# Copyright 2014 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""This module provides the audio widgets used in audio tests."""

import abc
import copy
import logging
import tempfile

from autotest_lib.client.cros.audio import audio_data
from autotest_lib.client.cros.audio import audio_test_data
from autotest_lib.client.cros.audio import sox_utils
from autotest_lib.client.cros.chameleon import chameleon_audio_ids as ids
from autotest_lib.client.cros.chameleon import chameleon_port_finder


class AudioWidget(object):
    """
    This class abstracts an audio widget in audio test framework. A widget
    is identified by its audio port. The handler passed in at __init__ will
    handle action on the audio widget.

    Properties:
        audio_port: The AudioPort this AudioWidget resides in.
        handler: The handler that handles audio action on the widget. It is
                  actually a (Chameleon/Cros)(Input/Output)WidgetHandler object.

    """
    def __init__(self, audio_port, handler):
        """Initializes an AudioWidget on a AudioPort.

        @param audio_port: An AudioPort object.
        @param handler: A WidgetHandler object which handles action on the widget.

        """
        self.audio_port = audio_port
        self.handler = handler


    @property
    def port_id(self):
        """Port id of this audio widget.

        @returns: A string. The port id defined in chameleon_audio_ids for this
                  audio widget.
        """
        return self.audio_port.port_id


class AudioInputWidget(AudioWidget):
    """
    This class abstracts an audio input widget. This class provides the audio
    action that is available on an input audio port.

    Properties:
        _rec_binary: The recorded binary data.
        _rec_format: The recorded data format. A dict containing
                     file_type: 'raw' or 'wav'.
                     sample_format: 'S32_LE' for 32-bit signed integer in
                                    little-endian. Refer to aplay manpage for
                                    other formats.
                     channel: channel number.
                     rate: sampling rate.

        _channel_map: A list containing current channel map. Checks docstring
                      of channel_map method for details.

    """
    def __init__(self, *args, **kwargs):
        """Initializes an AudioInputWidget."""
        super(AudioInputWidget, self).__init__(*args, **kwargs)
        self._rec_binary = None
        self._rec_format = None
        self._channel_map = None
        self._init_channel_map_without_link()


    def start_recording(self):
        """Starts recording."""
        self._rec_binary = None
        self._rec_format = None
        self.handler.start_recording()


    def stop_recording(self):
        """Stops recording."""
        self._rec_binary, self._rec_format = self.handler.stop_recording()


    def save_file(self, file_path):
        """Saves recorded data to a file.

        @param file_path: The path to save the file.

        """
        with open(file_path, 'wb') as f:
            logging.debug('Saving recorded raw file to %s', file_path)
            f.write(self._rec_binary)


    def get_binary(self):
        """Gets recorded binary data.

        @returns: The recorded binary data.

        """
        return self._rec_binary


    @property
    def data_format(self):
        """The recorded data format.

        @returns: The recorded data format.

        """
        return self._rec_format


    @property
    def channel_map(self):
        """The recorded data channel map.

        @returns: The recorded channel map. A list containing channel mapping.
                  E.g. [1, 0, None, None, None, None, None, None] means
                  channel 0 of recorded data should be mapped to channel 1 of
                  data played to the recorder. Channel 1 of recorded data should
                  be mapped to channel 0 of data played to recorder.
                  Channel 2 to 7 of recorded data should be ignored.

        """
        return self._channel_map


    @channel_map.setter
    def channel_map(self, new_channel_map):
        """Sets channel map.

        @param new_channel_map: A list containing new channel map.

        """
        self._channel_map = copy.deepcopy(new_channel_map)


    def _init_channel_map_without_link(self):
        """Initializes channel map without WidgetLink.

        WidgetLink sets channel map to a sink widget when the link combines
        a source widget to a sink widget. For simple cases like internal
        microphone on Cros device, or Mic port on Chameleon, the audio signal
        is over the air, so we do not use link to combine the source to
        the sink. We just set a default channel map in this case.

        """
        if self.port_id in [ids.ChameleonIds.MIC, ids.CrosIds.INTERNAL_MIC]:
            self._channel_map = [0]


    @property
    def _sample_size_bytes(self):
        """Gets sample size in bytes of recorded data."""
        return audio_data.SAMPLE_FORMATS[
                self._rec_format['sample_format']]['size_bytes']


    @property
    def _sample_size_bits(self):
        """Gets sample size in bits of recorded data."""
        return self._sample_size_bytes * 8


    @property
    def _channel(self):
        """Gets number of channels of recorded data."""
        return self._rec_format['channel']


    @property
    def _sampling_rate(self):
        """Gets sampling rate of recorded data."""
        return self._rec_format['rate']


    def remove_head(self, duration_secs):
        """Removes a duration of recorded data from head.

