/*
 * Copyright (C) 2014 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.systemui.statusbar.phone;

import android.app.ActivityManagerNative;
import android.app.admin.DevicePolicyManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.os.RemoteException;
import android.os.UserHandle;
import android.provider.MediaStore;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.view.accessibility.AccessibilityManager;
import android.widget.FrameLayout;

import com.android.internal.widget.LockPatternUtils;
import com.android.keyguard.KeyguardUpdateMonitor;
import com.android.keyguard.KeyguardUpdateMonitorCallback;
import com.android.systemui.R;
import com.android.systemui.statusbar.KeyguardIndicationController;
import com.android.systemui.statusbar.policy.FlashlightController;
import com.android.systemui.statusbar.KeyguardAffordanceView;
import com.android.systemui.statusbar.policy.PreviewInflater;

/**
 * Implementation for the bottom area of the Keyguard, including camera/phone affordance and status
 * text.
 */
public class KeyguardBottomAreaView extends FrameLayout implements View.OnClickListener,
        UnlockMethodCache.OnUnlockMethodChangedListener {

    final static String TAG = "PhoneStatusBar/KeyguardBottomAreaView";

    private static final Intent SECURE_CAMERA_INTENT =
            new Intent(MediaStore.INTENT_ACTION_STILL_IMAGE_CAMERA_SECURE)
                    .addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
    private static final Intent INSECURE_CAMERA_INTENT =
            new Intent(MediaStore.INTENT_ACTION_STILL_IMAGE_CAMERA);
    private static final Intent PHONE_INTENT = new Intent(Intent.ACTION_DIAL);

    private KeyguardAffordanceView mCameraImageView;
    private KeyguardAffordanceView mPhoneImageView;
    private KeyguardAffordanceView mLockIcon;
    private View mIndicationText;
    private ViewGroup mPreviewContainer;

    private View mPhonePreview;
    private View mCameraPreview;

    private ActivityStarter mActivityStarter;
    private UnlockMethodCache mUnlockMethodCache;
    private LockPatternUtils mLockPatternUtils;
    private FlashlightController mFlashlightController;
    private PreviewInflater mPreviewInflater;
    private KeyguardIndicationController mIndicationController;
    private boolean mFaceUnlockRunning;

    public KeyguardBottomAreaView(Context context) {
        super(context);
    }

    public KeyguardBottomAreaView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public KeyguardBottomAreaView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    public KeyguardBottomAreaView(Context context, AttributeSet attrs, int defStyleAttr,
            int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    @Override
    protected void onFinishInflate() {
        super.onFinishInflate();
        mLockPatternUtils = new LockPatternUtils(mContext);
        mPreviewContainer = (ViewGroup) findViewById(R.id.preview_container);
        mCameraImageView = (KeyguardAffordanceView) findViewById(R.id.camera_button);
        mPhoneImageView = (KeyguardAffordanceView) findViewById(R.id.phone_button);
        mLockIcon = (KeyguardAffordanceView) findViewById(R.id.lock_icon);
        mIndicationText = findViewById(R.id.keyguard_indication_text);
        watchForCameraPolicyChanges();
        watchForAccessibilityChanges();
        updateCameraVisibility();
        updatePhoneVisibility();
        mUnlockMethodCache = UnlockMethodCache.getInstance(getContext());
        mUnlockMethodCache.addListener(this);
        updateLockIcon();
        setClipChildren(false);
        setClipToPadding(false);
        mPreviewInflater = new PreviewInflater(mContext, new LockPatternUtils(mContext));
        inflatePreviews();
        mLockIcon.setOnClickListener(this);
    }

    public void setActivityStarter(ActivityStarter activityStarter) {
        mActivityStarter = activityStarter;
    }

    public void setFlashlightController(FlashlightController flashlightController) {
        mFlashlightController = flashlightController;
    }

    private Intent getCameraIntent() {
        KeyguardUpdateMonitor updateMonitor = KeyguardUpdateMonitor.getInstance(mContext);
        boolean currentUserHasTrust = updateMonitor.getUserHasTrust(
                mLockPatternUtils.getCurrentUser());
        return mLockPatternUtils.isSecure() && !currentUserHasTrust
                ? SECURE_CAMERA_INTENT : INSECURE_CAMERA_INTENT;
    }

    private void updateCameraVisibility() {
        ResolveInfo resolved = mContext.getPackageManager().resolveActivityAsUser(getCameraIntent(),
                PackageManager.MATCH_DEFAULT_ONLY,
                mLockPatternUtils.getCurrentUser());
        boolean visible = !isCameraDisabledByDpm() && resolved != null;
        mCameraImageView.setVisibility(visible ? View.VISIBLE : View.GONE);
    }

    private void updatePhoneVisibility() {
        boolean visible = isPhoneVisible();
        mPhoneImageView.setVisibility(visible ? View.VISIBLE : View.GONE);
    }

    private boolean isPhoneVisible() {
        PackageManager pm = mContext.getPackageManager();
        return pm.hasSystemFeature(PackageManager.FEATURE_TELEPHONY)
                && pm.resolveActivity(PHONE_INTENT, 0) != null;
    }

    private boolean isCameraDisabledByDpm() {
        final DevicePolicyManager dpm =
                (DevicePolicyManager) getContext().getSystemService(Context.DEVICE_POLICY_SERVICE);
        if (dpm != null) {
            try {
                final int userId = ActivityManagerNative.getDefault().getCurrentUser().id;
                final int disabledFlags = dpm.getKeyguardDisabledFeatures(null, userId);
                final  boolean disabledBecauseKeyguardSecure =
                        (disabledFlags & DevicePolicyManager.KEYGUARD_DISABLE_SECURE_CAMERA) != 0
                                && KeyguardTouchDelegate.getInstance(getContext()).isSecure();
                return dpm.getCameraDisabled(null) || disabledBecauseKeyguardSecure;
            } catch (RemoteException e) {
                Log.e(TAG, "Can't get userId", e);
            }
        }
        return false;
    }

