# Note: these tests are part of the self test, do not use or import pytest functionality here.
#       See borg.selftest for details. If you add/remove test methods, update SELFTEST_COUNT

"""
Self-testing module
===================

The selftest() function runs a small test suite of relatively fast tests that are meant to discover issues
with how Borg was compiled or packaged, as well as bugs in Borg itself.

These tests are a subset of borg/testsuite and are run with Python's built-in unittest; therefore none of
these tests can or should be ported to pytest at this time.

To ensure that self-test discovery works correctly, the expected number of tests is stored in
SELFTEST_COUNT. Update SELFTEST_COUNT whenever tests used here are added or removed.
"""

import os
import sys
import time
from unittest import TestResult, TestSuite, defaultTestLoader

from .testsuite.crypto.crypto_test import CryptoTestCase
from .testsuite.chunkers.buzhash_self_test import ChunkerTestCase
from .testsuite.chunkers.fixed_self_test import ChunkerFixedTestCase

SELFTEST_CASES = [CryptoTestCase, ChunkerTestCase, ChunkerFixedTestCase]

SELFTEST_COUNT = 17


class SelfTestResult(TestResult):
    def __init__(self):
        super().__init__()
        self.successes = []

    def addSuccess(self, test):
        super().addSuccess(test)
        self.successes.append(test)

    def test_name(self, test):
        return test.shortDescription() or str(test)

    def log_results(self, logger):
        for test, failure in self.errors + self.failures + self.unexpectedSuccesses:
            logger.error("self-test %s FAILED:\n%s", self.test_name(test), failure)
        for test, reason in self.skipped:
            logger.warning("self-test %s skipped: %s", self.test_name(test), reason)

    def successful_test_count(self):
        return len(self.successes)


def selftest(logger):
    if os.environ.get("BORG_SELFTEST") == "disabled":
        logger.debug("Borg self-test disabled via BORG_SELFTEST environment variable")
        return
    selftest_started = time.perf_counter()
    result = SelfTestResult()
    test_suite = TestSuite()
    for test_case in SELFTEST_CASES:
        module = sys.modules[test_case.__module__]
        # a normal borg user does not have pytest installed, we must not require it in the test modules used here.
        # note: this only detects the usual toplevel import
        assert "pytest" not in dir(module), "pytest must not be imported in %s" % module.__name__
        test_suite.addTest(defaultTestLoader.loadTestsFromTestCase(test_case))
    test_suite.run(result)
    result.log_results(logger)
    successful_tests = result.successful_test_count()
    count_mismatch = successful_tests != SELFTEST_COUNT
    if result.wasSuccessful() and count_mismatch:
        # only print this if all tests succeeded
        logger.error(
            "Self-test count (%d != %d) mismatch; either test discovery is broken, or a test was added "
            "without updating borg.selftest",
            successful_tests,
            SELFTEST_COUNT,
        )
    if not result.wasSuccessful() or count_mismatch:
        logger.error(
            "Self-test failed.\n"
            "This could be a bug in Borg, the package/distribution you use, your OS, or your hardware."
        )
        sys.exit(2)
        assert False, "sanity assertion failed: ran beyond sys.exit()"
    selftest_elapsed = time.perf_counter() - selftest_started
    logger.debug("%d self-tests completed in %.2f seconds", successful_tests, selftest_elapsed)