'use client';

import React, { useState, useEffect } from 'react';
import { motion, AnimatePresence } from 'framer-motion';
import { X, QrCode, Keyboard, Loader2, CheckCircle2, Copy, RefreshCw, Link2 } from 'lucide-react';
import QRCode from 'react-qr-code';
import { generateBuddyCode, redeemBuddyCode, revokeBuddyCode } from '@/services/buddy-link';
import { useI18n } from '@/i18n/I18nContext';

interface BuddyHandshakeProps {
    isOpen: boolean;
    onClose: () => void;
    onSuccess?: () => void;
}

type Tab = 'show' | 'enter';

export default function BuddyHandshake({ isOpen, onClose, onSuccess }: BuddyHandshakeProps) {
    const { t } = useI18n();
    const [activeTab, setActiveTab] = useState<Tab>('show');

    // Show Code Tab State
    const [code, setCode] = useState<string | null>(null);
    const [isGenerating, setIsGenerating] = useState(false);
    const [copied, setCopied] = useState(false);

    // Enter Code Tab State
    const [inputCode, setInputCode] = useState('');
    const [isRedeeming, setIsRedeeming] = useState(false);
    const [redeemError, setRedeemError] = useState<string | null>(null);
    const [redeemSuccess, setRedeemSuccess] = useState<string | null>(null);

    // Generate code when showing "Show Code" tab
    useEffect(() => {
        if (isOpen && activeTab === 'show' && !code) {
            handleGenerateCode();
        }
    }, [isOpen, activeTab]);

    // Reset state when closing
    useEffect(() => {
        if (!isOpen) {
            setCode(null);
            setInputCode('');
            setRedeemError(null);
            setRedeemSuccess(null);
            setCopied(false);
        }
    }, [isOpen]);

    const handleGenerateCode = async () => {
        setIsGenerating(true);
        const result = await generateBuddyCode();
        if (result.success && result.code) {
            setCode(result.code);
        }
        setIsGenerating(false);
    };

    const handleRefreshCode = async () => {
        await revokeBuddyCode();
        setCode(null);
        handleGenerateCode();
    };

    const handleCopyCode = () => {
        if (code) {
            navigator.clipboard.writeText(code);
            setCopied(true);
            setTimeout(() => setCopied(false), 2000);
        }
    };

    const handleRedeemCode = async () => {
        if (!inputCode.trim()) return;

        setIsRedeeming(true);
        setRedeemError(null);
        setRedeemSuccess(null);

        const result = await redeemBuddyCode(inputCode);

        if (result.success) {
            setRedeemSuccess(`Verbunden mit ${result.buddyName}!`);
            setTimeout(() => {
                onSuccess?.();
                onClose();
            }, 1500);
        } else {
            setRedeemError(result.error || 'Unbekannter Fehler');
        }

        setIsRedeeming(false);
    };

    const formatCodeForDisplay = (code: string) => {
        // Format as XXX-XXX for better readability
        return `${code.slice(0, 3)}-${code.slice(3)}`;
    };

    if (!isOpen) return null;

    return (
        <AnimatePresence>
            <motion.div
                initial={{ opacity: 0 }}
                animate={{ opacity: 1 }}
                exit={{ opacity: 0 }}
                className="fixed inset-0 bg-black/80 backdrop-blur-xs z-50 flex items-center justify-center p-4"
                onClick={onClose}
            >
                <motion.div
                    initial={{ opacity: 0, scale: 0.95, y: 20 }}
                    animate={{ opacity: 1, scale: 1, y: 0 }}
                    exit={{ opacity: 0, scale: 0.95, y: 20 }}
                    className="w-full max-w-md bg-zinc-900 rounded-3xl border border-zinc-800 shadow-2xl overflow-hidden"
                    onClick={(e) => e.stopPropagation()}
                >
                    {/* Header */}
                    <div className="flex items-center justify-between p-5 border-b border-zinc-800">
                        <div className="flex items-center gap-3">
                            <div className="w-10 h-10 rounded-xl bg-orange-600/20 flex items-center justify-center">
                                <Link2 size={20} className="text-orange-500" />
                            </div>
                            <div>
                                <h2 className="text-lg font-bold text-white">Account verbinden</h2>
                                <p className="text-xs text-zinc-500">Buddy-Handshake</p>
                            </div>
                        </div>
                        <button
                            onClick={onClose}
                            className="p-2 hover:bg-zinc-800 rounded-xl transition-colors text-zinc-500 hover:text-white"
                        >
                            <X size={20} />
                        </button>
                    </div>

                    {/* Tabs */}
                    <div className="flex border-b border-zinc-800">
                        <button
                            onClick={() => setActiveTab('show')}
                            className={`flex-1 py-3.5 text-xs font-bold uppercase tracking-widest transition-all flex items-center justify-center gap-2 ${activeTab === 'show'
                                    ? 'text-orange-500 border-b-2 border-orange-500 bg-orange-500/5'
                                    : 'text-zinc-500 hover:text-zinc-300'
                                }`}
                        >
                            <QrCode size={14} />
                            Mein Code
                        </button>
                        <button
                            onClick={() => setActiveTab('enter')}
                            className={`flex-1 py-3.5 text-xs font-bold uppercase tracking-widest transition-all flex items-center justify-center gap-2 ${activeTab === 'enter'
                                    ? 'text-orange-500 border-b-2 border-orange-500 bg-orange-500/5'
                                    : 'text-zinc-500 hover:text-zinc-300'
                                }`}
                        >
                            <Keyboard size={14} />
                            Code eingeben
                        </button>
                    </div>

