# pysqlite2/test/userfunctions.py: tests for user-defined functions and
#                                  aggregates.
#
# Copyright (C) 2005-2007 Gerhard Häring <gh@ghaering.de>
#
# This file is part of pysqlite.
#
# This software is provided 'as-is', without any express or implied
# warranty.  In no event will the authors be held liable for any damages
# arising from the use of this software.
#
# Permission is granted to anyone to use this software for any purpose,
# including commercial applications, and to alter it and redistribute it
# freely, subject to the following restrictions:
#
# 1. The origin of this software must not be misrepresented; you must not
#    claim that you wrote the original software. If you use this software
#    in a product, an acknowledgment in the product documentation would be
#    appreciated but is not required.
# 2. Altered source versions must be plainly marked as such, and must not be
#    misrepresented as being the original software.
# 3. This notice may not be removed or altered from any source distribution.

import contextlib
import functools
import gc
import io
import re
import sys
import unittest
import unittest.mock
import sqlite3 as sqlite

from test.support import bigmemtest, catch_unraisable_exception
from .test_dbapi import cx_limit


def with_tracebacks(exc, regex="", name=""):
    """Convenience decorator for testing callback tracebacks."""
    def decorator(func):
        _regex = re.compile(regex) if regex else None
        @functools.wraps(func)
        def wrapper(self, *args, **kwargs):
            with catch_unraisable_exception() as cm:
                # First, run the test with traceback enabled.
                with check_tracebacks(self, cm, exc, _regex, name):
                    func(self, *args, **kwargs)

            # Then run the test with traceback disabled.
            func(self, *args, **kwargs)
        return wrapper
    return decorator


@contextlib.contextmanager
def check_tracebacks(self, cm, exc, regex, obj_name):
    """Convenience context manager for testing callback tracebacks."""
    sqlite.enable_callback_tracebacks(True)
    try:
        buf = io.StringIO()
        with contextlib.redirect_stderr(buf):
            yield

        self.assertEqual(cm.unraisable.exc_type, exc)
        if regex:
            msg = str(cm.unraisable.exc_value)
            self.assertIsNotNone(regex.search(msg))
        if obj_name:
            self.assertEqual(cm.unraisable.object.__name__, obj_name)
    finally:
        sqlite.enable_callback_tracebacks(False)


def func_returntext():
    return "foo"
def func_returntextwithnull():
    return "1\x002"
def func_returnunicode():
    return "bar"
def func_returnint():
    return 42
def func_returnfloat():
    return 3.14
def func_returnnull():
    return None
def func_returnblob():
    return b"blob"
def func_returnlonglong():
    return 1<<31
def func_raiseexception():
    5/0
def func_memoryerror():
    raise MemoryError
def func_overflowerror():
    raise OverflowError

def func_isstring(v):
    return type(v) is str
def func_isint(v):
    return type(v) is int
def func_isfloat(v):
    return type(v) is float
def func_isnone(v):
    return type(v) is type(None)
def func_isblob(v):
    return isinstance(v, (bytes, memoryview))
def func_islonglong(v):
    return isinstance(v, int) and v >= 1<<31

def func(*args):
    return len(args)

class AggrNoStep:
    def __init__(self):
        pass

    def finalize(self):
        return 1

class AggrNoFinalize:
    def __init__(self):
        pass

    def step(self, x):
        pass

class AggrExceptionInInit:
    def __init__(self):
        5/0

    def step(self, x):
        pass

    def finalize(self):
        pass

class AggrExceptionInStep:
    def __init__(self):
        pass

    def step(self, x):
        5/0

    def finalize(self):
        return 42

class AggrExceptionInFinalize:
    def __init__(self):
        pass

    def step(self, x):
        pass

    def finalize(self):
        5/0

class AggrCheckType:
    def __init__(self):
        self.val = None

    def step(self, whichType, val):
        theType = {"str": str, "int": int, "float": float, "None": type(None),
                   "blob": bytes}
        self.val = int(theType[whichType] is type(val))

