# Please keep this code python 2.4 compatible and stand alone.

import logging, os, shutil, sys, tempfile, time, urllib2
import subprocess, re
from autotest_lib.client.common_lib import utils

_READ_SIZE = 64*1024
_MAX_PACKAGE_SIZE = 100*1024*1024


class Error(Exception):
    """Local exception to be raised by code in this file."""

class FetchError(Error):
    """Failed to fetch a package from any of its listed URLs."""


def _checksum_file(full_path):
    """@returns The hex checksum of a file given its pathname."""
    inputfile = open(full_path, 'rb')
    try:
        hex_sum = utils.hash('sha1', inputfile.read()).hexdigest()
    finally:
        inputfile.close()
    return hex_sum


def system(commandline):
    """Same as os.system(commandline) but logs the command first."""
    logging.info(commandline)
    return os.system(commandline)


def find_top_of_autotest_tree():
    """@returns The full path to the top of the autotest directory tree."""
    dirname = os.path.dirname(__file__)
    autotest_dir = os.path.abspath(os.path.join(dirname, '..'))
    return autotest_dir


class ExternalPackage(object):
    """
    Defines an external package with URLs to fetch its sources from and
    a build_and_install() method to unpack it, build it and install it
    beneath our own autotest/site-packages directory.

    Base Class.  Subclass this to define packages.

    Attributes:
      @attribute urls - A tuple of URLs to try fetching the package from.
      @attribute local_filename - A local filename to use when saving the
              fetched package.
      @attribute hex_sum - The hex digest (currently SHA1) of this package
              to be used to verify its contents.
      @attribute module_name - The installed python module name to be used for
              for a version check.  Defaults to the lower case class name with
              the word Package stripped off.
      @attribute version - The desired minimum package version.
      @attribute os_requirements - A dictionary mapping a file pathname on the
              the OS distribution to a likely name of a package the user
              needs to install on their system in order to get this file.
      @attribute name - Read only, the printable name of the package.
      @attribute subclasses - This class attribute holds a list of all defined
              subclasses.  It is constructed dynamically using the metaclass.
    """
    subclasses = []
    urls = ()
    local_filename = None
    hex_sum = None
    module_name = None
    version = None
    os_requirements = None


    class __metaclass__(type):
        """Any time a subclass is defined, add it to our list."""
        def __init__(mcs, name, bases, dict):
            if name != 'ExternalPackage':
                mcs.subclasses.append(mcs)


    def __init__(self):
        self.verified_package = ''
        if not self.module_name:
            self.module_name = self.name.lower()
        self.installed_version = ''


    @property
    def name(self):
        """Return the class name with any trailing 'Package' stripped off."""
        class_name = self.__class__.__name__
        if class_name.endswith('Package'):
            return class_name[:-len('Package')]
        return class_name


    def is_needed(self, unused_install_dir):
        """@returns True if self.module_name needs to be built and installed."""
        if not self.module_name or not self.version:
            logging.warning('version and module_name required for '
                            'is_needed() check to work.')
            return True
        try:
            module = __import__(self.module_name)
        except ImportError, e:
            logging.info("%s isn't present. Will install.", self.module_name)
            return True
        self.installed_version = self._get_installed_version_from_module(module)
        logging.info('imported %s version %s.', self.module_name,
                     self.installed_version)
        if hasattr(self, 'minimum_version'):
            return self.minimum_version > self.installed_version
        else:
            return self.version > self.installed_version


    def _get_installed_version_from_module(self, module):
        """Ask our module its version string and return it or '' if unknown."""
        try:
            return module.__version__
        except AttributeError:
            logging.error('could not get version from %s', module)
            return ''


    def _build_and_install(self, install_dir):
        """Subclasses MUST provide their own implementation."""
        raise NotImplementedError


    def _build_and_install_current_dir(self, install_dir):
        """
        Subclasses that use _build_and_install_from_package() MUST provide
        their own implementation of this method.
        """
        raise NotImplementedError


    def build_and_install(self, install_dir):
        """
        Builds and installs the package.  It must have been fetched already.

