/*
 * Copyright (C) 2018 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.fuelgauge.batterytip;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

import androidx.annotation.IntDef;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

/** Database controls the anomaly logging(e.g. packageName, anomalyType and time) */
public class AnomalyDatabaseHelper extends SQLiteOpenHelper {
    private static final String TAG = "BatteryDatabaseHelper";

    private static final String DATABASE_NAME = "battery_settings.db";
    private static final int DATABASE_VERSION = 5;

    @Retention(RetentionPolicy.SOURCE)
    @IntDef({State.NEW, State.HANDLED, State.AUTO_HANDLED})
    public @interface State {
        int NEW = 0;
        int HANDLED = 1;
        int AUTO_HANDLED = 2;
    }

    @Retention(RetentionPolicy.SOURCE)
    @IntDef({ActionType.RESTRICTION})
    public @interface ActionType {
        int RESTRICTION = 0;
    }

    public interface Tables {
        String TABLE_ANOMALY = "anomaly";
        String TABLE_ACTION = "action";
    }

    public interface AnomalyColumns {
        /** The package name of the anomaly app */
        String PACKAGE_NAME = "package_name";

        /** The uid of the anomaly app */
        String UID = "uid";

        /**
         * The type of the anomaly app
         *
         * @see StatsManagerConfig.AnomalyType
         */
        String ANOMALY_TYPE = "anomaly_type";

        /**
         * The state of the anomaly app
         *
         * @see State
         */
        String ANOMALY_STATE = "anomaly_state";

        /** The time when anomaly happens */
        String TIME_STAMP_MS = "time_stamp_ms";
    }

    private static final String CREATE_ANOMALY_TABLE =
            "CREATE TABLE "
                    + Tables.TABLE_ANOMALY
                    + "("
                    + AnomalyColumns.UID
                    + " INTEGER NOT NULL, "
                    + AnomalyColumns.PACKAGE_NAME
                    + " TEXT, "
                    + AnomalyColumns.ANOMALY_TYPE
                    + " INTEGER NOT NULL, "
                    + AnomalyColumns.ANOMALY_STATE
                    + " INTEGER NOT NULL, "
                    + AnomalyColumns.TIME_STAMP_MS
                    + " INTEGER NOT NULL, "
                    + " PRIMARY KEY ("
                    + AnomalyColumns.UID
                    + ","
                    + AnomalyColumns.ANOMALY_TYPE
                    + ","
                    + AnomalyColumns.ANOMALY_STATE
                    + ","
                    + AnomalyColumns.TIME_STAMP_MS
                    + ")"
                    + ")";

    public interface ActionColumns {
        /** The package name of an app been performed an action */
        String PACKAGE_NAME = "package_name";

        /** The uid of an app been performed an action */
        String UID = "uid";

        /**
         * The type of user action
         *
         * @see ActionType
         */
        String ACTION_TYPE = "action_type";

        /** The time when action been performed */
        String TIME_STAMP_MS = "time_stamp_ms";
    }

    private static final String CREATE_ACTION_TABLE =
            "CREATE TABLE "
                    + Tables.TABLE_ACTION
                    + "("
                    + ActionColumns.UID
                    + " INTEGER NOT NULL, "
                    + ActionColumns.PACKAGE_NAME
                    + " TEXT, "
                    + ActionColumns.ACTION_TYPE
                    + " INTEGER NOT NULL, "
                    + ActionColumns.TIME_STAMP_MS
                    + " INTEGER NOT NULL, "
                    + " PRIMARY KEY ("
                    + ActionColumns.ACTION_TYPE
                    + ","
                    + ActionColumns.UID
                    + ","
                    + ActionColumns.PACKAGE_NAME
                    + ")"
                    + ")";

    private static AnomalyDatabaseHelper sSingleton;

    public static synchronized AnomalyDatabaseHelper getInstance(Context context) {
        if (sSingleton == null) {
            sSingleton = new AnomalyDatabaseHelper(context.getApplicationContext());
        }
        return sSingleton;
    }

    private AnomalyDatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        bootstrapDB(db);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        if (oldVersion < DATABASE_VERSION) {
            Log.w(
                    TAG,
                    "Detected schema version '"
                            + oldVersion
                            + "'. "
                            + "Index needs to be rebuilt for schema version '"
                            + newVersion
                            + "'.");
            // We need to drop the tables and recreate them
            reconstruct(db);
        }
    }

    @Override
    public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        Log.w(
                TAG,
                "Detected schema version '"
                        + oldVersion
                        + "'. "
                        + "Index needs to be rebuilt for schema version '"
                        + newVersion
                        + "'.");
        // We need to drop the tables and recreate them
        reconstruct(db);
    }

    public void reconstruct(SQLiteDatabase db) {
        dropTables(db);
        bootstrapDB(db);
    }

    private void bootstrapDB(SQLiteDatabase db) {
        db.execSQL(CREATE_ANOMALY_TABLE);
        db.execSQL(CREATE_ACTION_TABLE);
        Log.i(TAG, "Bootstrapped database");
    }

    private void dropTables(SQLiteDatabase db) {
        db.execSQL("DROP TABLE IF EXISTS " + Tables.TABLE_ANOMALY);
        db.execSQL("DROP TABLE IF EXISTS " + Tables.TABLE_ACTION);
    }
}