/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License
 */

package com.android.incallui;

import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_ADD_CALL;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_AUDIO;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_DIALPAD;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_DOWNGRADE_TO_AUDIO;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_HOLD;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_MERGE;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_MUTE;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_PAUSE_VIDEO;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_SWAP;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_SWITCH_CAMERA;
import static com.android.incallui.CallButtonFragment.Buttons.BUTTON_UPGRADE_TO_VIDEO;

import android.content.Context;
import android.os.Build;
import android.os.Bundle;
import android.telecom.CallAudioState;
import android.telecom.InCallService.VideoCall;
import android.telecom.VideoProfile;

import com.android.contacts.common.compat.CallSdkCompat;
import com.android.contacts.common.compat.SdkVersionOverride;
import com.android.dialer.compat.UserManagerCompat;
import com.android.incallui.AudioModeProvider.AudioModeListener;
import com.android.incallui.InCallCameraManager.Listener;
import com.android.incallui.InCallPresenter.CanAddCallListener;
import com.android.incallui.InCallPresenter.InCallDetailsListener;
import com.android.incallui.InCallPresenter.InCallState;
import com.android.incallui.InCallPresenter.InCallStateListener;
import com.android.incallui.InCallPresenter.IncomingCallListener;

/**
 * Logic for call buttons.
 */
public class CallButtonPresenter extends Presenter<CallButtonPresenter.CallButtonUi>
        implements InCallStateListener, AudioModeListener, IncomingCallListener,
        InCallDetailsListener, CanAddCallListener, Listener {

    private static final String KEY_AUTOMATICALLY_MUTED = "incall_key_automatically_muted";
    private static final String KEY_PREVIOUS_MUTE_STATE = "incall_key_previous_mute_state";

    private Call mCall;
    private boolean mAutomaticallyMuted = false;
    private boolean mPreviousMuteState = false;

    public CallButtonPresenter() {
    }

    @Override
    public void onUiReady(CallButtonUi ui) {
        super.onUiReady(ui);

        AudioModeProvider.getInstance().addListener(this);

        // register for call state changes last
        final InCallPresenter inCallPresenter = InCallPresenter.getInstance();
        inCallPresenter.addListener(this);
        inCallPresenter.addIncomingCallListener(this);
        inCallPresenter.addDetailsListener(this);
        inCallPresenter.addCanAddCallListener(this);
        inCallPresenter.getInCallCameraManager().addCameraSelectionListener(this);

        // Update the buttons state immediately for the current call
        onStateChange(InCallState.NO_CALLS, inCallPresenter.getInCallState(),
                CallList.getInstance());
    }

    @Override
    public void onUiUnready(CallButtonUi ui) {
        super.onUiUnready(ui);

        InCallPresenter.getInstance().removeListener(this);
        AudioModeProvider.getInstance().removeListener(this);
        InCallPresenter.getInstance().removeIncomingCallListener(this);
        InCallPresenter.getInstance().removeDetailsListener(this);
        InCallPresenter.getInstance().getInCallCameraManager().removeCameraSelectionListener(this);
        InCallPresenter.getInstance().removeCanAddCallListener(this);
    }

    @Override
    public void onStateChange(InCallState oldState, InCallState newState, CallList callList) {
        CallButtonUi ui = getUi();

        if (newState == InCallState.OUTGOING) {
            mCall = callList.getOutgoingCall();
        } else if (newState == InCallState.INCALL) {
            mCall = callList.getActiveOrBackgroundCall();

            // When connected to voice mail, automatically shows the dialpad.
            // (On previous releases we showed it when in-call shows up, before waiting for
            // OUTGOING.  We may want to do that once we start showing "Voice mail" label on
            // the dialpad too.)
            if (ui != null) {
                if (oldState == InCallState.OUTGOING && mCall != null) {
                    if (CallerInfoUtils.isVoiceMailNumber(ui.getContext(), mCall)) {
                        ui.displayDialpad(true /* show */, true /* animate */);
                    }
                }
            }
        } else if (newState == InCallState.INCOMING) {
            if (ui != null) {
                ui.displayDialpad(false /* show */, true /* animate */);
            }
            mCall = callList.getIncomingCall();
        } else {
            mCall = null;
        }
        updateUi(newState, mCall);
    }