    private void watchForCameraPolicyChanges() {
        final IntentFilter filter = new IntentFilter();
        filter.addAction(DevicePolicyManager.ACTION_DEVICE_POLICY_MANAGER_STATE_CHANGED);
        getContext().registerReceiverAsUser(mDevicePolicyReceiver,
                UserHandle.ALL, filter, null, null);
        KeyguardUpdateMonitor.getInstance(mContext).registerCallback(mUpdateMonitorCallback);
    }

    private void watchForAccessibilityChanges() {
        final AccessibilityManager am =
                (AccessibilityManager) getContext().getSystemService(Context.ACCESSIBILITY_SERVICE);

        // Set the initial state
        enableAccessibility(am.isTouchExplorationEnabled());

        // Watch for changes
        am.addTouchExplorationStateChangeListener(
                new AccessibilityManager.TouchExplorationStateChangeListener() {
            @Override
            public void onTouchExplorationStateChanged(boolean enabled) {
                enableAccessibility(enabled);
            }
        });
    }

    private void enableAccessibility(boolean touchExplorationEnabled) {
        mCameraImageView.setOnClickListener(touchExplorationEnabled ? this : null);
        mCameraImageView.setClickable(touchExplorationEnabled);
        mPhoneImageView.setOnClickListener(touchExplorationEnabled ? this : null);
        mPhoneImageView.setClickable(touchExplorationEnabled);
    }

    @Override
    public void onClick(View v) {
        if (v == mCameraImageView) {
            launchCamera();
        } else if (v == mPhoneImageView) {
            launchPhone();
        } if (v == mLockIcon) {
            mIndicationController.showTransientIndication(
                    R.string.keyguard_indication_trust_disabled);
            mLockPatternUtils.requireCredentialEntry(mLockPatternUtils.getCurrentUser());
        }
    }

    public void launchCamera() {
        mFlashlightController.killFlashlight();
        Intent intent = getCameraIntent();
        if (intent == SECURE_CAMERA_INTENT &&
                !mPreviewInflater.wouldLaunchResolverActivity(intent)) {
            mContext.startActivityAsUser(intent, UserHandle.CURRENT);
        } else {
            mActivityStarter.startActivity(intent);
        }
    }

    public void launchPhone() {
        mActivityStarter.startActivity(PHONE_INTENT);
    }


    @Override
    protected void onVisibilityChanged(View changedView, int visibility) {
        super.onVisibilityChanged(changedView, visibility);
        if (changedView == this && visibility == VISIBLE) {
            updateLockIcon();
            updateCameraVisibility();
        }
    }

    private void updateLockIcon() {
        if (getVisibility() != VISIBLE) {
            return;
        }
        // TODO: Real icon for facelock.
        int iconRes = mFaceUnlockRunning ? R.drawable.ic_account_circle
                : mUnlockMethodCache.isMethodInsecure() ? R.drawable.ic_lock_open_24dp
                : R.drawable.ic_lock_24dp;
        mLockIcon.setImageResource(iconRes);
        boolean trustManaged = mUnlockMethodCache.isTrustManaged();
        mLockIcon.setBackgroundResource(trustManaged && !mFaceUnlockRunning
                ? R.drawable.trust_circle : 0);
        mLockIcon.setClickable(trustManaged);
    }

    public KeyguardAffordanceView getPhoneView() {
        return mPhoneImageView;
    }

    public KeyguardAffordanceView getCameraView() {
        return mCameraImageView;
    }

    public View getPhonePreview() {
        return mPhonePreview;
    }

    public View getCameraPreview() {
        return mCameraPreview;
    }

    public KeyguardAffordanceView getLockIcon() {
        return mLockIcon;
    }

    public View getIndicationView() {
        return mIndicationText;
    }

    @Override
    public boolean hasOverlappingRendering() {
        return false;
    }

    @Override
    public void onMethodSecureChanged(boolean methodSecure) {
        updateLockIcon();
        updateCameraVisibility();
    }

    private void inflatePreviews() {
        mPhonePreview = mPreviewInflater.inflatePreview(PHONE_INTENT);
        mCameraPreview = mPreviewInflater.inflatePreview(getCameraIntent());
        if (mPhonePreview != null) {
            mPreviewContainer.addView(mPhonePreview);
            mPhonePreview.setVisibility(View.INVISIBLE);
        }
        if (mCameraPreview != null) {
            mPreviewContainer.addView(mCameraPreview);
            mCameraPreview.setVisibility(View.INVISIBLE);
        }
    }

    private final BroadcastReceiver mDevicePolicyReceiver = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            post(new Runnable() {
                @Override
                public void run() {
                    updateCameraVisibility();
                }
            });
        }
    };

    private final KeyguardUpdateMonitorCallback mUpdateMonitorCallback =
            new KeyguardUpdateMonitorCallback() {
        @Override
        public void onUserSwitchComplete(int userId) {
            updateCameraVisibility();
        }

        @Override
        public void onFaceUnlockStateChanged(boolean running) {
            mFaceUnlockRunning = running;
            updateLockIcon();
        }
    };

    public void setKeyguardIndicationController(
            KeyguardIndicationController keyguardIndicationController) {
        mIndicationController = keyguardIndicationController;
    }
}