        @param install_dir - The package installation directory.  If it does
            not exist it will be created.
        """
        if not self.verified_package:
            raise Error('Must call fetch() first.  - %s' % self.name)
        self._check_os_requirements()
        return self._build_and_install(install_dir)


    def _check_os_requirements(self):
        if not self.os_requirements:
            return
        failed = False
        for file_name, package_name in self.os_requirements.iteritems():
            if not os.path.exists(file_name):
                failed = True
                logging.error('File %s not found, %s needs it.',
                              file_name, self.name)
                logging.error('Perhaps you need to install something similar '
                              'to the %s package for OS first.', package_name)
        if failed:
            raise Error('Missing OS requirements for %s.  (see above)' %
                        self.name)


    def _build_and_install_current_dir_setup_py(self, install_dir):
        """For use as a _build_and_install_current_dir implementation."""
        egg_path = self._build_egg_using_setup_py(setup_py='setup.py')
        if not egg_path:
            return False
        return self._install_from_egg(install_dir, egg_path)


    def _build_and_install_current_dir_setupegg_py(self, install_dir):
        """For use as a _build_and_install_current_dir implementation."""
        egg_path = self._build_egg_using_setup_py(setup_py='setupegg.py')
        if not egg_path:
            return False
        return self._install_from_egg(install_dir, egg_path)


    def _build_and_install_current_dir_noegg(self, install_dir):
        if not self._build_using_setup_py():
            return False
        return self._install_using_setup_py_and_rsync(install_dir)


    def _build_and_install_from_package(self, install_dir):
        """
        This method may be used as a _build_and_install() implementation
        for subclasses if they implement _build_and_install_current_dir().

        Extracts the .tar.gz file, chdirs into the extracted directory
        (which is assumed to match the tar filename) and calls
        _build_and_isntall_current_dir from there.

        Afterwards the build (regardless of failure) extracted .tar.gz
        directory is cleaned up.

        @returns True on success, False otherwise.

        @raises OSError If the expected extraction directory does not exist.
        """
        self._extract_compressed_package()
        if self.verified_package.endswith('.tar.gz'):
            extension = '.tar.gz'
        elif self.verified_package.endswith('.tar.bz2'):
            extension = '.tar.bz2'
        elif self.verified_package.endswith('.zip'):
            extension = '.zip'
        else:
            raise Error('Unexpected package file extension on %s' %
                        self.verified_package)
        os.chdir(os.path.dirname(self.verified_package))
        os.chdir(self.local_filename[:-len(extension)])
        extracted_dir = os.getcwd()
        try:
            return self._build_and_install_current_dir(install_dir)
        finally:
            os.chdir(os.path.join(extracted_dir, '..'))
            shutil.rmtree(extracted_dir)


    def _extract_compressed_package(self):
        """Extract the fetched compressed .tar or .zip within its directory."""
        if not self.verified_package:
            raise Error('Package must have been fetched first.')
        os.chdir(os.path.dirname(self.verified_package))
        if self.verified_package.endswith('gz'):
            status = system("tar -xzf '%s'" % self.verified_package)
        elif self.verified_package.endswith('bz2'):
            status = system("tar -xjf '%s'" % self.verified_package)
        elif self.verified_package.endswith('zip'):
            status = system("unzip '%s'" % self.verified_package)
        else:
            raise Error('Unknown compression suffix on %s.' %
                        self.verified_package)
        if status:
            raise Error('tar failed with %s' % (status,))


    def _build_using_setup_py(self, setup_py='setup.py'):
        """
        Assuming the cwd is the extracted python package, execute a simple
        python setup.py build.

        @param setup_py - The name of the setup.py file to execute.

        @returns True on success, False otherwise.
        """
        if not os.path.exists(setup_py):
            raise Error('%s does not exist in %s' % (setup_py, os.getcwd()))
        status = system("'%s' %s build" % (sys.executable, setup_py))
        if status:
            logging.error('%s build failed.' % self.name)
            return False
        return True


    def _build_egg_using_setup_py(self, setup_py='setup.py'):
        """
        Assuming the cwd is the extracted python package, execute a simple
        python setup.py bdist_egg.

        @param setup_py - The name of the setup.py file to execute.

