import shutil
import unittest
import os
import subprocess
from shutil import copyfile

import numpy as np
import pandas as pd
from pandas import DataFrame
from pandas.testing import assert_frame_equal, assert_series_equal
from io import StringIO
import tracemalloc
from typing import Final

# Make references to files and wikiq relative to this file, not to the current working directory.
TEST_DIR: Final[str] = os.path.dirname(os.path.realpath(__file__))
WIKIQ: Final[str] = os.path.join(os.path.dirname(TEST_DIR), "wikiq")
TEST_OUTPUT_DIR: Final[str] = os.path.join(TEST_DIR, "test_output")
BASELINE_DIR: Final[str] = os.path.join(TEST_DIR, "baseline_output")

IKWIKI: Final[str] = "ikwiki-20180301-pages-meta-history"
SAILORMOON: Final[str] = "sailormoon"
TWINPEAKS: Final[str] = "twinpeaks"
REGEXTEST: Final[str] = "regextest"


def setup():
    tracemalloc.start()

    # Perform directory check and reset here as this is a one-time setup step as opposed to per-test setup.
    if not os.path.exists(TEST_OUTPUT_DIR):
        os.mkdir(TEST_OUTPUT_DIR)


# Always run setup, even if this is executed via "python -m unittest" rather
# than as __main__.
setup()


class WikiqTester:
    def __init__(self,
                 wiki: str,
                 case_name: str,
                 suffix: str | None = None,
                 in_compression: str = "bz2",
                 baseline_format: str = "tsv",
                 out_format: str = "tsv",
                 ):
        self.input_file = os.path.join(TEST_DIR, "dumps", "{0}.xml.{1}".format(wiki, in_compression))

        basename = "{0}_{1}".format(case_name, wiki)
        if suffix:
            basename = "{0}_{1}".format(basename, suffix)

        self.output = os.path.join(TEST_OUTPUT_DIR, "{0}.{1}".format(basename, out_format))

        if os.path.exists(self.output):
            if os.path.isfile(self.output):
                os.remove(self.output)
            else:
                shutil.rmtree(self.output)

        if out_format == "parquet":
            os.makedirs(self.output, exist_ok=True)

        if suffix is None:
            self.wikiq_baseline_name = "{0}.{1}".format(wiki, baseline_format)
            self.wikiq_out_name = "{0}.{1}".format(wiki, out_format)
        else:
            self.wikiq_baseline_name = "{0}_{1}.{2}".format(wiki, suffix, baseline_format)
            self.wikiq_out_name = "{0}_{1}.{2}".format(wiki, suffix, out_format)

        # If case_name is unset, there are no relevant baseline or test files.
        if case_name is not None:
            self.baseline_file = os.path.join(BASELINE_DIR, "{0}_{1}".format(case_name, self.wikiq_baseline_name))

    def call_wikiq(self, *args: str, out: bool = True):
        """
        Calls wikiq with the passed arguments on the input file relevant to the test.
        :param args: The command line arguments to pass to wikiq.
        :param out: Whether to pass an output argument to wikiq.
        :return: The output of the wikiq call.
        """
        if out:
            call = ' '.join([WIKIQ, self.input_file, "-o", self.output, *args])
        else:
            call = ' '.join([WIKIQ, self.input_file, *args])

        print(call)
        return subprocess.check_output(call, stderr=subprocess.PIPE, shell=True)


# with / without pwr DONE
# with / without url encode DONE
# with / without collapse user DONE
# with output to stdout DONE
# note that the persistence radius is 7 by default
# reading various file formats including
#        7z, gz, bz2, xml  DONE
# wikia and wikipedia data DONE
# malformed xmls DONE

class WikiqTestCase(unittest.TestCase):
    def test_WP_noargs(self):
        tester = WikiqTester(IKWIKI, "noargs")

        try:
            tester.call_wikiq()
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        test = pd.read_table(tester.output)
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_WP_namespaces(self):
        tester = WikiqTester(IKWIKI, "namespaces")