    def finalize(self):
        return self.val

class AggrCheckTypes:
    def __init__(self):
        self.val = 0

    def step(self, whichType, *vals):
        theType = {"str": str, "int": int, "float": float, "None": type(None),
                   "blob": bytes}
        for val in vals:
            self.val += int(theType[whichType] is type(val))

    def finalize(self):
        return self.val

class AggrSum:
    def __init__(self):
        self.val = 0.0

    def step(self, val):
        self.val += val

    def finalize(self):
        return self.val

class AggrText:
    def __init__(self):
        self.txt = ""
    def step(self, txt):
        self.txt = self.txt + txt
    def finalize(self):
        return self.txt


class FunctionTests(unittest.TestCase):
    def setUp(self):
        self.con = sqlite.connect(":memory:")

        self.con.create_function("returntext", 0, func_returntext)
        self.con.create_function("returntextwithnull", 0, func_returntextwithnull)
        self.con.create_function("returnunicode", 0, func_returnunicode)
        self.con.create_function("returnint", 0, func_returnint)
        self.con.create_function("returnfloat", 0, func_returnfloat)
        self.con.create_function("returnnull", 0, func_returnnull)
        self.con.create_function("returnblob", 0, func_returnblob)
        self.con.create_function("returnlonglong", 0, func_returnlonglong)
        self.con.create_function("raiseexception", 0, func_raiseexception)
        self.con.create_function("memoryerror", 0, func_memoryerror)
        self.con.create_function("overflowerror", 0, func_overflowerror)

        self.con.create_function("isstring", 1, func_isstring)
        self.con.create_function("isint", 1, func_isint)
        self.con.create_function("isfloat", 1, func_isfloat)
        self.con.create_function("isnone", 1, func_isnone)
        self.con.create_function("isblob", 1, func_isblob)
        self.con.create_function("islonglong", 1, func_islonglong)
        self.con.create_function("spam", -1, func)
        self.con.execute("create table test(t text)")

    def tearDown(self):
        self.con.close()

    def test_func_error_on_create(self):
        with self.assertRaises(sqlite.OperationalError):
            self.con.create_function("bla", -100, lambda x: 2*x)

    def test_func_too_many_args(self):
        category = sqlite.SQLITE_LIMIT_FUNCTION_ARG
        msg = "too many arguments on function"
        with cx_limit(self.con, category=category, limit=1):
            self.con.execute("select abs(-1)");
            with self.assertRaisesRegex(sqlite.OperationalError, msg):
                self.con.execute("select max(1, 2)");

    def test_func_ref_count(self):
        def getfunc():
            def f():
                return 1
            return f
        f = getfunc()
        globals()["foo"] = f
        # self.con.create_function("reftest", 0, getfunc())
        self.con.create_function("reftest", 0, f)
        cur = self.con.cursor()
        cur.execute("select reftest()")

    def test_func_return_text(self):
        cur = self.con.cursor()
        cur.execute("select returntext()")
        val = cur.fetchone()[0]
        self.assertEqual(type(val), str)
        self.assertEqual(val, "foo")

    def test_func_return_text_with_null_char(self):
        cur = self.con.cursor()
        res = cur.execute("select returntextwithnull()").fetchone()[0]
        self.assertEqual(type(res), str)
        self.assertEqual(res, "1\x002")

    def test_func_return_unicode(self):
        cur = self.con.cursor()
        cur.execute("select returnunicode()")
        val = cur.fetchone()[0]
        self.assertEqual(type(val), str)
        self.assertEqual(val, "bar")

    def test_func_return_int(self):
        cur = self.con.cursor()
        cur.execute("select returnint()")
        val = cur.fetchone()[0]
        self.assertEqual(type(val), int)
        self.assertEqual(val, 42)