        @returns The relative path to the resulting egg file or '' on failure.
        """
        if not os.path.exists(setup_py):
            raise Error('%s does not exist in %s' % (setup_py, os.getcwd()))
        egg_subdir = 'dist'
        if os.path.isdir(egg_subdir):
            shutil.rmtree(egg_subdir)
        status = system("'%s' %s bdist_egg" % (sys.executable, setup_py))
        if status:
            logging.error('bdist_egg of setuptools failed.')
            return ''
        # I've never seen a bdist_egg lay multiple .egg files.
        for filename in os.listdir(egg_subdir):
            if filename.endswith('.egg'):
                return os.path.join(egg_subdir, filename)


    def _install_from_egg(self, install_dir, egg_path):
        """
        Install a module from an egg file by unzipping the necessary parts
        into install_dir.

        @param install_dir - The installation directory.
        @param egg_path - The pathname of the egg file.
        """
        status = system("unzip -q -o -d '%s' '%s'" % (install_dir, egg_path))
        if status:
            logging.error('unzip of %s failed', egg_path)
            return False
        egg_info = os.path.join(install_dir, 'EGG-INFO')
        if os.path.isdir(egg_info):
            shutil.rmtree(egg_info)
        return True


    def _get_temp_dir(self):
        return tempfile.mkdtemp(dir='/var/tmp')


    def _site_packages_path(self, temp_dir):
        # This makes assumptions about what python setup.py install
        # does when given a prefix.  Is this always correct?
        python_xy = 'python%s' % sys.version[:3]
        return os.path.join(temp_dir, 'lib', python_xy, 'site-packages')


    def _install_using_setup_py_and_rsync(self, install_dir,
                                          setup_py='setup.py',
                                          temp_dir=None):
        """
        Assuming the cwd is the extracted python package, execute a simple:

          python setup.py install --prefix=BLA

        BLA will be a temporary directory that everything installed will
        be picked out of and rsynced to the appropriate place under
        install_dir afterwards.

        Afterwards, it deconstructs the extra lib/pythonX.Y/site-packages/
        directory tree that setuptools created and moves all installed
        site-packages directly up into install_dir itself.

        @param install_dir the directory for the install to happen under.
        @param setup_py - The name of the setup.py file to execute.

        @returns True on success, False otherwise.
        """
        if not os.path.exists(setup_py):
            raise Error('%s does not exist in %s' % (setup_py, os.getcwd()))

        if temp_dir is None:
            temp_dir = self._get_temp_dir()

        try:
            status = system("'%s' %s install --no-compile --prefix='%s'"
                            % (sys.executable, setup_py, temp_dir))
            if status:
                logging.error('%s install failed.' % self.name)
                return False

            if os.path.isdir(os.path.join(temp_dir, 'lib')):
                # NOTE: This ignores anything outside of the lib/ dir that
                # was installed.
                temp_site_dir = self._site_packages_path(temp_dir)
            else:
                temp_site_dir = temp_dir

            status = system("rsync -r '%s/' '%s/'" %
                            (temp_site_dir, install_dir))
            if status:
                logging.error('%s rsync to install_dir failed.' % self.name)
                return False
            return True
        finally:
            shutil.rmtree(temp_dir)


    def _build_using_make(self, install_dir):
        """Build the current package using configure/make.

        @returns True on success, False otherwise.
        """
        install_prefix = os.path.join(install_dir, 'usr', 'local')
        status = system('./configure --prefix=%s' % install_prefix)
        if status:
            logging.error('./configure failed for %s', self.name)
            return False
        status = system('make')
        if status:
            logging.error('make failed for %s', self.name)
            return False
        status = system('make check')
        if status:
            logging.error('make check failed for %s', self.name)
            return False
        return True


    def _install_using_make(self):
        """Install the current package using make install.

        Assumes the install path was set up while running ./configure (in
        _build_using_make()).

        @returns True on success, False otherwise.
        """
        status = system('make install')
        return status == 0


    def fetch(self, dest_dir):
        """
        Fetch the package from one its URLs and save it in dest_dir.

        If the the package already exists in dest_dir and the checksum
        matches this code will not fetch it again.

        Sets the 'verified_package' attribute with the destination pathname.

        @param dest_dir - The destination directory to save the local file.
            If it does not exist it will be created.

