#!/usr/bin/env python3

#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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
from argparse import ArgumentParser
import os
import re
import shutil
import subprocess
import sys
import tempfile
from threading import Thread, Lock
import time
import uuid
import queue as Queue
from multiprocessing import Manager


# Append `SPARK_HOME/dev` to the Python path so that we can import the sparktestsupport module
sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), "../dev/"))


from sparktestsupport import SPARK_HOME  # noqa (suppress pep8 warnings)
from sparktestsupport.shellutils import which, subprocess_check_output  # noqa
from sparktestsupport.modules import all_modules, pyspark_sql  # noqa


python_modules = dict((m.name, m) for m in all_modules if m.python_test_goals if m.name != 'root')


def print_red(text):
    print('\033[31m' + text + '\033[0m')


SKIPPED_TESTS = Manager().dict()
LOG_FILE = os.path.join(SPARK_HOME, "python/unit-tests.log")
FAILURE_REPORTING_LOCK = Lock()
LOGGER = logging.getLogger()

# Find out where the assembly jars are located.
# TODO: revisit for Scala 2.13
for scala in ["2.12"]:
    build_dir = os.path.join(SPARK_HOME, "assembly", "target", "scala-" + scala)
    if os.path.isdir(build_dir):
        SPARK_DIST_CLASSPATH = os.path.join(build_dir, "jars", "*")
        break
else:
    raise Exception("Cannot find assembly build directory, please build Spark first.")


def run_individual_python_test(target_dir, test_name, pyspark_python):
    env = dict(os.environ)
    env.update({
        'SPARK_DIST_CLASSPATH': SPARK_DIST_CLASSPATH,
        'SPARK_TESTING': '1',
        'SPARK_PREPEND_CLASSES': '1',
        'PYSPARK_PYTHON': which(pyspark_python),
        'PYSPARK_DRIVER_PYTHON': which(pyspark_python),
    })

    # Create a unique temp directory under 'target/' for each run. The TMPDIR variable is
    # recognized by the tempfile module to override the default system temp directory.
    tmp_dir = os.path.join(target_dir, str(uuid.uuid4()))
    while os.path.isdir(tmp_dir):
        tmp_dir = os.path.join(target_dir, str(uuid.uuid4()))
    os.mkdir(tmp_dir)
    env["TMPDIR"] = tmp_dir

    # Also override the JVM's temp directory by setting driver and executor options.
    java_options = "-Djava.io.tmpdir={0} -Dio.netty.tryReflectionSetAccessible=true".format(tmp_dir)
    spark_args = [
        "--conf", "spark.driver.extraJavaOptions='{0}'".format(java_options),
        "--conf", "spark.executor.extraJavaOptions='{0}'".format(java_options),
        "pyspark-shell"
    ]
    env["PYSPARK_SUBMIT_ARGS"] = " ".join(spark_args)

    LOGGER.info("Starting test(%s): %s", pyspark_python, test_name)
    start_time = time.time()
    try:
        per_test_output = tempfile.TemporaryFile()
        retcode = subprocess.Popen(
            [os.path.join(SPARK_HOME, "bin/pyspark")] + test_name.split(),
            stderr=per_test_output, stdout=per_test_output, env=env).wait()
        shutil.rmtree(tmp_dir, ignore_errors=True)
    except:
        LOGGER.exception("Got exception while running %s with %s", test_name, pyspark_python)
        # Here, we use os._exit() instead of sys.exit() in order to force Python to exit even if
        # this code is invoked from a thread other than the main thread.
        os._exit(1)
    duration = time.time() - start_time
    # Exit on the first failure.
    if retcode != 0:
        try:
            with FAILURE_REPORTING_LOCK:
                with open(LOG_FILE, 'ab') as log_file:
                    per_test_output.seek(0)
                    log_file.writelines(per_test_output)
                per_test_output.seek(0)
                for line in per_test_output:
                    decoded_line = line.decode("utf-8", "replace")
                    if not re.match('[0-9]+', decoded_line):
                        print(decoded_line, end='')
                per_test_output.close()
        except:
            LOGGER.exception("Got an exception while trying to print failed test output")
        finally:
            print_red("\nHad test failures in %s with %s; see logs." % (test_name, pyspark_python))
            # Here, we use os._exit() instead of sys.exit() in order to force Python to exit even if
            # this code is invoked from a thread other than the main thread.
            os._exit(-1)
    else:
        skipped_counts = 0
        try:
            per_test_output.seek(0)
            # Here expects skipped test output from unittest when verbosity level is
            # 2 (or --verbose option is enabled).
            decoded_lines = map(lambda line: line.decode("utf-8", "replace"), iter(per_test_output))
            skipped_tests = list(filter(
                lambda line: re.search(r'test_.* \(pyspark\..*\) ... (skip|SKIP)', line),
                decoded_lines))
            skipped_counts = len(skipped_tests)
            if skipped_counts > 0:
                key = (pyspark_python, test_name)
                SKIPPED_TESTS[key] = skipped_tests
            per_test_output.close()
        except:
            import traceback
            print_red("\nGot an exception while trying to store "
                      "skipped test output:\n%s" % traceback.format_exc())
            # Here, we use os._exit() instead of sys.exit() in order to force Python to exit even if
            # this code is invoked from a thread other than the main thread.
            os._exit(-1)
        if skipped_counts != 0:
            LOGGER.info(
                "Finished test(%s): %s (%is) ... %s tests were skipped", pyspark_python, test_name,
                duration, skipped_counts)
        else:
            LOGGER.info(
                "Finished test(%s): %s (%is)", pyspark_python, test_name, duration)


def get_default_python_executables():
    python_execs = [x for x in ["python3.6", "python3.8", "pypy3"] if which(x)]

