新功能(#74): 新增促销系统模型层

Co-authored-by: multica-agent <github@multica.ai>

initialize/migrate/database/02154_promo_system.down.sql

@@ -0,0 +1,7 @@
+ALTER TABLE `order`
+  DROP COLUMN IF EXISTS `promo_discount`,
+  DROP COLUMN IF EXISTS `promo_rule_id`;
+
+DROP TABLE IF EXISTS `promo_usage`;
+DROP TABLE IF EXISTS `subscribe_promo`;
+DROP TABLE IF EXISTS `promo_rule`;

initialize/migrate/database/02154_promo_system.up.sql

@@ -0,0 +1,52 @@
+CREATE TABLE IF NOT EXISTS `promo_rule` (
+  `id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
+  `name` VARCHAR(100) NOT NULL DEFAULT '' COMMENT '规则名称，如"新客7天优惠"',
+  `type` VARCHAR(32) NOT NULL DEFAULT '' COMMENT '规则类型：new_user / inactive_user / campaign',
+  `params` JSON NOT NULL COMMENT '类型专属参数',
+  `priority` INT NOT NULL DEFAULT 0 COMMENT '优先级，数值越大越优先匹配',
+  `enabled` TINYINT(1) NOT NULL DEFAULT 1 COMMENT '是否启用',
+  `start_time` DATETIME DEFAULT NULL COMMENT '生效开始时间，NULL=立即生效',
+  `end_time` DATETIME DEFAULT NULL COMMENT '生效结束时间，NULL=永不过期',
+  `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  `updated_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+  `deleted_at` DATETIME DEFAULT NULL COMMENT '软删除时间',
+  PRIMARY KEY (`id`),
+  KEY `idx_enabled_priority` (`enabled`, `priority` DESC)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='促销规则表';
+
+CREATE TABLE IF NOT EXISTS `subscribe_promo` (
+  `id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
+  `subscribe_id` BIGINT UNSIGNED NOT NULL COMMENT '套餐规格 ID',
+  `promo_rule_id` BIGINT UNSIGNED NOT NULL COMMENT '促销规则 ID',
+  `promo_price` BIGINT NOT NULL DEFAULT 0 COMMENT '该规格在此规则下的优惠价（分）',
+  `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  `updated_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+  PRIMARY KEY (`id`),
+  UNIQUE KEY `uk_subscribe_rule` (`subscribe_id`, `promo_rule_id`),
+  KEY `idx_promo_rule_id` (`promo_rule_id`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='规格促销价表';
+
+CREATE TABLE IF NOT EXISTS `promo_usage` (
+  `id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
+  `user_id` BIGINT UNSIGNED NOT NULL COMMENT '用户 ID',
+  `promo_rule_id` BIGINT UNSIGNED NOT NULL COMMENT '使用的规则 ID',
+  `subscribe_id` BIGINT UNSIGNED NOT NULL COMMENT '购买的规格 ID',
+  `order_no` VARCHAR(255) NOT NULL DEFAULT '' COMMENT '关联订单号',
+  `promo_price` BIGINT NOT NULL DEFAULT 0 COMMENT '使用时的促销单价（分）',
+  `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  PRIMARY KEY (`id`),
+  KEY `idx_user_rule` (`user_id`, `promo_rule_id`),
+  KEY `idx_order_no` (`order_no`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='促销使用记录表';
+
+SET @promo_rule_id_exists = (SELECT COUNT(*) FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'order' AND COLUMN_NAME = 'promo_rule_id');
+SET @promo_rule_id_sql = IF(@promo_rule_id_exists = 0, 'ALTER TABLE `order` ADD COLUMN `promo_rule_id` BIGINT UNSIGNED NOT NULL DEFAULT 0 COMMENT ''促销规则ID, 0=未使用促销'' AFTER `discount`', 'SELECT 1');
+PREPARE stmt FROM @promo_rule_id_sql;
+EXECUTE stmt;
+DEALLOCATE PREPARE stmt;
+
+SET @promo_discount_exists = (SELECT COUNT(*) FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'order' AND COLUMN_NAME = 'promo_discount');
+SET @promo_discount_sql = IF(@promo_discount_exists = 0, 'ALTER TABLE `order` ADD COLUMN `promo_discount` BIGINT NOT NULL DEFAULT 0 COMMENT ''促销优惠金额(分)'' AFTER `promo_rule_id`', 'SELECT 1');
+PREPARE stmt FROM @promo_discount_sql;
+EXECUTE stmt;
+DEALLOCATE PREPARE stmt;