#!/usr/bin/env python

# Copyright 2014 Hewlett-Packard Development Company, L.P.
# Copyright 2014 Samsung Electronics
# All Rights Reserved.
#
# 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.

"""Trace a subunit stream in reasonable detail and high accuracy."""

import argparse
import datetime
import functools
import os
import re
import sys

import subunit
import testtools

# NOTE(mtreinish) on python3 anydbm was renamed dbm and the python2 dbm module
# was renamed to dbm.ndbm, this block takes that into account
try:
    import anydbm as dbm
except ImportError:
    import dbm

DAY_SECONDS = 60 * 60 * 24
FAILS = []
RESULTS = {}


def total_seconds(timedelta):
    # NOTE(mtreinish): This method is built-in to the timedelta class in
    # python >= 2.7 it is here to enable it's use on older versions
    return ((timedelta.days * DAY_SECONDS + timedelta.seconds) * 10 ** 6 +
            timedelta.microseconds) / 10 ** 6


def cleanup_test_name(name, strip_tags=True, strip_scenarios=False):
    """Clean up the test name for display.

    By default we strip out the tags in the test because they don't help us
    in identifying the test that is run to it's result.

    Make it possible to strip out the testscenarios information (not to
    be confused with tempest scenarios) however that's often needed to
    indentify generated negative tests.
    """
    if strip_tags:
        tags_start = name.find('[')
        tags_end = name.find(']')
        if tags_start > 0 and tags_end > tags_start:
            newname = name[:tags_start]
            newname += name[tags_end + 1:]
            name = newname

    if strip_scenarios:
        tags_start = name.find('(')
        tags_end = name.find(')')
        if tags_start > 0 and tags_end > tags_start:
            newname = name[:tags_start]
            newname += name[tags_end + 1:]
            name = newname

    return name


def get_duration(timestamps):
    start, end = timestamps
    if not start or not end:
        duration = ''
    else:
        delta = end - start
        duration = '%d.%06ds' % (
            delta.days * DAY_SECONDS + delta.seconds, delta.microseconds)
    return duration


def find_worker(test):
    """Get the worker number.

    If there are no workers because we aren't in a concurrent environment,
    assume the worker number is 0.
    """
    for tag in test['tags']:
        if tag.startswith('worker-'):
            return int(tag[7:])
    return 0


# Print out stdout/stderr if it exists, always
def print_attachments(stream, test, all_channels=False):
    """Print out subunit attachments.

    Print out subunit attachments that contain content. This
    runs in 2 modes, one for successes where we print out just stdout
    and stderr, and an override that dumps all the attachments.
    """
    channels = ('stdout', 'stderr')
    for name, detail in test['details'].items():
        # NOTE(sdague): the subunit names are a little crazy, and actually
        # are in the form pythonlogging:'' (with the colon and quotes)
        name = name.split(':')[0]
        if detail.content_type.type == 'test':
            detail.content_type.type = 'text'
        if (all_channels or name in channels) and detail.as_text():
            title = "Captured %s:" % name
            stream.write("\n%s\n%s\n" % (title, ('~' * len(title))))
            # indent attachment lines 4 spaces to make them visually
            # offset
            for line in detail.as_text().split('\n'):
                stream.write("    %s\n" % line)


def find_test_run_time_diff(test_id, run_time):
    times_db_path = os.path.join(os.path.join(os.getcwd(), '.testrepository'),
                                 'times.dbm')
    if os.path.isfile(times_db_path):
        try:
            test_times = dbm.open(times_db_path)
        except Exception:
            return False
        try:
            avg_runtime = float(test_times.get(str(test_id), False))
        except Exception:
            try:
                avg_runtime = float(test_times[str(test_id)])
            except Exception:
                avg_runtime = False

        if avg_runtime and avg_runtime > 0:
            run_time = float(run_time.rstrip('s'))
            perc_diff = ((run_time - avg_runtime) / avg_runtime) * 100
            return perc_diff
    return False


def show_outcome(stream, test, print_failures=False, failonly=False,
                 enable_diff=False, threshold='0'):
    global RESULTS
    status = test['status']
    # TODO(sdague): ask lifeless why on this?
    if status == 'exists':
        return

    worker = find_worker(test)
    name = cleanup_test_name(test['id'])
    duration = get_duration(test['timestamps'])

    if worker not in RESULTS:
        RESULTS[worker] = []
    RESULTS[worker].append(test)

    # don't count the end of the return code as a fail
    if name == 'process-returncode':
        return

    if status == 'fail':
        FAILS.append(test)
        stream.write('{%s} %s [%s] ... FAILED\n' % (
            worker, name, duration))
        if not print_failures:
            print_attachments(stream, test, all_channels=True)
    elif not failonly:
        if status == 'success':
            out_string = '{%s} %s [%s' % (worker, name, duration)
            perc_diff = find_test_run_time_diff(test['id'], duration)
            if enable_diff:
                if perc_diff and abs(perc_diff) >= abs(float(threshold)):
                    if perc_diff > 0:
                        out_string = out_string + ' +%.2f%%' % perc_diff
                    else:
                        out_string = out_string + ' %.2f%%' % perc_diff
            stream.write(out_string + '] ... ok\n')
            print_attachments(stream, test)
        elif status == 'skip':
            stream.write('{%s} %s ... SKIPPED: %s\n' % (
                worker, name, test['details']['reason'].as_text()))
        else:
            stream.write('{%s} %s [%s] ... %s\n' % (
                worker, name, duration, test['status']))
            if not print_failures:
                print_attachments(stream, test, all_channels=True)

    stream.flush()


def print_fails(stream):
    """Print summary failure report.