        @param duration_secs: The duration in seconds to be removed from head.

        """
        offset = int(self._sampling_rate * duration_secs *
                     self._sample_size_bytes * self._channel)
        self._rec_binary = self._rec_binary[offset:]


    def lowpass_filter(self, frequency):
        """Passes the recorded data to a lowpass filter.

        @param frequency: The 3dB frequency of lowpass filter.

        """
        with tempfile.NamedTemporaryFile(
                prefix='original_') as original_file:
            with tempfile.NamedTemporaryFile(
                    prefix='filtered_') as filtered_file:

                original_file.write(self._rec_binary)
                original_file.flush()

                sox_utils.lowpass_filter(
                        original_file.name, self._channel,
                        self._sample_size_bits, self._sampling_rate,
                        filtered_file.name, frequency)

                self._rec_binary = filtered_file.read()


class AudioOutputWidget(AudioWidget):
    """
    This class abstracts an audio output widget. This class provides the audio
    action that is available on an output audio port.

    """
    def start_playback(self, test_data, blocking=False):
        """Starts playing audio.

        @param test_data: An AudioTestData object.
        @param blocking: Blocks this call until playback finishes.
        """
        self.handler.start_playback(test_data, blocking)


    def stop_playback(self):
        """Stops playing audio."""
        self.handler.stop_playback()


class WidgetHandler(object):
    """This class abstracts handler for basic actions on widget."""
    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def plug(self):
        """Plug this widget."""
        pass


    @abc.abstractmethod
    def unplug(self):
        """Unplug this widget."""
        pass


class ChameleonWidgetHandler(WidgetHandler):
    """
    This class abstracts a Chameleon audio widget handler.

    Properties:
        interface: A string that represents the interface name on
                   Chameleon, e.g. 'HDMI', 'LineIn', 'LineOut'.
        scale: The scale is the scaling factor to be applied on the data of the
               widget before playing or after recording.
        _chameleon_board: A ChameleonBoard object to control Chameleon.
        _port: A ChameleonPort object to control port on Chameleon.

    """
    # The mic port on chameleon has a small gain. We need to scale
    # the recorded value up, otherwise, the recorded value will be
    # too small and will be falsely judged as not meaningful in the
    # processing, even when the recorded audio is clear.
    _DEFAULT_MIC_SCALE = 300.0

    def __init__(self, chameleon_board, interface):
        """Initializes a ChameleonWidgetHandler.

        @param chameleon_board: A ChameleonBoard object.
        @param interface: A string that represents the interface name on
                          Chameleon, e.g. 'HDMI', 'LineIn', 'LineOut'.

        """
        self.interface = interface
        self._chameleon_board = chameleon_board
        self._port = self._find_port(interface)
        self.scale = None
        self._init_scale_without_link()


    @abc.abstractmethod
    def _find_port(self, interface):
        """Finds the port by interface."""
        pass


    def plug(self):
        """Plugs this widget."""
        self._port.plug()


    def unplug(self):
        """Unplugs this widget."""
        self._port.unplug()


    def _init_scale_without_link(self):
        """Initializes scale for widget handler not used with link.

        Audio widget link sets scale when it connects two audio widgets.
        For audio widget not used with link, e.g. Mic on Chameleon, we set
        a default scale here.

        """
        if self.interface == 'Mic':
            self.scale = self._DEFAULT_MIC_SCALE


class ChameleonInputWidgetHandler(ChameleonWidgetHandler):
    """
    This class abstracts a Chameleon audio input widget handler.

    """
    def start_recording(self):
        """Starts recording."""
        self._port.start_capturing_audio()


    def stop_recording(self):
        """Stops recording.

        Gets recorded binary and format from Chameleon. Also, handle scaling
        if needed.

        @returns: A tuple (data_binary, data_format) for recorded data.
                  Refer to stop_capturing_audio call of ChameleonAudioInput.

        """
        with tempfile.NamedTemporaryFile(prefix='recorded_') as f:
            # Gets recorded data and format by Chameleon port.
            rec_binary, rec_format = self._port.stop_capturing_audio()

            # Handles scaling using audio_test_data.
            open(f.name, 'w').write(rec_binary)
            test_data = audio_test_data.AudioTestData(rec_format, f.name)
            converted_test_data = test_data.convert(
                    rec_format, self.scale)
            scaled_binary = converted_test_data.get_binary()
            converted_test_data.delete()

            return scaled_binary, rec_format


    def _find_port(self, interface):
        """Finds a Chameleon audio port by interface(port name).

        @param interface: string, the interface. e.g: HDMI.

        @returns: A ChameleonPort object.

        @raises: ValueError if port is not connected.

