-- prc_price_set_detail: weight_min/weight_max + effective_date/expire_date
-- same types as bms_product_country
SET NAMES utf8mb4;
SET @db := DATABASE();

SET @has := (SELECT COUNT(*) FROM information_schema.COLUMNS WHERE TABLE_SCHEMA=@db AND TABLE_NAME='prc_price_set_detail' AND COLUMN_NAME='weight_min');
SET @sql := IF(@has=0, 'ALTER TABLE prc_price_set_detail ADD COLUMN weight_min DECIMAL(10,3) DEFAULT NULL COMMENT ''重量段最小值KG（含）'' AFTER weight_label', 'SELECT 1');
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @has := (SELECT COUNT(*) FROM information_schema.COLUMNS WHERE TABLE_SCHEMA=@db AND TABLE_NAME='prc_price_set_detail' AND COLUMN_NAME='weight_max');
SET @sql := IF(@has=0, 'ALTER TABLE prc_price_set_detail ADD COLUMN weight_max DECIMAL(10,3) DEFAULT NULL COMMENT ''重量段最大值KG（含）'' AFTER weight_min', 'SELECT 1');
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @has := (SELECT COUNT(*) FROM information_schema.COLUMNS WHERE TABLE_SCHEMA=@db AND TABLE_NAME='prc_price_set_detail' AND COLUMN_NAME='effective_date');
SET @sql := IF(@has=0, 'ALTER TABLE prc_price_set_detail ADD COLUMN effective_date DATE DEFAULT NULL COMMENT ''生效日期'' AFTER pr_id', 'SELECT 1');
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @has := (SELECT COUNT(*) FROM information_schema.COLUMNS WHERE TABLE_SCHEMA=@db AND TABLE_NAME='prc_price_set_detail' AND COLUMN_NAME='expire_date');
SET @sql := IF(@has=0, 'ALTER TABLE prc_price_set_detail ADD COLUMN expire_date DATE DEFAULT NULL COMMENT ''失效日期（空=长期）'' AFTER effective_date', 'SELECT 1');
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @has := (SELECT COUNT(*) FROM information_schema.STATISTICS WHERE TABLE_SCHEMA=@db AND TABLE_NAME='prc_price_set_detail' AND INDEX_NAME='idx_psd_weight_match');
SET @sql := IF(@has=0, 'ALTER TABLE prc_price_set_detail ADD INDEX idx_psd_weight_match (price_set_id, product_code, country_code, weight_min, weight_max)', 'SELECT 1');
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @has := (SELECT COUNT(*) FROM information_schema.STATISTICS WHERE TABLE_SCHEMA=@db AND TABLE_NAME='prc_price_set_detail' AND INDEX_NAME='idx_psd_eff');
SET @sql := IF(@has=0, 'ALTER TABLE prc_price_set_detail ADD INDEX idx_psd_eff (price_set_id, effective_date, expire_date)', 'SELECT 1');
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

-- 回填: 从 bms_product_country 带入重量段与有效期
UPDATE prc_price_set_detail d
INNER JOIN bms_product_country c ON c.detail_id = d.product_country_id
SET
  d.weight_min = IFNULL(d.weight_min, c.weight_min),
  d.weight_max = IFNULL(d.weight_max, c.weight_max),
  d.effective_date = IFNULL(d.effective_date, c.effective_date),
  d.expire_date = IFNULL(d.expire_date, c.expire_date)
WHERE d.product_country_id IS NOT NULL;