#!/usr/bin/env python

"""
This sample application shows how to extend one of the basic objects, an Analog
Value Object in this case, to provide a present value. This type of code is used
when the application is providing a BACnet interface to a collection of data.
It assumes that almost all of the default behaviour of a BACpypes application is
sufficient.
"""

import os
import random

from bacpypes.debugging import bacpypes_debugging, ModuleLogger
from bacpypes.consolelogging import ConfigArgumentParser

from bacpypes.core import run

from bacpypes.primitivedata import Real
from bacpypes.app import LocalDeviceObject, BIPSimpleApplication
from bacpypes.object import AnalogValueObject, Property, register_object_type
from bacpypes.errors import ExecutionError

# some debugging
_debug = 0
_log = ModuleLogger(globals())

# settings
RANDOM_OBJECT_COUNT = int(os.getenv('RANDOM_OBJECT_COUNT', 10))

# globals
this_device = None
this_application = None

#
#   RandomValueProperty
#

@bacpypes_debugging
class RandomValueProperty(Property):

    def __init__(self, identifier):
        if _debug: RandomValueProperty._debug("__init__ %r", identifier)
        Property.__init__(self, identifier, Real, default=0.0, optional=True, mutable=False)

    def ReadProperty(self, obj, arrayIndex=None):
        if _debug: RandomValueProperty._debug("ReadProperty %r arrayIndex=%r", obj, arrayIndex)

        # access an array
        if arrayIndex is not None:
            raise ExecutionError(errorClass='property', errorCode='propertyIsNotAnArray')

        # return a random value
        value = random.random() * 100.0
        if _debug: RandomValueProperty._debug("    - value: %r", value)

        return value

    def WriteProperty(self, obj, value, arrayIndex=None, priority=None, direct=False):
        if _debug: RandomValueProperty._debug("WriteProperty %r %r arrayIndex=%r priority=%r direct=%r", obj, value, arrayIndex, priority, direct)
        raise ExecutionError(errorClass='property', errorCode='writeAccessDenied')

#
#   Random Value Object Type
#

@bacpypes_debugging
class RandomAnalogValueObject(AnalogValueObject):

    properties = [
        RandomValueProperty('presentValue'),
        ]

    def __init__(self, **kwargs):
        if _debug: RandomAnalogValueObject._debug("__init__ %r", kwargs)
        AnalogValueObject.__init__(self, **kwargs)

register_object_type(RandomAnalogValueObject)

#
#   __main__
#

def main():
    # parse the command line arguments
    args = ConfigArgumentParser(description=__doc__).parse_args()

    if _debug: _log.debug("initialization")
    if _debug: _log.debug("    - args: %r", args)

    # make a device object
    this_device = LocalDeviceObject(
        objectName=args.ini.objectname,
        objectIdentifier=('device', int(args.ini.objectidentifier)),
        maxApduLengthAccepted=int(args.ini.maxapdulengthaccepted),
        segmentationSupported=args.ini.segmentationsupported,
        vendorIdentifier=int(args.ini.vendoridentifier),
        )

    # make a sample application
    this_application = BIPSimpleApplication(this_device, args.ini.address)

    # get the services supported
    services_supported = this_application.get_services_supported()
    if _debug: _log.debug("    - services_supported: %r", services_supported)

    # let the device object know
    this_device.protocolServicesSupported = services_supported.value

    # make some random input objects
    for i in range(1, RANDOM_OBJECT_COUNT+1):
        ravo = RandomAnalogValueObject(
            objectIdentifier=('analogValue', i),
            objectName='Random-%d' % (i,),
            )
        _log.debug("    - ravo: %r", ravo)
        this_application.add_object(ravo)

    # make sure they are all there
    _log.debug("    - object list: %r", this_device.objectList)

    _log.debug("running")

    run()

    _log.debug("fini")


if __name__ == "__main__":
    main()