修复(#85): 按数量匹配订阅促销价

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

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

@@ -18,15 +18,70 @@ CREATE TABLE IF NOT EXISTS `promo_rule` (
 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',
+  `quantity` BIGINT NOT NULL DEFAULT 1 COMMENT '购买数量',
   `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`),
+  UNIQUE KEY `uk_subscribe_quantity_rule` (`subscribe_id`, `quantity`, `promo_rule_id`),
   KEY `idx_promo_rule_id` (`promo_rule_id`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='规格促销价表';
 
+SET @column_exists = (
+  SELECT COUNT(*)
+  FROM INFORMATION_SCHEMA.COLUMNS
+  WHERE TABLE_SCHEMA = DATABASE()
+    AND TABLE_NAME = 'subscribe_promo'
+    AND COLUMN_NAME = 'quantity'
+);
+
+SET @sql = IF(
+  @column_exists = 0,
+  'ALTER TABLE `subscribe_promo` ADD COLUMN `quantity` BIGINT NOT NULL DEFAULT 1 COMMENT ''购买数量'' AFTER `subscribe_id`',
+  'SELECT ''Column quantity already exists in subscribe_promo table'''
+);
+
+PREPARE stmt FROM @sql;
+EXECUTE stmt;
+DEALLOCATE PREPARE stmt;
+
+SET @index_exists = (
+  SELECT COUNT(*)
+  FROM INFORMATION_SCHEMA.STATISTICS
+  WHERE TABLE_SCHEMA = DATABASE()
+    AND TABLE_NAME = 'subscribe_promo'
+    AND INDEX_NAME = 'uk_subscribe_rule'
+);
+
+SET @sql = IF(
+  @index_exists = 1,
+  'ALTER TABLE `subscribe_promo` DROP INDEX `uk_subscribe_rule`',
+  'SELECT ''Index uk_subscribe_rule does not exist on subscribe_promo table'''
+);
+
+PREPARE stmt FROM @sql;
+EXECUTE stmt;
+DEALLOCATE PREPARE stmt;
+
+SET @index_exists = (
+  SELECT COUNT(*)
+  FROM INFORMATION_SCHEMA.STATISTICS
+  WHERE TABLE_SCHEMA = DATABASE()
+    AND TABLE_NAME = 'subscribe_promo'
+    AND INDEX_NAME = 'uk_subscribe_quantity_rule'
+);
+
+SET @sql = IF(
+  @index_exists = 0,
+  'ALTER TABLE `subscribe_promo` ADD UNIQUE KEY `uk_subscribe_quantity_rule` (`subscribe_id`, `quantity`, `promo_rule_id`)',
+  'SELECT ''Index uk_subscribe_quantity_rule already exists on subscribe_promo table'''
+);
+
+PREPARE stmt FROM @sql;
+EXECUTE stmt;
+DEALLOCATE PREPARE stmt;
+
 CREATE TABLE IF NOT EXISTS `promo_usage` (
   `id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
   `user_id` BIGINT UNSIGNED NOT NULL COMMENT '用户 ID',