/*
 * Copyright 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.server.telecom;

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.TaskStackBuilder;
import android.content.AsyncQueryHandler;
import android.content.ContentValues;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.UserHandle;
import android.provider.CallLog;
import android.provider.CallLog.Calls;
import android.telecom.CallState;
import android.telecom.DisconnectCause;
import android.telecom.PhoneAccount;
import android.telephony.PhoneNumberUtils;
import android.text.BidiFormatter;
import android.text.TextDirectionHeuristics;
import android.text.TextUtils;

// TODO: Needed for move to system service: import com.android.internal.R;

/**
 * Creates a notification for calls that the user missed (neither answered nor rejected).
 * TODO: Make TelephonyManager.clearMissedCalls call into this class.
 */
class MissedCallNotifier extends CallsManagerListenerBase {

    private static final String[] CALL_LOG_PROJECTION = new String[] {
        Calls._ID,
        Calls.NUMBER,
        Calls.NUMBER_PRESENTATION,
        Calls.DATE,
        Calls.DURATION,
        Calls.TYPE,
    };

    private static final int CALL_LOG_COLUMN_ID = 0;
    private static final int CALL_LOG_COLUMN_NUMBER = 1;
    private static final int CALL_LOG_COLUMN_NUMBER_PRESENTATION = 2;
    private static final int CALL_LOG_COLUMN_DATE = 3;
    private static final int CALL_LOG_COLUMN_DURATION = 4;
    private static final int CALL_LOG_COLUMN_TYPE = 5;

    private static final int MISSED_CALL_NOTIFICATION_ID = 1;

    private final Context mContext;
    private final NotificationManager mNotificationManager;

    // Used to track the number of missed calls.
    private int mMissedCallCount = 0;

    MissedCallNotifier(Context context) {
        mContext = context;
        mNotificationManager =
                (NotificationManager) mContext.getSystemService(Context.NOTIFICATION_SERVICE);

        updateOnStartup();
    }

    /** {@inheritDoc} */
    @Override
    public void onCallStateChanged(Call call, int oldState, int newState) {
        if (oldState == CallState.RINGING && newState == CallState.DISCONNECTED &&
                call.getDisconnectCause().getCode() == DisconnectCause.MISSED) {
            showMissedCallNotification(call);
        }
    }

    /** Clears missed call notification and marks the call log's missed calls as read. */
    void clearMissedCalls() {
        AsyncTask.execute(new Runnable() {
            @Override
            public void run() {
                // Clear the list of new missed calls from the call log.
                ContentValues values = new ContentValues();
                values.put(Calls.NEW, 0);
                values.put(Calls.IS_READ, 1);
                StringBuilder where = new StringBuilder();
                where.append(Calls.NEW);
                where.append(" = 1 AND ");
                where.append(Calls.TYPE);
                where.append(" = ?");
                mContext.getContentResolver().update(Calls.CONTENT_URI, values, where.toString(),
                        new String[]{ Integer.toString(Calls.MISSED_TYPE) });
            }
        });
        cancelMissedCallNotification();
    }

    /**
     * Create a system notification for the missed call.
     *
     * @param call The missed call.
     */
    void showMissedCallNotification(Call call) {
        mMissedCallCount++;

        final int titleResId;
        final String expandedText;  // The text in the notification's line 1 and 2.

        // Display the first line of the notification:
        // 1 missed call: <caller name || handle>
        // More than 1 missed call: <number of calls> + "missed calls"
        if (mMissedCallCount == 1) {
            titleResId = R.string.notification_missedCallTitle;
            expandedText = getNameForCall(call);
        } else {
            titleResId = R.string.notification_missedCallsTitle;
            expandedText =
                    mContext.getString(R.string.notification_missedCallsMsg, mMissedCallCount);
        }

