content: /*
   * Copyright (C) 2014 Hari Krishna Dulipudi
   * 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 dev.dworks.apps.anexplorer.provider;
  
  import android.content.ContentProvider;
  import android.content.ContentResolver;
  import android.content.ContentValues;
  import android.content.Context;
  import android.content.Intent;
  import android.content.UriMatcher;
  import android.content.pm.ProviderInfo;
  import android.database.Cursor;
  import android.database.sqlite.SQLiteDatabase;
  import android.database.sqlite.SQLiteOpenHelper;
  import android.net.Uri;
  import android.os.Bundle;
  import androidx.collection.ArraySet;
  import android.text.format.DateUtils;
  import android.util.Log;
  
  import java.io.IOException;
  import java.util.List;
  
  import dev.dworks.apps.anexplorer.BuildConfig;
  import dev.dworks.apps.anexplorer.libcore.io.IoUtils;
  import dev.dworks.apps.anexplorer.libcore.util.Predicate;
  import dev.dworks.apps.anexplorer.model.DocumentStack;
  import dev.dworks.apps.anexplorer.model.DocumentsContract;
  import dev.dworks.apps.anexplorer.model.DocumentsContract.Document;
  import dev.dworks.apps.anexplorer.model.DocumentsContract.Root;
  import dev.dworks.apps.anexplorer.model.DurableUtils;
  
  import static dev.dworks.apps.anexplorer.model.DocumentInfo.getCursorString;
  
  public class RecentsProvider extends ContentProvider {
      private static final String TAG = "RecentsProvider";
  
      private static final long MAX_HISTORY_IN_MILLIS = 45 * DateUtils.DAY_IN_MILLIS;
  
      public static final String AUTHORITY = BuildConfig.APPLICATION_ID + ".recents";
  
      private static final UriMatcher sMatcher = new UriMatcher(UriMatcher.NO_MATCH);
  
      private static final int URI_RECENT = 1;
      private static final int URI_STATE = 2;
      private static final int URI_RESUME = 3;
  
      public static final String METHOD_PURGE = "purge";
      public static final String METHOD_PURGE_PACKAGE = "purgePackage";
  
      static {
          sMatcher.addURI(AUTHORITY, "recent", URI_RECENT);
          // state/authority/rootId/docId
          sMatcher.addURI(AUTHORITY, "state/*/*/*", URI_STATE);
          // resume/packageName
          sMatcher.addURI(AUTHORITY, "resume/*", URI_RESUME);
      }
  
      public static final String TABLE_RECENT = "recent";
      public static final String TABLE_STATE = "state";
      public static final String TABLE_RESUME = "resume";
  
      public static class RecentColumns {
          public static final String KEY = "key";
          public static final String STACK = "stack";
          public static final String TIMESTAMP = "timestamp";
      }
  
      public static class StateColumns {
          public static final String AUTHORITY = "authority";
          public static final String ROOT_ID = Root.COLUMN_ROOT_ID;
          public static final String DOCUMENT_ID = Document.COLUMN_DOCUMENT_ID;
          public static final String MODE = "mode";
          public static final String SORT_ORDER = "sortOrder";
      }
  
      public static class ResumeColumns {
          public static final String PACKAGE_NAME = "package_name";
          public static final String STACK = "stack";
          public static final String TIMESTAMP = "timestamp";
          public static final String EXTERNAL = "external";
      }
  
      public static Uri buildRecent() {
          return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT)
                  .authority(AUTHORITY).appendPath("recent").build();
      }
  
      public static Uri buildState(String authority, String rootId, String documentId) {
          return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT).authority(AUTHORITY)
                  .appendPath("state").appendPath(authority).appendPath(rootId).appendPath(documentId)
                  .build();
      }
  
      public static Uri buildResume(String packageName) {
          return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT)
                  .authority(AUTHORITY).appendPath("resume").appendPath(packageName).build();
      }
  
      private DatabaseHelper mHelper;
  
      @SuppressWarnings("unused")
      private static class DatabaseHelper extends SQLiteOpenHelper {
          private static final String DB_NAME = "recents.db";
  
          private static final int VERSION_INIT = 1;
          private static final int VERSION_AS_BLOB = 3;
          private static final int VERSION_ADD_EXTERNAL = 4;
          private static final int VERSION_ADD_RECENT_KEY = 5;
  
          public DatabaseHelper(Context context) {
              super(context, DB_NAME, null, VERSION_ADD_RECENT_KEY);
          }
  