        try:
            tester.call_wikiq("-n 0", "-n 1")
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        # as a test let's make sure that we get equal data frames
        test = pd.read_table(tester.output)
        num_wrong_ns = sum(~ test.namespace.isin({0, 1}))
        self.assertEqual(num_wrong_ns, 0)
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_WP_revert_radius(self):
        tester = WikiqTester(IKWIKI, "revert_radius")

        try:
            tester.call_wikiq("-n 0", "-n 1", "-rr 1")
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        # as a test let's make sure that we get equal data frames
        test = pd.read_table(tester.output)
        num_wrong_ns = sum(~ test.namespace.isin({0, 1}))
        self.assertEqual(num_wrong_ns, 0)
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_WP_no_revert_radius(self):
        tester = WikiqTester(IKWIKI, "no_revert_radius")

        try:
            tester.call_wikiq("-rr 0")
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        # as a test let's make sure that we get equal data frames
        test = pd.read_table(tester.output)
        num_reverted = sum(i is None for i in test.revert)
        self.assertEqual(num_reverted, 0)
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_WP_collapse_user(self):
        tester = WikiqTester(IKWIKI, "collapse_user")

        try:
            tester.call_wikiq("--collapse-user")
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        test = pd.read_table(tester.output)
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_noargs(self):
        tester = WikiqTester(SAILORMOON, "noargs", in_compression="7z")

        try:
            tester.call_wikiq()
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        test = pd.read_table(tester.output)
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_collapse_user(self):
        tester = WikiqTester(SAILORMOON, "collapse-user", in_compression="7z")

        try:
            tester.call_wikiq("--collapse-user", "--fandom-2020")
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        test = pd.read_table(tester.output)
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_pwr_segment(self):
        tester = WikiqTester(SAILORMOON, "persistence_segment", in_compression="7z")

        try:
            tester.call_wikiq("--persistence segment", "--fandom-2020")
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        test = pd.read_table(tester.output)
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_pwr_legacy(self):
        tester = WikiqTester(SAILORMOON, "persistence_legacy", in_compression="7z")

        try:
            tester.call_wikiq("--persistence legacy", "--fandom-2020")
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        test = pd.read_table(tester.output)
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_pwr(self):
        tester = WikiqTester(SAILORMOON, "persistence", in_compression="7z")

        try:
            tester.call_wikiq("--persistence", "--fandom-2020")
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        test = pd.read_table(tester.output)
        baseline = pd.read_table(tester.baseline_file)

        test = test.reindex(columns=sorted(test.columns))
        assert_frame_equal(test, baseline, check_like=True)

    def test_malformed_noargs(self):
        tester = WikiqTester(wiki=TWINPEAKS, case_name="noargs", in_compression="7z")
        want_exception = 'xml.etree.ElementTree.ParseError: no element found: line 1369, column 0'

        try:
            tester.call_wikiq()
        except subprocess.CalledProcessError as exc:
            errlines = exc.stderr.decode("utf8").splitlines()
            self.assertEqual(errlines[-1], want_exception)
        else:
            self.fail("No exception raised, want: {}".format(want_exception))

    def test_stdout_noargs(self):
        tester = WikiqTester(wiki=SAILORMOON, case_name="noargs", in_compression="7z")

        try:
            outs = tester.call_wikiq("--stdout", "--fandom-2020", out=False).decode("utf8")
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        test = pd.read_table(StringIO(outs))
        baseline = pd.read_table(tester.baseline_file)
        assert_frame_equal(test, baseline, check_like=True)

    def test_bad_regex(self):
        tester = WikiqTester(wiki=REGEXTEST, case_name="bad_regex")

        # sample arguments for checking that bad arguments get terminated / test_regex_arguments
        bad_arguments_list = [
            # label is missing
            "-RP '\\b\\d+\\b'",
            # number of reg and number of labels do not match
            "-RP 'NPO V' -RP THE -RPl testlabel",
            # cp but rp label
            "-CP '(Tamil|Li)' -RPl testlabel",
            # regex is missing
            "-CPl testlabel",
            "-RP '\\b\\w{3}\\b' -RPl threeletters -CP '\\b\\w{3}\\b'"
        ]

