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# -*- coding: utf-8 -*-
'''recorder.py
Provides WAV recording functionality via two approaches:

Blocking mode (record for a set duration):
>>> rec = Recorder(channels=2)
>>> with rec.open('blocking.wav', 'wb') as recfile:
...     recfile.record(duration=5.0)

Non-blocking mode (start and stop recording):

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# The slow way
class Person:
    def __init__(self, name, occupation):
        self.name = name
        self.occupation = occupation
        self.relatives = self._get_all_relatives()
        
    def _get_all_relatives():
        ...
        # This is an expensive operation

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# Better
class Person:
    def __init__(self, name, occupation):
        self.name = name
        self.occupation = occupation
        self._relatives = None
        
    @property
    def relatives(self):
        if self._relatives is None:

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# Even better

def lazy_property(fn):
    '''Decorator that makes a property lazy-evaluated.
    '''
    attr_name = '_lazy_' + fn.__name__

    @property
    def _lazy_property(self):
        if not hasattr(self, attr_name):

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class Boiler:
    def safety_check(self):
        # Convert fixed-point floating point
        temperature = self.modbus.read_holding()
        pressure_psi = self.abb_f100.register / F100_FACTOR
        if (psi_to_pascal(pressure_psi) > MAX_PRESSURE or
                temperature > MAX_TEMPERATURE):
            # Shutdown!
            self.pnoz.relay[15] &= MASK_POWER_COIL
            self.pnoz.port.write('$PL,15\0')

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# Better
class Boiler:
    def safety_check(self):
        if any([self.temperature > MAX_TEMPERATURE,
                self.pressure > MAX_PRESSURE]):
            if not self.shutdown():
                self.alarm()

    def alarm(self):
        with open(BUZZER_MP3_FILE) as f:

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# At initiation `point` is not well-formed
point = Point()
point.x = 12
point.y = 5

# Better
point = Point(x=12, y=5)

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class Point:
    def __init__(self, x, y):
        self.x, self.y = x, y

    @classmethod
    def polar(cls, r, theta):
        return cls(r * cos(theta),
                   r * sin(theta))

point = Point.polar(r=13, theta=22.6)

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def send_task(self, task, job, obligation):
    ...
    processed = ...
    ...
    copied = ...
    ...
    executed = ...
    100 more lines

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class TaskSender:
    def __init__(self, task, job obligation):
        self.task = task
        self.job = job
        self.obligation = obligation
        self.processed = []
        self.copied = []
        self.executed = []

    def __call__(self):