#!/usr/bin/env python3
# group: rw quick
# Exercize QEMU generated ACPI/SMBIOS tables using biosbits,
# https://biosbits.org/
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
#
# Author:
#  Ani Sinha <ani@anisinha.ca>

# pylint: disable=invalid-name
# pylint: disable=consider-using-f-string

"""
This is QEMU ACPI/SMBIOS avocado tests using biosbits.
Biosbits is available originally at https://biosbits.org/.
This test uses a fork of the upstream bits and has numerous fixes
including an upgraded acpica. The fork is located here:
https://gitlab.com/qemu-project/biosbits-bits .
"""

import logging
import os
import platform
import re
import shutil
import subprocess
import tarfile
import tempfile
import time
import zipfile
from typing import (
    List,
    Optional,
    Sequence,
)
from qemu.machine import QEMUMachine
from avocado import skipIf
from avocado_qemu import QemuBaseTest

deps = ["xorriso", "mformat"] # dependent tools needed in the test setup/box.
supported_platforms = ['x86_64'] # supported test platforms.


def which(tool):
    """ looks up the full path for @tool, returns None if not found
        or if @tool does not have executable permissions.
    """
    paths=os.getenv('PATH')
    for p in paths.split(os.path.pathsep):
        p = os.path.join(p, tool)
        if os.path.exists(p) and os.access(p, os.X_OK):
            return p
    return None

def missing_deps():
    """ returns True if any of the test dependent tools are absent.
    """
    for dep in deps:
        if which(dep) is None:
            return True
    return False

def supported_platform():
    """ checks if the test is running on a supported platform.
    """
    return platform.machine() in supported_platforms

class QEMUBitsMachine(QEMUMachine): # pylint: disable=too-few-public-methods
    """
    A QEMU VM, with isa-debugcon enabled and bits iso passed
    using -cdrom to QEMU commandline.

    """
    def __init__(self,
                 binary: str,
                 args: Sequence[str] = (),
                 wrapper: Sequence[str] = (),
                 name: Optional[str] = None,
                 base_temp_dir: str = "/var/tmp",
                 debugcon_log: str = "debugcon-log.txt",
                 debugcon_addr: str = "0x403",
                 sock_dir: Optional[str] = None,
                 qmp_timer: Optional[float] = None):
        # pylint: disable=too-many-arguments

        if name is None:
            name = "qemu-bits-%d" % os.getpid()
        if sock_dir is None:
            sock_dir = base_temp_dir
        super().__init__(binary, args, wrapper=wrapper, name=name,
                         base_temp_dir=base_temp_dir,
                         sock_dir=sock_dir, qmp_timer=qmp_timer)
        self.debugcon_log = debugcon_log
        self.debugcon_addr = debugcon_addr
        self.base_temp_dir = base_temp_dir

    @property
    def _base_args(self) -> List[str]:
        args = super()._base_args
        args.extend([
            '-chardev',
            'file,path=%s,id=debugcon' %os.path.join(self.base_temp_dir,
                                                     self.debugcon_log),
            '-device',
            'isa-debugcon,iobase=%s,chardev=debugcon' %self.debugcon_addr,
        ])
        return args

    def base_args(self):
        """return the base argument to QEMU binary"""
        return self._base_args

@skipIf(not supported_platform() or missing_deps(),
        'unsupported platform or dependencies (%s) not installed' \
        % ','.join(deps))
class AcpiBitsTest(QemuBaseTest): #pylint: disable=too-many-instance-attributes
    """
    ACPI and SMBIOS tests using biosbits.

    :avocado: tags=arch:x86_64
    :avocado: tags=acpi

    """
    # in slower systems the test can take as long as 3 minutes to complete.
    timeout = 200

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self._vm = None
        self._workDir = None
        self._baseDir = None

        # following are some standard configuration constants
        self._bitsInternalVer = 2020
        self._bitsCommitHash = 'b48b88ff' # commit hash must match
                                          # the artifact tag below
        self._bitsTag = "qemu-bits-10182022" # this is the latest bits
                                             # release as of today.
        self._bitsArtSHA1Hash = 'b04790ac9b99b5662d0416392c73b97580641fe5'
        self._bitsArtURL = ("https://gitlab.com/qemu-project/"
                            "biosbits-bits/-/jobs/artifacts/%s/"
                            "download?job=qemu-bits-build" %self._bitsTag)
        self._debugcon_addr = '0x403'
        self._debugcon_log = 'debugcon-log.txt'
        logging.basicConfig(level=logging.INFO)
        self.logger = logging.getLogger('acpi-bits')

    def _print_log(self, log):
        self.logger.info('\nlogs from biosbits follows:')
        self.logger.info('==========================================\n')
        self.logger.info(log)
        self.logger.info('==========================================\n')