        @returns A boolean indicating if we the package is now in dest_dir.
        @raises FetchError - When something unexpected happens.
        """
        if not os.path.exists(dest_dir):
            os.makedirs(dest_dir)
        local_path = os.path.join(dest_dir, self.local_filename)

        # If the package exists, verify its checksum and be happy if it is good.
        if os.path.exists(local_path):
            actual_hex_sum = _checksum_file(local_path)
            if self.hex_sum == actual_hex_sum:
                logging.info('Good checksum for existing %s package.',
                             self.name)
                self.verified_package = local_path
                return True
            logging.warning('Bad checksum for existing %s package.  '
                            'Re-downloading', self.name)
            os.rename(local_path, local_path + '.wrong-checksum')

        # Download the package from one of its urls, rejecting any if the
        # checksum does not match.
        for url in self.urls:
            logging.info('Fetching %s', url)
            try:
                url_file = urllib2.urlopen(url)
            except (urllib2.URLError, EnvironmentError):
                logging.warning('Could not fetch %s package from %s.',
                                self.name, url)
                continue
            data_length = int(url_file.info().get('Content-Length',
                                                  _MAX_PACKAGE_SIZE))
            if data_length <= 0 or data_length > _MAX_PACKAGE_SIZE:
                raise FetchError('%s from %s fails Content-Length %d '
                                 'sanity check.' % (self.name, url,
                                                    data_length))
            checksum = utils.hash('sha1')
            total_read = 0
            output = open(local_path, 'wb')
            try:
                while total_read < data_length:
                    data = url_file.read(_READ_SIZE)
                    if not data:
                        break
                    output.write(data)
                    checksum.update(data)
                    total_read += len(data)
            finally:
                output.close()
            if self.hex_sum != checksum.hexdigest():
                logging.warning('Bad checksum for %s fetched from %s.',
                                self.name, url)
                logging.warning('Got %s', checksum.hexdigest())
                logging.warning('Expected %s', self.hex_sum)
                os.unlink(local_path)
                continue
            logging.info('Good checksum.')
            self.verified_package = local_path
            return True
        else:
            return False


# NOTE: This class definition must come -before- all other ExternalPackage
# classes that need to use this version of setuptools so that is is inserted
# into the ExternalPackage.subclasses list before them.
class SetuptoolsPackage(ExternalPackage):
    # For all known setuptools releases a string compare works for the
    # version string.  Hopefully they never release a 0.10.  (Their own
    # version comparison code would break if they did.)
    # Any system with setuptools > 0.6 is fine. If none installed, then
    # try to install the latest found on the upstream.
    minimum_version = '0.6'
    version = '0.6c11'
    urls = ('http://pypi.python.org/packages/source/s/setuptools/'
            'setuptools-%s.tar.gz' % (version,),)
    local_filename = 'setuptools-%s.tar.gz' % version
    hex_sum = '8d1ad6384d358c547c50c60f1bfdb3362c6c4a7d'

    SUDO_SLEEP_DELAY = 15


    def _build_and_install(self, install_dir):
        """Install setuptools on the system."""
        logging.info('NOTE: setuptools install does not use install_dir.')
        return self._build_and_install_from_package(install_dir)


    def _build_and_install_current_dir(self, install_dir):
        egg_path = self._build_egg_using_setup_py()
        if not egg_path:
            return False

        print '!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!\n'
        print 'About to run sudo to install setuptools', self.version
        print 'on your system for use by', sys.executable, '\n'
        print '!! ^C within', self.SUDO_SLEEP_DELAY, 'seconds to abort.\n'
        time.sleep(self.SUDO_SLEEP_DELAY)

