/*
 * 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.settings.applications;

import android.app.ActivityManager;
import android.app.ActivityManager.RunningServiceInfo;
import android.app.AlertDialog;
import android.app.admin.DevicePolicyManager;
import android.content.ComponentName;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.content.pm.ServiceInfo;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.os.Process;
import android.preference.PreferenceCategory;
import android.text.format.Formatter;
import android.util.ArrayMap;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import com.android.internal.logging.MetricsLogger;
import com.android.settings.AppHeader;
import com.android.settings.CancellablePreference;
import com.android.settings.CancellablePreference.OnCancelListener;
import com.android.settings.R;
import com.android.settings.SettingsPreferenceFragment;
import com.android.settings.applications.ProcStatsEntry.Service;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;

public class ProcessStatsDetail extends SettingsPreferenceFragment
        implements Button.OnClickListener {

    private static final String TAG = "ProcessStatsDetail";

    public static final int ACTION_FORCE_STOP = 1;

    public static final String EXTRA_PACKAGE_ENTRY = "package_entry";
    public static final String EXTRA_USE_USS = "use_uss";
    public static final String EXTRA_WEIGHT_TO_RAM = "weight_to_ram";
    public static final String EXTRA_TOTAL_TIME = "total_time";
    public static final String EXTRA_MAX_MEMORY_USAGE = "max_memory_usage";
    public static final String EXTRA_TOTAL_SCALE = "total_scale";

    private static final String KEY_DETAILS_HEADER = "details_header";

    private final ArrayMap<ComponentName, CancellablePreference> mServiceMap = new ArrayMap<>();

    private PackageManager mPm;
    private DevicePolicyManager mDpm;

    private ProcStatsPackageEntry mApp;
    private boolean mUseUss;
    private double mWeightToRam;
    private long mTotalTime;
    private long mOnePercentTime;

    private Button mForceStopButton;
    private Button mReportButton;

    private LinearColorBar mColorBar;

    private float mMaxMemoryUsage;

    private double mTotalScale;

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        mPm = getActivity().getPackageManager();
        mDpm = (DevicePolicyManager)getActivity().getSystemService(Context.DEVICE_POLICY_SERVICE);
        final Bundle args = getArguments();
        mApp = args.getParcelable(EXTRA_PACKAGE_ENTRY);
        mApp.retrieveUiData(getActivity(), mPm);
        mUseUss = args.getBoolean(EXTRA_USE_USS);
        mWeightToRam = args.getDouble(EXTRA_WEIGHT_TO_RAM);
        mTotalTime = args.getLong(EXTRA_TOTAL_TIME);
        mMaxMemoryUsage = args.getFloat(EXTRA_MAX_MEMORY_USAGE);
        mTotalScale = args.getDouble(EXTRA_TOTAL_SCALE);
        mOnePercentTime = mTotalTime/100;

        mServiceMap.clear();
        createDetails();
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        AppHeader.createAppHeader(getActivity(),
                mApp.mUiTargetApp != null ? mApp.mUiTargetApp.loadIcon(mPm) : new ColorDrawable(0),
                mApp.mUiLabel, null);
    }

    @Override
    protected int getMetricsCategory() {
        return MetricsLogger.APPLICATIONS_PROCESS_STATS_DETAIL;
    }

    @Override
    public void onResume() {
        super.onResume();
        checkForceStop();

        updateRunningServices();
    }

    private void updateRunningServices() {
        ActivityManager activityManager = (ActivityManager)
                getActivity().getSystemService(Context.ACTIVITY_SERVICE);
        List<RunningServiceInfo> runningServices =
                activityManager.getRunningServices(Integer.MAX_VALUE);

        // Set all services as not running, then turn back on the ones we find.
        int N = mServiceMap.size();
        for (int i = 0; i < N; i++) {
            mServiceMap.valueAt(i).setCancellable(false);
        }

        N = runningServices.size();
        for (int i = 0; i < N; i++) {
            RunningServiceInfo runningService = runningServices.get(i);
            if (!runningService.started && runningService.clientLabel == 0) {
                continue;
            }
            if ((runningService.flags & RunningServiceInfo.FLAG_PERSISTENT_PROCESS) != 0) {
                continue;
            }
            final ComponentName service = runningService.service;
            CancellablePreference pref = mServiceMap.get(service);
            if (pref != null) {
                pref.setOnCancelListener(new OnCancelListener() {
                    @Override
                    public void onCancel(CancellablePreference preference) {
                        stopService(service.getPackageName(), service.getClassName());
                    }
                });
                pref.setCancellable(true);
            }
        }
    }

    private void createDetails() {
        addPreferencesFromResource(R.xml.app_memory_settings);

        fillProcessesSection();

        LayoutPreference headerLayout = (LayoutPreference) findPreference(KEY_DETAILS_HEADER);