    def copy_bits_config(self):
        """ copies the bios bits config file into bits.
        """
        config_file = 'bits-cfg.txt'
        bits_config_dir = os.path.join(self._baseDir, 'acpi-bits',
                                       'bits-config')
        target_config_dir = os.path.join(self._workDir,
                                         'bits-%d' %self._bitsInternalVer,
                                         'boot')
        self.assertTrue(os.path.exists(bits_config_dir))
        self.assertTrue(os.path.exists(target_config_dir))
        self.assertTrue(os.access(os.path.join(bits_config_dir,
                                               config_file), os.R_OK))
        shutil.copy2(os.path.join(bits_config_dir, config_file),
                     target_config_dir)
        self.logger.info('copied config file %s to %s',
                         config_file, target_config_dir)

    def copy_test_scripts(self):
        """copies the python test scripts into bits. """

        bits_test_dir = os.path.join(self._baseDir, 'acpi-bits',
                                     'bits-tests')
        target_test_dir = os.path.join(self._workDir,
                                       'bits-%d' %self._bitsInternalVer,
                                       'boot', 'python')

        self.assertTrue(os.path.exists(bits_test_dir))
        self.assertTrue(os.path.exists(target_test_dir))

        for filename in os.listdir(bits_test_dir):
            if os.path.isfile(os.path.join(bits_test_dir, filename)) and \
               filename.endswith('.py2'):
                # all test scripts are named with extension .py2 so that
                # avocado does not try to load them. These scripts are
                # written for python 2.7 not python 3 and hence if avocado
                # loaded them, it would complain about python 3 specific
                # syntaxes.
                newfilename = os.path.splitext(filename)[0] + '.py'
                shutil.copy2(os.path.join(bits_test_dir, filename),
                             os.path.join(target_test_dir, newfilename))
                self.logger.info('copied test file %s to %s',
                                 filename, target_test_dir)

                # now remove the pyc test file if it exists, otherwise the
                # changes in the python test script won't be executed.
                testfile_pyc = os.path.splitext(filename)[0] + '.pyc'
                if os.access(os.path.join(target_test_dir, testfile_pyc),
                             os.F_OK):
                    os.remove(os.path.join(target_test_dir, testfile_pyc))
                    self.logger.info('removed compiled file %s',
                                     os.path.join(target_test_dir,
                                     testfile_pyc))

    def fix_mkrescue(self, mkrescue):
        """ grub-mkrescue is a bash script with two variables, 'prefix' and
            'libdir'. They must be pointed to the right location so that the
            iso can be generated appropriately. We point the two variables to
            the directory where we have extracted our pre-built bits grub
            tarball.
        """
        grub_x86_64_mods = os.path.join(self._workDir, 'grub-inst-x86_64-efi')
        grub_i386_mods = os.path.join(self._workDir, 'grub-inst')

        self.assertTrue(os.path.exists(grub_x86_64_mods))
        self.assertTrue(os.path.exists(grub_i386_mods))

        new_script = ""
        with open(mkrescue, 'r', encoding='utf-8') as filehandle:
            orig_script = filehandle.read()
            new_script = re.sub('(^prefix=)(.*)',
                                r'\1"%s"' %grub_x86_64_mods,
                                orig_script, flags=re.M)
            new_script = re.sub('(^libdir=)(.*)', r'\1"%s/lib"' %grub_i386_mods,
                                new_script, flags=re.M)

        with open(mkrescue, 'w', encoding='utf-8') as filehandle:
            filehandle.write(new_script)

    def generate_bits_iso(self):
        """ Uses grub-mkrescue to generate a fresh bits iso with the python
            test scripts
        """
        bits_dir = os.path.join(self._workDir,
                                'bits-%d' %self._bitsInternalVer)
        iso_file = os.path.join(self._workDir,
                                'bits-%d.iso' %self._bitsInternalVer)
        mkrescue_script = os.path.join(self._workDir,
                                       'grub-inst-x86_64-efi', 'bin',
                                       'grub-mkrescue')

        self.assertTrue(os.access(mkrescue_script,
                                  os.R_OK | os.W_OK | os.X_OK))

        self.fix_mkrescue(mkrescue_script)

        self.logger.info('using grub-mkrescue for generating biosbits iso ...')

        try:
            if os.getenv('V') or os.getenv('BITS_DEBUG'):
                subprocess.check_call([mkrescue_script, '-o', iso_file,
                                       bits_dir], stderr=subprocess.STDOUT)
            else:
                subprocess.check_call([mkrescue_script, '-o',
                                      iso_file, bits_dir],
                                      stderr=subprocess.DEVNULL,
                                      stdout=subprocess.DEVNULL)
        except Exception as e: # pylint: disable=broad-except
            self.skipTest("Error while generating the bits iso. "
                          "Pass V=1 in the environment to get more details. "
                          + str(e))

        self.assertTrue(os.access(iso_file, os.R_OK))

        self.logger.info('iso file %s successfully generated.', iso_file)

    def setUp(self): # pylint: disable=arguments-differ
        super().setUp('qemu-system-')

        self._baseDir = os.getenv('AVOCADO_TEST_BASEDIR')