        # Copy the egg to the local filesystem /var/tmp so that root can
        # access it properly (avoid NFS squashroot issues).
        temp_dir = self._get_temp_dir()
        try:
            shutil.copy(egg_path, temp_dir)
            egg_name = os.path.split(egg_path)[1]
            temp_egg = os.path.join(temp_dir, egg_name)
            p = subprocess.Popen(['sudo', '/bin/sh', temp_egg],
                                 stdout=subprocess.PIPE)
            regex = re.compile('Copying (.*?) to (.*?)\n')
            match = regex.search(p.communicate()[0])
            status = p.wait()

            if match:
                compiled = os.path.join(match.group(2), match.group(1))
                os.system("sudo chmod a+r '%s'" % compiled)
        finally:
            shutil.rmtree(temp_dir)

        if status:
            logging.error('install of setuptools from egg failed.')
            return False
        return True


class MySQLdbPackage(ExternalPackage):
    module_name = 'MySQLdb'
    version = '1.2.2'
    urls = ('http://downloads.sourceforge.net/project/mysql-python/'
            'mysql-python/%(version)s/MySQL-python-%(version)s.tar.gz'
            % dict(version=version),)
    local_filename = 'MySQL-python-%s.tar.gz' % version
    hex_sum = '945a04773f30091ad81743f9eb0329a3ee3de383'

    _build_and_install_current_dir = (
            ExternalPackage._build_and_install_current_dir_setup_py)


    def _build_and_install(self, install_dir):
        if not os.path.exists('/usr/bin/mysql_config'):
            logging.error('You need to install /usr/bin/mysql_config')
            logging.error('On Ubuntu or Debian based systems use this: '
                          'sudo apt-get install libmysqlclient15-dev')
            return False
        return self._build_and_install_from_package(install_dir)


class DjangoPackage(ExternalPackage):
    version = '1.3'
    local_filename = 'Django-%s.tar.gz' % version
    urls = ('http://www.djangoproject.com/download/%s/tarball/' % version,)
    hex_sum = 'f8814d5e1412bb932318db5130260da5bf053ff7'

    _build_and_install = ExternalPackage._build_and_install_from_package
    _build_and_install_current_dir = (
            ExternalPackage._build_and_install_current_dir_noegg)


    def _get_installed_version_from_module(self, module):
        try:
            return module.get_version().split()[0]
        except AttributeError:
            return '0.9.6'


class NumpyPackage(ExternalPackage):
    version = '1.2.1'
    local_filename = 'numpy-%s.tar.gz' % version
    urls = ('http://downloads.sourceforge.net/project/numpy/NumPy/%(version)s/'
            'numpy-%(version)s.tar.gz' % dict(version=version),)
    hex_sum = '1aa706e733aea18eaffa70d93c0105718acb66c5'

    _build_and_install = ExternalPackage._build_and_install_from_package
    _build_and_install_current_dir = (
            ExternalPackage._build_and_install_current_dir_setupegg_py)


# This requires numpy so it must be declared after numpy to guarantee that it
# is already installed.
class MatplotlibPackage(ExternalPackage):
    version = '0.98.5.3'
    short_version = '0.98.5'
    local_filename = 'matplotlib-%s.tar.gz' % version
    urls = ('http://downloads.sourceforge.net/project/matplotlib/matplotlib/'
            'matplotlib-%s/matplotlib-%s.tar.gz' % (short_version, version),)
    hex_sum = '2f6c894cf407192b3b60351bcc6468c0385d47b6'
    os_requirements = {'/usr/include/ft2build.h': 'libfreetype6-dev',
                       '/usr/include/png.h': 'libpng12-dev'}

    _build_and_install = ExternalPackage._build_and_install_from_package
    _build_and_install_current_dir = (
            ExternalPackage._build_and_install_current_dir_setupegg_py)


class AtForkPackage(ExternalPackage):
    version = '0.1.2'
    local_filename = 'atfork-%s.zip' % version
    urls = ('http://python-atfork.googlecode.com/files/' + local_filename,)
    hex_sum = '5baa64c73e966b57fa797040585c760c502dc70b'

    _build_and_install = ExternalPackage._build_and_install_from_package
    _build_and_install_current_dir = (
            ExternalPackage._build_and_install_current_dir_noegg)


class ParamikoPackage(ExternalPackage):
    version = '1.7.5'
    local_filename = 'paramiko-%s.tar.gz' % version
    urls = ('http://www.lag.net/paramiko/download/' + local_filename,
            'ftp://mirrors.kernel.org/gentoo/distfiles/' + local_filename,)
    hex_sum = '592be7a08290070b71da63a8e6f28a803399e5c5'