        TextView avgUsed = (TextView) headerLayout.findViewById(R.id.memory_avg);
        TextView maxUsed = (TextView) headerLayout.findViewById(R.id.memory_max);
        avgUsed.setText(getString(R.string.memory_avg_desc,
                Formatter.formatShortFileSize(getActivity(),
                        (long) (Math.max(mApp.mBgWeight, mApp.mRunWeight) * mWeightToRam))));
        maxUsed.setText(getString(R.string.memory_max_desc,
                Formatter.formatShortFileSize(getActivity(),
                        (long) (Math.max(mApp.mMaxBgMem, mApp.mMaxRunMem) * 1024 * mTotalScale))));

        mForceStopButton = (Button) headerLayout.findViewById(R.id.right_button);
        mReportButton = (Button) headerLayout.findViewById(R.id.left_button);

        if (mApp.mEntries.get(0).mUid >= android.os.Process.FIRST_APPLICATION_UID) {
            mForceStopButton.setEnabled(false);
            mReportButton.setVisibility(View.INVISIBLE);

            mForceStopButton.setText(R.string.force_stop);
            mForceStopButton.setTag(ACTION_FORCE_STOP);
            mForceStopButton.setOnClickListener(this);
        } else {
            mReportButton.setVisibility(View.GONE);
            mForceStopButton.setVisibility(View.GONE);
        }

        // TODO: Find way to share this code with ProcessStatsPreference.
        boolean statsForeground = mApp.mRunWeight > mApp.mBgWeight;
        float mAvgRatio = (statsForeground ? mApp.mAvgRunMem : mApp.mAvgBgMem) / mMaxMemoryUsage;
        float mMaxRatio = (statsForeground ? mApp.mMaxRunMem : mApp.mMaxBgMem) / mMaxMemoryUsage
                - mAvgRatio;
        float mRemainingRatio = 1 - mAvgRatio - mMaxRatio;
        mColorBar = (LinearColorBar) headerLayout.findViewById(R.id.color_bar);
        Context context = getActivity();
        mColorBar.setColors(context.getColor(R.color.memory_avg_use),
                context.getColor(R.color.memory_max_use),
                context.getColor(R.color.memory_remaining));
        mColorBar.setRatios(mAvgRatio, mMaxRatio, mRemainingRatio);
    }

    public void onClick(View v) {
        doAction((Integer) v.getTag());
    }

    private void doAction(int action) {
        switch (action) {
            case ACTION_FORCE_STOP:
                killProcesses();
                break;
        }
    }

    final static Comparator<ProcStatsEntry> sEntryCompare = new Comparator<ProcStatsEntry>() {
        @Override
        public int compare(ProcStatsEntry lhs, ProcStatsEntry rhs) {
            if (lhs.mRunWeight < rhs.mRunWeight) {
                return 1;
            } else if (lhs.mRunWeight > rhs.mRunWeight) {
                return -1;
            }
            return 0;
        }
    };

    private void fillProcessesSection() {
        final ArrayList<ProcStatsEntry> entries = new ArrayList<>();
        for (int ie = 0; ie < mApp.mEntries.size(); ie++) {
            ProcStatsEntry entry = mApp.mEntries.get(ie);
            if (entry.mPackage.equals("os")) {
                entry.mLabel = entry.mName;
            } else {
                if (mApp.mEntries.size() > 1) {
                    entry.mLabel = getString(R.string.process_format, (ie + 1));
                } else {
                    entry.mLabel = getString(R.string.process);
                }
            }
            entries.add(entry);
        }
        Collections.sort(entries, sEntryCompare);
        for (int ie = 0; ie < entries.size(); ie++) {
            ProcStatsEntry entry = entries.get(ie);
            PreferenceCategory processPref = new PreferenceCategory(getActivity());
            processPref.setLayoutResource(R.layout.process_preference_category);
            processPref.setTitle(entry.mLabel);

            long memoryUse = Math.max((long)(entry.mRunWeight * mWeightToRam),
                    (long)(entry.mBgWeight * mWeightToRam));
            String memoryString = Formatter.formatShortFileSize(getActivity(), memoryUse);
            CharSequence frequency = ProcStatsPackageEntry.getFrequency(entry.mRunDuration
                    / (float)mTotalTime, getActivity());
            processPref.setSummary(
                    getString(R.string.memory_use_running_format, memoryString, frequency));
            getPreferenceScreen().addPreference(processPref);
            fillServicesSection(entry, processPref);
        }
    }

    final static Comparator<ProcStatsEntry.Service> sServiceCompare
            = new Comparator<ProcStatsEntry.Service>() {
        @Override
        public int compare(ProcStatsEntry.Service lhs, ProcStatsEntry.Service rhs) {
            if (lhs.mDuration < rhs.mDuration) {
                return 1;
            } else if (lhs.mDuration > rhs.mDuration) {
                return -1;
            }
            return 0;
        }
    };

    final static Comparator<PkgService> sServicePkgCompare = new Comparator<PkgService>() {
        @Override
        public int compare(PkgService lhs, PkgService rhs) {
            if (lhs.mDuration < rhs.mDuration) {
                return 1;
            } else if (lhs.mDuration > rhs.mDuration) {
                return -1;
            }
            return 0;
        }
    };

