#!/usr/bin/env
#python
"""Updates module version based on the status of the git tree."""

import os
import time
import logging

import git

class VersionBumper(object):
    """Tool for automagically updating the module version."""
    
    def __init__(self, module):
        """Initializes a VersionBumper."""
        super(VersionBumper, self).__init__(self)

        self.module = module
        self.repo = git.Repo(module.__file__)
        
        logging.debug("Created %s for module %s." % (repr(self), module))

    def getBranch(self):
        """Returns the name of the current branch."""
        return self.repo.branch().split()[1]

    branch = property(fget = getBranch, doc = """The current git branch.""")

    def getTag(self):
        """Returns the name of the current tag."""
        return self.repo.git.tag()

    tag = property(fget = getTag, doc = """The current git tag.""")

    def isRelease(self):
        """Tests if we're currently pointed at a release branch."""
        return 'release' in self.branch

    def getReleaseVersionString(self):
        """Create a version string for a release version."""
        if self.tag:
            return self.tag
        
    def getNightlyVersionString(self):
        """Create a version string for a nightly version."""
        versionStrings = [time.strftime("%Y%m%d")]

        if self.branch != 'master':
            versionStrings.append(self.branch)

        if self.tag:
            versionStrings.append(self.tag)
            
        return '-'.join(versionStrings)

    def getVersionString(self):
        if self.isRelease():
            return self.getReleaseVersionString()
        else:
            return self.getNightlyVersionString()

    version = property(fget = getTag, doc = """The version string.""")
    
    def bump(self):
        """Bumps the version."""
        versionString = "__version__=\"%s\"" % self.version
        initFile = open(self.module.__file__, "w")
        newLines = [line for line in initFile
                    if '__version__' not in line else versionString]
        initFile.writelines(newLines)
        
        
def bumpVersion(module):
    """Bumps the version for a module."""
    repo = git.Repo(module.__file__)
    branch = repo.git.branch().split()[1]

    if 'release' in branch:
        logging.info("Detected a release branch (%s)..." % branch)
        version = repo.git.tag()
    else:
        logging.info("Detected a nightly branch (%s)..." % branch)
        version = time.strftime("%Y%m%d")
        if branch != "master":
            logging.debug("Branch is not master, adding to version...")
            version = '%s-%s' % (version, branch)

    logging.info("Created version string (%s)..." % version)