    def test_func_return_float(self):
        cur = self.con.cursor()
        cur.execute("select returnfloat()")
        val = cur.fetchone()[0]
        self.assertEqual(type(val), float)
        if val < 3.139 or val > 3.141:
            self.fail("wrong value")

    def test_func_return_null(self):
        cur = self.con.cursor()
        cur.execute("select returnnull()")
        val = cur.fetchone()[0]
        self.assertEqual(type(val), type(None))
        self.assertEqual(val, None)

    def test_func_return_blob(self):
        cur = self.con.cursor()
        cur.execute("select returnblob()")
        val = cur.fetchone()[0]
        self.assertEqual(type(val), bytes)
        self.assertEqual(val, b"blob")

    def test_func_return_long_long(self):
        cur = self.con.cursor()
        cur.execute("select returnlonglong()")
        val = cur.fetchone()[0]
        self.assertEqual(val, 1<<31)

    @with_tracebacks(ZeroDivisionError, name="func_raiseexception")
    def test_func_exception(self):
        cur = self.con.cursor()
        with self.assertRaises(sqlite.OperationalError) as cm:
            cur.execute("select raiseexception()")
            cur.fetchone()
        self.assertEqual(str(cm.exception), 'user-defined function raised exception')

    @with_tracebacks(MemoryError, name="func_memoryerror")
    def test_func_memory_error(self):
        cur = self.con.cursor()
        with self.assertRaises(MemoryError):
            cur.execute("select memoryerror()")
            cur.fetchone()

    @with_tracebacks(OverflowError, name="func_overflowerror")
    def test_func_overflow_error(self):
        cur = self.con.cursor()
        with self.assertRaises(sqlite.DataError):
            cur.execute("select overflowerror()")
            cur.fetchone()

    def test_param_string(self):
        cur = self.con.cursor()
        for text in ["foo", str()]:
            with self.subTest(text=text):
                cur.execute("select isstring(?)", (text,))
                val = cur.fetchone()[0]
                self.assertEqual(val, 1)

    def test_param_int(self):
        cur = self.con.cursor()
        cur.execute("select isint(?)", (42,))
        val = cur.fetchone()[0]
        self.assertEqual(val, 1)

    def test_param_float(self):
        cur = self.con.cursor()
        cur.execute("select isfloat(?)", (3.14,))
        val = cur.fetchone()[0]
        self.assertEqual(val, 1)

    def test_param_none(self):
        cur = self.con.cursor()
        cur.execute("select isnone(?)", (None,))
        val = cur.fetchone()[0]
        self.assertEqual(val, 1)

    def test_param_blob(self):
        cur = self.con.cursor()
        cur.execute("select isblob(?)", (memoryview(b"blob"),))
        val = cur.fetchone()[0]
        self.assertEqual(val, 1)

    def test_param_long_long(self):
        cur = self.con.cursor()
        cur.execute("select islonglong(?)", (1<<42,))
        val = cur.fetchone()[0]
        self.assertEqual(val, 1)

    def test_any_arguments(self):
        cur = self.con.cursor()
        cur.execute("select spam(?, ?)", (1, 2))
        val = cur.fetchone()[0]
        self.assertEqual(val, 2)

    def test_empty_blob(self):
        cur = self.con.execute("select isblob(x'')")
        self.assertTrue(cur.fetchone()[0])

    # Regarding deterministic functions:
    #
    # Between 3.8.3 and 3.15.0, deterministic functions were only used to
    # optimize inner loops, so for those versions we can only test if the
    # sqlite machinery has factored out a call or not. From 3.15.0 and onward,
    # deterministic functions were permitted in WHERE clauses of partial
    # indices, which allows testing based on syntax, iso. the query optimizer.
    @unittest.skipIf(sqlite.sqlite_version_info < (3, 8, 3), "Requires SQLite 3.8.3 or higher")
    def test_func_non_deterministic(self):
        mock = unittest.mock.Mock(return_value=None)
        self.con.create_function("nondeterministic", 0, mock, deterministic=False)
        if sqlite.sqlite_version_info < (3, 15, 0):
            self.con.execute("select nondeterministic() = nondeterministic()")
            self.assertEqual(mock.call_count, 2)
        else:
            with self.assertRaises(sqlite.OperationalError):
                self.con.execute("create index t on test(t) where nondeterministic() is not null")

