// Configuration
const RARIBLE_API_KEY = 'd01c6b48-8f7a-4f58-8a1e-5c5a5d9c5b9a'; // New test API key
const RARIBLE_API_BASE = 'https://api.rarible.org/v0.1';
const CONTRACT_ADDRESS = 'ETHEREUM:0x60f80121c31a0d46b5279700f9df786054aa5ee5'; // New test contract
// State
let state = {
    walletAddress: null,
    nfts: [],
    filteredNFTs: [],
    isLoading: false,
    currentFilter: 'all'
};

// DOM Elements
const elements = {
    connectWalletBtn: document.getElementById('connectWallet'),
    disconnectWalletBtn: document.getElementById('disconnectWallet'),
    walletAddressEl: document.getElementById('walletAddress'),
    walletInfoEl: document.getElementById('walletInfo'),
    nftContainer: document.getElementById('nftContainer'),
    searchInput: document.getElementById('searchInput'),
    filterButtons: document.querySelectorAll('.filter-btn'),
    refreshBtn: document.getElementById('refreshNFTs'),
    statusMessage: document.getElementById('statusMessage')
};

// Initialize
document.addEventListener('DOMContentLoaded', async () => {
    await checkWalletConnection();
    setupEventListeners();
});

// Check if wallet is already connected
async function checkWalletConnection() {
    if (typeof window.ethereum === 'undefined') {
        window.demoMode = true;
        showStatus('No wallet detected - using demo mode', 'info');
        return;
    }

    try {
        const accounts = await window.ethereum.request({ method: 'eth_accounts' });
        if (accounts.length > 0) {
            state.walletAddress = accounts[0];
            updateWalletDisplay();
            showStatus('Wallet connected! Click Refresh to load NFTs.', 'success');
        } else {
            window.demoMode = true;
            showStatus('Connect wallet or use demo mode', 'info');
        }
    } catch (error) {
        console.error('Error checking wallet:', error);
        window.demoMode = true;
        showStatus('Using demo mode', 'info');
    }
}
// Connect Wallet
elements.connectWalletBtn.addEventListener('click', async () => {
    if (typeof window.ethereum === 'undefined') {
        window.demoMode = true;
        showStatus('No wallet detected - using demo mode', 'info');
        fetchNFTs();
        return;
    }

    try {
        elements.connectWalletBtn.disabled = true;
        elements.connectWalletBtn.textContent = 'Connecting...';
        showStatus('Connecting to wallet...', 'info');
        
        const accounts = await window.ethereum.request({
            method: 'eth_requestAccounts'
        });
        
        if (accounts.length > 0) {
            state.walletAddress = accounts[0];
            window.demoMode = false;
            updateWalletDisplay();
            showStatus('Wallet connected! Click Refresh to load NFTs.', 'success');
            window.ethereum.on('accountsChanged', handleAccountsChanged);
        } else {
            window.demoMode = true;
            showStatus('Using demo mode', 'info');
        }
        
    } catch (error) {
        console.error('Error connecting wallet:', error);
        window.demoMode = true;
        showStatus('Using demo mode', 'info');
        fetchNFTs();
    } finally {
        elements.connectWalletBtn.disabled = false;
        elements.connectWalletBtn.textContent = 'Connect Wallet';
    }
});
// Disconnect Wallet
elements.disconnectWalletBtn.addEventListener('click', () => {
    disconnectWallet();
});

// Handle account changes
function handleAccountsChanged(accounts) {
    if (accounts.length === 0) {
        disconnectWallet();
        showStatus('Wallet disconnected', 'info');
    } else {
        state.walletAddress = accounts[0];
        updateWalletDisplay();
        showStatus('Wallet account changed', 'info');
        // Optionally reload NFTs
        fetchNFTs();
    }
}

// Disconnect wallet function
function disconnectWallet() {
    state.walletAddress = null;
    state.nfts = [];
    state.filteredNFTs = [];
    window.demoMode = true;
    
    if (window.ethereum?.removeListener) {
        window.ethereum.removeListener('accountsChanged', handleAccountsChanged);
    }
    
    elements.walletInfoEl.style.display = 'none';
    elements.connectWalletBtn.style.display = 'block';
    elements.connectWalletBtn.disabled = false;
    
    fetchNFTs(); // Will fall back to demo mode
    showStatus('Wallet disconnected - using demo mode', 'info');
}
// Update wallet display
function updateWalletDisplay() {
    if (state.walletAddress) {
        const shortAddress = `${state.walletAddress.substring(0, 6)}...${state.walletAddress.substring(38)}`;
        elements.walletAddressEl.textContent = shortAddress;
        
        elements.walletInfoEl.style.display = 'flex';
        elements.connectWalletBtn.style.display = 'none';
    }
}

