"""
Helper functions for invoking Ant tasks
"""
from org.apache.tools.ant import IntrospectionHelper
from org.apache.tools.ant import RuntimeConfigurable

from types import *

def nested(**attrs):
    return attrs

class PAnt:
    
    def __init__(self, proj):
        self.proj=proj
        
    # Assume it's an Ant task
    def __getattr__(self, method):
        # print "Creating task :"+method
        return lambda **attrs: self.execTask(method, **attrs) 
    
    def execTask( self, name, **attrs):
        t=self.createTask(name, **attrs)
        t.execute()

    def createTask( self, name, **attrs):

        t=self.proj.createTask(name)
        conf=t.getRuntimeConfigurableWrapper()
        self.configureElement(t, conf, attrs)
        t.maybeConfigure()

        return t

    def createNestedElement(self, parent, name, attrs):

        name=self.convertToAntName(name)

        ih=IntrospectionHelper.getHelper(self.proj, parent.getClass());
        child = ih.createElement(self.proj, parent, name)
        conf=RuntimeConfigurable(child, name)
        self.configureElement(child, conf, attrs)
        conf.maybeConfigure(self.proj)

        return conf


    """
    In order to be able to specify a repetitive groups in a dictionary, 
    users can add suffixes to make each nested element unique, e.g., 
    env_1, env_2.
    PAnt gets rid of that suffix, incl. the underscore.
    """
    def convertToAntName( self, name ):
        antName=name
        underscoreI = name.rfind("_")
        if underscoreI>=0:
            antName=name[0:underscoreI]
        return antName

    def configureElement(self, owner, conf, attrs):
        for attrName, attrVal in attrs.iteritems():
            #print "Configuring attr %s=%s" % (attrName, attrVal) 
            if type(attrVal) is DictType:
                nConf=self.createNestedElement(owner, attrName, attrVal)
                conf.addChild(nConf)
            else:
                conf.setAttribute(attrName, attrVal)



    def createProps(self, dict):
        
        for propName, propVal in dict.iteritems():
            self.proj.setNewProperty(propName, propVal)