        // Create the notification.
        Notification.Builder builder = new Notification.Builder(mContext);
        builder.setSmallIcon(android.R.drawable.stat_notify_missed_call)
                .setColor(mContext.getResources().getColor(R.color.theme_color))
                .setWhen(call.getCreationTimeMillis())
                .setContentTitle(mContext.getText(titleResId))
                .setContentText(expandedText)
                .setContentIntent(createCallLogPendingIntent())
                .setAutoCancel(true)
                .setDeleteIntent(createClearMissedCallsPendingIntent());

        Uri handleUri = call.getHandle();
        String handle = handleUri == null ? null : handleUri.getSchemeSpecificPart();

        // Add additional actions when there is only 1 missed call, like call-back and SMS.
        if (mMissedCallCount == 1) {
            Log.d(this, "Add actions with number %s.", Log.piiHandle(handle));

            if (!TextUtils.isEmpty(handle)
                    && !TextUtils.equals(handle, mContext.getString(R.string.handle_restricted))) {
                builder.addAction(R.drawable.stat_sys_phone_call,
                        mContext.getString(R.string.notification_missedCall_call_back),
                        createCallBackPendingIntent(handleUri));

                builder.addAction(R.drawable.ic_text_holo_dark,
                        mContext.getString(R.string.notification_missedCall_message),
                        createSendSmsFromNotificationPendingIntent(handleUri));
            }

            Bitmap photoIcon = call.getPhotoIcon();
            if (photoIcon != null) {
                builder.setLargeIcon(photoIcon);
            } else {
                Drawable photo = call.getPhoto();
                if (photo != null && photo instanceof BitmapDrawable) {
                    builder.setLargeIcon(((BitmapDrawable) photo).getBitmap());
                }
            }
        } else {
            Log.d(this, "Suppress actions. handle: %s, missedCalls: %d.", Log.piiHandle(handle),
                    mMissedCallCount);
        }

        Notification notification = builder.build();
        configureLedOnNotification(notification);

        Log.i(this, "Adding missed call notification for %s.", call);
        mNotificationManager.notifyAsUser(
                null /* tag */ , MISSED_CALL_NOTIFICATION_ID, notification, UserHandle.CURRENT);
    }

    /** Cancels the "missed call" notification. */
    private void cancelMissedCallNotification() {
        // Reset the number of missed calls to 0.
        mMissedCallCount = 0;
        mNotificationManager.cancel(MISSED_CALL_NOTIFICATION_ID);
    }

    /**
     * Returns the name to use in the missed call notification.
     */
    private String getNameForCall(Call call) {
        String handle = call.getHandle() == null ? null : call.getHandle().getSchemeSpecificPart();
        String name = call.getName();

        if (!TextUtils.isEmpty(name) && TextUtils.isGraphic(name)) {
            return name;
        } else if (!TextUtils.isEmpty(handle)) {
            // A handle should always be displayed LTR using {@link BidiFormatter} regardless of the
            // content of the rest of the notification.
            // TODO: Does this apply to SIP addresses?
            BidiFormatter bidiFormatter = BidiFormatter.getInstance();
            return bidiFormatter.unicodeWrap(handle, TextDirectionHeuristics.LTR);
        } else {
            // Use "unknown" if the call is unidentifiable.
            return mContext.getString(R.string.unknown);
        }
    }

    /**
     * Creates a new pending intent that sends the user to the call log.
     *
     * @return The pending intent.
     */
    private PendingIntent createCallLogPendingIntent() {
        Intent intent = new Intent(Intent.ACTION_VIEW, null);
        intent.setType(CallLog.Calls.CONTENT_TYPE);

        TaskStackBuilder taskStackBuilder = TaskStackBuilder.create(mContext);
        taskStackBuilder.addNextIntent(intent);

        return taskStackBuilder.getPendingIntent(0, 0);
    }

    /**
     * Creates an intent to be invoked when the missed call notification is cleared.
     */
    private PendingIntent createClearMissedCallsPendingIntent() {
        return createTelecomPendingIntent(
                TelecomBroadcastReceiver.ACTION_CLEAR_MISSED_CALLS, null);
    }

