# Copyright The OpenTelemetry Authors
#
# 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.

import logging
import os
import unittest
from unittest.mock import Mock, patch

from opentelemetry._logs import NoOpLoggerProvider, SeverityNumber
from opentelemetry._logs import get_logger as APIGetLogger
from opentelemetry.attributes import BoundedAttributes
from opentelemetry.sdk import trace
from opentelemetry.sdk._logs import (
    LogData,
    LoggerProvider,
    LoggingHandler,
    LogRecordProcessor,
)
from opentelemetry.sdk.environment_variables import OTEL_ATTRIBUTE_COUNT_LIMIT
from opentelemetry.semconv._incubating.attributes import code_attributes
from opentelemetry.semconv.attributes import exception_attributes
from opentelemetry.trace import (
    INVALID_SPAN_CONTEXT,
    set_span_in_context,
)


# pylint: disable=too-many-public-methods
class TestLoggingHandler(unittest.TestCase):
    def test_handler_default_log_level(self):
        processor, logger = set_up_test_logging(logging.NOTSET)

        # Make sure debug messages are ignored by default
        logger.debug("Debug message")
        assert processor.emit_count() == 0

        # Assert emit gets called for warning message
        with self.assertLogs(level=logging.WARNING):
            logger.warning("Warning message")
        self.assertEqual(processor.emit_count(), 1)

    def test_handler_custom_log_level(self):
        processor, logger = set_up_test_logging(logging.ERROR)

        with self.assertLogs(level=logging.WARNING):
            logger.warning("Warning message test custom log level")
        # Make sure any log with level < ERROR is ignored
        assert processor.emit_count() == 0

        with self.assertLogs(level=logging.ERROR):
            logger.error("Mumbai, we have a major problem")
        with self.assertLogs(level=logging.CRITICAL):
            logger.critical("No Time For Caution")
        self.assertEqual(processor.emit_count(), 2)

    # pylint: disable=protected-access
    def test_log_record_emit_noop(self):
        noop_logger_provder = NoOpLoggerProvider()
        logger_mock = APIGetLogger(
            __name__, logger_provider=noop_logger_provder
        )
        logger = logging.getLogger(__name__)
        handler_mock = Mock(spec=LoggingHandler)
        handler_mock._logger = logger_mock
        handler_mock.level = logging.WARNING
        logger.addHandler(handler_mock)
        with self.assertLogs(level=logging.WARNING):
            logger.warning("Warning message")

    def test_log_flush_noop(self):
        no_op_logger_provider = NoOpLoggerProvider()
        no_op_logger_provider.force_flush = Mock()

        logger = logging.getLogger("foo")
        handler = LoggingHandler(
            level=logging.NOTSET, logger_provider=no_op_logger_provider
        )
        logger.addHandler(handler)

        with self.assertLogs(level=logging.WARNING):
            logger.warning("Warning message")

        logger.handlers[0].flush()
        no_op_logger_provider.force_flush.assert_not_called()

    def test_log_record_no_span_context(self):
        processor, logger = set_up_test_logging(logging.WARNING)

        # Assert emit gets called for warning message
        with self.assertLogs(level=logging.WARNING):
            logger.warning("Warning message")

        log_record = processor.get_log_record(0)

        self.assertIsNotNone(log_record)
        self.assertEqual(log_record.trace_id, INVALID_SPAN_CONTEXT.trace_id)
        self.assertEqual(log_record.span_id, INVALID_SPAN_CONTEXT.span_id)
        self.assertEqual(
            log_record.trace_flags, INVALID_SPAN_CONTEXT.trace_flags
        )

    def test_log_record_observed_timestamp(self):
        processor, logger = set_up_test_logging(logging.WARNING)

        with self.assertLogs(level=logging.WARNING):
            logger.warning("Warning message")

        log_record = processor.get_log_record(0)
        self.assertIsNotNone(log_record.observed_timestamp)

    def test_log_record_user_attributes(self):
        """Attributes can be injected into logs by adding them to the LogRecord"""
        processor, logger = set_up_test_logging(logging.WARNING)

