liens

banque/banque.1.tables.sql

@@ -1,6 +1,9 @@
 drop schema if exists public cascade;
 create schema public;
 
+create schema if not exists ext;
+create extension if not exists pgcrypto schema ext;
+
 create type holder_type as enum ('BANK', 'PERSON', 'COMPANY');
 
 create table holder (
@@ -71,8 +74,10 @@ create table exchange_rate (
   primary key (currency_code, date)
 );
 
-create temporary table eurofxref (
-  "date" date,
+drop table if exists eurofxref;
+
+create temporary table if not exists eurofxref (
+  "date" date primary key,
   USD decimal, JPY decimal, BGN text, CYP text, CZK decimal,
   DKK decimal, EEK text, GBP decimal, HUF decimal, LTL text,
   LVL text, MTL text, PLN decimal, ROL text, RON text,
@@ -114,21 +119,56 @@ select rate
     limit 1;
 $$;
 
-/*
- * Account
- * La contrainte check (balance >= 0) empêche les soldes négatifs
- */
+-- Jeu de caractères utilisé 
+CREATE OR REPLACE FUNCTION chars36()
+RETURNS text AS $$
+    SELECT '12345ABCDE';
+$$ LANGUAGE sql IMMUTABLE;
+
+CREATE OR REPLACE FUNCTION char_to_int(c text)
+RETURNS int AS $$
+DECLARE
+    pos int;
+BEGIN
+    pos := position(c IN chars36()) - 1;
+    IF pos < 0 THEN
+        RAISE EXCEPTION 'Invalid base36 character: %', c;
+    END IF;
+    RETURN pos;
+END;
+$$ LANGUAGE plpgsql IMMUTABLE;
+
+CREATE OR REPLACE FUNCTION compute_checksum(code5 text)
+RETURNS text AS $$
+DECLARE
+    chars text := chars36();
+    weights int[] := ARRAY[7, 3, 1, 9, 11, 5];
+    total int := 0;
+    c text;
+    i int;
+BEGIN
+    
+    FOR i IN 1..length(code5) LOOP
+        c := substr(code5, i, 1);
+        total := total + char_to_int(c) * weights[i];
+    END LOOP;
+
+    total := total % length(chars);  
+    RETURN substr(chars, total + 1, 1);
+END;
+$$ LANGUAGE plpgsql IMMUTABLE;
 
 CREATE OR REPLACE FUNCTION rand_account(n integer)
 RETURNS text
 LANGUAGE plpgsql
 AS $$
 DECLARE
-  chars text := '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
+  chars text := chars36();
   out text := '';
-  b bytea := gen_random_bytes(n); -- n octets aléatoires
+  b bytea := ext.gen_random_bytes(n); -- n octets aléatoires
   i int;
   idx int;
+  check_char text;
 begin
   IF n <= 0 THEN
     RAISE EXCEPTION 'La longueur doit être > 0';
@@ -139,10 +179,45 @@ begin
     out := out || substr(chars, idx, 1);
   END LOOP;
 
-  RETURN out;
-END;
+  RETURN out || compute_checksum(out);
+end;
 $$;
 
+
+CREATE OR REPLACE FUNCTION is_valid_account_number(code text)
+RETURNS boolean AS $$
+DECLARE
+    base5 text;
+    given_checksum text;
+    expected_checksum text;
+BEGIN
+    -- 1. vérification format
+    IF code IS NULL OR length(code) <> 6 THEN
+        RETURN false;
+    END IF;
+
+    -- 2. séparation
+    base5 := upper(substr(code, 1, 5));     -- normalisation
+    given_checksum := upper(substr(code, 6, 1));
+
+    -- 3. validation caractères autorisés
+    IF base5 ~ '[^0-9A-Z]' OR given_checksum ~ '[^0-9A-Z]' THEN
+        RETURN false;
+    END IF;
+
+    -- 4. recalcul de la vraie clé de contrôle
+    expected_checksum := compute_checksum36(base5);
+
+    -- 5. comparaison
+    RETURN expected_checksum = given_checksum;
+END;
+$$ LANGUAGE plpgsql;
+
+/*
+ * Account
+ * La contrainte check (balance >= 0) empêche les soldes négatifs
+ */
+
 create table account (
   "id" bigint primary key generated always as identity,
   "opened_at" date not null default current_date,