mte/include/sql/exchange_do_lookup_kyc_requirement_by_row.sql

--
-- This file is part of TALER
-- Copyright (C) 2024 Taler Systems SA
--
-- TALER is free software; you can redistribute it and/or modify it under the
-- terms of the GNU General Public License as published by the Free Software
-- Foundation; either version 3, or (at your option) any later version.
--
-- TALER is distributed in the hope that it will be useful, but WITHOUT ANY
-- WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
-- A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
--
-- You should have received a copy of the GNU General Public License along with
-- TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
--
-- @author: Christian Grothoff

DROP FUNCTION IF EXISTS exchange_do_lookup_kyc_requirement_by_row;

CREATE FUNCTION exchange_do_lookup_kyc_requirement_by_row(
  IN in_h_normalized_payto BYTEA,
  IN in_account_pub BYTEA, -- NULL allowed
  OUT out_account_pub BYTEA,  -- NULL allowed
  OUT out_reserve_pub BYTEA, -- NULL allowed
  OUT out_access_token BYTEA, -- NULL if 'out_not_found'
  OUT out_jrules JSONB, -- NULL allowed
  OUT out_is_wallet BOOLEAN, -- NULL allowed
  OUT out_not_found BOOLEAN,
  OUT out_rule_gen INT8, -- NULL allowed
  OUT out_aml_review BOOLEAN, -- NULL allowed
  OUT out_kyc_required BOOLEAN)
LANGUAGE plpgsql
AS $$
DECLARE
  my_wtrec RECORD;
  my_lorec RECORD;
  my_ok BOOL;
BEGIN

-- Find the access token and the current account public key.
SELECT access_token
      ,target_pub
      ,is_wallet
  INTO my_wtrec
  FROM kyc_targets
 WHERE h_normalized_payto=in_h_normalized_payto;

IF NOT FOUND
THEN
  -- RAISE WARNING 'kyc_target % not found', in_h_normalized_payto;
  -- Given that we don't recognize the normalized payto, there is no
  -- chance that we can match the incoming public key against anything,
  -- so this is a 404-case.
  out_not_found = TRUE;
  out_kyc_required = FALSE;
  RETURN;
END IF;

my_ok = (in_account_pub IS NOT NULL) AND
        (my_wtrec.target_pub = in_account_pub);

IF ( (NOT my_ok) AND
     (in_account_pub IS NOT NULL) )
THEN
  -- RAISE WARNING 'target_pub % does not match', in_account_pub;
  -- We were given an in_account_pub, but it did not match the
  -- target pub.
  -- Try to see if the in_account_pub appears in ANY reserve_in
  -- for this account instead.
  PERFORM
     FROM reserves_in
    WHERE reserve_pub=in_account_pub
      AND wire_source_h_payto IN
     (SELECT wire_target_h_payto
        FROM wire_targets
       WHERE h_normalized_payto=in_h_normalized_payto);
  IF FOUND
  THEN
    my_wtrec.target_pub = in_account_pub;
    my_ok = TRUE;
  END IF;
END IF;

IF (NOT my_ok AND
    ( (in_account_pub IS NOT NULL) OR
      (my_wtrec.target_pub IS NULL) ) )
THEN
  -- We failed to find a matching public key for in_account_pub, and
  -- either the client provided a specific one to match OR
  -- we could not return any one that could even work, which means
  -- we are lacking the KYC auth or any even a triggered requirement.
  out_not_found = TRUE;
  out_kyc_required = FALSE;
  RETURN;
END IF;

-- We have found "something", which may or may not match the input
-- public key (if there was one), but at least some KYC requirement
-- exists.
out_not_found = FALSE;

out_is_wallet = my_wtrec.is_wallet;
out_account_pub = my_wtrec.target_pub;
out_access_token = my_wtrec.access_token;

-- RAISE WARNING 'account_pub established, checking measures for %', out_access_token;

-- Check if there are active measures for the account.
PERFORM
  FROM legitimization_measures
 WHERE access_token=out_access_token
   AND NOT is_finished
 LIMIT 1;

out_kyc_required = FOUND;

-- Get currently applicable rules.
-- Only one should ever be active per account.
SELECT jnew_rules
      ,to_investigate
      ,outcome_serial_id
  INTO my_lorec
  FROM legitimization_outcomes
 WHERE h_payto=in_h_normalized_payto
   AND is_active;

IF FOUND
THEN
  out_jrules=my_lorec.jnew_rules;
  out_aml_review=my_lorec.to_investigate;
  out_rule_gen=my_lorec.outcome_serial_id;
END IF;

-- Check most recent reserve_in wire transfer, we also
-- allow that reserve public key for authentication!
-- Only needed for old wallets that don't pass
-- in the account pub explicitly.
SELECT reserve_pub
  INTO out_reserve_pub
  FROM reserves_in
 WHERE wire_source_h_payto
   IN (SELECT wt.wire_target_h_payto
         FROM wire_targets wt
        WHERE h_normalized_payto=in_h_normalized_payto)
 ORDER BY execution_date DESC, reserve_in_serial_id DESC
 LIMIT 1;

END $$;