        # Assert emit gets called for warning message
        with self.assertLogs(level=logging.WARNING):
            logger.warning("Warning message", extra={"http.status_code": 200})

        log_record = processor.get_log_record(0)

        self.assertIsNotNone(log_record)
        self.assertEqual(len(log_record.attributes), 4)
        self.assertEqual(log_record.attributes["http.status_code"], 200)
        self.assertTrue(
            log_record.attributes[code_attributes.CODE_FILE_PATH].endswith(
                "test_handler.py"
            )
        )
        self.assertEqual(
            log_record.attributes[code_attributes.CODE_FUNCTION_NAME],
            "test_log_record_user_attributes",
        )
        # The line of the log statement is not a constant (changing tests may change that),
        # so only check that the attribute is present.
        self.assertTrue(
            code_attributes.CODE_LINE_NUMBER in log_record.attributes
        )
        self.assertTrue(isinstance(log_record.attributes, BoundedAttributes))

    def test_log_record_exception(self):
        """Exception information will be included in attributes"""
        processor, logger = set_up_test_logging(logging.ERROR)

        try:
            raise ZeroDivisionError("division by zero")
        except ZeroDivisionError:
            with self.assertLogs(level=logging.ERROR):
                logger.exception("Zero Division Error")

        log_record = processor.get_log_record(0)

        self.assertIsNotNone(log_record)
        self.assertTrue(isinstance(log_record.body, str))
        self.assertEqual(log_record.body, "Zero Division Error")
        self.assertEqual(
            log_record.attributes[exception_attributes.EXCEPTION_TYPE],
            ZeroDivisionError.__name__,
        )
        self.assertEqual(
            log_record.attributes[exception_attributes.EXCEPTION_MESSAGE],
            "division by zero",
        )
        stack_trace = log_record.attributes[
            exception_attributes.EXCEPTION_STACKTRACE
        ]
        self.assertIsInstance(stack_trace, str)
        self.assertTrue("Traceback" in stack_trace)
        self.assertTrue("ZeroDivisionError" in stack_trace)
        self.assertTrue("division by zero" in stack_trace)
        self.assertTrue(__file__ in stack_trace)

    def test_log_record_recursive_exception(self):
        """Exception information will be included in attributes even though it is recursive"""
        processor, logger = set_up_test_logging(logging.ERROR)

        try:
            raise ZeroDivisionError(
                ZeroDivisionError(ZeroDivisionError("division by zero"))
            )
        except ZeroDivisionError:
            with self.assertLogs(level=logging.ERROR):
                logger.exception("Zero Division Error")

        log_record = processor.get_log_record(0)

        self.assertIsNotNone(log_record)
        self.assertEqual(log_record.body, "Zero Division Error")
        self.assertEqual(
            log_record.attributes[exception_attributes.EXCEPTION_TYPE],
            ZeroDivisionError.__name__,
        )
        self.assertEqual(
            log_record.attributes[exception_attributes.EXCEPTION_MESSAGE],
            "division by zero",
        )
        stack_trace = log_record.attributes[
            exception_attributes.EXCEPTION_STACKTRACE
        ]
        self.assertIsInstance(stack_trace, str)
        self.assertTrue("Traceback" in stack_trace)
        self.assertTrue("ZeroDivisionError" in stack_trace)
        self.assertTrue("division by zero" in stack_trace)
        self.assertTrue(__file__ in stack_trace)

    def test_log_exc_info_false(self):
        """Exception information will not be included in attributes"""
        processor, logger = set_up_test_logging(logging.NOTSET)

        try:
            raise ZeroDivisionError("division by zero")
        except ZeroDivisionError:
            with self.assertLogs(level=logging.ERROR):
                logger.error("Zero Division Error", exc_info=False)

        log_record = processor.get_log_record(0)

        self.assertIsNotNone(log_record)
        self.assertEqual(log_record.body, "Zero Division Error")
        self.assertNotIn(
            exception_attributes.EXCEPTION_TYPE, log_record.attributes
        )
        self.assertNotIn(
            exception_attributes.EXCEPTION_MESSAGE, log_record.attributes
        )
        self.assertNotIn(
            exception_attributes.EXCEPTION_STACKTRACE, log_record.attributes
        )

    def test_log_record_exception_with_object_payload(self):
        processor, logger = set_up_test_logging(logging.ERROR)

        class CustomException(Exception):
            def __str__(self):
                return "CustomException stringified"

        try:
            raise CustomException("CustomException message")
        except CustomException as exception:
            with self.assertLogs(level=logging.ERROR):
                logger.exception(exception)

        log_record = processor.get_log_record(0)

