-- KNOWN ISSUE: cannot detect cases when rettype or argument type have same
--   name but the content changes (e.g. add a field in composite type)

SET client_min_messages to ERROR;
\x on
CREATE OR REPLACE FUNCTION filter_schema(argstr text, schema_name text)
RETURNS text AS $$
    if argstr is None:
        return "NULL"
    return argstr.replace(schema_name + ".", '')
$$ LANGUAGE plpythonu;


CREATE OR REPLACE FUNCTION get_functions(table_name text, schema_name text,
                                         type_filter text)
RETURNS VOID AS
$$
import plpy
column_name = plpy.execute("""
    SELECT column_name
    FROM information_schema.columns
    WHERE table_schema='pg_catalog' and table_name='pg_proc' and
        (column_name='prokind' or column_name='proisagg')
    """)[0]['column_name']
proisagg_wrapper = "p.proisagg" if column_name == 'proisagg' else "p.prokind = 'a'"
plpy.execute("""
    CREATE TABLE {table_name} AS
    SELECT
        "schema", "name", filter_schema("retype", '{schema_name}') retype,
        filter_schema("argtypes", '{schema_name}') argtypes, "type"
    FROM
    (

        SELECT n.nspname as "schema",
            p.proname as "name",
            CASE WHEN p.proretset THEN 'SETOF ' ELSE '' END ||
            pg_catalog.format_type(p.prorettype, NULL) as "retype",
            CASE WHEN proallargtypes IS NOT NULL THEN
                pg_catalog.array_to_string(ARRAY(
                    SELECT
                        pio || ptyp
                    FROM
                    (
                        SELECT
                            CASE
                              WHEN p.proargmodes[s.i] = 'i' THEN ''
                              WHEN p.proargmodes[s.i] = 'o' THEN 'OUT '
                              WHEN p.proargmodes[s.i] = 'b' THEN 'INOUT '
                              WHEN p.proargmodes[s.i] = 'v' THEN 'VARIADIC '
                            END  AS pio,
                        --CASE
                        --  WHEN COALESCE(p.proargnames[s.i], '') = '' THEN ''
                        --  ELSE p.proargnames[s.i] || ' '
                        --END ||
                        pg_catalog.format_type(p.proallargtypes[s.i], NULL) AS ptyp
                      FROM
                        pg_catalog.generate_series(1, pg_catalog.array_upper(p.proallargtypes, 1)) AS s(i)
                    ) qx
                    WHERE pio = ''
                    ), ', ')
            ELSE
                pg_catalog.array_to_string(ARRAY(
                  SELECT
                    --CASE
                    --  WHEN COALESCE(p.proargnames[s.i+1], '') = '' THEN ''
                    --  ELSE p.proargnames[s.i+1] || ' '
                    --  END ||
                    pg_catalog.format_type(p.proargtypes[s.i], NULL)
                  FROM
                    pg_catalog.generate_series(0, pg_catalog.array_upper(p.proargtypes, 1)) AS s(i)
                ), ', ')
            END AS "argtypes",
            CASE
              WHEN {proisagg_wrapper} THEN 'agg'
              WHEN p.prorettype = 'pg_catalog.trigger'::pg_catalog.regtype THEN 'trigger'
              ELSE 'normal'
            END AS "type"
        FROM pg_catalog.pg_proc p
             LEFT JOIN pg_catalog.pg_namespace n
             ON n.oid = p.pronamespace
        WHERE n.nspname ~ '^({schema_name})$'
        ORDER BY 1, 2, 4
    ) q
    WHERE retype LIKE '{type_filter}' OR retype LIKE '{type_filter}[]'
    """.format(table_name=table_name, schema_name=schema_name,
        type_filter=type_filter, proisagg_wrapper=proisagg_wrapper))
$$ LANGUAGE plpythonu;


DROP TABLE IF EXISTS functions_madlib_old_version;
DROP TABLE IF EXISTS functions_madlib_new_version;

SELECT get_functions('functions_madlib_old_version','madlib_old_vers','%');
SELECT get_functions('functions_madlib_new_version','madlib','%');

SELECT
    type,
    --'\t-' || name || ':' || '\n\t\t-rettype: ' || retype || '\n\t\t-argument: ' || argtypes
    '   - ' || name || ':' AS "Dropped UDF part1",
    '       rettype: ' || retype AS "Dropped UDF part2",
    '       argument: ' || argtypes AS "Dropped UDF part3"

FROM
(
SELECT
    old_version.name, old_version.retype, old_version.argtypes, old_version.type
FROM
    functions_madlib_old_version AS old_version
    LEFT JOIN
    functions_madlib_new_version AS new_version
    USING (name, retype, argtypes)
WHERE new_version.name IS NULL
) q
ORDER by type DESC, "Dropped UDF part1", "Dropped UDF part2", "Dropped UDF part3";

----------------------------------------

SELECT
    type,
    --'\t-' || name || ':' || '\n\t\t-rettype: ' || retype || '\n\t\t-argument: ' || argtypes
    '    - ' || name || ':' AS "Changed UDF part1",
    '        rettype: ' || retype AS "Changed UDF part2",
    '        argument: ' || argtypes AS "Changed UDF part3"
FROM
(
SELECT
    old_version.name, old_version.retype, old_version.argtypes, old_version.type
FROM
    functions_madlib_old_version AS old_version
    LEFT JOIN
    functions_madlib_new_version AS new_version
    USING (name, retype, argtypes)
-- WHERE FALSE
WHERE old_version.retype in ('') -- '__logregr_result', 'summary_result', 'linregr_result', 'mlogregr_result', 'marginal_logregr_result', 'marginal_mlogregr_result', 'intermediate_cox_prop_hazards_result', '__utils_scaled_data')
) q
ORDER by type DESC, "Changed UDF part1", "Changed UDF part2", "Changed UDF part3";

----------------------------------------

SELECT
    type,
    --'\t-' || name || ':' || '\n\t\t-rettype: ' || retype || '\n\t\t-argument: ' || argtypes
    '    - ' || name || ':' AS "Suspected UDF part1",
    '        rettype: ' || retype AS "Suspected UDF part2",
    '        argument: ' || argtypes AS "Suspected UDF part3"
FROM
(
SELECT
    old_version.name, old_version.retype, old_version.argtypes, old_version.type
FROM
    functions_madlib_old_version AS old_version
    LEFT JOIN
    functions_madlib_new_version AS new_version
    USING (name, retype, argtypes)
WHERE old_version.argtypes SIMILAR TO 'NOT-A-TYPE' -- '%(__logregr_result|summary_result|linregr_result|mlogregr_result|marginal_logregr_result|marginal_mlogregr_result|intermediate_cox_prop_hazards_result|__utils_scaled_data)%'
) q
ORDER by type DESC, "Suspected UDF part1", "Suspected UDF part2", "Suspected UDF part3";