import os.path
from distutils.core import Command
from distutils.command.build import build
from distutils.util import byte_compile
from distutils.dir_util import mkpath

def generate_version(dir, data_dir, version):
    """
    Create a file gaphor/version.py which contains the current version.
    """
    outfile = os.path.join(dir, 'gaphor', 'version.py')
    print 'generating %s' % outfile, dir, data_dir
    mkpath(os.path.dirname(outfile))
    f = open(outfile, 'w')
    f.write('"""\nVersion information generated by setup.py. DO NOT EDIT.\n"""\n\n')
    f.write('VERSION=\'%s\'\n' % version)
    # expand backspaces
    f.write('DATA_DIR=\'%s\'\n' % data_dir.replace('\\', '\\\\'))
    if os.name == 'nt':
        home = 'USERPROFILE'
    else:
        home = 'HOME'
    f.write('import os\n')
    f.write('USER_DATA_DIR=os.path.join(os.getenv(\'%s\'), \'.gaphor\')\n' % home)
    f.write('del os\n')
    f.close()
    byte_compile([outfile])


class build_version(Command):

    user_options = [
        ('build-lib=','b', "build directory (where to install from)"),
        ('force', 'f', "force installation (overwrite existing files)"),
        ('data-dir', None, "data directory (where images and plugins reside)"),
        ]
    boolean_options = [ 'force' ]

    def initialize_options(self):
        self.build_lib = None
        self.force = 0
        self.data_dir = None

    def finalize_options(self):
            self.set_undefined_options('build',
                                       ('build_purelib', 'build_lib'),
                                       ('force', 'force'))
            self.data_dir = os.path.join(os.getcwd(), 'data')

    def run(self):
        generate_version(self.build_lib, self.data_dir,
           self.distribution.get_version())

build.sub_commands.insert(0, ('build_version', None))