          @Override
          public void onCreate(SQLiteDatabase db) {
  
              db.execSQL("CREATE TABLE " + TABLE_RECENT + " (" +
                      RecentColumns.KEY + " TEXT PRIMARY KEY ON CONFLICT REPLACE," +
                      RecentColumns.STACK + " BLOB DEFAULT NULL," +
                      RecentColumns.TIMESTAMP + " INTEGER" +
                      ")");
  
              db.execSQL("CREATE TABLE " + TABLE_STATE + " (" +
                      StateColumns.AUTHORITY + " TEXT," +
                      StateColumns.ROOT_ID + " TEXT," +
                      StateColumns.DOCUMENT_ID + " TEXT," +
                      StateColumns.MODE + " INTEGER," +
                      StateColumns.SORT_ORDER + " INTEGER," +
                      "PRIMARY KEY (" + StateColumns.AUTHORITY + ", " + StateColumns.ROOT_ID + ", "
                      + StateColumns.DOCUMENT_ID + ")" +
                      ")");
  
              db.execSQL("CREATE TABLE " + TABLE_RESUME + " (" +
                      ResumeColumns.PACKAGE_NAME + " TEXT NOT NULL PRIMARY KEY," +
                      ResumeColumns.STACK + " BLOB DEFAULT NULL," +
                      ResumeColumns.TIMESTAMP + " INTEGER," +
                      ResumeColumns.EXTERNAL + " INTEGER NOT NULL DEFAULT 0" +
                      ")");
          }
  
          @Override
          public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
              Log.w(TAG, "Upgrading database; wiping app data");
              db.execSQL("DROP TABLE IF EXISTS " + TABLE_RECENT);
              db.execSQL("DROP TABLE IF EXISTS " + TABLE_STATE);
              db.execSQL("DROP TABLE IF EXISTS " + TABLE_RESUME);
              onCreate(db);
          }
      }
  
      @Override
      public boolean onCreate() {
          mHelper = new DatabaseHelper(getContext());
          return true;
      }
  
      @Override
      public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
              String sortOrder) {
          final SQLiteDatabase db = mHelper.getReadableDatabase();
          switch (sMatcher.match(uri)) {
              case URI_RECENT:
                  final long cutoff = System.currentTimeMillis() - MAX_HISTORY_IN_MILLIS;
                  return db.query(TABLE_RECENT, projection, RecentColumns.TIMESTAMP + ">" + cutoff,
                          null, null, null, sortOrder);
              case URI_STATE:
                  final String authority = uri.getPathSegments().get(1);
                  final String rootId = uri.getPathSegments().get(2);
                  final String documentId = uri.getPathSegments().get(3);
                  return db.query(TABLE_STATE, projection, StateColumns.AUTHORITY + "=? AND "
                          + StateColumns.ROOT_ID + "=? AND " + StateColumns.DOCUMENT_ID + "=?",
                          new String[] { authority, rootId, documentId }, null, null, sortOrder);
              case URI_RESUME:
                  final String packageName = uri.getPathSegments().get(1);
                  return db.query(TABLE_RESUME, projection, ResumeColumns.PACKAGE_NAME + "=?",
                          new String[] { packageName }, null, null, sortOrder);
              default:
                  return null;
                  //throw new UnsupportedOperationException("Unsupported Uri " + uri);
          }
      }
  
      @Override
      public String getType(Uri uri) {
          return null;
      }
  
      @Override
      public Uri insert(Uri uri, ContentValues values) {
          final SQLiteDatabase db = mHelper.getWritableDatabase();
          final ContentValues key = new ContentValues();
          switch (sMatcher.match(uri)) {
              case URI_RECENT:
                  values.put(RecentColumns.TIMESTAMP, System.currentTimeMillis());
                  db.insert(TABLE_RECENT, null, values);
                  final long cutoff = System.currentTimeMillis() - MAX_HISTORY_IN_MILLIS;
                  db.delete(TABLE_RECENT, RecentColumns.TIMESTAMP + "<" + cutoff, null);
                  return uri;
              case URI_STATE:
                  final String authority = uri.getPathSegments().get(1);
                  final String rootId = uri.getPathSegments().get(2);
                  final String documentId = uri.getPathSegments().get(3);
  
                  key.put(StateColumns.AUTHORITY, authority);
                  key.put(StateColumns.ROOT_ID, rootId);
                  key.put(StateColumns.DOCUMENT_ID, documentId);
  
                  // Ensure that row exists, then update with changed values
                  db.insertWithOnConflict(TABLE_STATE, null, key, SQLiteDatabase.CONFLICT_IGNORE);
                  db.update(TABLE_STATE, values, StateColumns.AUTHORITY + "=? AND "
                          + StateColumns.ROOT_ID + "=? AND " + StateColumns.DOCUMENT_ID + "=?",
                          new String[] { authority, rootId, documentId });
  
                  return uri;
              case URI_RESUME:
                  values.put(ResumeColumns.TIMESTAMP, System.currentTimeMillis());
  
                  final String packageName = uri.getPathSegments().get(1);
                  key.put(ResumeColumns.PACKAGE_NAME, packageName);
  
