import types
from typing import Any
from typing import Dict
from typing import List
from typing import NamedTuple
from typing import Optional
from typing import Tuple

from atf_python.ktest import generate_ktests
from atf_python.utils import nodeid_to_method_name

import pytest
import os


class ATFCleanupItem(pytest.Item):
    def runtest(self):
        """Runs cleanup procedure for the test instead of the test itself"""
        instance = self.parent.cls()
        cleanup_name = "cleanup_{}".format(nodeid_to_method_name(self.nodeid))
        if hasattr(instance, cleanup_name):
            cleanup = getattr(instance, cleanup_name)
            cleanup(self.nodeid)
        elif hasattr(instance, "cleanup"):
            instance.cleanup(self.nodeid)

    def setup_method_noop(self, method):
        """Overrides runtest setup method"""
        pass

    def teardown_method_noop(self, method):
        """Overrides runtest teardown method"""
        pass


class ATFTestObj(object):
    def __init__(self, obj, has_cleanup):
        # Use nodeid without name to properly name class-derived tests
        self.ident = obj.nodeid.split("::", 1)[1]
        self.description = self._get_test_description(obj)
        self.has_cleanup = has_cleanup
        self.obj = obj

    def _get_test_description(self, obj):
        """Returns first non-empty line from func docstring or func name"""
        if getattr(obj, "descr", None) is not None:
            return getattr(obj, "descr")
        docstr = obj.function.__doc__
        if docstr:
            for line in docstr.split("\n"):
                if line:
                    return line
        return obj.name

    @staticmethod
    def _convert_user_mark(mark, obj, ret: Dict):
        username = mark.args[0]
        if username == "unprivileged":
            # Special unprivileged user requested.
            # First, require the unprivileged-user config option presence
            key = "require.config"
            if key not in ret:
                ret[key] = "unprivileged_user"
            else:
                ret[key] = "{} {}".format(ret[key], "unprivileged_user")
        # Check if the framework requires root
        test_cls = ATFHandler.get_test_class(obj)
        if test_cls and getattr(test_cls, "NEED_ROOT", False):
            # Yes, so we ask kyua to run us under root instead
            # It is up to the implementation to switch back to the desired
            # user
            ret["require.user"] = "root"
        else:
            ret["require.user"] = username

    def _convert_marks(self, obj) -> Dict[str, Any]:
        wj_func = lambda x: " ".join(x)  # noqa: E731
        _map: Dict[str, Dict] = {
            "require_user": {"handler": self._convert_user_mark},
            "require_arch": {"name": "require.arch", "fmt": wj_func},
            "require_diskspace": {"name": "require.diskspace"},
            "require_files": {"name": "require.files", "fmt": wj_func},
            "require_machine": {"name": "require.machine", "fmt": wj_func},
            "require_memory": {"name": "require.memory"},
            "require_progs": {"name": "require.progs", "fmt": wj_func},
            "timeout": {},
        }
        ret = {}
        for mark in obj.iter_markers():
            if mark.name in _map:
                if "handler" in _map[mark.name]:
                    _map[mark.name]["handler"](mark, obj, ret)
                    continue
                name = _map[mark.name].get("name", mark.name)
                if "fmt" in _map[mark.name]:
                    val = _map[mark.name]["fmt"](mark.args[0])
                else:
                    val = mark.args[0]
                ret[name] = val
        return ret

    def as_lines(self) -> List[str]:
        """Output test definition in ATF-specific format"""
        ret = []
        ret.append("ident: {}".format(self.ident))
        ret.append("descr: {}".format(self._get_test_description(self.obj)))
        if self.has_cleanup:
            ret.append("has.cleanup: true")
        for key, value in self._convert_marks(self.obj).items():
            ret.append("{}: {}".format(key, value))
        return ret


class ATFHandler(object):
    class ReportState(NamedTuple):
        state: str
        reason: str

    def __init__(self, report_file_name: Optional[str]):
        self._tests_state_map: Dict[str, ReportStatus] = {}
        self._report_file_name = report_file_name
        self._report_file_handle = None

    def setup_configure(self):
        fname = self._report_file_name
        if fname:
            self._report_file_handle = open(fname, mode="w")

    def setup_method_pre(self, item):
        """Called before actually running the test setup_method"""
        # Check if we need to manually drop the privileges
        for mark in item.iter_markers():
            if mark.name == "require_user":
                cls = self.get_test_class(item)
                cls.TARGET_USER = mark.args[0]
                break

    def override_runtest(self, obj):
        # Override basic runtest command
        obj.runtest = types.MethodType(ATFCleanupItem.runtest, obj)
        # Override class setup/teardown
        obj.parent.cls.setup_method = ATFCleanupItem.setup_method_noop
        obj.parent.cls.teardown_method = ATFCleanupItem.teardown_method_noop