    @unittest.skipIf(sqlite.sqlite_version_info < (3, 8, 3), "Requires SQLite 3.8.3 or higher")
    def test_func_deterministic(self):
        mock = unittest.mock.Mock(return_value=None)
        self.con.create_function("deterministic", 0, mock, deterministic=True)
        if sqlite.sqlite_version_info < (3, 15, 0):
            self.con.execute("select deterministic() = deterministic()")
            self.assertEqual(mock.call_count, 1)
        else:
            try:
                self.con.execute("create index t on test(t) where deterministic() is not null")
            except sqlite.OperationalError:
                self.fail("Unexpected failure while creating partial index")

    @unittest.skipIf(sqlite.sqlite_version_info >= (3, 8, 3), "SQLite < 3.8.3 needed")
    def test_func_deterministic_not_supported(self):
        with self.assertRaises(sqlite.NotSupportedError):
            self.con.create_function("deterministic", 0, int, deterministic=True)

    def test_func_deterministic_keyword_only(self):
        with self.assertRaises(TypeError):
            self.con.create_function("deterministic", 0, int, True)

    def test_function_destructor_via_gc(self):
        # See bpo-44304: The destructor of the user function can
        # crash if is called without the GIL from the gc functions
        dest = sqlite.connect(':memory:')
        def md5sum(t):
            return

        dest.create_function("md5", 1, md5sum)
        x = dest("create table lang (name, first_appeared)")
        del md5sum, dest

        y = [x]
        y.append(y)

        del x,y
        gc.collect()

    @with_tracebacks(OverflowError)
    def test_func_return_too_large_int(self):
        cur = self.con.cursor()
        for value in 2**63, -2**63-1, 2**64:
            self.con.create_function("largeint", 0, lambda value=value: value)
            with self.assertRaises(sqlite.DataError):
                cur.execute("select largeint()")

    @with_tracebacks(UnicodeEncodeError, "surrogates not allowed", "chr")
    def test_func_return_text_with_surrogates(self):
        cur = self.con.cursor()
        self.con.create_function("pychr", 1, chr)
        for value in 0xd8ff, 0xdcff:
            with self.assertRaises(sqlite.OperationalError):
                cur.execute("select pychr(?)", (value,))

    @unittest.skipUnless(sys.maxsize > 2**32, 'requires 64bit platform')
    @bigmemtest(size=2**31, memuse=3, dry_run=False)
    def test_func_return_too_large_text(self, size):
        cur = self.con.cursor()
        for size in 2**31-1, 2**31:
            self.con.create_function("largetext", 0, lambda size=size: "b" * size)
            with self.assertRaises(sqlite.DataError):
                cur.execute("select largetext()")

    @unittest.skipUnless(sys.maxsize > 2**32, 'requires 64bit platform')
    @bigmemtest(size=2**31, memuse=2, dry_run=False)
    def test_func_return_too_large_blob(self, size):
        cur = self.con.cursor()
        for size in 2**31-1, 2**31:
            self.con.create_function("largeblob", 0, lambda size=size: b"b" * size)
            with self.assertRaises(sqlite.DataError):
                cur.execute("select largeblob()")


class AggregateTests(unittest.TestCase):
    def setUp(self):
        self.con = sqlite.connect(":memory:")
        cur = self.con.cursor()
        cur.execute("""
            create table test(
                t text,
                i integer,
                f float,
                n,
                b blob
                )
            """)
        cur.execute("insert into test(t, i, f, n, b) values (?, ?, ?, ?, ?)",
            ("foo", 5, 3.14, None, memoryview(b"blob"),))

