey: string; identifier: string };
}) {
  const { publishTrade, isPending: publishing } = useTradeAttestation();
  const { markSold, isPending: marking } = useMarkListingSold();
  const { toast } = useToast();

  const [buyer, setBuyer] = useState('');
  const [method, setMethod] = useState<TradeMethod>('cash');
  const [amount, setAmount] = useState('');

  const buyerPubkey = resolvePubkey(buyer);
  const busy = publishing || marking;

  const submit = async () => {
    if (!buyerPubkey) {
      toast({ title: 'Enter the buyer’s npub', variant: 'destructive' });
      return;
    }
    try {
      await markSold(event);
      await publishTrade({
        listing,
        role: 'sold',
        counterparty: buyerPubkey,
        method,
        amountSats: amount.trim() ? Number(amount) : undefined,
      });
      toast({
        title: 'Deal closed 🎉',
        description: 'Listing marked sold and the trade was published for reputation.',
      });
      onOpenChange(false);
      setBuyer('');
      setAmount('');
    } catch (e) {
      toast({
        title: 'Could not close the deal',
        description: e instanceof Error ? e.message : 'Something went wrong.',
        variant: 'destructive',
      });
    }
  };

  return (
    <Dialog open={open} onOpenChange={onOpenChange}>
      <DialogContent className="mx-4 max-w-[calc(100vw-2rem)] border-2 border-[#ccff00]/40 bg-black sm:max-w-md">
        <DialogHeader>
          <DialogTitle className="text-white">Close the deal</DialogTitle>
          <DialogDescription className="text-sm text-gray-400">
            Marks this listing sold and records a signed trade attestation for you and the buyer.
          </DialogDescription>
        </DialogHeader>

        <div className="space-y-4">
          <div className="space-y-2">
            <Label htmlFor="buyer" className="flex items-center gap-2 text-xs uppercase tracking-wide text-gray-400">
              Buyer&apos;s npub
              {buyerPubkey && <Check className="h-3.5 w-3.5 text-[#ccff00]" />}
            </Label>
            <Input
              id="buyer"
              value={buyer}
              onChange={(e) => setBuyer(e.target.value)}
              placeholder="npub1…"
              className="h-11 border-gray-700 bg-gray-900 font-mono text-xs text-white"
            />
          </div>

          <div className="space-y-2">
            <Label className="text-xs uppercase tracking-wide text-gray-400">How was it paid? (self-reported)</Label>
            <div className="flex flex-wrap gap-2">
              {(Object.keys(TRADE_METHODS) as TradeMethod[]).map((m) => (
                <button
                  key={m}
                  type="button"
                  onClick={() => setMethod(m)}
                  className={cn(
                    'rounded-full border px-3 py-1.5 text-xs font-bold transition-colors',
                    method === m
                      ? 'border-[#ccff00] bg-[#ccff00]/15 text-[#ccff00]'
                      : 'border-white/15 text-gray-400 hover:border-white/30',
                  )}
                >
                  {TRADE_METHODS[m]}
                </button>
              ))}
            </div>
          </div>

          <div className="space-y-2">
            <Label htmlFor="amount" className="text-xs uppercase tracking-wide text-gray-400">
              Amount in sats (optional)
            </Label>
            <Input
              id="amount"
              value={amount}
              onChange={(e) => setAmount(e.target.value)}
              inputMode="numeric"
              placeholder="e.g. 45000"
              className="h-11 border-gray-700 bg-gray-900 text-white"
            />
          </div>

          <div className="flex gap-2 pt-1">
            <Button variant="outline" onClick={() => onOpenChange(false)} className="flex-1 border-white/15">
              Cancel
            </Button>
            <Button
              onClick={submit}
              disabled={busy || !buyerPubkey}
              className="flex-1 gap-2 bg-[#ccff00] font-bold text-black hover:bg-[#ccff00]/90"
            >
              {busy ? <Loader2 className="h-4 w-4 animate-spin" /> : <Check className="h-4 w-4" />}
              Mark sold
            </Button>
          </div>
        </div>
      </DialogContent>
    </Dialog>
  );
}