        """
        finder = chameleon_port_finder.ChameleonAudioInputFinder(
                self._chameleon_board)
        chameleon_port = finder.find_port(interface)
        if not chameleon_port:
            raise ValueError(
                    'Port %s is not connected to Chameleon' % interface)
        return chameleon_port


class ChameleonOutputWidgetHandler(ChameleonWidgetHandler):
    """
    This class abstracts a Chameleon audio output widget handler.

    """
    _DEFAULT_DATA_FORMAT = dict(file_type='raw',
                                sample_format='S32_LE',
                                channel=8,
                                rate=48000)

    def start_playback(self, test_data, blocking=False):
        """Starts playback.

        @param test_data: An AudioTestData object.
        @param blocking: Blocks this call until playback finishes.

        """
        if blocking:
            raise NotImplementedError(
                    'Blocking playback on chameleon is not supported')

        converted_audio_test_data = test_data.convert(
                self._DEFAULT_DATA_FORMAT, self.scale)

        self._port.start_playing_audio(
                converted_audio_test_data.get_binary(),
                self._DEFAULT_DATA_FORMAT)

        converted_audio_test_data.delete()


    def stop_playback(self):
        """Stops playback."""
        self._port.stop_playing_audio()


    def _find_port(self, interface):
        """Finds a Chameleon audio port by interface(port name).

        @param interface: string, the interface. e.g: LineOut.

        @returns: A ChameleonPort object.

        @raises: ValueError if port is not connected.

        """
        finder = chameleon_port_finder.ChameleonAudioOutputFinder(
                self._chameleon_board)
        chameleon_port = finder.find_port(interface)
        if not chameleon_port:
            raise ValueError(
                    'Port %s is not connected to Chameleon' % interface)
        return chameleon_port


class CrosWidgetHandler(WidgetHandler):
    """
    This class abstracts a Cros device audio widget handler.

    Properties:
        _audio_facade: An AudioFacadeRemoteAdapter to access Cros device
                       audio functionality.

    """
    def __init__(self, audio_facade):
        """Initializes a CrosWidgetHandler.

        @param audio_facade: An AudioFacadeRemoteAdapter to access Cros device
                             audio functionality.

        """
        self._audio_facade = audio_facade


    def plug(self):
        """Plugs this widget."""
        # TODO(cychiang): Implement plug control. This class
        # will need access to ChameleonBoard and interface name.
        # For widget on 3.5mm jack(Headphone and External Mic), we need to
        # plug/unplug 3.5mm jack by fixture controlled by Chameleon.
        pass


    def unplug(self):
        """Unplugs this widget."""
        # TODO(cychiang): Similar to plug().
        pass


class CrosInputWidgetHandler(CrosWidgetHandler):
    """
    This class abstracts a Cros device audio input widget handler.

    """
    _DEFAULT_DATA_FORMAT = dict(file_type='raw',
                                sample_format='S16_LE',
                                channel=1,
                                rate=48000)

    def start_recording(self):
        """Starts recording audio."""
        self._audio_facade.start_recording(self._DEFAULT_DATA_FORMAT)


    def stop_recording(self):
        """Stops recording audio.

        @returns:
            A tuple (data, format).
                data: The recorded binary data.
                format: A dict containing:
                    file_type: 'raw'.
                    sample_format: 'S16_LE' for 16-bit signed integer in
                                   little-endian.
                    channel: channel number.
                    rate: sampling rate.

        """
        with tempfile.NamedTemporaryFile(prefix='recorded_', delete=False) as f:
            self._audio_facade.stop_recording(f.name)
            return open(f.name).read(), self._DEFAULT_DATA_FORMAT


class CrosOutputWidgetHandlerError(Exception):
    """The error in CrosOutputWidgetHandler."""
    pass


class CrosOutputWidgetHandler(CrosWidgetHandler):
    """
    This class abstracts a Cros device audio output widget handler.

    """
    _DEFAULT_DATA_FORMAT = dict(file_type='raw',
                                sample_format='S16_LE',
                                channel=2,
                                rate=48000)

    def start_playback(self, test_data, blocking=False):
        """Starts playing audio.

        @param test_data: An AudioTestData object.
        @param blocking: Blocks this call until playback finishes.

        """
        # TODO(cychiang): Do format conversion on Cros device if this is
        # needed.
        if test_data.data_format != self._DEFAULT_DATA_FORMAT:
            raise CrosOutputWidgetHandlerError(
                    'File format conversion for cros device is not supported.')

        return self._audio_facade.playback(test_data.path, test_data.data_format,
                                           blocking)


    def stop_playback(self):
        """Stops playing audio."""
        raise NotImplementedError


class PeripheralWidgetHandler(object):
    """
    This class abstracts an action handler on peripheral.
    Currently, as there is no action to take on the peripheral speaker and mic,
    this class serves as a place-holder.

    """
    pass