    /**
     * Updates the user interface in response to a change in the details of a call.
     * Currently handles changes to the call buttons in response to a change in the details for a
     * call.  This is important to ensure changes to the active call are reflected in the available
     * buttons.
     *
     * @param call The active call.
     * @param details The call details.
     */
    @Override
    public void onDetailsChanged(Call call, android.telecom.Call.Details details) {
        // Only update if the changes are for the currently active call
        if (getUi() != null && call != null && call.equals(mCall)) {
            updateButtonsState(call);
        }
    }

    @Override
    public void onIncomingCall(InCallState oldState, InCallState newState, Call call) {
        onStateChange(oldState, newState, CallList.getInstance());
    }

    @Override
    public void onCanAddCallChanged(boolean canAddCall) {
        if (getUi() != null && mCall != null) {
            updateButtonsState(mCall);
        }
    }

    @Override
    public void onAudioMode(int mode) {
        if (getUi() != null) {
            getUi().setAudio(mode);
        }
    }

    @Override
    public void onSupportedAudioMode(int mask) {
        if (getUi() != null) {
            getUi().setSupportedAudio(mask);
        }
    }

    @Override
    public void onMute(boolean muted) {
        if (getUi() != null && !mAutomaticallyMuted) {
            getUi().setMute(muted);
        }
    }

    public int getAudioMode() {
        return AudioModeProvider.getInstance().getAudioMode();
    }

    public int getSupportedAudio() {
        return AudioModeProvider.getInstance().getSupportedModes();
    }

    public void setAudioMode(int mode) {

        // TODO: Set a intermediate state in this presenter until we get
        // an update for onAudioMode().  This will make UI response immediate
        // if it turns out to be slow

        Log.d(this, "Sending new Audio Mode: " + CallAudioState.audioRouteToString(mode));
        TelecomAdapter.getInstance().setAudioRoute(mode);
    }

    /**
     * Function assumes that bluetooth is not supported.
     */
    public void toggleSpeakerphone() {
        // this function should not be called if bluetooth is available
        if (0 != (CallAudioState.ROUTE_BLUETOOTH & getSupportedAudio())) {

            // It's clear the UI is wrong, so update the supported mode once again.
            Log.e(this, "toggling speakerphone not allowed when bluetooth supported.");
            getUi().setSupportedAudio(getSupportedAudio());
            return;
        }

        int newMode = CallAudioState.ROUTE_SPEAKER;

        // if speakerphone is already on, change to wired/earpiece
        if (getAudioMode() == CallAudioState.ROUTE_SPEAKER) {
            newMode = CallAudioState.ROUTE_WIRED_OR_EARPIECE;
        }

        setAudioMode(newMode);
    }

    public void muteClicked(boolean checked) {
        Log.d(this, "turning on mute: " + checked);
        TelecomAdapter.getInstance().mute(checked);
    }

    public void holdClicked(boolean checked) {
        if (mCall == null) {
            return;
        }
        if (checked) {
            Log.i(this, "Putting the call on hold: " + mCall);
            TelecomAdapter.getInstance().holdCall(mCall.getId());
        } else {
            Log.i(this, "Removing the call from hold: " + mCall);
            TelecomAdapter.getInstance().unholdCall(mCall.getId());
        }
    }

    public void swapClicked() {
        if (mCall == null) {
            return;
        }

        Log.i(this, "Swapping the call: " + mCall);
        TelecomAdapter.getInstance().swap(mCall.getId());
    }

    public void mergeClicked() {
        TelecomAdapter.getInstance().merge(mCall.getId());
    }

    public void addCallClicked() {
        // Automatically mute the current call
        mAutomaticallyMuted = true;
        mPreviousMuteState = AudioModeProvider.getInstance().getMute();
        // Simulate a click on the mute button
        muteClicked(true);
        TelecomAdapter.getInstance().addCall();
    }

    public void changeToVoiceClicked() {
        VideoCall videoCall = mCall.getVideoCall();
        if (videoCall == null) {
            return;
        }

        VideoProfile videoProfile = new VideoProfile(VideoProfile.STATE_AUDIO_ONLY);
        videoCall.sendSessionModifyRequest(videoProfile);
    }

    public void showDialpadClicked(boolean checked) {
        Log.v(this, "Show dialpad " + String.valueOf(checked));
        getUi().displayDialpad(checked /* show */, true /* animate */);
    }

    public void changeToVideoClicked() {
        VideoCall videoCall = mCall.getVideoCall();
        if (videoCall == null) {
            return;
        }
        int currVideoState = mCall.getVideoState();
        int currUnpausedVideoState = VideoUtils.getUnPausedVideoState(currVideoState);
        currUnpausedVideoState |= VideoProfile.STATE_BIDIRECTIONAL;