// Show status message
function showStatus(message, type = 'info') {
    elements.statusMessage.textContent = message;
    elements.statusMessage.className = `status-message ${type}`;
    elements.statusMessage.style.display = 'block';
    
    // Auto-hide after 5 seconds
    setTimeout(() => {
        elements.statusMessage.style.display = 'none';
    }, 5000);
}

// Fetch NFTs from Rarible API
async function fetchNFTs() {
    if (state.isLoading) {
        showStatus('Already loading NFTs...', 'info');
        return;
    }
    
    if (!state.walletAddress && !window.demoMode) {
        showStatus('Please connect your wallet first', 'error');
        return;
    }
    
    try {
        state.isLoading = true;
        elements.refreshBtn.disabled = true;
        elements.refreshBtn.textContent = 'Loading...';
        showStatus('Loading NFTs...', 'info');
        
        renderLoadingState();
        
        if (window.demoMode) {
            // Use demo data
            const demoNFTs = [
                {
                    id: 'demo1',
                    meta: {
                        name: 'Cosmic Explorer #1',
                        description: 'A demo NFT for testing purposes',
                        image: 'http://static.photos/abstract/640x360/1'
                    },
                    sellOrders: [{
                        id: 'order1',
                        take: {
                            value: '1000000000000000000', // 1 ETH
                            type: { '@type': 'ETH', decimals: 18 }
                        }
                    }]
                },
                {
                    id: 'demo2',
                    meta: {
                        name: 'Stellar Artwork',
                        description: 'Another demo NFT for testing',
                        image: 'http://static.photos/abstract/640x360/2'
                    },
                    sellOrders: []
                },
                {
                    id: 'demo3',
                    meta: {
                        name: 'Quantum Pixel',
                        description: 'Digital art piece',
                        image: 'http://static.photos/abstract/640x360/3'
                    },
                    sellOrders: [{
                        id: 'order3',
                        take: {
                            value: '250000000000000000', // 0.25 ETH
                            type: { '@type': 'ETH', decimals: 18 }
                        }
                    }]
                }
            ];
            
            state.nfts = demoNFTs;
            state.filteredNFTs = [...demoNFTs];
            applyFilter(state.currentFilter);
            showStatus('Demo mode: Loaded 3 test NFTs', 'success');
            return;
        }
        
        // Real API fetch
        const encodedWallet = encodeURIComponent(`ETHEREUM:${state.walletAddress}`);
        const apiUrl = `${RARIBLE_API_BASE}/items/byOwner?owner=${encodedWallet}&size=50`;
        
        const response = await fetch(apiUrl, {
            headers: {
                'X-API-KEY': RARIBLE_API_KEY,
                'Accept': 'application/json'
            }
        });
        
        if (!response.ok) {
            throw new Error(`API error: ${response.status}`);
        }
        
        const data = await response.json();
        state.nfts = data.items || [];
        state.filteredNFTs = [...state.nfts];
        
        if (state.nfts.length === 0) {
            renderEmptyState('No NFTs found in your wallet');
            showStatus('No NFTs found in your wallet', 'info');
            return;
        }
        
        applyFilter(state.currentFilter);
        showStatus(`Loaded ${state.nfts.length} NFTs`, 'success');
        
    } catch (error) {
        console.error('Error:', error);
        window.demoMode = true;
        fetchNFTs(); // Fallback to demo mode
    } finally {
        state.isLoading = false;
        elements.refreshBtn.disabled = false;
        elements.refreshBtn.textContent = '🔄 Refresh NFTs';
    }
}
// Enrich NFT with order data
async function enrichNFTWithOrderData(nft) {
    try {
        const itemId = encodeURIComponent(nft.id);
        
        // Get sell orders for this NFT
        const ordersResponse = await fetch(
            `${RARIBLE_API_BASE}/orders/items/${itemId}/sell`,
            {
                headers: {
                    'X-API-KEY': RARIBLE_API_KEY,
                    'Accept': 'application/json'
                }
            }
        );
        
        if (ordersResponse.ok) {
            const ordersData = await ordersResponse.json();
            nft.sellOrders = (ordersData.orders || []).filter(order =>
                order.status === 'ACTIVE' &&
                order.makeStock > 0 // Ensure there's available stock
            );
            
            // Get best price (lowest)
            if (nft.sellOrders.length > 0) {
                nft.bestOrder = nft.sellOrders.reduce((best, current) => {
                    const bestPrice = best ? parseFloat(best.take.value) : Infinity;
                    const currentPrice = current ? parseFloat(current.take.value) : Infinity;
                    return currentPrice < bestPrice ? current : best;
                });
            }
        } else {
            nft.sellOrders = [];
            nft.bestOrder = null;
        }
        
