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lib/supabase/migrations/20260928160000_create_client_with_profile_link.sql

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+-- Legt einen neuen clients-Datensatz an und verknüpft ihn atomar mit profiles.client_id.
+-- Der "where client_id is null"-Guard verhindert, dass zwei parallele Submits
+-- jeweils einen eigenen clients-Datensatz erzeugen und verwaisen lassen.
+create or replace function public.create_client_and_link_profile(
+  p_profile_id uuid,
+  p_company_name text,
+  p_legal_form text,
+  p_industry text,
+  p_vat_id text,
+  p_tax_number text,
+  p_commercial_register_number text,
+  p_street text,
+  p_postal_code text,
+  p_city text,
+  p_country char(2),
+  p_billing_street text,
+  p_billing_postal_code text,
+  p_billing_city text,
+  p_billing_country char(2),
+  p_contact_name text,
+  p_contact_position text,
+  p_contact_email text,
+  p_contact_phone text
+) returns uuid
+language plpgsql
+security definer
+set search_path = ''
+as $$
+declare
+  v_client_id uuid;
+  v_updated_rows int;
+begin
+  insert into public.clients (
+    company_name, legal_form, industry, vat_id, tax_number, commercial_register_number,
+    street, postal_code, city, country,
+    billing_street, billing_postal_code, billing_city, billing_country,
+    contact_name, contact_position, contact_email, contact_phone
+  ) values (
+    p_company_name, p_legal_form, p_industry, p_vat_id, p_tax_number, p_commercial_register_number,
+    p_street, p_postal_code, p_city, p_country,
+    p_billing_street, p_billing_postal_code, p_billing_city, p_billing_country,
+    p_contact_name, p_contact_position, p_contact_email, p_contact_phone
+  )
+  returning id into v_client_id;
+
+  update public.profiles
+  set client_id = v_client_id
+  where id = p_profile_id
+    and client_id is null;
+
+  get diagnostics v_updated_rows = row_count;
+
+  if v_updated_rows = 0 then
+    raise exception 'profile already linked to a client' using errcode = '23505';
+  end if;
+
+  return v_client_id;
+end;
+$$;
+
+revoke execute on function public.create_client_and_link_profile(
+  uuid, text, text, text, text, text, text, text, text, text, char(2),
+  text, text, text, char(2), text, text, text, text
+) from public, anon;
+
+grant execute on function public.create_client_and_link_profile(
+  uuid, text, text, text, text, text, text, text, text, text, char(2),
+  text, text, text, char(2), text, text, text, text
+) to authenticated;