#!/usr/bin/env python
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this file,
# You can obtain one at http://mozilla.org/MPL/2.0/.

import json
import os
import shutil
import sys
import tarfile
import tempfile
import zipfile
import uuid

import mozinfo
from mozharness.base.script import (
    PreScriptAction,
    PostScriptAction,
)
from mozharness.mozilla.testing.per_test_base import SingleTestMixin


_here = os.path.abspath(os.path.dirname(__file__))
_tooltool_path = os.path.normpath(os.path.join(_here, '..', '..', '..',
                                               'external_tools',
                                               'tooltool.py'))

code_coverage_config_options = [
    [["--code-coverage"],
     {"action": "store_true",
      "dest": "code_coverage",
      "default": False,
      "help": "Whether gcov c++ code coverage should be run."
      }],
    [["--per-test-coverage"],
     {"action": "store_true",
      "dest": "per_test_coverage",
      "default": False,
      "help": "Whether per-test coverage should be collected."
      }],
    [["--disable-ccov-upload"],
     {"action": "store_true",
      "dest": "disable_ccov_upload",
      "default": False,
      "help": "Whether test run should package and upload code coverage data."
      }],
    [["--jsd-code-coverage"],
     {"action": "store_true",
      "dest": "jsd_code_coverage",
      "default": False,
      "help": "Whether JSDebugger code coverage should be run."
      }],
]


class CodeCoverageMixin(SingleTestMixin):
    """
    Mixin for setting GCOV_PREFIX during test execution, packaging up
    the resulting .gcda files and uploading them to blobber.
    """
    gcov_dir = None
    jsvm_dir = None
    prefix = None
    per_test_reports = {}

    def __init__(self):
        super(CodeCoverageMixin, self).__init__()

    @property
    def code_coverage_enabled(self):
        try:
            if self.config.get('code_coverage'):
                return True

            # XXX workaround because bug 1110465 is hard
            return 'ccov' in self.buildbot_config['properties']['stage_platform']
        except (AttributeError, KeyError, TypeError):
            return False

    @property
    def per_test_coverage(self):
        try:
            return bool(self.config.get('per_test_coverage'))
        except (AttributeError, KeyError, TypeError):
            return False

    @property
    def ccov_upload_disabled(self):
        try:
            if self.config.get('disable_ccov_upload'):
                return True
            return False
        except (AttributeError, KeyError, TypeError):
            return False

    @property
    def jsd_code_coverage_enabled(self):
        try:
            if self.config.get('jsd_code_coverage'):
                return True

            # XXX workaround because bug 1110465 is hard
            return 'jsdcov' in self.buildbot_config['properties']['stage_platform']
        except (AttributeError, KeyError, TypeError):
            return False

    @PostScriptAction('download-and-extract')
    def setup_coverage_tools(self, action, success=None):
        if not self.code_coverage_enabled:
            return

        if mozinfo.os == 'linux':
            self.prefix = '/builds/worker/workspace/build/src/'
            strip_count = self.prefix.count('/')
        elif mozinfo.os == 'win':
            self.prefix = 'z:/build/build/src/'
            # Add 1 as on Windows the path where the compiler tries to write the
            # gcda files has an additional 'obj-firefox' component.
            strip_count = self.prefix.count('/') + 1

        os.environ['GCOV_PREFIX_STRIP'] = str(strip_count)

        # Install grcov on the test machine
        # Get the path to the build machines gcno files.
        self.url_to_gcno = self.query_build_dir_url('target.code-coverage-gcno.zip')
        self.url_to_chrome_map = self.query_build_dir_url('chrome-map.json')
        dirs = self.query_abs_dirs()