    } catch (error) {
        console.error('Error enriching NFT:', nft.id, error);
        nft.sellOrders = [];
        nft.bestOrder = null;
    }
}

// Render NFTs without flickering
function renderNFTs() {
    if (!elements.nftContainer) return;
    
    if (state.filteredNFTs.length === 0) {
        renderEmptyState('No NFTs match your filter');
        return;
    }
    
    // Clear and render in one operation to prevent flickering
    const fragment = document.createDocumentFragment();
    
    state.filteredNFTs.forEach((nft, index) => {
        const card = createNFTCard(nft, index);
        fragment.appendChild(card);
    });
    
    elements.nftContainer.innerHTML = '';
    elements.nftContainer.appendChild(fragment);
}

// Create NFT Card Element
function createNFTCard(nft, index) {
    const card = document.createElement('div');
    card.className = 'nft-card';
    card.style.animationDelay = `${index * 0.05}s`;
    
    // Check if NFT is for sale
    const isForSale = nft.sellOrders && nft.sellOrders.length > 0 && nft.bestOrder;
    let price = 'Not Listed';
    let priceValue = 0;
    
    if (isForSale && nft.bestOrder.take) {
        const decimals = nft.bestOrder.take.type?.decimals || 18;
        priceValue = parseFloat(nft.bestOrder.take.value) / Math.pow(10, decimals);
        const currency = nft.bestOrder.take.type?.['@type'] === 'ETH' ? 'ETH' :
                       nft.bestOrder.take.assetType?.assetClass || 'ETH';
        price = `${priceValue.toFixed(4)} ${currency}`;
    }
    
    // Get image URL
    let imageUrl = getImageUrl(nft);
    
    const nftName = nft.meta?.name || `NFT #${nft.tokenId || 'Unknown'}`;
    const description = nft.meta?.description || 'No description available';
    
    card.innerHTML = `
        <div class="nft-image-container">
            <img src="${imageUrl}" 
                 alt="${escapeHtml(nftName)}" 
                 class="nft-image" 
                 loading="lazy"
                 onerror="this.src='https://via.placeholder.com/400x400/14141f/a0a0b8?text=NFT'">
        </div>
        <div class="nft-info">
            <h3 class="nft-name" title="${escapeHtml(nftName)}">${escapeHtml(nftName)}</h3>
            <p class="nft-description">${escapeHtml(description)}</p>
            <div class="nft-price ${isForSale ? 'for-sale' : 'not-for-sale'}">${price}</div>
            <button class="buy-button" 
                    data-nft-id="${nft.id}"
                    data-order-id="${isForSale ? nft.bestOrder.id : ''}"
                    ${!isForSale ? 'disabled' : ''}>
                ${!isForSale ? 'Not Listed' : `Buy for ${price}`}
            </button>
        </div>
    `;
    
    // Add click event to buy button
    const buyButton = card.querySelector('.buy-button');
    if (buyButton && isForSale) {
        buyButton.addEventListener('click', () => handleBuy(nft.id, nft.bestOrder, priceValue));
    }
    
    return card;
}

// Get image URL from NFT metadata
function getImageUrl(nft) {
    let imageUrl = 'https://via.placeholder.com/400x400/14141f/a0a0b8?text=Loading...';
    
    if (nft.meta?.image) {
        if (typeof nft.meta.image === 'string') {
            imageUrl = nft.meta.image;
        } else if (nft.meta.image?.url) {
            imageUrl = nft.meta.image.url.ORIGINAL ||
                      nft.meta.image.url.BIG ||
                      nft.meta.image.url.PREVIEW ||
                      nft.meta.image.url;
        } else if (nft.meta.image?.PREVIEW) {
            imageUrl = nft.meta.image.PREVIEW;
        }
    }
    
    // Fallback to content array
    if (imageUrl.includes('placeholder') && nft.meta?.content && Array.isArray(nft.meta.content)) {
        const imageContent = nft.meta.content.find(item =>
            item['@type'] === 'IMAGE' || item.type === 'image'
        );
        if (imageContent?.url) {
            imageUrl = imageContent.url;
        }
    }
    
    // Convert IPFS URLs
    if (imageUrl.startsWith('ipfs://')) {
        imageUrl = imageUrl.replace('ipfs://', 'https://ipfs.io/ipfs/');
    }
    
    return imageUrl;
}

// Escape HTML to prevent XSS
function escapeHtml(text) {
    const div = document.createElement('div');
    div.textContent = text;
    return div.innerHTML;
}