    /**
     * Creates an intent to be invoked when the user opts to "call back" from the missed call
     * notification.
     *
     * @param handle The handle to call back.
     */
    private PendingIntent createCallBackPendingIntent(Uri handle) {
        return createTelecomPendingIntent(
                TelecomBroadcastReceiver.ACTION_CALL_BACK_FROM_NOTIFICATION, handle);
    }

    /**
     * Creates an intent to be invoked when the user opts to "send sms" from the missed call
     * notification.
     */
    private PendingIntent createSendSmsFromNotificationPendingIntent(Uri handle) {
        return createTelecomPendingIntent(
                TelecomBroadcastReceiver.ACTION_SEND_SMS_FROM_NOTIFICATION,
                Uri.fromParts(Constants.SCHEME_SMSTO, handle.getSchemeSpecificPart(), null));
    }

    /**
     * Creates generic pending intent from the specified parameters to be received by
     * {@link TelecomBroadcastReceiver}.
     *
     * @param action The intent action.
     * @param data The intent data.
     */
    private PendingIntent createTelecomPendingIntent(String action, Uri data) {
        Intent intent = new Intent(action, data, mContext, TelecomBroadcastReceiver.class);
        return PendingIntent.getBroadcast(mContext, 0, intent, 0);
    }

    /**
     * Configures a notification to emit the blinky notification light.
     */
    private void configureLedOnNotification(Notification notification) {
        notification.flags |= Notification.FLAG_SHOW_LIGHTS;
        notification.defaults |= Notification.DEFAULT_LIGHTS;
    }

    /**
     * Adds the missed call notification on startup if there are unread missed calls.
     */
    private void updateOnStartup() {
        Log.d(this, "updateOnStartup()...");

        // instantiate query handler
        AsyncQueryHandler queryHandler = new AsyncQueryHandler(mContext.getContentResolver()) {
            @Override
            protected void onQueryComplete(int token, Object cookie, Cursor cursor) {
                Log.d(MissedCallNotifier.this, "onQueryComplete()...");
                if (cursor != null) {
                    try {
                        while (cursor.moveToNext()) {
                            // Get data about the missed call from the cursor
                            final String handleString = cursor.getString(CALL_LOG_COLUMN_NUMBER);
                            final int presentation =
                                    cursor.getInt(CALL_LOG_COLUMN_NUMBER_PRESENTATION);
                            final long date = cursor.getLong(CALL_LOG_COLUMN_DATE);

                            final Uri handle;
                            if (presentation != Calls.PRESENTATION_ALLOWED
                                    || TextUtils.isEmpty(handleString)) {
                                handle = null;
                            } else {
                                handle = Uri.fromParts(PhoneNumberUtils.isUriNumber(handleString) ?
                                        PhoneAccount.SCHEME_SIP : PhoneAccount.SCHEME_TEL,
                                                handleString, null);
                            }

                            // Convert the data to a call object
                            Call call = new Call(mContext, null, null, null, null, null, true,
                                    false);
                            call.setDisconnectCause(new DisconnectCause(DisconnectCause.MISSED));
                            call.setState(CallState.DISCONNECTED);
                            call.setCreationTimeMillis(date);

                            // Listen for the update to the caller information before posting the
                            // notification so that we have the contact info and photo.
                            call.addListener(new Call.ListenerBase() {
                                @Override
                                public void onCallerInfoChanged(Call call) {
                                    call.removeListener(this);  // No longer need to listen to call
                                                                // changes after the contact info
                                                                // is retrieved.
                                    showMissedCallNotification(call);
                                }
                            });
                            // Set the handle here because that is what triggers the contact info
                            // query.
                            call.setHandle(handle, presentation);
                        }
                    } finally {
                        cursor.close();
                    }
                }
            }
        };

        // setup query spec, look for all Missed calls that are new.
        StringBuilder where = new StringBuilder("type=");
        where.append(Calls.MISSED_TYPE);
        where.append(" AND new=1");

        // start the query
        queryHandler.startQuery(0, null, Calls.CONTENT_URI, CALL_LOG_PROJECTION,
                where.toString(), null, Calls.DEFAULT_SORT_ORDER);
    }
}