        self.assertIsNotNone(log_record)
        self.assertTrue(isinstance(log_record.body, str))
        self.assertEqual(log_record.body, "CustomException stringified")
        self.assertEqual(
            log_record.attributes[exception_attributes.EXCEPTION_TYPE],
            CustomException.__name__,
        )
        self.assertEqual(
            log_record.attributes[exception_attributes.EXCEPTION_MESSAGE],
            "CustomException message",
        )
        stack_trace = log_record.attributes[
            exception_attributes.EXCEPTION_STACKTRACE
        ]
        self.assertIsInstance(stack_trace, str)
        self.assertTrue("Traceback" in stack_trace)
        self.assertTrue("CustomException" in stack_trace)
        self.assertTrue(__file__ in stack_trace)

    def test_log_record_trace_correlation(self):
        processor, logger = set_up_test_logging(logging.WARNING)

        tracer = trace.TracerProvider().get_tracer(__name__)
        with tracer.start_as_current_span("test") as span:
            mock_context = set_span_in_context(span)

            with patch(
                "opentelemetry.sdk._logs._internal.get_current",
                return_value=mock_context,
            ):
                with self.assertLogs(level=logging.CRITICAL):
                    logger.critical("Critical message within span")

                log_record = processor.get_log_record(0)

                self.assertEqual(
                    log_record.body, "Critical message within span"
                )
                self.assertEqual(log_record.severity_text, "CRITICAL")
                self.assertEqual(
                    log_record.severity_number, SeverityNumber.FATAL
                )
                self.assertEqual(log_record.context, mock_context)
                span_context = span.get_span_context()
                self.assertEqual(log_record.trace_id, span_context.trace_id)
                self.assertEqual(log_record.span_id, span_context.span_id)
                self.assertEqual(
                    log_record.trace_flags, span_context.trace_flags
                )

    def test_log_record_trace_correlation_deprecated(self):
        processor, logger = set_up_test_logging(logging.WARNING)

        tracer = trace.TracerProvider().get_tracer(__name__)
        with tracer.start_as_current_span("test") as span:
            with self.assertLogs(level=logging.CRITICAL):
                logger.critical("Critical message within span")

            log_record = processor.get_log_record(0)

            self.assertEqual(log_record.body, "Critical message within span")
            self.assertEqual(log_record.severity_text, "CRITICAL")
            self.assertEqual(log_record.severity_number, SeverityNumber.FATAL)
            span_context = span.get_span_context()
            self.assertEqual(log_record.trace_id, span_context.trace_id)
            self.assertEqual(log_record.span_id, span_context.span_id)
            self.assertEqual(log_record.trace_flags, span_context.trace_flags)

    def test_warning_without_formatter(self):
        processor, logger = set_up_test_logging(logging.WARNING)
        logger.warning("Test message")

        log_record = processor.get_log_record(0)
        self.assertEqual(log_record.body, "Test message")

    def test_exception_without_formatter(self):
        processor, logger = set_up_test_logging(logging.WARNING)
        logger.exception("Test exception")

        log_record = processor.get_log_record(0)
        self.assertEqual(log_record.body, "Test exception")

    def test_warning_with_formatter(self):
        processor, logger = set_up_test_logging(
            logging.WARNING,
            formatter=logging.Formatter(
                "%(name)s - %(levelname)s - %(message)s"
            ),
        )
        logger.warning("Test message")

        log_record = processor.get_log_record(0)
        self.assertEqual(log_record.body, "foo - WARNING - Test message")

    def test_log_body_is_always_string_with_formatter(self):
        processor, logger = set_up_test_logging(
            logging.WARNING,
            formatter=logging.Formatter(
                "%(name)s - %(levelname)s - %(message)s"
            ),
        )
        logger.warning(["something", "of", "note"])

        log_record = processor.get_log_record(0)
        self.assertIsInstance(log_record.body, str)

    @patch.dict(os.environ, {"OTEL_SDK_DISABLED": "true"})
    def test_handler_root_logger_with_disabled_sdk_does_not_go_into_recursion_error(
        self,
    ):
        processor, logger = set_up_test_logging(
            logging.NOTSET, root_logger=True
        )
        logger.warning("hello")

        self.assertEqual(processor.emit_count(), 0)

    @patch.dict(os.environ, {OTEL_ATTRIBUTE_COUNT_LIMIT: "3"})
    def test_otel_attribute_count_limit_respected_in_logging_handler(self):
        """Test that OTEL_ATTRIBUTE_COUNT_LIMIT is properly respected by LoggingHandler."""
        # Create a new LoggerProvider within the patched environment
        # This will create LogLimits() that reads from the environment variable
        logger_provider = LoggerProvider()
        processor = FakeProcessor()
        logger_provider.add_log_record_processor(processor)
        logger = logging.getLogger("env_test")
        handler = LoggingHandler(
            level=logging.WARNING, logger_provider=logger_provider
        )
        logger.addHandler(handler)

