CREATE TABLE IF NOT EXISTS users (
 id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
 name VARCHAR(140) NOT NULL, email VARCHAR(190) NOT NULL UNIQUE,
 password_hash VARCHAR(255) NOT NULL, role VARCHAR(40) NOT NULL DEFAULT 'Satın Alma',
 active TINYINT(1) NOT NULL DEFAULT 1, created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
 updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
CREATE TABLE IF NOT EXISTS app_state (
 id TINYINT UNSIGNED NOT NULL PRIMARY KEY,
 payload LONGTEXT NOT NULL, revision BIGINT UNSIGNED NOT NULL DEFAULT 0,
 updated_by BIGINT UNSIGNED NULL, updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
 CONSTRAINT fk_state_user FOREIGN KEY(updated_by) REFERENCES users(id) ON DELETE SET NULL,
 CONSTRAINT chk_json CHECK(JSON_VALID(payload))
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
CREATE TABLE IF NOT EXISTS audit_logs (
 id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
 user_id BIGINT UNSIGNED NULL, action VARCHAR(120) NOT NULL,
 target VARCHAR(190) NOT NULL DEFAULT '', detail TEXT,
 ip_address VARCHAR(45) NULL, created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
 INDEX ix_audit_date(created_at), INDEX ix_audit_user(user_id),
 CONSTRAINT fk_audit_user FOREIGN KEY(user_id) REFERENCES users(id) ON DELETE SET NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;