#
# Copyright 2012 Facebook
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
from __future__ import absolute_import, division, print_function

import contextlib
import glob
import logging
import os
import re
import subprocess
import sys
import tempfile
import warnings

from tornado.escape import utf8
from tornado.log import LogFormatter, define_logging_options, enable_pretty_logging
from tornado.options import OptionParser
from tornado.test.util import unittest
from tornado.util import basestring_type


@contextlib.contextmanager
def ignore_bytes_warning():
    with warnings.catch_warnings():
        warnings.simplefilter('ignore', category=BytesWarning)
        yield


class LogFormatterTest(unittest.TestCase):
    # Matches the output of a single logging call (which may be multiple lines
    # if a traceback was included, so we use the DOTALL option)
    LINE_RE = re.compile(
        b"(?s)\x01\\[E [0-9]{6} [0-9]{2}:[0-9]{2}:[0-9]{2} log_test:[0-9]+\\]\x02 (.*)")

    def setUp(self):
        self.formatter = LogFormatter(color=False)
        # Fake color support.  We can't guarantee anything about the $TERM
        # variable when the tests are run, so just patch in some values
        # for testing.  (testing with color off fails to expose some potential
        # encoding issues from the control characters)
        self.formatter._colors = {
            logging.ERROR: u"\u0001",
        }
        self.formatter._normal = u"\u0002"
        # construct a Logger directly to bypass getLogger's caching
        self.logger = logging.Logger('LogFormatterTest')
        self.logger.propagate = False
        self.tempdir = tempfile.mkdtemp()
        self.filename = os.path.join(self.tempdir, 'log.out')
        self.handler = self.make_handler(self.filename)
        self.handler.setFormatter(self.formatter)
        self.logger.addHandler(self.handler)

    def tearDown(self):
        self.handler.close()
        os.unlink(self.filename)
        os.rmdir(self.tempdir)

    def make_handler(self, filename):
        # Base case: default setup without explicit encoding.
        # In python 2, supports arbitrary byte strings and unicode objects
        # that contain only ascii.  In python 3, supports ascii-only unicode
        # strings (but byte strings will be repr'd automatically).
        return logging.FileHandler(filename)

    def get_output(self):
        with open(self.filename, "rb") as f:
            line = f.read().strip()
            m = LogFormatterTest.LINE_RE.match(line)
            if m:
                return m.group(1)
            else:
                raise Exception("output didn't match regex: %r" % line)

    def test_basic_logging(self):
        self.logger.error("foo")
        self.assertEqual(self.get_output(), b"foo")

    def test_bytes_logging(self):
        with ignore_bytes_warning():
            # This will be "\xe9" on python 2 or "b'\xe9'" on python 3
            self.logger.error(b"\xe9")
            self.assertEqual(self.get_output(), utf8(repr(b"\xe9")))

    def test_utf8_logging(self):
        with ignore_bytes_warning():
            self.logger.error(u"\u00e9".encode("utf8"))
        if issubclass(bytes, basestring_type):
            # on python 2, utf8 byte strings (and by extension ascii byte
            # strings) are passed through as-is.
            self.assertEqual(self.get_output(), utf8(u"\u00e9"))
        else:
            # on python 3, byte strings always get repr'd even if
            # they're ascii-only, so this degenerates into another
            # copy of test_bytes_logging.
            self.assertEqual(self.get_output(), utf8(repr(utf8(u"\u00e9"))))

    def test_bytes_exception_logging(self):
        try:
            raise Exception(b'\xe9')
        except Exception:
            self.logger.exception('caught exception')
        # This will be "Exception: \xe9" on python 2 or
        # "Exception: b'\xe9'" on python 3.
        output = self.get_output()
        self.assertRegexpMatches(output, br'Exception.*\\xe9')
        # The traceback contains newlines, which should not have been escaped.
        self.assertNotIn(br'\n', output)


class UnicodeLogFormatterTest(LogFormatterTest):
    def make_handler(self, filename):
        # Adding an explicit encoding configuration allows non-ascii unicode
        # strings in both python 2 and 3, without changing the behavior
        # for byte strings.
        return logging.FileHandler(filename, encoding="utf8")