    static class PkgService {
        final ArrayList<ProcStatsEntry.Service> mServices = new ArrayList<>();
        long mDuration;
    }

    private void fillServicesSection(ProcStatsEntry entry, PreferenceCategory processPref) {
        final HashMap<String, PkgService> pkgServices = new HashMap<>();
        final ArrayList<PkgService> pkgList = new ArrayList<>();
        for (int ip = 0; ip < entry.mServices.size(); ip++) {
            String pkg = entry.mServices.keyAt(ip);
            PkgService psvc = null;
            ArrayList<ProcStatsEntry.Service> services = entry.mServices.valueAt(ip);
            for (int is=services.size()-1; is>=0; is--) {
                ProcStatsEntry.Service pent = services.get(is);
                if (pent.mDuration >= mOnePercentTime) {
                    if (psvc == null) {
                        psvc = pkgServices.get(pkg);
                        if (psvc == null) {
                            psvc = new PkgService();
                            pkgServices.put(pkg, psvc);
                            pkgList.add(psvc);
                        }
                    }
                    psvc.mServices.add(pent);
                    psvc.mDuration += pent.mDuration;
                }
            }
        }
        Collections.sort(pkgList, sServicePkgCompare);
        for (int ip = 0; ip < pkgList.size(); ip++) {
            ArrayList<ProcStatsEntry.Service> services = pkgList.get(ip).mServices;
            Collections.sort(services, sServiceCompare);
            for (int is=0; is<services.size(); is++) {
                final ProcStatsEntry.Service service = services.get(is);
                CharSequence label = getLabel(service);
                CancellablePreference servicePref = new CancellablePreference(getActivity());
                servicePref.setSelectable(false);
                servicePref.setTitle(label);
                servicePref.setSummary(ProcStatsPackageEntry.getFrequency(
                        service.mDuration / (float) mTotalTime, getActivity()));
                processPref.addPreference(servicePref);
                mServiceMap.put(new ComponentName(service.mPackage, service.mName), servicePref);
            }
        }
    }

    private CharSequence getLabel(Service service) {
        // Try to get the service label, on the off chance that one exists.
        try {
            ServiceInfo serviceInfo = getPackageManager().getServiceInfo(
                    new ComponentName(service.mPackage, service.mName), 0);
            if (serviceInfo.labelRes != 0) {
                return serviceInfo.loadLabel(getPackageManager());
            }
        } catch (NameNotFoundException e) {
        }
        String label = service.mName;
        int tail = label.lastIndexOf('.');
        if (tail >= 0 && tail < (label.length()-1)) {
            label = label.substring(tail+1);
        }
        return label;
    }

    private void stopService(String pkg, String name) {
        try {
            ApplicationInfo appInfo = getActivity().getPackageManager().getApplicationInfo(pkg, 0);
            if ((appInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0) {
                showStopServiceDialog(pkg, name);
                return;
            }
        } catch (NameNotFoundException e) {
            Log.e(TAG, "Can't find app " + pkg, e);
            return;
        }
        doStopService(pkg, name);
    }

    private void showStopServiceDialog(final String pkg, final String name) {
        new AlertDialog.Builder(getActivity())
                .setTitle(R.string.runningservicedetails_stop_dlg_title)
                .setMessage(R.string.runningservicedetails_stop_dlg_text)
                .setPositiveButton(R.string.dlg_ok, new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        doStopService(pkg, name);
                    }
                })
                .setNegativeButton(R.string.dlg_cancel, null)
                .show();
    }

    private void doStopService(String pkg, String name) {
        getActivity().stopService(new Intent().setClassName(pkg, name));
        updateRunningServices();
    }

    private void killProcesses() {
        ActivityManager am = (ActivityManager)getActivity().getSystemService(
                Context.ACTIVITY_SERVICE);
        for (int i=0; i< mApp.mEntries.size(); i++) {
            ProcStatsEntry ent = mApp.mEntries.get(i);
            for (int j=0; j<ent.mPackages.size(); j++) {
                am.forceStopPackage(ent.mPackages.get(j));
            }
        }
        checkForceStop();
    }

    private void checkForceStop() {
        if (mApp.mEntries.get(0).mUid < Process.FIRST_APPLICATION_UID) {
            mForceStopButton.setEnabled(false);
            return;
        }
        boolean isStarted = false;
        for (int i=0; i< mApp.mEntries.size(); i++) {
            ProcStatsEntry ent = mApp.mEntries.get(i);
            for (int j=0; j<ent.mPackages.size(); j++) {
                String pkg = ent.mPackages.get(j);
                if (mDpm.packageHasActiveAdmins(pkg)) {
                    mForceStopButton.setEnabled(false);
                    return;
                }
                try {
                    ApplicationInfo info = mPm.getApplicationInfo(pkg, 0);
                    if ((info.flags&ApplicationInfo.FLAG_STOPPED) == 0) {
                        isStarted = true;
                    }
                } catch (PackageManager.NameNotFoundException e) {
                }
            }
        }
        if (isStarted) {
            mForceStopButton.setEnabled(true);
        }
    }
}