-- Orders are written before calling WeChat. Keep them when a user or
-- organization is deleted so paid money cannot lose its audit trail.
create table if not exists public.payment_orders (
  id text primary key check (length(id) between 1 and 32 and id ~ '^[A-Za-z0-9_-]+$'),
  organization_id text not null references public.platform_organizations(id) on delete restrict,
  account_id text not null references public.platform_users(id) on delete restrict,
  request_key text not null check (length(request_key) between 1 and 64 and request_key ~ '^[A-Za-z0-9_-]+$'),
  mch_id text not null check (length(mch_id) between 1 and 64),
  app_id text not null check (length(app_id) between 1 and 64),
  amount_fen bigint not null check (amount_fen between 1 and 1000000),
  currency text not null check (currency = 'CNY'),
  status text not null default 'pending' check (status in ('pending', 'paid', 'closed')),
  code_url text,
  transaction_id text,
  created_at timestamptz not null default now(),
  updated_at timestamptz not null default now(),
  expires_at timestamptz not null,
  paid_at timestamptz,
  constraint payment_orders_paid_fields_check check (
    (status = 'paid' and transaction_id is not null and length(transaction_id) > 0 and paid_at is not null)
    or (status <> 'paid' and transaction_id is null and paid_at is null)
  ),
  constraint payment_orders_expiry_check check (expires_at > created_at),
  constraint payment_orders_org_request_unique unique (organization_id, request_key)
);

create unique index if not exists payment_orders_provider_transaction_unique
  on public.payment_orders(mch_id, transaction_id) where transaction_id is not null;
create index if not exists payment_orders_org_created_idx
  on public.payment_orders(organization_id, created_at desc);
create index if not exists payment_orders_pending_check_idx
  on public.payment_orders(updated_at, created_at) where status = 'pending';