        self.con.create_aggregate("nostep", 1, AggrNoStep)
        self.con.create_aggregate("nofinalize", 1, AggrNoFinalize)
        self.con.create_aggregate("excInit", 1, AggrExceptionInInit)
        self.con.create_aggregate("excStep", 1, AggrExceptionInStep)
        self.con.create_aggregate("excFinalize", 1, AggrExceptionInFinalize)
        self.con.create_aggregate("checkType", 2, AggrCheckType)
        self.con.create_aggregate("checkTypes", -1, AggrCheckTypes)
        self.con.create_aggregate("mysum", 1, AggrSum)
        self.con.create_aggregate("aggtxt", 1, AggrText)

    def tearDown(self):
        #self.cur.close()
        #self.con.close()
        pass

    def test_aggr_error_on_create(self):
        with self.assertRaises(sqlite.OperationalError):
            self.con.create_function("bla", -100, AggrSum)

    def test_aggr_no_step(self):
        cur = self.con.cursor()
        with self.assertRaises(AttributeError) as cm:
            cur.execute("select nostep(t) from test")
        self.assertEqual(str(cm.exception), "'AggrNoStep' object has no attribute 'step'")

    def test_aggr_no_finalize(self):
        cur = self.con.cursor()
        with self.assertRaises(sqlite.OperationalError) as cm:
            cur.execute("select nofinalize(t) from test")
            val = cur.fetchone()[0]
        self.assertEqual(str(cm.exception), "user-defined aggregate's 'finalize' method raised error")

    @with_tracebacks(ZeroDivisionError, name="AggrExceptionInInit")
    def test_aggr_exception_in_init(self):
        cur = self.con.cursor()
        with self.assertRaises(sqlite.OperationalError) as cm:
            cur.execute("select excInit(t) from test")
            val = cur.fetchone()[0]
        self.assertEqual(str(cm.exception), "user-defined aggregate's '__init__' method raised error")

    @with_tracebacks(ZeroDivisionError, name="AggrExceptionInStep")
    def test_aggr_exception_in_step(self):
        cur = self.con.cursor()
        with self.assertRaises(sqlite.OperationalError) as cm:
            cur.execute("select excStep(t) from test")
            val = cur.fetchone()[0]
        self.assertEqual(str(cm.exception), "user-defined aggregate's 'step' method raised error")

    @with_tracebacks(ZeroDivisionError, name="AggrExceptionInFinalize")
    def test_aggr_exception_in_finalize(self):
        cur = self.con.cursor()
        with self.assertRaises(sqlite.OperationalError) as cm:
            cur.execute("select excFinalize(t) from test")
            val = cur.fetchone()[0]
        self.assertEqual(str(cm.exception), "user-defined aggregate's 'finalize' method raised error")

    def test_aggr_check_param_str(self):
        cur = self.con.cursor()
        cur.execute("select checkTypes('str', ?, ?)", ("foo", str()))
        val = cur.fetchone()[0]
        self.assertEqual(val, 2)

    def test_aggr_check_param_int(self):
        cur = self.con.cursor()
        cur.execute("select checkType('int', ?)", (42,))
        val = cur.fetchone()[0]
        self.assertEqual(val, 1)

    def test_aggr_check_params_int(self):
        cur = self.con.cursor()
        cur.execute("select checkTypes('int', ?, ?)", (42, 24))
        val = cur.fetchone()[0]
        self.assertEqual(val, 2)

    def test_aggr_check_param_float(self):
        cur = self.con.cursor()
        cur.execute("select checkType('float', ?)", (3.14,))
        val = cur.fetchone()[0]
        self.assertEqual(val, 1)