// Handle Buy Function
async function handleBuy(nftId, order, price) {
    if (!window.ethereum || !state.walletAddress) {
        showStatus('Please connect wallet first', 'error');
        return;
    }
    
    try {
        const buyButton = document.querySelector(`[data-nft-id="${nftId}"]`);
        if (!buyButton) return;
        
        const originalText = buyButton.textContent;
        buyButton.disabled = true;
        buyButton.textContent = 'Processing...';
        
        showStatus('Starting purchase process...', 'info');
        
        // In production, you would integrate with Rarible SDK or Web3
        // For demo purposes:
        const confirmBuy = confirm(
            `DEMO MODE\n\n` +
            `This would purchase the NFT for ${price} ETH.\n\n` +
            `In production, this would:\n` +
            `1. Verify the order is still active\n` +
            `2. Request approval for payment token\n` +
            `3. Execute the purchase transaction\n` +
            `4. Transfer the NFT to your wallet\n\n` +
            `Continue with demo?`
        );
        
        if (confirmBuy) {
            showStatus('Demo purchase initiated! In production, this would trigger a blockchain transaction.', 'success');
            
            setTimeout(() => {
                buyButton.textContent = '✓ Demo Complete';
                buyButton.style.background = 'linear-gradient(135deg, #00ff88 0%, #00cc66 100%)';
            }, 1500);
        } else {
            buyButton.disabled = false;
            buyButton.textContent = originalText;
        }
        
    } catch (error) {
        console.error('Error in purchase process:', error);
        showStatus('Error in purchase process', 'error');
        
        const buyButton = document.querySelector(`[data-nft-id="${nftId}"]`);
        if (buyButton) {
            buyButton.disabled = false;
            buyButton.textContent = `Buy for ${price} ETH`;
        }
    }
}

// Apply filter
function applyFilter(filter) {
    state.currentFilter = filter;
    
    switch(filter) {
        case 'for-sale':
            state.filteredNFTs = state.nfts.filter(nft =>
                nft.sellOrders && nft.sellOrders.length > 0
            );
            break;
        case 'not-for-sale':
            state.filteredNFTs = state.nfts.filter(nft =>
                !nft.sellOrders || nft.sellOrders.length === 0
            );
            break;
        default:
            state.filteredNFTs = [...state.nfts];
    }
    
    renderNFTs();
    showStatus(`Showing ${state.filteredNFTs.length} NFTs`, 'info');
}

// Search NFTs
function searchNFTs(searchTerm) {
    const term = searchTerm.toLowerCase().trim();
    
    if (term === '') {
        state.filteredNFTs = [...state.nfts];
    } else {
        state.filteredNFTs = state.nfts.filter(nft => {
            const name = (nft.meta?.name || '').toLowerCase();
            const description = (nft.meta?.description || '').toLowerCase();
            const tokenId = (nft.tokenId || '').toString().toLowerCase();
            
            return name.includes(term) ||
                   description.includes(term) ||
                   tokenId.includes(term);
        });
    }
    
    applyFilter(state.currentFilter);
}

// Render states
function renderLoadingState() {
    elements.nftContainer.innerHTML = `
        <div class="loading">
            <div class="spinner"></div>
            <p>Loading your NFTs from the blockchain...</p>
        </div>
    `;
}

function renderEmptyState(message) {
    elements.nftContainer.innerHTML = `
        <div class="empty-state">
            <h3>No NFTs Found</h3>
            <p>${message}</p>
        </div>
    `;
}

function renderErrorState(errorMessage) {
    elements.nftContainer.innerHTML = `
        <div class="error-state">
            <h3>Error Loading NFTs</h3>
            <p>${errorMessage}</p>
            <p>Please check your connection and try again.</p>
        </div>
    `;
}

// Setup Event Listeners
function setupEventListeners() {
    // Refresh button
    elements.refreshBtn.addEventListener('click', fetchNFTs);
    
    // Search with debounce
    let searchTimeout;
    elements.searchInput.addEventListener('input', (e) => {
        clearTimeout(searchTimeout);
        searchTimeout = setTimeout(() => {
            searchNFTs(e.target.value);
        }, 300);
    });
    
    // Filter buttons
    elements.filterButtons.forEach(button => {
        button.addEventListener('click', () => {
            elements.filterButtons.forEach(btn => btn.classList.remove('active'));
            button.classList.add('active');
            
            const filter = button.dataset.filter;
            applyFilter(filter);
        });
    });
}

// Debug utilities
window.debug = {
    getState: () => state,
    getNFTs: () => state.nfts,
    getFilteredNFTs: () => state.filteredNFTs,
    reloadNFTs: fetchNFTs,
    getSellOrders: (index) => state.nfts[index]?.sellOrders || []
};