        VideoProfile videoProfile = new VideoProfile(currUnpausedVideoState);
        videoCall.sendSessionModifyRequest(videoProfile);
        mCall.setSessionModificationState(Call.SessionModificationState.WAITING_FOR_RESPONSE);
    }

    /**
     * Switches the camera between the front-facing and back-facing camera.
     * @param useFrontFacingCamera True if we should switch to using the front-facing camera, or
     *     false if we should switch to using the back-facing camera.
     */
    public void switchCameraClicked(boolean useFrontFacingCamera) {
        InCallCameraManager cameraManager = InCallPresenter.getInstance().getInCallCameraManager();
        cameraManager.setUseFrontFacingCamera(useFrontFacingCamera);

        VideoCall videoCall = mCall.getVideoCall();
        if (videoCall == null) {
            return;
        }

        String cameraId = cameraManager.getActiveCameraId();
        if (cameraId != null) {
            final int cameraDir = cameraManager.isUsingFrontFacingCamera()
                    ? Call.VideoSettings.CAMERA_DIRECTION_FRONT_FACING
                    : Call.VideoSettings.CAMERA_DIRECTION_BACK_FACING;
            mCall.getVideoSettings().setCameraDir(cameraDir);
            videoCall.setCamera(cameraId);
            videoCall.requestCameraCapabilities();
        }
    }


    /**
     * Stop or start client's video transmission.
     * @param pause True if pausing the local user's video, or false if starting the local user's
     *    video.
     */
    public void pauseVideoClicked(boolean pause) {
        VideoCall videoCall = mCall.getVideoCall();
        if (videoCall == null) {
            return;
        }

        final int currUnpausedVideoState = VideoUtils.getUnPausedVideoState(mCall.getVideoState());
        if (pause) {
            videoCall.setCamera(null);
            VideoProfile videoProfile = new VideoProfile(currUnpausedVideoState
                    & ~VideoProfile.STATE_TX_ENABLED);
            videoCall.sendSessionModifyRequest(videoProfile);
        } else {
            InCallCameraManager cameraManager = InCallPresenter.getInstance().
                    getInCallCameraManager();
            videoCall.setCamera(cameraManager.getActiveCameraId());
            VideoProfile videoProfile = new VideoProfile(currUnpausedVideoState
                    | VideoProfile.STATE_TX_ENABLED);
            videoCall.sendSessionModifyRequest(videoProfile);
            mCall.setSessionModificationState(Call.SessionModificationState.WAITING_FOR_RESPONSE);
        }
        getUi().setVideoPaused(pause);
    }

    private void updateUi(InCallState state, Call call) {
        Log.d(this, "Updating call UI for call: ", call);

        final CallButtonUi ui = getUi();
        if (ui == null) {
            return;
        }

        final boolean isEnabled =
                state.isConnectingOrConnected() &&!state.isIncoming() && call != null;
        ui.setEnabled(isEnabled);

        if (call == null) {
            return;
        }

        updateButtonsState(call);
    }

    /**
     * Updates the buttons applicable for the UI.
     *
     * @param call The active call.
     */
    private void updateButtonsState(Call call) {
        Log.v(this, "updateButtonsState");
        final CallButtonUi ui = getUi();
        final boolean isVideo = VideoUtils.isVideoCall(call);

        // Common functionality (audio, hold, etc).
        // Show either HOLD or SWAP, but not both. If neither HOLD or SWAP is available:
        //     (1) If the device normally can hold, show HOLD in a disabled state.
        //     (2) If the device doesn't have the concept of hold/swap, remove the button.
        final boolean showSwap = call.can(
                android.telecom.Call.Details.CAPABILITY_SWAP_CONFERENCE);
        final boolean showHold = !showSwap
                && call.can(android.telecom.Call.Details.CAPABILITY_SUPPORT_HOLD)
                && call.can(android.telecom.Call.Details.CAPABILITY_HOLD);
        final boolean isCallOnHold = call.getState() == Call.State.ONHOLD;

        final boolean showAddCall = TelecomAdapter.getInstance().canAddCall()
                && UserManagerCompat.isUserUnlocked(ui.getContext());
        final boolean showMerge = call.can(
                android.telecom.Call.Details.CAPABILITY_MERGE_CONFERENCE);
        final boolean showUpgradeToVideo = !isVideo && hasVideoCallCapabilities(call);
        final boolean showDowngradeToAudio = isVideo && isDowngradeToAudioSupported(call);
        final boolean showMute = call.can(android.telecom.Call.Details.CAPABILITY_MUTE);