    Currently unused, however there remains debate on inline vs. at end
    reporting, so leave the utility function for later use.
    """
    if not FAILS:
        return
    stream.write("\n==============================\n")
    stream.write("Failed %s tests - output below:" % len(FAILS))
    stream.write("\n==============================\n")
    for f in FAILS:
        stream.write("\n%s\n" % f['id'])
        stream.write("%s\n" % ('-' * len(f['id'])))
        print_attachments(stream, f, all_channels=True)
    stream.write('\n')


def count_tests(key, value):
    count = 0
    for k, v in RESULTS.items():
        for item in v:
            if key in item:
                if re.search(value, item[key]):
                    count += 1
    return count


def run_time():
    runtime = 0.0
    for k, v in RESULTS.items():
        for test in v:
            test_dur = get_duration(test['timestamps']).strip('s')
            # NOTE(toabctl): get_duration() can return an empty string
            # which leads to a ValueError when casting to float
            if test_dur:
                runtime += float(test_dur)
    return runtime


def worker_stats(worker):
    tests = RESULTS[worker]
    num_tests = len(tests)
    delta = tests[-1]['timestamps'][1] - tests[0]['timestamps'][0]
    return num_tests, delta


def print_summary(stream, elapsed_time):
    stream.write("\n======\nTotals\n======\n")
    stream.write("Ran: %s tests in %.4f sec.\n" % (
        count_tests('status', '.*'), total_seconds(elapsed_time)))
    stream.write(" - Passed: %s\n" % count_tests('status', '^success$'))
    stream.write(" - Skipped: %s\n" % count_tests('status', '^skip$'))
    stream.write(" - Expected Fail: %s\n" % count_tests('status', '^xfail$'))
    stream.write(" - Unexpected Success: %s\n" % count_tests('status',
                                                             '^uxsuccess$'))
    stream.write(" - Failed: %s\n" % count_tests('status', '^fail$'))
    stream.write("Sum of execute time for each test: %.4f sec.\n" % run_time())

    # we could have no results, especially as we filter out the process-codes
    if RESULTS:
        stream.write("\n==============\nWorker Balance\n==============\n")

        for w in range(max(RESULTS.keys()) + 1):
            if w not in RESULTS:
                stream.write(
                    " - WARNING: missing Worker %s! "
                    "Race in testr accounting.\n" % w)
            else:
                num, time = worker_stats(w)
                stream.write(" - Worker %s (%s tests) => %ss\n" %
                             (w, num, time))


def parse_args():
    parser = argparse.ArgumentParser()
    parser.add_argument('--no-failure-debug', '-n', action='store_true',
                        dest='print_failures', help='Disable printing failure '
                        'debug information in realtime')
    parser.add_argument('--fails', '-f', action='store_true',
                        dest='post_fails', help='Print failure debug '
                        'information after the stream is proccesed')
    parser.add_argument('--failonly', action='store_true',
                        dest='failonly', help="Don't print success items",
                        default=(
                            os.environ.get('TRACE_FAILONLY', False)
                            is not False))
    parser.add_argument('--perc-diff', '-d', action='store_true',
                        dest='enable_diff',
                        help="Print percent change in run time on each test ")
    parser.add_argument('--diff-threshold', '-t', dest='threshold',
                        help="Threshold to use for displaying percent change "
                             "from the avg run time. If one is not specified "
                             "the percent change will always be displayed")
    parser.add_argument('--no-summary', action='store_true',
                        help="Don't print the summary of the test run after "
                             " completes")
    return parser.parse_args()


def main():
    args = parse_args()
    stream = subunit.ByteStreamToStreamResult(
        sys.stdin, non_subunit_name='stdout')
    outcomes = testtools.StreamToDict(
        functools.partial(show_outcome, sys.stdout,
                          print_failures=args.print_failures,
                          failonly=args.failonly,
                          enable_diff=args.enable_diff))
    summary = testtools.StreamSummary()
    result = testtools.CopyStreamResult([outcomes, summary])
    result = testtools.StreamResultRouter(result)
    cat = subunit.test_results.CatFiles(sys.stdout)
    result.add_rule(cat, 'test_id', test_id=None)
    start_time = datetime.datetime.utcnow()
    result.startTestRun()
    try:
        stream.run(result)
    finally:
        result.stopTestRun()
    stop_time = datetime.datetime.utcnow()
    elapsed_time = stop_time - start_time

    if count_tests('status', '.*') == 0:
        print("The test run didn't actually run any tests")
        exit(1)
    if args.post_fails:
        print_fails(sys.stdout)
    if not args.no_summary:
        print_summary(sys.stdout, elapsed_time)
    exit(0 if summary.wasSuccessful() else 1)


if __name__ == '__main__':
    main()