--
-- This file is part of TALER
-- Copyright (C) 2014--2022 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/>
--

CREATE OR REPLACE FUNCTION create_table_kyc_attributes(
  IN partition_suffix VARCHAR DEFAULT NULL
)
RETURNS VOID
LANGUAGE plpgsql
AS $$
DECLARE
  table_name VARCHAR DEFAULT 'kyc_attributes';
BEGIN
  PERFORM create_partitioned_table(
    'CREATE TABLE IF NOT EXISTS %I'
      '(kyc_attributes_serial_id BIGINT GENERATED BY DEFAULT AS IDENTITY'
      ',h_payto BYTEA PRIMARY KEY CHECK (LENGTH(h_payto)=32)'
      ',kyc_prox BYTEA NOT NULL CHECK (LENGTH(kyc_prox)=32)'
      ',provider VARCHAR NOT NULL'
      ',birthdate VARCHAR'
      ',collection_time INT8 NOT NULL'
      ',expiration_time INT8 NOT NULL'
      ',encrypted_attributes BYTEA NOT NULL'
    ') %s ;'
    ,table_name
    ,'PARTITION BY HASH (h_payto)'
    ,partition_suffix
  );
  PERFORM comment_partitioned_table(
     'KYC data about particular payment addresses'
    ,table_name
    ,partition_suffix
  );
  PERFORM comment_partitioned_column(
     'hash of payto://-URI the attributes are about'
    ,'h_payto'
    ,table_name
    ,partition_suffix
  );
  PERFORM comment_partitioned_column(
     'short hash of normalized full name and birthdate; used to efficiently find likely duplicate users'
    ,'kyc_prox'
    ,table_name
    ,partition_suffix
  );
  PERFORM comment_partitioned_column(
     'birth date of the user, in format YYYY-MM-DD where a value of 0 is used to indicate unknown (in official documents); NULL if the birth date was not collected by the provider; used for KYC-driven age restrictions'
    ,'birthdate'
    ,table_name
    ,partition_suffix
  );
  PERFORM comment_partitioned_column(
     'time when the attributes were collected by the provider'
    ,'collection_time'
    ,table_name
    ,partition_suffix
  );
  PERFORM comment_partitioned_column(
     'time when the attributes should no longer be considered validated'
    ,'expiration_time'
    ,table_name
    ,partition_suffix
  );
  PERFORM comment_partitioned_column(
     'configuration section name of the provider that affirmed the attributes'
    ,'provider'
    ,table_name
    ,partition_suffix
  );
  PERFORM comment_partitioned_column(
     '(encrypted) JSON object (as string) with the attributes'
    ,'encrypted_attributes'
    ,table_name
    ,partition_suffix
  );
END $$;

COMMENT ON FUNCTION create_table_kyc_attributes
  IS 'Creates the kyc_attributes table';


CREATE OR REPLACE FUNCTION constrain_table_kyc_attributes(
  IN partition_suffix VARCHAR
)
RETURNS void
LANGUAGE plpgsql
AS $$
DECLARE
  table_name VARCHAR DEFAULT 'kyc_attributes';
BEGIN
  table_name = concat_ws('_', table_name, partition_suffix);
  EXECUTE FORMAT (
    'ALTER TABLE ' || table_name ||
      ' ADD CONSTRAINT ' || table_name || '_serial_key '
        'UNIQUE (kyc_attributes_serial_id)'
  );
  -- To search similar users (e.g. during AML checks)
  EXECUTE FORMAT (
    'CREATE INDEX ' || table_name || '_similarity_index '
    'ON ' || table_name || ' '
    '(kyc_prox);'
  );
  -- For garbage collection
  EXECUTE FORMAT (
    'CREATE INDEX ' || table_name || '_expiration_time '
    'ON ' || table_name || ' '
    '(expiration_time ASC);'
  );
END $$;


INSERT INTO exchange_tables
    (name
    ,version
    ,action
    ,partitioned
    ,by_range)
  VALUES
    ('kyc_attributes'
    ,'exchange-0003'
    ,'create'
    ,TRUE
    ,FALSE),
    ('kyc_attributes'
    ,'exchange-0003'
    ,'constrain'
    ,TRUE
    ,FALSE);