        ui.showButton(BUTTON_AUDIO, true);
        ui.showButton(BUTTON_SWAP, showSwap);
        ui.showButton(BUTTON_HOLD, showHold);
        ui.setHold(isCallOnHold);
        ui.showButton(BUTTON_MUTE, showMute);
        ui.showButton(BUTTON_ADD_CALL, showAddCall);
        ui.showButton(BUTTON_UPGRADE_TO_VIDEO, showUpgradeToVideo);
        ui.showButton(BUTTON_DOWNGRADE_TO_AUDIO, showDowngradeToAudio);
        ui.showButton(BUTTON_SWITCH_CAMERA, isVideo);
        ui.showButton(BUTTON_PAUSE_VIDEO, isVideo);
        if (isVideo) {
            getUi().setVideoPaused(!VideoUtils.isTransmissionEnabled(call));
        }
        ui.showButton(BUTTON_DIALPAD, true);
        ui.showButton(BUTTON_MERGE, showMerge);

        ui.updateButtonStates();
    }

    private boolean hasVideoCallCapabilities(Call call) {
        if (SdkVersionOverride.getSdkVersion(Build.VERSION_CODES.M) >= Build.VERSION_CODES.M) {
            return call.can(android.telecom.Call.Details.CAPABILITY_SUPPORTS_VT_LOCAL_TX)
                    && call.can(android.telecom.Call.Details.CAPABILITY_SUPPORTS_VT_REMOTE_RX);
        }
        // In L, this single flag represents both video transmitting and receiving capabilities
        return call.can(android.telecom.Call.Details.CAPABILITY_SUPPORTS_VT_LOCAL_TX);
    }

    /**
     * Determines if downgrading from a video call to an audio-only call is supported.  In order to
     * support downgrade to audio, the SDK version must be >= N and the call should NOT have the
     * {@link android.telecom.Call.Details#CAPABILITY_CANNOT_DOWNGRADE_VIDEO_TO_AUDIO}.
     * @param call The call.
     * @return {@code true} if downgrading to an audio-only call from a video call is supported.
     */
    private boolean isDowngradeToAudioSupported(Call call) {
        return !call.can(CallSdkCompat.Details.CAPABILITY_CANNOT_DOWNGRADE_VIDEO_TO_AUDIO);
    }

    public void refreshMuteState() {
        // Restore the previous mute state
        if (mAutomaticallyMuted &&
                AudioModeProvider.getInstance().getMute() != mPreviousMuteState) {
            if (getUi() == null) {
                return;
            }
            muteClicked(mPreviousMuteState);
        }
        mAutomaticallyMuted = false;
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putBoolean(KEY_AUTOMATICALLY_MUTED, mAutomaticallyMuted);
        outState.putBoolean(KEY_PREVIOUS_MUTE_STATE, mPreviousMuteState);
    }

    @Override
    public void onRestoreInstanceState(Bundle savedInstanceState) {
        mAutomaticallyMuted =
                savedInstanceState.getBoolean(KEY_AUTOMATICALLY_MUTED, mAutomaticallyMuted);
        mPreviousMuteState =
                savedInstanceState.getBoolean(KEY_PREVIOUS_MUTE_STATE, mPreviousMuteState);
        super.onRestoreInstanceState(savedInstanceState);
    }

    public interface CallButtonUi extends Ui {
        void showButton(int buttonId, boolean show);
        void enableButton(int buttonId, boolean enable);
        void setEnabled(boolean on);
        void setMute(boolean on);
        void setHold(boolean on);
        void setCameraSwitched(boolean isBackFacingCamera);
        void setVideoPaused(boolean isPaused);
        void setAudio(int mode);
        void setSupportedAudio(int mask);
        void displayDialpad(boolean on, boolean animate);
        boolean isDialpadVisible();

        /**
         * Once showButton() has been called on each of the individual buttons in the UI, call
         * this to configure the overflow menu appropriately.
         */
        void updateButtonStates();
        Context getContext();
    }

    @Override
    public void onActiveCameraSelectionChanged(boolean isUsingFrontFacingCamera) {
        if (getUi() == null) {
            return;
        }
        getUi().setCameraSwitched(!isUsingFrontFacingCamera);
    }
}