        for arguments in bad_arguments_list:
            try:
                tester.call_wikiq("--stdout", arguments, out=False)
            except subprocess.CalledProcessError as exc:
                # we want to check that the bad arguments were caught and sys.exit is stopping the code
                print(exc.stderr.decode("utf-8"))
            else:
                self.fail("No exception raised, want Exception")

    def test_good_regex(self):
        # sample arguments for checking the outcomes of good arguments / test_basic_regex
        good_arguments_list = [
            "-RP '\\b\\d{3}\\b' -RPl threedigits",
            "-RP 'TestCase' -RP 'page' -RPl testcases -RPl page_word",
            "-CP 'Chevalier' -CPl chev_com -RP 'welcome to Wikipedia' -RPl wiki_welcome -CP 'Warning' -CPl warning",
            "-CP 'WP:EVADE' -CPl wp_evade"
        ]

        for i, arguments in enumerate(good_arguments_list):
            tester = WikiqTester(wiki=REGEXTEST, case_name="basic", suffix=str(i))

            try:
                tester.call_wikiq(arguments)
            except subprocess.CalledProcessError as exc:
                self.fail(exc.stderr.decode("utf8"))

            test = pd.read_table(tester.output)

            baseline = pd.read_table(tester.baseline_file)
            assert_frame_equal(test, baseline, check_like=True)
            print(i)

    def test_capturegroup_regex(self):
        cap_arguments_list = [
            "-RP 'Li Chevalier' -RPl li_cheval -CP '(?P<letter>\\b[a-zA-Z]{3}\\b)|(?P<number>\\b\\d+\\b)|(?P<cat>\\bcat\\b)' -CPl three",
            "-CP '(?P<a>\\bTestCaseA\\b)|(?P<b>\\bTestCaseB\\b)|(?P<c>\\bTestCaseC\\b)|(?P<d>\\bTestCaseD\\b)' -CPl testcase -RP '(?P<npov>npov|NPOV)|(?P<neutral>neutral point of view)' -RPl npov"
        ]

        for i, arguments in enumerate(cap_arguments_list):
            tester = WikiqTester(wiki=REGEXTEST, case_name="capturegroup", suffix=str(i))

            try:
                tester.call_wikiq(arguments)
            except subprocess.CalledProcessError as exc:
                self.fail(exc.stderr.decode("utf8"))

            test = pd.read_table(tester.output)

            baseline = pd.read_table(tester.baseline_file)
            assert_frame_equal(test, baseline, check_like=True)

    def test_parquet(self):
        tester = WikiqTester(IKWIKI, "noargs", out_format="parquet")

        try:
            tester.call_wikiq()
        except subprocess.CalledProcessError as exc:
            self.fail(exc.stderr.decode("utf8"))

        # as a test let's make sure that we get equal data frames
        test: DataFrame = pd.read_parquet(tester.output)
        # test = test.drop(['reverteds'], axis=1)

        baseline: DataFrame = pd.read_table(tester.baseline_file)

        # Pandas does not read timestamps as the desired datetime type.
        baseline['date_time'] = pd.to_datetime(baseline['date_time'])
        # Split strings to the arrays of reverted IDs so they can be compared.
        baseline['revert'] = baseline['revert'].replace(np.nan, None)
        baseline['reverteds'] = baseline['reverteds'].replace(np.nan, None)
        # baseline['reverteds'] = [None if i is np.nan else [int(j) for j in str(i).split(",")] for i in baseline['reverteds']]
        baseline['sha1'] = baseline['sha1'].replace(np.nan, None)
        baseline['editor'] = baseline['editor'].replace(np.nan, None)
        baseline['anon'] = baseline['anon'].replace(np.nan, None)

        for index, row in baseline.iterrows():
            if row['editorid'] is None or test['editorid'][index] is None:
                if row['editorid'] != test['editorid'][index]:
                    print(row['revid'], ":", row['editorid'], "!=", test['editorid'][index])

        for col in baseline.columns:
            try:
                assert_series_equal(test[col], baseline[col], check_like=True, check_dtype=False)
            except ValueError as exc:
                print(f"Error comparing column {col}")
                self.fail(exc)

        # assert_frame_equal(test, baseline, check_like=True, check_dtype=False)


if __name__ == '__main__':
    unittest.main()