# Copyright (C) 2012 Google Inc. All rights reserved.
# Copyright (C) 2012 Zoltan Horvath, Adobe Systems Incorporated. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
#     * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#     * Redistributions in binary form must reproduce the above
# copyright notice, this list of conditions and the following disclaimer
# in the documentation and/or other materials provided with the
# distribution.
#     * Neither the name of Google Inc. nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


import logging
import math
import re

from webkitpy.layout_tests.port.driver import DriverInput

DEFAULT_TEST_RUNNER_COUNT = 4

_log = logging.getLogger(__name__)


class PerfTestMetric(object):

    def __init__(self, metric, unit=None, iterations=None):
        # FIXME: Fix runner.js to report correct metric names
        self._iterations = iterations or []
        self._unit = unit or self.metric_to_unit(metric)
        self._metric = self.time_unit_to_metric(self._unit) if metric == 'Time' else metric

    def name(self):
        return self._metric

    def has_values(self):
        return bool(self._iterations)

    def append_group(self, group_values):
        assert isinstance(group_values, list)
        self._iterations.append(group_values)

    def grouped_iteration_values(self):
        return self._iterations

    def flattened_iteration_values(self):
        return [value for group_values in self._iterations for value in group_values]

    def unit(self):
        return self._unit

    @staticmethod
    def metric_to_unit(metric):
        assert metric in ('Time', 'Malloc', 'JSHeap')
        return 'ms' if metric == 'Time' else 'bytes'

    @staticmethod
    def time_unit_to_metric(unit):
        return {'fps': 'FrameRate', 'runs/s': 'Runs', 'ms': 'Time'}[unit]


class PerfTest(object):

    def __init__(self, port, test_name, test_path, test_runner_count=DEFAULT_TEST_RUNNER_COUNT):
        self._port = port
        self._test_name = test_name
        self._test_path = test_path
        self._description = None
        self._metrics = {}
        self._ordered_metrics_name = []
        self._test_runner_count = test_runner_count

    def test_name(self):
        return self._test_name

    def test_name_without_file_extension(self):
        return re.sub(r'\.\w+$', '', self.test_name())

    def test_path(self):
        return self._test_path

    def description(self):
        return self._description

    def _create_driver(self):
        return self._port.create_driver(worker_number=0, no_timeout=True)

    def run(self, time_out_ms):
        for _ in xrange(self._test_runner_count):
            driver = self._create_driver()
            try:
                if not self._run_with_driver(driver, time_out_ms):
                    return None
            finally:
                driver.stop()

        should_log = not self._port.get_option('profile')
        if should_log and self._description:
            _log.info('DESCRIPTION: %s', self._description)

        results = {}
        for metric_name in self._ordered_metrics_name:
            metric = self._metrics[metric_name]
            results[metric.name()] = metric.grouped_iteration_values()
            if should_log:
                legacy_chromium_bot_compatible_name = self.test_name_without_file_extension().replace('/', ': ')
                self.log_statistics(legacy_chromium_bot_compatible_name + ': ' + metric.name(),
                                    metric.flattened_iteration_values(), metric.unit())

        return results

    @staticmethod
    def log_statistics(test_name, values, unit):
        sorted_values = sorted(values)

        # Compute the mean and variance using Knuth's online algorithm (has good numerical stability).
        square_sum = 0
        mean = 0
        for i, time in enumerate(sorted_values):
            delta = time - mean
            sweep = i + 1.0
            mean += delta / sweep
            square_sum += delta * (time - mean)

        middle = int(len(sorted_values) / 2)
        mean = sum(sorted_values) / len(values)
        median = sorted_values[middle] if len(sorted_values) % 2 else (sorted_values[middle - 1] + sorted_values[middle]) / 2
        stdev = math.sqrt(square_sum / (len(sorted_values) - 1)) if len(sorted_values) > 1 else 0

        _log.info('RESULT %s= %s %s', test_name, mean, unit)
        _log.info('median= %s %s, stdev= %s %s, min= %s %s, max= %s %s',
                  median, unit, stdev, unit, sorted_values[0], unit, sorted_values[-1], unit)

    _description_regex = re.compile(r'^Description: (?P<description>.*)$', re.IGNORECASE)
    _metrics_regex = re.compile(r'^(?P<metric>Time|Malloc|JS Heap):')
    _statistics_keys = ['avg', 'median', 'stdev', 'min', 'max', 'unit', 'values']
    _score_regex = re.compile(r'^(?P<key>' + r'|'.join(_statistics_keys) + r')\s+(?P<value>([0-9\.]+(,\s+)?)+)\s*(?P<unit>.*)')
    _console_regex = re.compile(r'^CONSOLE (MESSAGE|WARNING):')

    def _run_with_driver(self, driver, time_out_ms):
        output = self.run_single(driver, self.test_path(), time_out_ms)
        self._filter_output(output)
        if self.run_failed(output):
            return False

        current_metric = None
        for line in re.split('\n', output.text):
            description_match = self._description_regex.match(line)
            metric_match = self._metrics_regex.match(line)
            score = self._score_regex.match(line)
            console_match = self._console_regex.match(line)

            if description_match:
                self._description = description_match.group('description')
            elif metric_match:
                current_metric = metric_match.group('metric').replace(' ', '')
            elif score:
                if score.group('key') != 'values':
                    continue

                metric = self._ensure_metrics(current_metric, score.group('unit'))
                metric.append_group(map(lambda value: float(value), score.group('value').split(', ')))
            elif console_match:
                # Ignore console messages such as deprecation warnings.
                continue
            else:
                _log.error('ERROR: ' + line)
                return False

