"""
Example of usage of ConfigurableUser classes (for high level configuration).
"""
from Gaudi.Configuration import *

class ExampleIO(ConfigurableUser):
    __slots__ = { "EvtMax": 1,
                  "Read" : "NONE", 
                  "Write" : "NONE" }
    __used_configurables__ = [ ApplicationMgr ]
    def __apply_configuration__(self):
        # Propagate the properties to all used configurables
        # In this case the only effect is to set the ApplicationMgr EvtMax.
        self.propagateProperties()
        
        read = self.getProp("Read")
        if read == "NONE":
            ApplicationMgr(EvtSel = "NONE")
        else:
            log.warning("%s: Cannot handle value %r of property Read",
                        self.name(), read )
        
        write = self.getProp("Write")
        if read == "NONE":
            ApplicationMgr(HistogramPersistency = "NONE")
        else:
            log.warning("%s: Cannot handle value %r of property Write",
                        self.name(), write )

class ExampleCommon(ConfigurableUser):
    __slots__ = { "OutputLevel"     : INFO,
                  "StatusCodeCheck" : False }
    __used_configurables__ = []
    def __apply_configuration__(self):
        ApplicationMgr().StatusCodeCheck = self.getProp("StatusCodeCheck")
        MessageSvc().OutputLevel = self.getProp("OutputLevel")

class ExampleApplication(ConfigurableUser):
    __slots__ = { "FullDebug" : False,
                  "TopAlg" : [],
                   }
    __used_configurables__ = [ ExampleCommon, ApplicationMgr ]
    def __apply_configuration__(self):
        if self.getProp("FullDebug"):
            ExampleCommon(OutputLevel = VERBOSE,
                          StatusCodeCheck = True)
        else:
            ExampleCommon(OutputLevel = INFO,
                          StatusCodeCheck = False)
        # Propagate the properties to all used configurables
        # In this case the only effect is to set the ApplicationMgr TopAlg.
        self.propagateProperties()


def PostConfAction():
    """
    Action printing the result of the configuration of the ApplicationMgr.
    """
    print "==== Configuration completed ===="
    print ApplicationMgr()

appendPostConfigAction(PostConfAction)


ExampleApplication(TopAlg = [ "GaudiExamples::TimingAlg/Timing" ],
                   FullDebug = True)
ExampleIO(EvtMax = 10)