    if "python3.6" not in python_execs:
        p = which("python3")
        if not p:
            LOGGER.error("No python3 executable found.  Exiting!")
            os._exit(1)
        else:
            python_execs.insert(0, p)
    return python_execs


def parse_opts():
    parser = ArgumentParser(
        prog="run-tests"
    )
    parser.add_argument(
        "--python-executables", type=str, default=','.join(get_default_python_executables()),
        help="A comma-separated list of Python executables to test against (default: %(default)s)"
    )
    parser.add_argument(
        "--modules", type=str,
        default=",".join(sorted(python_modules.keys())),
        help="A comma-separated list of Python modules to test (default: %(default)s)"
    )
    parser.add_argument(
        "-p", "--parallelism", type=int, default=4,
        help="The number of suites to test in parallel (default %(default)d)"
    )
    parser.add_argument(
        "--verbose", action="store_true",
        help="Enable additional debug logging"
    )

    group = parser.add_argument_group("Developer Options")
    group.add_argument(
        "--testnames", type=str,
        default=None,
        help=(
            "A comma-separated list of specific modules, classes and functions of doctest "
            "or unittest to test. "
            "For example, 'pyspark.sql.foo' to run the module as unittests or doctests, "
            "'pyspark.sql.tests FooTests' to run the specific class of unittests, "
            "'pyspark.sql.tests FooTests.test_foo' to run the specific unittest in the class. "
            "'--modules' option is ignored if they are given.")
    )

    args, unknown = parser.parse_known_args()
    if unknown:
        parser.error("Unsupported arguments: %s" % ' '.join(unknown))
    if args.parallelism < 1:
        parser.error("Parallelism cannot be less than 1")
    return args


def _check_coverage(python_exec):
    # Make sure if coverage is installed.
    try:
        subprocess_check_output(
            [python_exec, "-c", "import coverage"],
            stderr=open(os.devnull, 'w'))
    except:
        print_red("Coverage is not installed in Python executable '%s' "
                  "but 'COVERAGE_PROCESS_START' environment variable is set, "
                  "exiting." % python_exec)
        sys.exit(-1)


def main():
    opts = parse_opts()
    if opts.verbose:
        log_level = logging.DEBUG
    else:
        log_level = logging.INFO
    should_test_modules = opts.testnames is None
    logging.basicConfig(stream=sys.stdout, level=log_level, format="%(message)s")
    LOGGER.info("Running PySpark tests. Output is in %s", LOG_FILE)
    if os.path.exists(LOG_FILE):
        os.remove(LOG_FILE)
    python_execs = opts.python_executables.split(',')
    LOGGER.info("Will test against the following Python executables: %s", python_execs)

    if should_test_modules:
        modules_to_test = []
        for module_name in opts.modules.split(','):
            if module_name in python_modules:
                modules_to_test.append(python_modules[module_name])
            else:
                print("Error: unrecognized module '%s'. Supported modules: %s" %
                      (module_name, ", ".join(python_modules)))
                sys.exit(-1)
        LOGGER.info("Will test the following Python modules: %s", [x.name for x in modules_to_test])
    else:
        testnames_to_test = opts.testnames.split(',')
        LOGGER.info("Will test the following Python tests: %s", testnames_to_test)

    task_queue = Queue.PriorityQueue()
    for python_exec in python_execs:
        # Check if the python executable has coverage installed when 'COVERAGE_PROCESS_START'
        # environmental variable is set.
        if "COVERAGE_PROCESS_START" in os.environ:
            _check_coverage(python_exec)

        python_implementation = subprocess_check_output(
            [python_exec, "-c", "import platform; print(platform.python_implementation())"],
            universal_newlines=True).strip()
        LOGGER.info("%s python_implementation is %s", python_exec, python_implementation)
        LOGGER.info("%s version is: %s", python_exec, subprocess_check_output(
            [python_exec, "--version"], stderr=subprocess.STDOUT, universal_newlines=True).strip())
        if should_test_modules:
            for module in modules_to_test:
                if python_implementation not in module.blacklisted_python_implementations:
                    for test_goal in module.python_test_goals:
                        heavy_tests = ['pyspark.streaming.tests', 'pyspark.mllib.tests',
                                       'pyspark.tests', 'pyspark.sql.tests', 'pyspark.ml.tests']
                        if any(map(lambda prefix: test_goal.startswith(prefix), heavy_tests)):
                            priority = 0
                        else:
                            priority = 100
                        task_queue.put((priority, (python_exec, test_goal)))
        else:
            for test_goal in testnames_to_test:
                task_queue.put((0, (python_exec, test_goal)))

    # Create the target directory before starting tasks to avoid races.
    target_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), 'target'))
    if not os.path.isdir(target_dir):
        os.mkdir(target_dir)

    def process_queue(task_queue):
        while True:
            try:
                (priority, (python_exec, test_goal)) = task_queue.get_nowait()
            except Queue.Empty:
                break
            try:
                run_individual_python_test(target_dir, test_goal, python_exec)
            finally:
                task_queue.task_done()

    start_time = time.time()
    for _ in range(opts.parallelism):
        worker = Thread(target=process_queue, args=(task_queue,))
        worker.daemon = True
        worker.start()
    try:
        task_queue.join()
    except (KeyboardInterrupt, SystemExit):
        print_red("Exiting due to interrupt")
        sys.exit(-1)
    total_duration = time.time() - start_time
    LOGGER.info("Tests passed in %i seconds", total_duration)

    for key, lines in sorted(SKIPPED_TESTS.items()):
        pyspark_python, test_name = key
        LOGGER.info("\nSkipped tests in %s with %s:" % (test_name, pyspark_python))
        for line in lines:
            LOGGER.info("    %s" % line.rstrip())


if __name__ == "__main__":
    main()