        # Create the grcov directory, get the tooltool manifest, and finally
        # download and unpack the grcov binary.
        self.grcov_dir = tempfile.mkdtemp()

        if mozinfo.os == 'linux':
            platform = 'linux64'
            tar_file = 'grcov-linux-standalone-x86_64.tar.bz2'
        elif mozinfo.os == 'win':
            platform = 'win32'
            tar_file = 'grcov-win-i686.tar.bz2'

        manifest = os.path.join(dirs.get('abs_test_install_dir', os.path.join(dirs['abs_work_dir'], 'tests')), \
            'config/tooltool-manifests/%s/ccov.manifest' % platform)

        cmd = [sys.executable, _tooltool_path, '--url', 'https://tooltool.mozilla-releng.net/', 'fetch', \
            '-m', manifest, '-o', '-c', '/builds/worker/tooltool-cache']
        self.run_command(cmd, cwd=self.grcov_dir)

        with tarfile.open(os.path.join(self.grcov_dir, tar_file)) as tar:
            tar.extractall(self.grcov_dir)

        # Download the gcno archive from the build machine.
        self.download_file(self.url_to_gcno, parent_dir=self.grcov_dir)

        # Download the chrome-map.json file from the build machine.
        self.download_file(self.url_to_chrome_map, parent_dir=self.grcov_dir)

    @PostScriptAction('download-and-extract')
    def find_tests_for_coverage(self, action, success=None):
        """
           For each file modified on this push, determine if the modified file
           is a test, by searching test manifests. Populate self.verify_suites
           with test files, organized by suite.

           This depends on test manifests, so can only run after test zips have
           been downloaded and extracted.
        """
        if not self.per_test_coverage:
            return

        self.find_modified_tests()
        # TODO: Add tests that haven't been run for a while (a week? N pushes?)

    @property
    def coverage_args(self):
        return []

    def set_coverage_env(self, env):
        # Set the GCOV directory.
        gcov_dir = tempfile.mkdtemp()
        env['GCOV_PREFIX'] = gcov_dir

        # Set JSVM directory.
        jsvm_dir = tempfile.mkdtemp()
        env['JS_CODE_COVERAGE_OUTPUT_DIR'] = jsvm_dir

        return (gcov_dir, jsvm_dir)

    @PreScriptAction('run-tests')
    def _set_gcov_prefix(self, action):
        if not self.code_coverage_enabled:
            return

        if self.per_test_coverage:
            return

        self.gcov_dir, self.jsvm_dir = self.set_coverage_env(os.environ)

    def parse_coverage_artifacts(self, gcov_dir, jsvm_dir, merge=False, output_format='lcov'):
        jsvm_output_file = 'jsvm_lcov_output.info'
        grcov_output_file = 'grcov_lcov_output.info'

        dirs = self.query_abs_dirs()

        sys.path.append(dirs['abs_test_install_dir'])
        sys.path.append(os.path.join(dirs['abs_test_install_dir'], 'mozbuild/codecoverage'))

        from lcov_rewriter import LcovFileRewriter
        jsvm_files = [os.path.join(jsvm_dir, e) for e in os.listdir(jsvm_dir)]
        rewriter = LcovFileRewriter(os.path.join(self.grcov_dir, 'chrome-map.json'))
        rewriter.rewrite_files(jsvm_files, jsvm_output_file, '')

        # Zip gcda files (will be given in input to grcov).
        file_path_gcda = os.path.join(os.getcwd(), 'code-coverage-gcda.zip')
        with zipfile.ZipFile(file_path_gcda, 'w', zipfile.ZIP_STORED) as z:
            for topdir, _, files in os.walk(gcov_dir):
                for f in files:
                    full_path = os.path.join(topdir, f)
                    rel_path = os.path.relpath(full_path, gcov_dir)
                    z.write(full_path, rel_path)

        # Run grcov on the zipped .gcno and .gcda files.
        grcov_command = [
            os.path.join(self.grcov_dir, 'grcov'),
            '-t', output_format,
            '-p', self.prefix,
            '--ignore-dir', 'gcc*',
            '--ignore-dir', 'vs2017_*',
            os.path.join(self.grcov_dir, 'target.code-coverage-gcno.zip'), file_path_gcda
        ]

        if 'coveralls' in output_format:
            grcov_command += ['--token', 'UNUSED', '--commit-sha', 'UNUSED']

        if merge:
            grcov_command += [jsvm_output_file]

        if mozinfo.os == 'win':
            grcov_command += ['--llvm']

