NFT Marketplace Builder

-- Users table
CREATE TABLE users (
    id UUID PRIMARY KEY,
    wallet_address VARCHAR(42) UNIQUE NOT NULL,
    username VARCHAR(50) UNIQUE,
    email VARCHAR(255),
    profile_image_url TEXT,
    verification_level INTEGER DEFAULT 0,
    created_at TIMESTAMP DEFAULT NOW()
);

-- NFT Collections
CREATE TABLE collections (
    id UUID PRIMARY KEY,
    contract_address VARCHAR(42) NOT NULL,
    creator_id UUID REFERENCES users(id),
    name VARCHAR(255) NOT NULL,
    description TEXT,
    image_url TEXT,
    royalty_percentage DECIMAL(5,2),
    total_supply INTEGER,
    created_at TIMESTAMP DEFAULT NOW()
);

-- NFT Items
CREATE TABLE nft_items (
    id UUID PRIMARY KEY,
    collection_id UUID REFERENCES collections(id),
    token_id INTEGER NOT NULL,
    name VARCHAR(255) NOT NULL,
    description TEXT,
    image_url TEXT NOT NULL,
    metadata_url TEXT,
    current_owner_id UUID REFERENCES users(id),
    creator_id UUID REFERENCES users(id),
    is_minted BOOLEAN DEFAULT FALSE,
    created_at TIMESTAMP DEFAULT NOW()
);

-- Marketplace Listings
CREATE TABLE listings (
    id UUID PRIMARY KEY,
    nft_item_id UUID REFERENCES nft_items(id),
    seller_id UUID REFERENCES users(id),
    listing_type VARCHAR(20) NOT NULL, -- 'fixed', 'auction', 'offer'
    price DECIMAL(20,8) NOT NULL,
    currency VARCHAR(10) DEFAULT 'ETH',
    start_time TIMESTAMP DEFAULT NOW(),
    end_time TIMESTAMP,
    is_active BOOLEAN DEFAULT TRUE,
    created_at TIMESTAMP DEFAULT NOW()
);