                    {/* Content */}
                    <div className="p-6">
                        {activeTab === 'show' ? (
                            <div className="flex flex-col items-center gap-6">
                                {isGenerating ? (
                                    <div className="py-12 flex flex-col items-center gap-4">
                                        <Loader2 size={32} className="animate-spin text-orange-500" />
                                        <p className="text-sm text-zinc-500">Generiere Code...</p>
                                    </div>
                                ) : code ? (
                                    <>
                                        {/* QR Code */}
                                        <div className="bg-white p-4 rounded-2xl">
                                            <QRCode
                                                value={`dramlog://buddy/${code}`}
                                                size={180}
                                                level="M"
                                            />
                                        </div>

                                        {/* Text Code */}
                                        <div className="flex flex-col items-center gap-2">
                                            <p className="text-xs text-zinc-500 uppercase tracking-widest">Oder Code teilen:</p>
                                            <div className="flex items-center gap-2">
                                                <span className="text-3xl font-black tracking-[0.3em] text-white font-mono">
                                                    {formatCodeForDisplay(code)}
                                                </span>
                                                <button
                                                    onClick={handleCopyCode}
                                                    className={`p-2 rounded-lg transition-all ${copied
                                                            ? 'bg-green-500/20 text-green-500'
                                                            : 'bg-zinc-800 hover:bg-zinc-700 text-zinc-400'
                                                        }`}
                                                >
                                                    {copied ? <CheckCircle2 size={18} /> : <Copy size={18} />}
                                                </button>
                                            </div>
                                        </div>

                                        {/* Timer/Refresh */}
                                        <div className="flex items-center gap-4 text-xs text-zinc-500">
                                            <span>Gültig für 15 Minuten</span>
                                            <button
                                                onClick={handleRefreshCode}
                                                className="flex items-center gap-1.5 text-orange-500 hover:text-orange-400"
                                            >
                                                <RefreshCw size={12} />
                                                Neuer Code
                                            </button>
                                        </div>
                                    </>
                                ) : (
                                    <div className="py-12 text-center text-zinc-500">
                                        <p>Fehler beim Generieren</p>
                                        <button
                                            onClick={handleGenerateCode}
                                            className="mt-4 text-orange-500 hover:underline"
                                        >
                                            Erneut versuchen
                                        </button>
                                    </div>
                                )}
                            </div>
                        ) : (
                            <div className="flex flex-col gap-6">
                                <p className="text-sm text-zinc-400 text-center">
                                    Gib den 6-stelligen Code deines Buddies ein:
                                </p>

                                {/* Code Input */}
                                <input
                                    type="text"
                                    value={inputCode}
                                    onChange={(e) => {
                                        const val = e.target.value.toUpperCase().replace(/[^A-Z0-9]/g, '');
                                        if (val.length <= 6) {
                                            setInputCode(val);
                                            setRedeemError(null);
                                        }
                                    }}
                                    placeholder="XXXXXX"
                                    className="w-full text-center text-3xl font-black tracking-[0.4em] bg-zinc-950 border-2 border-zinc-800 rounded-2xl py-4 text-white placeholder:text-zinc-700 focus:outline-hidden focus:border-orange-500 transition-colors font-mono"
                                    maxLength={6}
                                    autoFocus
                                />

                                {/* Error Message */}
                                {redeemError && (
                                    <motion.p
                                        initial={{ opacity: 0, y: -10 }}
                                        animate={{ opacity: 1, y: 0 }}
                                        className="text-sm text-red-500 text-center bg-red-500/10 py-2 px-4 rounded-xl"
                                    >
                                        {redeemError}
                                    </motion.p>
                                )}

                                {/* Success Message */}
                                {redeemSuccess && (
                                    <motion.div
                                        initial={{ opacity: 0, scale: 0.9 }}
                                        animate={{ opacity: 1, scale: 1 }}
                                        className="flex items-center justify-center gap-2 text-green-500 bg-green-500/10 py-3 px-4 rounded-xl"
                                    >
                                        <CheckCircle2 size={20} />
                                        <span className="font-bold">{redeemSuccess}</span>
                                    </motion.div>
                                )}

                                {/* Submit Button */}
                                <button
                                    onClick={handleRedeemCode}
                                    disabled={inputCode.length !== 6 || isRedeeming || !!redeemSuccess}
                                    className="w-full py-4 bg-orange-600 hover:bg-orange-700 disabled:bg-zinc-800 disabled:text-zinc-600 text-white font-bold rounded-2xl transition-all flex items-center justify-center gap-2"
                                >
                                    {isRedeeming ? (
                                        <>
                                            <Loader2 size={18} className="animate-spin" />
                                            Verbinde...
                                        </>
                                    ) : (
                                        <>
                                            <Link2 size={18} />
                                            Verbinden
                                        </>
                                    )}
                                </button>
                            </div>
                        )}
                    </div>
                </motion.div>
            </motion.div>
        </AnimatePresence>
    );
}
