openwebrx-clone/owrx/property/__init__.py
2020-03-22 21:51:49 +01:00

143 lines
3.7 KiB
Python

import logging
logger = logging.getLogger(__name__)
class Subscription(object):
def __init__(self, subscriptee, subscriber):
self.subscriptee = subscriptee
self.subscriber = subscriber
def call(self, *args, **kwargs):
self.subscriber(*args, **kwargs)
def cancel(self):
self.subscriptee.unwire(self)
class Property(object):
def __init__(self, value=None):
self.value = value
self.subscribers = []
def getValue(self):
return self.value
def setValue(self, value):
if self.value == value:
return self
self.value = value
for c in self.subscribers:
try:
c.call(self.value)
except Exception as e:
logger.exception(e)
return self
def wire(self, callback):
sub = Subscription(self, callback)
self.subscribers.append(sub)
if self.value is not None:
sub.call(self.value)
return sub
def unwire(self, sub):
try:
self.subscribers.remove(sub)
except ValueError:
# happens when already removed before
pass
return self
class PropertyManager(object):
def collect(self, *props):
return PropertyManager(
{name: self.getProperty(name) if self.hasProperty(name) else Property() for name in props}
)
def __init__(self, properties=None):
self.properties = {}
self.subscribers = []
if properties is not None:
for (name, prop) in properties.items():
self.add(name, prop)
def add(self, name, prop):
self.properties[name] = prop
def fireCallbacks(value):
for c in self.subscribers:
try:
c.call(name, value)
except Exception as e:
logger.exception(e)
prop.wire(fireCallbacks)
return self
def __contains__(self, name):
return self.hasProperty(name)
def __getitem__(self, name):
return self.getPropertyValue(name)
def __setitem__(self, name, value):
if not self.hasProperty(name):
self.add(name, Property())
self.getProperty(name).setValue(value)
def __dict__(self):
return {k: v.getValue() for k, v in self.properties.items()}
def hasProperty(self, name):
return name in self.properties
def getProperty(self, name):
if not self.hasProperty(name):
self.add(name, Property())
return self.properties[name]
def getPropertyValue(self, name):
return self.getProperty(name).getValue()
def wire(self, callback):
sub = Subscription(self, callback)
self.subscribers.append(sub)
return sub
def unwire(self, sub):
try:
self.subscribers.remove(sub)
except ValueError:
# happens when already removed before
pass
return self
def defaults(self, other_pm):
for (key, p) in self.properties.items():
if p.getValue() is None:
p.setValue(other_pm[key])
return self
class PropertyLayers(object):
def __init__(self):
self.layers = []
def addLayer(self, priority: int, pm: PropertyManager):
"""
highest priority = 0
"""
self.layers.append({"priority": priority, "props": pm})
def removeLayer(self, pm: PropertyManager):
for layer in self.layers:
if layer["props"] == pm:
self.layers.remove(layer)
def __getitem__(self, item):
layers = [la["props"] for la in sorted(self.layers, key=lambda l: l["priority"])]
for m in layers:
if item in m:
return m[item]