        return True

    def _ensure_metrics(self, metric_name, unit=None):
        if metric_name not in self._metrics:
            self._metrics[metric_name] = PerfTestMetric(metric_name, unit)
            self._ordered_metrics_name.append(metric_name)
        return self._metrics[metric_name]

    def run_single(self, driver, test_path, time_out_ms, should_run_pixel_test=False):
        return driver.run_test(
            DriverInput(test_path,
                        time_out_ms,
                        image_hash=None,
                        should_run_pixel_test=should_run_pixel_test,
                        args=[]),
            stop_when_done=False)

    def run_failed(self, output):
        if output.error:
            _log.error('error: %s\n%s', self.test_name(), output.error)

        if output.text is None:
            pass
        elif output.timeout:
            _log.error('timeout: %s', self.test_name())
        elif output.crash:
            _log.error('crash: %s', self.test_name())
        else:
            return False

        return True

    @staticmethod
    def _should_ignore_line(regexps, line):
        if not line:
            return True
        for regexp in regexps:
            if regexp.search(line):
                return True
        return False

    _lines_to_ignore_in_stderr = [
        re.compile(r'^Unknown option:'),
        re.compile(r'^\[WARNING:proxy_service.cc'),
        re.compile(r'^\[INFO:'),
        # These stderr messages come from content_shell on Linux.
        re.compile(r'INFO:SkFontHost_fontconfig.cpp'),
        re.compile(r'Running without the SUID sandbox'),
        # crbug.com/345229
        re.compile(r'InitializeSandbox\(\) called with multiple threads in process gpu-process')]

    _lines_to_ignore_in_parser_result = [
        re.compile(r'^\s*Running \d+ times$'),
        re.compile(r'^\s*Ignoring warm-up '),
        re.compile(r'^\s*Info:'),
        re.compile(r'^\s*\d+(.\d+)?(\s*(runs\/s|ms|fps))?$'),
        # Following are for handle existing test like Dromaeo
        re.compile(re.escape("""main frame - has 1 onunload handler(s)""")),
        re.compile(re.escape("""frame "<!--framePath //<!--frame0-->-->" - has 1 onunload handler(s)""")),
        re.compile(re.escape("""frame "<!--framePath //<!--frame0-->/<!--frame0-->-->" - has 1 onunload handler(s)""")),
        # Following is for html5.html
        re.compile(re.escape("""Blocked access to external URL http://www.whatwg.org/specs/web-apps/current-work/""")),
        re.compile(
            r"CONSOLE MESSAGE: (line \d+: )?Blocked script execution in '[A-Za-z0-9\-\.:]+' "
            "because the document's frame is sandboxed and the 'allow-scripts' permission is not set."),
        re.compile(r"CONSOLE MESSAGE: (line \d+: )?Not allowed to load local resource"),
        # Dromaeo reports values for subtests. Ignore them for now.
        re.compile(r'(?P<name>.+): \[(?P<values>(\d+(.\d+)?,\s+)*\d+(.\d+)?)\]'),
    ]

    def _filter_output(self, output):
        if output.error:
            output.error = '\n'.join([line for line in re.split('\n', output.error)
                                      if not self._should_ignore_line(self._lines_to_ignore_in_stderr, line)])
        if output.text:
            output.text = '\n'.join([line for line in re.split('\n', output.text)
                                     if not self._should_ignore_line(self._lines_to_ignore_in_parser_result, line)])


class SingleProcessPerfTest(PerfTest):

    def __init__(self, port, test_name, test_path, test_runner_count=1):
        super(SingleProcessPerfTest, self).__init__(port, test_name, test_path, test_runner_count)


class ChromiumStylePerfTest(PerfTest):
    _chromium_style_result_regex = re.compile(r'^RESULT\s+(?P<name>[^=]+)\s*=\s+(?P<value>\d+(\.\d+)?)\s*(?P<unit>\w+)$')

    def __init__(self, port, test_name, test_path, test_runner_count=DEFAULT_TEST_RUNNER_COUNT):
        super(ChromiumStylePerfTest, self).__init__(port, test_name, test_path, test_runner_count)

    def run(self, time_out_ms):
        driver = self._create_driver()
        try:
            output = self.run_single(driver, self.test_path(), time_out_ms)
        finally:
            driver.stop()

        self._filter_output(output)
        if self.run_failed(output):
            return None

        return self.parse_and_log_output(output)

    def parse_and_log_output(self, output):
        test_failed = False
        results = {}
        for line in re.split('\n', output.text):
            resultLine = ChromiumStylePerfTest._chromium_style_result_regex.match(line)
            if resultLine:
                # FIXME: Store the unit
                results[resultLine.group('name').replace(' ', '')] = float(resultLine.group('value'))
                _log.info(line)
            elif not len(line) == 0:
                test_failed = True
                _log.error(line)
        return results if results and not test_failed else None


class PerfTestFactory(object):

    _pattern_map = [
        (re.compile(r'^Dromaeo/'), SingleProcessPerfTest),
        (re.compile(r'^inspector/'), ChromiumStylePerfTest),
    ]

    @classmethod
    def create_perf_test(cls, port, test_name, path, test_runner_count=DEFAULT_TEST_RUNNER_COUNT):
        for (pattern, test_class) in cls._pattern_map:
            if pattern.match(test_name):
                return test_class(port, test_name, path, test_runner_count)
        return PerfTest(port, test_name, path, test_runner_count)