        # Create a log record with many extra attributes
        extra_attrs = {f"custom_attr_{i}": f"value_{i}" for i in range(10)}

        with self.assertLogs(level=logging.WARNING):
            logger.warning(
                "Test message with many attributes", extra=extra_attrs
            )

        log_record = processor.get_log_record(0)

        # With OTEL_ATTRIBUTE_COUNT_LIMIT=3, should have exactly 3 attributes
        total_attrs = len(log_record.attributes)
        self.assertEqual(
            total_attrs,
            3,
            f"Should have exactly 3 attributes due to limit, got {total_attrs}",
        )

        # Should have 10 dropped attributes (10 custom + 3 code - 3 kept = 10 dropped)
        self.assertEqual(
            log_record.dropped_attributes,
            10,
            f"Should have 10 dropped attributes, got {log_record.dropped_attributes}",
        )

    @patch.dict(os.environ, {OTEL_ATTRIBUTE_COUNT_LIMIT: "5"})
    def test_otel_attribute_count_limit_includes_code_attributes(self):
        """Test that OTEL_ATTRIBUTE_COUNT_LIMIT applies to all attributes including code attributes."""
        # Create a new LoggerProvider within the patched environment
        # This will create LogLimits() that reads from the environment variable
        logger_provider = LoggerProvider()
        processor = FakeProcessor()
        logger_provider.add_log_record_processor(processor)
        logger = logging.getLogger("env_test_2")
        handler = LoggingHandler(
            level=logging.WARNING, logger_provider=logger_provider
        )
        logger.addHandler(handler)

        # Create a log record with some extra attributes
        extra_attrs = {f"user_attr_{i}": f"value_{i}" for i in range(8)}

        with self.assertLogs(level=logging.WARNING):
            logger.warning("Test message", extra=extra_attrs)

        log_record = processor.get_log_record(0)

        # With OTEL_ATTRIBUTE_COUNT_LIMIT=5, should have exactly 5 attributes
        total_attrs = len(log_record.attributes)
        self.assertEqual(
            total_attrs,
            5,
            f"Should have exactly 5 attributes due to limit, got {total_attrs}",
        )

        # Should have 6 dropped attributes (8 user + 3 code - 5 kept = 6 dropped)
        self.assertEqual(
            log_record.dropped_attributes,
            6,
            f"Should have 6 dropped attributes, got {log_record.dropped_attributes}",
        )

    def test_logging_handler_without_env_var_uses_default_limit(self):
        """Test that without OTEL_ATTRIBUTE_COUNT_LIMIT, default limit (128) should apply."""
        processor, logger = set_up_test_logging(logging.WARNING)

        # Create a log record with many attributes (more than default limit of 128)
        extra_attrs = {f"attr_{i}": f"value_{i}" for i in range(150)}

        with self.assertLogs(level=logging.WARNING):
            logger.warning(
                "Test message with many attributes", extra=extra_attrs
            )

        log_record = processor.get_log_record(0)

        # Should be limited to default limit (128) total attributes
        total_attrs = len(log_record.attributes)
        self.assertEqual(
            total_attrs,
            128,
            f"Should have exactly 128 attributes (default limit), got {total_attrs}",
        )

        # Should have 25 dropped attributes (150 user + 3 code - 128 kept = 25 dropped)
        self.assertEqual(
            log_record.dropped_attributes,
            25,
            f"Should have 25 dropped attributes, got {log_record.dropped_attributes}",
        )


def set_up_test_logging(level, formatter=None, root_logger=False):
    logger_provider = LoggerProvider()
    processor = FakeProcessor()
    logger_provider.add_log_record_processor(processor)
    logger = logging.getLogger(None if root_logger else "foo")
    handler = LoggingHandler(level=level, logger_provider=logger_provider)
    if formatter:
        handler.setFormatter(formatter)
    logger.addHandler(handler)
    return processor, logger


class FakeProcessor(LogRecordProcessor):
    def __init__(self):
        self.log_data_emitted = []

    def on_emit(self, log_data: LogData):
        self.log_data_emitted.append(log_data)

    def shutdown(self):
        pass

    def force_flush(self, timeout_millis: int = 30000):
        pass

    def emit_count(self):
        return len(self.log_data_emitted)

    def get_log_record(self, i):
        return self.log_data_emitted[i].log_record
