-- Ledger platform schema
CREATE DATABASE IF NOT EXISTS igpromo CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
USE igpromo;

CREATE TABLE users (
    id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(50) NOT NULL UNIQUE,
    email VARCHAR(190) NOT NULL UNIQUE,
    password_hash VARCHAR(255) NOT NULL,
    display_name VARCHAR(100) NOT NULL,
    avatar_url VARCHAR(255) DEFAULT NULL,
    bio VARCHAR(280) DEFAULT NULL,
    coin_balance INT NOT NULL DEFAULT 0,
    ig_handle VARCHAR(50) DEFAULT NULL,
    is_verified TINYINT(1) NOT NULL DEFAULT 0,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
) ENGINE=InnoDB;

CREATE TABLE coin_transactions (
    id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    user_id INT UNSIGNED NOT NULL,
    amount INT NOT NULL, -- positive = credit, negative = debit
    reason VARCHAR(100) NOT NULL, -- signup_bonus, purchase, promotion_spend, referral, etc
    reference_id INT UNSIGNED DEFAULT NULL,
    balance_after INT NOT NULL,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
) ENGINE=InnoDB;

CREATE TABLE posts (
    id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    user_id INT UNSIGNED NOT NULL,
    image_url VARCHAR(255) NOT NULL,
    caption VARCHAR(500) DEFAULT NULL,
    like_count INT UNSIGNED NOT NULL DEFAULT 0,
    comment_count INT UNSIGNED NOT NULL DEFAULT 0,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
) ENGINE=InnoDB;

CREATE TABLE follows (
    follower_id INT UNSIGNED NOT NULL,
    following_id INT UNSIGNED NOT NULL,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    PRIMARY KEY (follower_id, following_id),
    FOREIGN KEY (follower_id) REFERENCES users(id) ON DELETE CASCADE,
    FOREIGN KEY (following_id) REFERENCES users(id) ON DELETE CASCADE
) ENGINE=InnoDB;

CREATE INDEX idx_users_search ON users (username, display_name);
CREATE INDEX idx_posts_user ON posts (user_id, created_at);