                  // Ensure that row exists, then update with changed values
                  db.insertWithOnConflict(TABLE_RESUME, null, key, SQLiteDatabase.CONFLICT_IGNORE);
                  db.update(TABLE_RESUME, values, ResumeColumns.PACKAGE_NAME + "=?",
                          new String[] { packageName });
                  return uri;
              default:
                  throw new UnsupportedOperationException("Unsupported Uri " + uri);
          }
      }
  
      @Override
      public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
          throw new UnsupportedOperationException("Unsupported Uri " + uri);
      }
  
      @Override
      public int delete(Uri uri, String selection, String[] selectionArgs) {
          throw new UnsupportedOperationException("Unsupported Uri " + uri);
      }
  
      @Override
      public Bundle call(String method, String arg, Bundle extras) {
          if (METHOD_PURGE.equals(method)) {
              // Purge references to unknown authorities
              final ArraySet<String> knownAuth = new ArraySet<>();
              List<ProviderInfo> providers = getContext().getPackageManager()
              	    .queryContentProviders(getContext().getPackageName(), getContext().getApplicationInfo().uid, 0);
              for (ProviderInfo providerInfo : providers) {
              	knownAuth.add(providerInfo.authority);
  			}
  
              purgeByAuthority(new Predicate<String>() {
                  @Override
                  public boolean apply(String authority) {
                      // Purge unknown authorities
                      return !knownAuth.contains(authority);
                  }
              });
  
              return null;
  
          } else if (METHOD_PURGE_PACKAGE.equals(method)) {
              // Purge references to authorities in given package
              final Intent intent = new Intent(DocumentsContract.PROVIDER_INTERFACE);
              intent.setPackage(arg);
              final ArraySet<String> packageAuth = new ArraySet<>();
              List<ProviderInfo> providers = getContext().getPackageManager()
              	    .queryContentProviders(getContext().getPackageName(), getContext().getApplicationInfo().uid, 0);
              for (ProviderInfo providerInfo : providers) {
              	packageAuth.add(providerInfo.authority);
  			}
              if (!packageAuth.isEmpty()) {
                  purgeByAuthority(new Predicate<String>() {
                      @Override
                      public boolean apply(String authority) {
                          // Purge authority matches
                          return packageAuth.contains(authority);
                      }
                  });
              }
  
              return null;
  
          } else {
              return super.call(method, arg, extras);
          }
      }
  
      /**
       * Purge all internal data whose authority matches the given
       * {@link Predicate}.
       */
      private void purgeByAuthority(Predicate<String> predicate) {
          final SQLiteDatabase db = mHelper.getWritableDatabase();
          final DocumentStack stack = new DocumentStack();
  
          Cursor cursor = db.query(TABLE_RECENT, null, null, null, null, null, null);
          try {
              while (cursor.moveToNext()) {
                  try {
                      final byte[] rawStack = cursor.getBlob(
                              cursor.getColumnIndex(RecentColumns.STACK));
                      DurableUtils.readFromArray(rawStack, stack);
  
                      if (stack.root != null && predicate.apply(stack.root.authority)) {
                          final String key = getCursorString(cursor, RecentColumns.KEY);
                          db.delete(TABLE_RECENT, RecentColumns.KEY + "=?", new String[] { key });
                      }
                  } catch (IOException ignored) {
                  }
              }
          } finally {
              IoUtils.closeQuietly(cursor);
          }
  
          cursor = db.query(TABLE_STATE, new String[] {
                  StateColumns.AUTHORITY }, null, null, StateColumns.AUTHORITY, null, null);
          try {
              while (cursor.moveToNext()) {
                  final String authority = getCursorString(cursor, StateColumns.AUTHORITY);
                  if (predicate.apply(authority)) {
                      db.delete(TABLE_STATE, StateColumns.AUTHORITY + "=?", new String[] {
                              authority });
                      Log.d(TAG, "Purged state for " + authority);
                  }
              }
          } finally {
              IoUtils.closeQuietly(cursor);
          }
  
          cursor = db.query(TABLE_RESUME, null, null, null, null, null, null);
          try {
              while (cursor.moveToNext()) {
                  try {
                      final byte[] rawStack = cursor.getBlob(
                              cursor.getColumnIndex(ResumeColumns.STACK));
                      DurableUtils.readFromArray(rawStack, stack);
  
                      if (stack.root != null && predicate.apply(stack.root.authority)) {
                          final String packageName = getCursorString(
                                  cursor, ResumeColumns.PACKAGE_NAME);
                          db.delete(TABLE_RESUME, ResumeColumns.PACKAGE_NAME + "=?",
                                  new String[] { packageName });
                      }
                  } catch (IOException ignored) {
                  }
              }
          } finally {
              IoUtils.closeQuietly(cursor);
          }
      }
  }