CREATE OR REPLACE FUNCTION pgtap_version()
RETURNS NUMERIC AS 'SELECT 1.1;'
LANGUAGE SQL IMMUTABLE;


-- These are now obsolete
DROP FUNCTION col_not_null ( NAME, NAME );
DROP FUNCTION col_is_null ( NAME, NAME, NAME );
DROP FUNCTION col_is_null ( NAME, NAME );

-- _col_is_null( schema, table, column, desc, null )
CREATE OR REPLACE FUNCTION _col_is_null ( NAME, NAME, NAME, TEXT, bool )
RETURNS TEXT AS $$
DECLARE
    qcol CONSTANT text := quote_ident($1) || '.' || quote_ident($2) || '.' || quote_ident($3);
    c_desc CONSTANT text := coalesce(
        $4,
        'Column ' || qcol || ' should '
            || CASE WHEN $5 THEN 'be NOT' ELSE 'allow' END || ' NULL'
    );
BEGIN
    IF NOT _cexists( $1, $2, $3 ) THEN
        RETURN fail( c_desc ) || E'\n'
            || diag ('    Column ' || qcol || ' does not exist' );
    END IF;
    RETURN ok(
        EXISTS(
            SELECT true
              FROM pg_catalog.pg_namespace n
              JOIN pg_catalog.pg_class c ON n.oid = c.relnamespace
              JOIN pg_catalog.pg_attribute a ON c.oid = a.attrelid
             WHERE n.nspname = $1
               AND c.relname = $2
               AND a.attnum  > 0
               AND NOT a.attisdropped
               AND a.attname    = $3
               AND a.attnotnull = $5
        ), c_desc
    );
END;
$$ LANGUAGE plpgsql;

-- _col_is_null( table, column, desc, null )
CREATE OR REPLACE FUNCTION _col_is_null ( NAME, NAME, TEXT, bool )
RETURNS TEXT AS $$
DECLARE
    qcol CONSTANT text := quote_ident($1) || '.' || quote_ident($2);
    c_desc CONSTANT text := coalesce(
        $3,
        'Column ' || qcol || ' should '
            || CASE WHEN $4 THEN 'be NOT' ELSE 'allow' END || ' NULL'
    );
BEGIN
    IF NOT _cexists( $1, $2 ) THEN
        RETURN fail( c_desc ) || E'\n'
            || diag ('    Column ' || qcol || ' does not exist' );
    END IF;
    RETURN ok(
        EXISTS(
            SELECT true
              FROM pg_catalog.pg_class c
              JOIN pg_catalog.pg_attribute a ON c.oid = a.attrelid
             WHERE pg_catalog.pg_table_is_visible(c.oid)
               AND c.relname = $1
               AND a.attnum > 0
               AND NOT a.attisdropped
               AND a.attname    = $2
               AND a.attnotnull = $4
        ), c_desc
    );
END;
$$ LANGUAGE plpgsql;

-- col_not_null( schema, table, column, description )
-- col_not_null( schema, table, column )
CREATE OR REPLACE FUNCTION col_not_null (
    schema_name NAME, table_name NAME, column_name NAME, description TEXT DEFAULT NULL
) RETURNS TEXT AS $$
    SELECT _col_is_null( $1, $2, $3, $4, true );
$$ LANGUAGE SQL;

-- col_not_null( table, column, description )
-- col_not_null( table, column )
CREATE OR REPLACE FUNCTION col_not_null (
    table_name NAME, column_name NAME, description TEXT DEFAULT NULL
) RETURNS TEXT AS $$
    SELECT _col_is_null( $1, $2, $3, true );
$$ LANGUAGE SQL;

-- col_is_null( schema, table, column, description )
-- col_is_null( schema, table, column )
CREATE OR REPLACE FUNCTION col_is_null (
    schema_name NAME, table_name NAME, column_name NAME, description TEXT DEFAULT NULL
) RETURNS TEXT AS $$
    SELECT _col_is_null( $1, $2, $3, $4, false );
$$ LANGUAGE SQL;

-- col_is_null( table, column, description )
-- col_is_null( table, column )
CREATE OR REPLACE FUNCTION col_is_null (
    table_name NAME, column_name NAME, description TEXT DEFAULT NULL
) RETURNS TEXT AS $$
    SELECT _col_is_null( $1, $2, $3, false );
$$ LANGUAGE SQL;

-- _keys( schema, table, constraint_type )
CREATE OR REPLACE FUNCTION _keys ( NAME, NAME, CHAR )
RETURNS SETOF NAME[] AS $$
    SELECT _pg_sv_column_array(x.conrelid,x.conkey) -- name[] doesn't support collation
      FROM pg_catalog.pg_namespace n
      JOIN pg_catalog.pg_class c       ON n.oid = c.relnamespace
      JOIN pg_catalog.pg_constraint x  ON c.oid = x.conrelid
     WHERE n.nspname = $1
       AND c.relname = $2
       AND x.contype = $3
  ORDER BY 1
$$ LANGUAGE sql;

-- _keys( table, constraint_type )
CREATE OR REPLACE FUNCTION _keys ( NAME, CHAR )
RETURNS SETOF NAME[] AS $$
    SELECT _pg_sv_column_array(x.conrelid,x.conkey) -- name[] doesn't support collation
      FROM pg_catalog.pg_class c
      JOIN pg_catalog.pg_constraint x  ON c.oid = x.conrelid
       AND c.relname = $1
       AND x.contype = $2
     WHERE pg_catalog.pg_table_is_visible(c.oid)
  ORDER BY 1
$$ LANGUAGE sql;


-- finish
DROP FUNCTION finish();
DROP FUNCTION _finish (INTEGER, INTEGER, INTEGER);

CREATE OR REPLACE FUNCTION _finish (INTEGER, INTEGER, INTEGER, BOOLEAN DEFAULT NULL)
RETURNS SETOF TEXT AS $$
DECLARE
    curr_test ALIAS FOR $1;
    exp_tests INTEGER := $2;
    num_faild ALIAS FOR $3;
    plural    CHAR;
    raise_ex  ALIAS FOR $4;
BEGIN
    plural    := CASE exp_tests WHEN 1 THEN '' ELSE 's' END;

    IF curr_test IS NULL THEN
        RAISE EXCEPTION '# No tests run!';
    END IF;

    IF exp_tests = 0 OR exp_tests IS NULL THEN
         -- No plan. Output one now.
        exp_tests = curr_test;
        RETURN NEXT '1..' || exp_tests;
    END IF;

    IF curr_test <> exp_tests THEN
        RETURN NEXT diag(
            'Looks like you planned ' || exp_tests || ' test' ||
            plural || ' but ran ' || curr_test
        );
    ELSIF num_faild > 0 THEN
        IF raise_ex THEN
            RAISE EXCEPTION  '% test% failed of %', num_faild, CASE num_faild WHEN 1 THEN '' ELSE 's' END, exp_tests;
        END IF;
        RETURN NEXT diag(
            'Looks like you failed ' || num_faild || ' test' ||
            CASE num_faild WHEN 1 THEN '' ELSE 's' END
            || ' of ' || exp_tests
        );
    ELSE

    END IF;
    RETURN;
END;
$$ LANGUAGE plpgsql;

CREATE OR REPLACE FUNCTION finish (exception_on_failure BOOLEAN DEFAULT NULL)
RETURNS SETOF TEXT AS $$
    SELECT * FROM _finish(
        _get('curr_test'),
        _get('plan'),
        num_failed(),
        $1
    );
$$ LANGUAGE sql;