-- Apply before enabling IM_PUSH_CALLBACK_URL and IM_PUSH_CALLBACK_SECRET.
CREATE TABLE IF NOT EXISTS `im_private_message_push_event` (
    `id` bigint NOT NULL AUTO_INCREMENT,
    `message_id` bigint NOT NULL COMMENT 'IM private message id',
    `payload` text NOT NULL COMMENT 'Signed callback JSON snapshot',
    `status` tinyint NOT NULL DEFAULT 0 COMMENT '0 pending, 1 accepted, 2 expired',
    `attempt_count` int NOT NULL DEFAULT 0,
    `next_retry_time` datetime(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
    `last_error` varchar(200) DEFAULT NULL,
    `create_time` datetime(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
    `update_time` datetime(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) ON UPDATE CURRENT_TIMESTAMP(3),
    PRIMARY KEY (`id`),
    UNIQUE KEY `uk_private_message_push_message` (`message_id`),
    KEY `idx_private_message_push_due` (`status`, `next_retry_time`, `id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='Durable private-message push delivery';