    _build_and_install = ExternalPackage._build_and_install_from_package


    def _check_for_pycrypto(self):
        # NOTE(gps): Linux distros have better python-crypto packages than we
        # can easily get today via a wget due to the library's age and staleness
        # yet many security and behavior bugs are fixed by patches that distros
        # already apply.  PyCrypto has a new active maintainer in 2009.  Once a
        # new release is made (http://pycrypto.org/) we should add an installer.
        try:
            import Crypto
        except ImportError:
            logging.error('Please run "sudo apt-get install python-crypto" '
                          'or your Linux distro\'s equivalent.')
            return False
        return True


    def _build_and_install_current_dir(self, install_dir):
        if not self._check_for_pycrypto():
            return False
        # paramiko 1.7.4 doesn't require building, it is just a module directory
        # that we can rsync into place directly.
        if not os.path.isdir('paramiko'):
            raise Error('no paramiko directory in %s.' % os.getcwd())
        status = system("rsync -r 'paramiko' '%s/'" % install_dir)
        if status:
            logging.error('%s rsync to install_dir failed.' % self.name)
            return False
        return True


class SimplejsonPackage(ExternalPackage):
    version = '2.0.9'
    local_filename = 'simplejson-%s.tar.gz' % version
    urls = ('http://pypi.python.org/packages/source/s/simplejson/' +
            local_filename,)
    hex_sum = 'b5b26059adbe677b06c299bed30557fcb0c7df8c'

    _build_and_install = ExternalPackage._build_and_install_from_package
    _build_and_install_current_dir = (
                        ExternalPackage._build_and_install_current_dir_setup_py)


class Httplib2Package(ExternalPackage):
    version = '0.6.0'
    local_filename = 'httplib2-%s.tar.gz' % version
    urls = ('http://httplib2.googlecode.com/files/' + local_filename,)
    hex_sum = '995344b2704826cc0d61a266e995b328d92445a5'

    def _get_installed_version_from_module(self, module):
        # httplib2 doesn't contain a proper version
        return self.version

    _build_and_install = ExternalPackage._build_and_install_from_package
    _build_and_install_current_dir = (
                        ExternalPackage._build_and_install_current_dir_noegg)


class GwtPackage(ExternalPackage):
    """Fetch and extract a local copy of GWT used to build the frontend."""

    version = '2.3.0'
    local_filename = 'gwt-%s.zip' % version
    urls = ('http://google-web-toolkit.googlecode.com/files/' + local_filename,)
    hex_sum = 'd51fce9166e6b31349659ffca89baf93e39bc84b'
    name = 'gwt'
    about_filename = 'about.txt'
    module_name = None  # Not a Python module.


    def is_needed(self, install_dir):
        gwt_dir = os.path.join(install_dir, self.name)
        about_file = os.path.join(install_dir, self.name, self.about_filename)

        if not os.path.exists(gwt_dir) or not os.path.exists(about_file):
            logging.info('gwt not installed for autotest')
            return True

        f = open(about_file, 'r')
        version_line = f.readline()
        f.close()

        match = re.match(r'Google Web Toolkit (.*)', version_line)
        if not match:
            logging.info('did not find gwt version')
            return True

        logging.info('found gwt version %s', match.group(1))
        return match.group(1) != self.version


    def _build_and_install(self, install_dir):
        os.chdir(install_dir)
        self._extract_compressed_package()
        extracted_dir = self.local_filename[:-len('.zip')]
        target_dir = os.path.join(install_dir, self.name)
        if os.path.exists(target_dir):
            shutil.rmtree(target_dir)
        os.rename(extracted_dir, target_dir)
        return True


class GVizAPIPackage(ExternalPackage):
    version = '1.7.0'
    url_filename = 'gviz_api_py-%s.tar.gz' % version
    local_filename = 'google-visualization-python.tar.gz'
    urls = ('http://google-visualization-python.googlecode.com/files/%s' % (
        url_filename),)
    hex_sum = 'cd9a0fb4ca5c4f86c0d85756f501fd54ccf492d2'

    _build_and_install = ExternalPackage._build_and_install_from_package
    _build_and_install_current_dir = (
                        ExternalPackage._build_and_install_current_dir_noegg)