-- ============================================================
-- 勘察派单重构：客户设备树形化 + 勘察明细关联设备
-- 1) customer_equipment 增加 parent_id（自引用，树形层级：配电间→配电箱/井/柜，支持多级）
-- 2) customer_equipment.equip_type 增加「配电柜」选项（注释同步）
-- 3) survey_detail 增加 equip_id（关联 customer_equipment，明细照片/备注挂到设备节点）
-- 幂等：仅新增缺失的列/索引，重复执行结果一致
-- ============================================================

-- 1. customer_equipment.parent_id
ALTER TABLE customer_equipment
    ADD COLUMN IF NOT EXISTS parent_id BIGINT REFERENCES customer_equipment(id);
COMMENT ON COLUMN customer_equipment.parent_id IS '父设备ID（自引用，→ customer_equipment，空为根设备）';
CREATE INDEX IF NOT EXISTS idx_equip_parent ON customer_equipment (parent_id);

-- 2. 设备类型注释补充「配电柜」
COMMENT ON COLUMN customer_equipment.equip_type IS '设备类型：配电间/配电井/配电箱/配电柜';

-- 3. survey_detail.equip_id
ALTER TABLE survey_detail
    ADD COLUMN IF NOT EXISTS equip_id BIGINT REFERENCES customer_equipment(id);
COMMENT ON COLUMN survey_detail.equip_id IS '客户设备ID（→ customer_equipment，勘察明细挂接到设备节点）';
CREATE INDEX IF NOT EXISTS idx_survey_detail_equip ON survey_detail (equip_id);