    def test_unicode_logging(self):
        self.logger.error(u"\u00e9")
        self.assertEqual(self.get_output(), utf8(u"\u00e9"))


class EnablePrettyLoggingTest(unittest.TestCase):
    def setUp(self):
        super(EnablePrettyLoggingTest, self).setUp()
        self.options = OptionParser()
        define_logging_options(self.options)
        self.logger = logging.Logger('tornado.test.log_test.EnablePrettyLoggingTest')
        self.logger.propagate = False

    def test_log_file(self):
        tmpdir = tempfile.mkdtemp()
        try:
            self.options.log_file_prefix = tmpdir + '/test_log'
            enable_pretty_logging(options=self.options, logger=self.logger)
            self.assertEqual(1, len(self.logger.handlers))
            self.logger.error('hello')
            self.logger.handlers[0].flush()
            filenames = glob.glob(tmpdir + '/test_log*')
            self.assertEqual(1, len(filenames))
            with open(filenames[0]) as f:
                self.assertRegexpMatches(f.read(), r'^\[E [^]]*\] hello$')
        finally:
            for handler in self.logger.handlers:
                handler.flush()
                handler.close()
            for filename in glob.glob(tmpdir + '/test_log*'):
                os.unlink(filename)
            os.rmdir(tmpdir)

    def test_log_file_with_timed_rotating(self):
        tmpdir = tempfile.mkdtemp()
        try:
            self.options.log_file_prefix = tmpdir + '/test_log'
            self.options.log_rotate_mode = 'time'
            enable_pretty_logging(options=self.options, logger=self.logger)
            self.logger.error('hello')
            self.logger.handlers[0].flush()
            filenames = glob.glob(tmpdir + '/test_log*')
            self.assertEqual(1, len(filenames))
            with open(filenames[0]) as f:
                self.assertRegexpMatches(
                    f.read(),
                    r'^\[E [^]]*\] hello$')
        finally:
            for handler in self.logger.handlers:
                handler.flush()
                handler.close()
            for filename in glob.glob(tmpdir + '/test_log*'):
                os.unlink(filename)
            os.rmdir(tmpdir)

    def test_wrong_rotate_mode_value(self):
        try:
            self.options.log_file_prefix = 'some_path'
            self.options.log_rotate_mode = 'wrong_mode'
            self.assertRaises(ValueError, enable_pretty_logging,
                              options=self.options, logger=self.logger)
        finally:
            for handler in self.logger.handlers:
                handler.flush()
                handler.close()


class LoggingOptionTest(unittest.TestCase):
    """Test the ability to enable and disable Tornado's logging hooks."""
    def logs_present(self, statement, args=None):
        # Each test may manipulate and/or parse the options and then logs
        # a line at the 'info' level.  This level is ignored in the
        # logging module by default, but Tornado turns it on by default
        # so it is the easiest way to tell whether tornado's logging hooks
        # ran.
        IMPORT = 'from tornado.options import options, parse_command_line'
        LOG_INFO = 'import logging; logging.info("hello")'
        program = ';'.join([IMPORT, statement, LOG_INFO])
        proc = subprocess.Popen(
            [sys.executable, '-c', program] + (args or []),
            stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
        stdout, stderr = proc.communicate()
        self.assertEqual(proc.returncode, 0, 'process failed: %r' % stdout)
        return b'hello' in stdout

    def test_default(self):
        self.assertFalse(self.logs_present('pass'))

    def test_tornado_default(self):
        self.assertTrue(self.logs_present('parse_command_line()'))

    def test_disable_command_line(self):
        self.assertFalse(self.logs_present('parse_command_line()',
                                           ['--logging=none']))

    def test_disable_command_line_case_insensitive(self):
        self.assertFalse(self.logs_present('parse_command_line()',
                                           ['--logging=None']))

    def test_disable_code_string(self):
        self.assertFalse(self.logs_present(
            'options.logging = "none"; parse_command_line()'))

    def test_disable_code_none(self):
        self.assertFalse(self.logs_present(
            'options.logging = None; parse_command_line()'))

    def test_disable_override(self):
        # command line trumps code defaults
        self.assertTrue(self.logs_present(
            'options.logging = None; parse_command_line()',
            ['--logging=info']))