    def test_aggr_check_param_none(self):
        cur = self.con.cursor()
        cur.execute("select checkType('None', ?)", (None,))
        val = cur.fetchone()[0]
        self.assertEqual(val, 1)

    def test_aggr_check_param_blob(self):
        cur = self.con.cursor()
        cur.execute("select checkType('blob', ?)", (memoryview(b"blob"),))
        val = cur.fetchone()[0]
        self.assertEqual(val, 1)

    def test_aggr_check_aggr_sum(self):
        cur = self.con.cursor()
        cur.execute("delete from test")
        cur.executemany("insert into test(i) values (?)", [(10,), (20,), (30,)])
        cur.execute("select mysum(i) from test")
        val = cur.fetchone()[0]
        self.assertEqual(val, 60)

    def test_aggr_no_match(self):
        cur = self.con.execute("select mysum(i) from (select 1 as i) where i == 0")
        val = cur.fetchone()[0]
        self.assertIsNone(val)

    def test_aggr_text(self):
        cur = self.con.cursor()
        for txt in ["foo", "1\x002"]:
            with self.subTest(txt=txt):
                cur.execute("select aggtxt(?) from test", (txt,))
                val = cur.fetchone()[0]
                self.assertEqual(val, txt)


class AuthorizerTests(unittest.TestCase):
    @staticmethod
    def authorizer_cb(action, arg1, arg2, dbname, source):
        if action != sqlite.SQLITE_SELECT:
            return sqlite.SQLITE_DENY
        if arg2 == 'c2' or arg1 == 't2':
            return sqlite.SQLITE_DENY
        return sqlite.SQLITE_OK

    def setUp(self):
        self.con = sqlite.connect(":memory:")
        self.con.executescript("""
            create table t1 (c1, c2);
            create table t2 (c1, c2);
            insert into t1 (c1, c2) values (1, 2);
            insert into t2 (c1, c2) values (4, 5);
            """)

        # For our security test:
        self.con.execute("select c2 from t2")

        self.con.set_authorizer(self.authorizer_cb)

    def tearDown(self):
        pass

    def test_table_access(self):
        with self.assertRaises(sqlite.DatabaseError) as cm:
            self.con.execute("select * from t2")
        self.assertIn('prohibited', str(cm.exception))

    def test_column_access(self):
        with self.assertRaises(sqlite.DatabaseError) as cm:
            self.con.execute("select c2 from t1")
        self.assertIn('prohibited', str(cm.exception))

    def test_clear_authorizer(self):
        self.con.set_authorizer(None)
        self.con.execute("select * from t2")
        self.con.execute("select c2 from t1")


class AuthorizerRaiseExceptionTests(AuthorizerTests):
    @staticmethod
    def authorizer_cb(action, arg1, arg2, dbname, source):
        if action != sqlite.SQLITE_SELECT:
            raise ValueError
        if arg2 == 'c2' or arg1 == 't2':
            raise ValueError
        return sqlite.SQLITE_OK

    @with_tracebacks(ValueError, name="authorizer_cb")
    def test_table_access(self):
        super().test_table_access()

    @with_tracebacks(ValueError, name="authorizer_cb")
    def test_column_access(self):
        super().test_table_access()

class AuthorizerIllegalTypeTests(AuthorizerTests):
    @staticmethod
    def authorizer_cb(action, arg1, arg2, dbname, source):
        if action != sqlite.SQLITE_SELECT:
            return 0.0
        if arg2 == 'c2' or arg1 == 't2':
            return 0.0
        return sqlite.SQLITE_OK

class AuthorizerLargeIntegerTests(AuthorizerTests):
    @staticmethod
    def authorizer_cb(action, arg1, arg2, dbname, source):
        if action != sqlite.SQLITE_SELECT:
            return 2**32
        if arg2 == 'c2' or arg1 == 't2':
            return 2**32
        return sqlite.SQLITE_OK


if __name__ == "__main__":
    unittest.main()