        # workdir could also be avocado's own workdir in self.workdir.
        # At present, I prefer to maintain my own temporary working
        # directory. It gives us more control over the generated bits
        # log files and also for debugging, we may chose not to remove
        # this working directory so that the logs and iso can be
        # inspected manually and archived if needed.
        self._workDir = tempfile.mkdtemp(prefix='acpi-bits-',
                                         suffix='.tmp')
        self.logger.info('working dir: %s', self._workDir)

        prebuiltDir = os.path.join(self._workDir, 'prebuilt')
        if not os.path.isdir(prebuiltDir):
            os.mkdir(prebuiltDir, mode=0o775)

        bits_zip_file = os.path.join(prebuiltDir, 'bits-%d-%s.zip'
                                     %(self._bitsInternalVer,
                                       self._bitsCommitHash))
        grub_tar_file = os.path.join(prebuiltDir,
                                     'bits-%d-%s-grub.tar.gz'
                                     %(self._bitsInternalVer,
                                       self._bitsCommitHash))

        bitsLocalArtLoc = self.fetch_asset(self._bitsArtURL,
                                           asset_hash=self._bitsArtSHA1Hash)
        self.logger.info("downloaded bits artifacts to %s", bitsLocalArtLoc)

        # extract the bits artifact in the temp working directory
        with zipfile.ZipFile(bitsLocalArtLoc, 'r') as zref:
            zref.extractall(prebuiltDir)

        # extract the bits software in the temp working directory
        with zipfile.ZipFile(bits_zip_file, 'r') as zref:
            zref.extractall(self._workDir)

        with tarfile.open(grub_tar_file, 'r', encoding='utf-8') as tarball:
            tarball.extractall(self._workDir)

        self.copy_test_scripts()
        self.copy_bits_config()
        self.generate_bits_iso()

    def parse_log(self):
        """parse the log generated by running bits tests and
           check for failures.
        """
        debugconf = os.path.join(self._workDir, self._debugcon_log)
        log = ""
        with open(debugconf, 'r', encoding='utf-8') as filehandle:
            log = filehandle.read()

        matchiter = re.finditer(r'(.*Summary: )(\d+ passed), (\d+ failed).*',
                                log)
        for match in matchiter:
            # verify that no test cases failed.
            try:
                self.assertEqual(match.group(3).split()[0], '0',
                                 'Some bits tests seems to have failed. ' \
                                 'Please check the test logs for more info.')
            except AssertionError as e:
                self._print_log(log)
                raise e
            else:
                if os.getenv('V') or os.getenv('BITS_DEBUG'):
                    self._print_log(log)

    def tearDown(self):
        """
           Lets do some cleanups.
        """
        if self._vm:
            self.assertFalse(not self._vm.is_running)
        if not os.getenv('BITS_DEBUG') and self._workDir:
            self.logger.info('removing the work directory %s', self._workDir)
            shutil.rmtree(self._workDir)
        else:
            self.logger.info('not removing the work directory %s ' \
                             'as BITS_DEBUG is ' \
                             'passed in the environment', self._workDir)
        super().tearDown()

    def test_acpi_smbios_bits(self):
        """The main test case implementaion."""

        iso_file = os.path.join(self._workDir,
                                'bits-%d.iso' %self._bitsInternalVer)

        self.assertTrue(os.access(iso_file, os.R_OK))

        self._vm = QEMUBitsMachine(binary=self.qemu_bin,
                                   base_temp_dir=self._workDir,
                                   debugcon_log=self._debugcon_log,
                                   debugcon_addr=self._debugcon_addr)

        self._vm.add_args('-cdrom', '%s' %iso_file)
        # the vm needs to be run under icount so that TCG emulation is
        # consistent in terms of timing. smilatency tests have consistent
        # timing requirements.
        self._vm.add_args('-icount', 'auto')

        args = " ".join(str(arg) for arg in self._vm.base_args()) + \
            " " + " ".join(str(arg) for arg in self._vm.args)

        self.logger.info("launching QEMU vm with the following arguments: %s",
                         args)

        self._vm.launch()
        # biosbits has been configured to run all the specified test suites
        # in batch mode and then automatically initiate a vm shutdown.
        # Rely on avocado's unit test timeout.
        self._vm.wait(timeout=None)
        self.parse_log()