        # 'grcov_output' will be a tuple, the first variable is the path to the lcov output,
        # the other is the path to the standard error output.
        tmp_output_file, _ = self.get_output_from_command(
            grcov_command,
            silent=True,
            save_tmpfiles=True,
            return_type='files',
            throw_exception=True,
        )
        shutil.move(tmp_output_file, grcov_output_file)

        shutil.rmtree(gcov_dir)
        shutil.rmtree(jsvm_dir)

        if merge:
            os.remove(jsvm_output_file)
            return grcov_output_file
        else:
            return grcov_output_file, jsvm_output_file

    def add_per_test_coverage_report(self, gcov_dir, jsvm_dir, suite, test):
        grcov_file = self.parse_coverage_artifacts(
            gcov_dir, jsvm_dir, merge=True, output_format='coveralls'
        )

        report_file = str(uuid.uuid4()) + '.json'
        shutil.move(grcov_file, report_file)

        if suite not in self.per_test_reports:
            self.per_test_reports[suite] = {}
        assert test not in self.per_test_reports[suite]
        self.per_test_reports[suite][test] = report_file

    @PostScriptAction('run-tests')
    def _package_coverage_data(self, action, success=None):
        dirs = self.query_abs_dirs()

        if self.jsd_code_coverage_enabled:
            # Setup the command for compression
            jsdcov_dir = dirs['abs_blob_upload_dir']
            zipFile = os.path.join(jsdcov_dir, "jsdcov_artifacts.zip")

            self.info("Beginning compression of JSDCov artifacts...")
            with zipfile.ZipFile(zipFile, 'w', zipfile.ZIP_DEFLATED) as z:
                for filename in os.listdir(jsdcov_dir):
                    if filename.startswith("jscov") and filename.endswith(".json"):
                        path = os.path.join(jsdcov_dir, filename)
                        z.write(path, filename)
                        # Delete already compressed JSCov artifacts.
                        os.remove(path)

            self.info("Completed compression of JSDCov artifacts!")
            self.info("Path to JSDCov compressed artifacts: " + zipFile)

        if not self.code_coverage_enabled:
            return

        if self.per_test_coverage:
            if not self.per_test_reports:
                self.info("No tests were found...not saving coverage data.")
                return

            dest = os.path.join(dirs['abs_blob_upload_dir'], 'per-test-coverage-reports.zip')
            with zipfile.ZipFile(dest, 'w', zipfile.ZIP_DEFLATED) as z:
                for suite, data in self.per_test_reports.items():
                    for test, grcov_file in data.items():
                        with open(grcov_file, 'r') as f:
                            report = json.load(f)

                        # TODO: Diff this coverage report with the baseline one.

                        with open(grcov_file, 'w') as f:
                            json.dump({
                                'test': test,
                                'suite': suite,
                                'report': report,
                            }, f)

                        z.write(grcov_file)
            return

        del os.environ['GCOV_PREFIX_STRIP']
        del os.environ['GCOV_PREFIX']
        del os.environ['JS_CODE_COVERAGE_OUTPUT_DIR']

        if not self.ccov_upload_disabled:
            grcov_output_file, jsvm_output_file = self.parse_coverage_artifacts(self.gcov_dir, self.jsvm_dir)

            # Zip the grcov output and upload it.
            grcov_zip_path = os.path.join(dirs['abs_blob_upload_dir'], 'code-coverage-grcov.zip')
            with zipfile.ZipFile(grcov_zip_path, 'w', zipfile.ZIP_DEFLATED) as z:
                z.write(grcov_output_file)

            # Zip the JSVM coverage data and upload it.
            jsvm_zip_path = os.path.join(dirs['abs_blob_upload_dir'], 'code-coverage-jsvm.zip')
            with zipfile.ZipFile(jsvm_zip_path, 'w', zipfile.ZIP_DEFLATED) as z:
                z.write(jsvm_output_file)

        shutil.rmtree(self.grcov_dir)
