Preorder - Prelim DB changes

db/sql/1-tables.sql

@@ -1,7 +1,7 @@
 create type sos."delivery_type_enum"      as enum ('hand_shipped', 'easypost', 'hand_delivered');
 create type sos."transaction_state_enum"  as enum ('started', 'completed', 'cancelled', 'expired');
 create type sos."payment_type_enum"       as enum ('ks_reward', 'stripe', 'paypal', 'account_credit', 'admin_granted');
-create type sos."stockchange_type_enum"   as enum ('purchase', 'shipment', 'admin');
+create type sos."stockchange_type_enum"   as enum ('purchase', 'shipment', 'admin', 'preorder');
 create type sos."stock_change_dir_enum"   as enum ('added', 'subtracted');
 create type sos."email_link_type_enum"    as enum ('email_confirm', 'email_change', 'password_reset');
 
@@ -53,7 +53,14 @@ create table sos."item" (
   item_customs_description text not null,
   item_customs_origin_country text not null,
   item_weight_oz integer not null,
-  item_published  boolean not null default true
+  item_published  boolean not null default true,
+  item_preorder_availability_date timestamptz,
+  item_preorder_maximum integer check (item_preorder_maximum is null or item_preorder_maximum >= 0),
+
+  constraint item_cannot_have_preorder_date_without_max check (
+    ( item_preorder_availability_date is not null and item_preorder_maximum is not null )
+    or ( item_preorder_availability_date is null and item_preorder_maximum is null )
+  )
 );
 
 create table sos."cart_item" (
@@ -267,6 +274,16 @@ create table sos."item_stockchange_purchase" (
   stockchange_transaction_uuid   uuid                    references sos."transaction" (transaction_uuid)
 );
 
+create table sos."item_stockchange_preorder" (
+  stockchange_uuid        uuid                    primary key default uuid_generate_v4(),
+  stockchange_type        sos.stockchange_type_enum   check (stockchange_type = 'preorder'),
+  foreign key (stockchange_uuid, stockchange_type) references sos."item_stockchange" (stockchange_uuid, stockchange_type),
+
+  stockchange_transaction_uuid   uuid                 references sos."transaction" (transaction_uuid),
+  stockchange_preorder_estimated_fulfill_date  timestamptz not null,
+  stockchange_preorder_ready_to_ship  boolean         not null default false
+);
+
 create table sos."item_stockchange_shipment" (
   stockchange_uuid          uuid                    primary key default uuid_generate_v4(),
   stockchange_type          sos.stockchange_type_enum   check (stockchange_type = 'shipment'),

db/sql/2-views.sql

@@ -162,6 +162,7 @@ create or replace view sos.v_stockchange as
   from sos."item_stockchange"
     left join sos."item_stockchange_shipment" on item_stockchange.stockchange_uuid = item_stockchange_shipment.stockchange_uuid
     left join sos."item_stockchange_purchase" on item_stockchange.stockchange_uuid = item_stockchange_purchase.stockchange_uuid
+    left join sos."item_stockchange_preorder"    on item_stockchange.stockchange_uuid = item_stockchange_preorder.stockchange_uuid
     left join sos."item_stockchange_admin"    on item_stockchange.stockchange_uuid = item_stockchange_admin.stockchange_uuid;
 
 create or replace view sos.v_shipment as