import weakref
from inspect import iscoroutinefunction

from sentry_sdk.hub import Hub, _should_send_default_pii
from sentry_sdk.utils import (
    HAS_REAL_CONTEXTVARS,
    event_from_exception,
    capture_internal_exceptions,
    transaction_from_function,
)
from sentry_sdk.integrations import Integration
from sentry_sdk.integrations._wsgi_common import (
    RequestExtractor,
    _filter_headers,
    _is_json_content_type,
)
from sentry_sdk.integrations.logging import ignore_logger

from tornado.web import RequestHandler, HTTPError  # type: ignore
from tornado.gen import coroutine  # type: ignore

if False:
    from typing import Any
    from typing import List
    from typing import Optional
    from typing import Dict
    from typing import Callable


class TornadoIntegration(Integration):
    identifier = "tornado"

    @staticmethod
    def setup_once():
        # type: () -> None
        import tornado  # type: ignore

        tornado_version = getattr(tornado, "version_info", None)
        if tornado_version is None or tornado_version < (5, 0):
            raise RuntimeError("Tornado 5+ required")

        if not HAS_REAL_CONTEXTVARS:
            # Tornado is async. We better have contextvars or we're going to leak
            # state between requests.
            raise RuntimeError(
                "The tornado integration for Sentry requires Python 3.6+ or the aiocontextvars package"
            )

        ignore_logger("tornado.application")
        ignore_logger("tornado.access")

        old_execute = RequestHandler._execute

        awaitable = iscoroutinefunction(old_execute)

        if awaitable:
            # Starting Tornado 6 RequestHandler._execute method is a standard Python coroutine (async/await)
            # In that case our method should be a coroutine function too
            async def sentry_execute_request_handler(self, *args, **kwargs):
                # type: (Any, *List, **Any) -> Any
                hub = Hub.current
                integration = hub.get_integration(TornadoIntegration)
                if integration is None:
                    return await old_execute(self, *args, **kwargs)

                weak_handler = weakref.ref(self)

                with Hub(hub) as hub:
                    with hub.configure_scope() as scope:
                        scope.clear_breadcrumbs()
                        scope.add_event_processor(_make_event_processor(weak_handler))
                    return await old_execute(self, *args, **kwargs)

        else:

            @coroutine  # type: ignore
            def sentry_execute_request_handler(self, *args, **kwargs):
                hub = Hub.current
                integration = hub.get_integration(TornadoIntegration)
                if integration is None:
                    return old_execute(self, *args, **kwargs)

                weak_handler = weakref.ref(self)

                with Hub(hub) as hub:
                    with hub.configure_scope() as scope:
                        scope.add_event_processor(_make_event_processor(weak_handler))
                    result = yield from old_execute(self, *args, **kwargs)
                    return result

        RequestHandler._execute = sentry_execute_request_handler

        old_log_exception = RequestHandler.log_exception

        def sentry_log_exception(self, ty, value, tb, *args, **kwargs):
            # type: (Any, type, BaseException, Any, *Any, **Any) -> Optional[Any]
            _capture_exception(ty, value, tb)
            return old_log_exception(self, ty, value, tb, *args, **kwargs)

        RequestHandler.log_exception = sentry_log_exception


def _capture_exception(ty, value, tb):
    # type: (type, BaseException, Any) -> None
    hub = Hub.current
    if hub.get_integration(TornadoIntegration) is None:
        return
    if isinstance(value, HTTPError):
        return

    event, hint = event_from_exception(
        (ty, value, tb),
        client_options=hub.client.options,
        mechanism={"type": "tornado", "handled": False},
    )

    hub.capture_event(event, hint=hint)


def _make_event_processor(weak_handler):
    # type: (Callable[[], RequestHandler]) -> Callable
    def tornado_processor(event, hint):
        # type: (Dict[str, Any], Dict[str, Any]) -> Dict[str, Any]
        handler = weak_handler()
        if handler is None:
            return event

        request = handler.request

        with capture_internal_exceptions():
            method = getattr(handler, handler.request.method.lower())
            event["transaction"] = transaction_from_function(method)

        with capture_internal_exceptions():
            extractor = TornadoRequestExtractor(request)
            extractor.extract_into_event(event)

            request_info = event["request"]

            request_info["url"] = "%s://%s%s" % (
                request.protocol,
                request.host,
                request.path,
            )

            request_info["query_string"] = request.query
            request_info["method"] = request.method
            request_info["env"] = {"REMOTE_ADDR": request.remote_ip}
            request_info["headers"] = _filter_headers(dict(request.headers))

        with capture_internal_exceptions():
            if handler.current_user and _should_send_default_pii():
                event.setdefault("user", {})["is_authenticated"] = True

        return event

    return tornado_processor


class TornadoRequestExtractor(RequestExtractor):
    def content_length(self):
        # type: () -> int
        if self.request.body is None:
            return 0
        return len(self.request.body)

    def cookies(self):
        # type: () -> Dict
        return {k: v.value for k, v in self.request.cookies.items()}

    def raw_data(self):
        # type: () -> bytes
        return self.request.body

    def form(self):
        # type: () -> Optional[Any]
        return {
            k: [v.decode("latin1", "replace") for v in vs]
            for k, vs in self.request.body_arguments.items()
        }

    def is_json(self):
        # type: () -> bool
        return _is_json_content_type(self.request.headers.get("content-type"))

    def files(self):
        # type: () -> Dict
        return {k: v[0] for k, v in self.request.files.items() if v}

    def size_of_file(self, file):
        return len(file.body or ())