    @staticmethod
    def get_test_class(obj):
        if hasattr(obj, "parent") and obj.parent is not None:
            if hasattr(obj.parent, "cls"):
                return obj.parent.cls

    def has_object_cleanup(self, obj):
        cls = self.get_test_class(obj)
        if cls is not None:
            method_name = nodeid_to_method_name(obj.nodeid)
            cleanup_name = "cleanup_{}".format(method_name)
            if hasattr(cls, "cleanup") or hasattr(cls, cleanup_name):
                return True
        return False

    def _generate_test_cleanups(self, items):
        new_items = []
        for obj in items:
            if self.has_object_cleanup(obj):
                self.override_runtest(obj)
                new_items.append(obj)
        items.clear()
        items.extend(new_items)

    def expand_tests(self, collector, name, obj):
        return generate_ktests(collector, name, obj)

    def modify_tests(self, items, config):
        if config.option.atf_cleanup:
            self._generate_test_cleanups(items)

    def list_tests(self, tests: List[str]):
        print('Content-Type: application/X-atf-tp; version="1"')
        print()
        for test_obj in tests:
            has_cleanup = self.has_object_cleanup(test_obj)
            atf_test = ATFTestObj(test_obj, has_cleanup)
            for line in atf_test.as_lines():
                print(line)
            print()

    def set_report_state(self, test_name: str, state: str, reason: str):
        self._tests_state_map[test_name] = self.ReportState(state, reason)

    def _extract_report_reason(self, report):
        data = report.longrepr
        if data is None:
            return None
        if isinstance(data, Tuple):
            # ('/path/to/test.py', 23, 'Skipped: unable to test')
            reason = data[2]
            for prefix in "Skipped: ":
                if reason.startswith(prefix):
                    reason = reason[len(prefix):]
            return reason
        else:
            # string/ traceback / exception report. Capture the last line
            return str(data).split("\n")[-1]
        return None

    def add_report(self, report):
        # MAP pytest report state to the atf-desired state
        #
        # ATF test states:
        # (1) expected_death, (2) expected_exit, (3) expected_failure
        # (4) expected_signal, (5) expected_timeout, (6) passed
        # (7) skipped, (8) failed
        #
        # Note that ATF don't have the concept of "soft xfail" - xpass
        # is a failure. It also calls teardown routine in a separate
        # process, thus teardown states (pytest-only) are handled as
        # body continuation.

        # (stage, state, wasxfail)

        # Just a passing test: WANT: passed
        # GOT: (setup, passed, F), (call, passed, F), (teardown, passed, F)
        #
        # Failing body test: WHAT: failed
        # GOT: (setup, passed, F), (call, failed, F), (teardown, passed, F)
        #
        # pytest.skip test decorator: WANT: skipped
        # GOT: (setup,skipped, False), (teardown, passed, False)
        #
        # pytest.skip call inside test function: WANT: skipped
        # GOT: (setup, passed, F), (call, skipped, F), (teardown,passed, F)
        #
        # mark.xfail decorator+pytest.xfail: WANT: expected_failure
        # GOT: (setup, passed, F), (call, skipped, T), (teardown, passed, F)
        #
        # mark.xfail decorator+pass: WANT: failed
        # GOT: (setup, passed, F), (call, passed, T), (teardown, passed, F)

        test_name = report.location[2]
        stage = report.when
        state = report.outcome
        reason = self._extract_report_reason(report)

        # We don't care about strict xfail - it gets translated to False

        if stage == "setup":
            if state in ("skipped", "failed"):
                # failed init -> failed test, skipped setup -> xskip
                # for the whole test
                self.set_report_state(test_name, state, reason)
        elif stage == "call":
            # "call" stage shouldn't matter if setup failed
            if test_name in self._tests_state_map:
                if self._tests_state_map[test_name].state == "failed":
                    return
            if state == "failed":
                # Record failure  & override "skipped" state
                self.set_report_state(test_name, state, reason)
            elif state == "skipped":
                if hasattr(reason, "wasxfail"):
                    # xfail() called in the test body
                    state = "expected_failure"
                else:
                    # skip inside the body
                    pass
                self.set_report_state(test_name, state, reason)
            elif state == "passed":
                if hasattr(reason, "wasxfail"):
                    # the test was expected to fail but didn't
                    # mark as hard failure
                    state = "failed"
                self.set_report_state(test_name, state, reason)
        elif stage == "teardown":
            if state == "failed":
                # teardown should be empty, as the cleanup
                # procedures should be implemented as a separate
                # function/method, so mark teardown failure as
                # global failure
                self.set_report_state(test_name, state, reason)

    def write_report(self):
        if self._report_file_handle is None:
            return
        if self._tests_state_map:
            # If we're executing in ATF mode, there has to be just one test
            # Anyway, deterministically pick the first one
            first_test_name = next(iter(self._tests_state_map))
            test = self._tests_state_map[first_test_name]
            if test.state == "passed":
                line = test.state
            else:
                line = "{}: {}".format(test.state, test.reason)
            print(line, file=self._report_file_handle)
        self._report_file_handle.close()

    @staticmethod
    def get_atf_vars() -> Dict[str, str]:
        px = "_ATF_VAR_"
        return {k[len(px):]: v for k, v in os.environ.items() if k.startswith(px)}