CREATE TABLE IF NOT EXISTS users (
    id TEXT PRIMARY KEY,
    username TEXT UNIQUE,
    password_hash TEXT,
    display_name TEXT,
    bio TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

CREATE TABLE IF NOT EXISTS tweets (
    id TEXT PRIMARY KEY,
    user_id TEXT,
    content TEXT,
    quote_tweet_id TEXT,
    reply_to_id TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES users(id),
    FOREIGN KEY (quote_tweet_id) REFERENCES tweets(id),
    FOREIGN KEY (reply_to_id) REFERENCES tweets(id)
);

CREATE TABLE IF NOT EXISTS follows (
    follower_id TEXT,
    followed_id TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    PRIMARY KEY (follower_id, followed_id),
    FOREIGN KEY (follower_id) REFERENCES users(id),
    FOREIGN KEY (followed_id) REFERENCES users(id)
);

CREATE TABLE IF NOT EXISTS likes (
    user_id TEXT,
    tweet_id TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    PRIMARY KEY (user_id, tweet_id),
    FOREIGN KEY (user_id) REFERENCES users(id),
    FOREIGN KEY (tweet_id) REFERENCES tweets(id)
);

CREATE TABLE IF NOT EXISTS bookmarks (
    user_id TEXT,
    tweet_id TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    PRIMARY KEY (user_id, tweet_id),
    FOREIGN KEY (user_id) REFERENCES users(id),
    FOREIGN KEY (tweet_id) REFERENCES tweets(id)
);

CREATE TABLE IF NOT EXISTS retweets (
    user_id TEXT,
    tweet_id TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    PRIMARY KEY (user_id, tweet_id),
    FOREIGN KEY (user_id) REFERENCES users(id),
    FOREIGN KEY (tweet_id) REFERENCES tweets(id)
);

CREATE TABLE IF NOT EXISTS messages (
    id TEXT PRIMARY KEY,
    sender_id TEXT,
    receiver_id TEXT,
    content TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (sender_id) REFERENCES users(id),
    FOREIGN KEY (receiver_id) REFERENCES users(id)
);