CREATE TABLE IF NOT EXISTS notifications (
    id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
    user_id BIGINT UNSIGNED NOT NULL,
    type VARCHAR(80) NOT NULL,
    title VARCHAR(160) NOT NULL,
    body TEXT NULL,
    report_id BIGINT UNSIGNED NULL,
    read_at DATETIME NULL,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    CONSTRAINT notifications_user_fk FOREIGN KEY (user_id) REFERENCES users(id),
    CONSTRAINT notifications_report_fk FOREIGN KEY (report_id) REFERENCES reports(id),
    KEY notifications_user_read_created_idx (user_id, read_at, created_at),
    KEY notifications_report_idx (report_id)
);

CREATE TABLE IF NOT EXISTS moderation_flags (
    id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
    content_type VARCHAR(30) NOT NULL,
    report_id BIGINT UNSIGNED NOT NULL,
    message_id BIGINT UNSIGNED NULL,
    reason VARCHAR(120) NOT NULL,
    details TEXT NULL,
    status VARCHAR(30) NOT NULL DEFAULT 'OPEN',
    created_by_user_id BIGINT UNSIGNED NOT NULL,
    resolved_by_user_id BIGINT UNSIGNED NULL,
    resolution_note TEXT NULL,
    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    resolved_at DATETIME NULL,
    CONSTRAINT moderation_flags_report_fk FOREIGN KEY (report_id) REFERENCES reports(id),
    CONSTRAINT moderation_flags_message_fk FOREIGN KEY (message_id) REFERENCES messages(id),
    CONSTRAINT moderation_flags_created_by_fk FOREIGN KEY (created_by_user_id) REFERENCES users(id),
    CONSTRAINT moderation_flags_resolved_by_fk FOREIGN KEY (resolved_by_user_id) REFERENCES users(id),
    KEY moderation_flags_status_created_idx (status, created_at),
    KEY moderation_flags_report_idx (report_id),
    KEY moderation_flags_message_idx (message_id)
);

ALTER TABLE reward_events
    ADD UNIQUE KEY reward_events_report_reason_unique (report_id, reason);