content: /*
   * Copyright (C) 2015-2023 Emanuel Moecklin
   *
   * 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.onegravity.rteditor.effects;
  
  import android.text.Spannable;
  
  import com.onegravity.rteditor.spans.RTSpan;
  import com.onegravity.rteditor.utils.Selection;
  
  import java.lang.reflect.Array;
  import java.util.List;
  
  /**
   * Spanned.getSpans(int, int, Class) unfortunately doesn't respect the mark/point flags
   * (SPAN_EXCLUSIVE_EXCLUSIVE, SPAN_INCLUSIVE_EXCLUSIVE etc.).
   *
   * Android finds spans that precede or follow a selection (adjacent spans).
   *
   * - if the span is a point (start == end) --> every adjacent selection (cursor, range = selected text) will match:
   *   01234[]|56789     point selection after point span   --> getSpans returns span
   *   01234|[]56789     point selection before point span  --> getSpans returns span
   *   01234[]|56|789    range selection after point span   --> getSpans returns span
   *   012|34|[]56789    range selection before point span  --> getSpans returns span
   *
   * - if the span is a range (start < end) --> only point selections (cursors) will match:
   *   01[234]|56789     point selection after range span  --> getSpans returns span
   *   01234|[567]89     point selection before range span --> getSpans returns span
   *   01[234]|56|789    range selection after range span  --> getSpans returns nothing
   *   012|34|[567]89    range selection before range span --> getSpans returns nothing
   *
   * The span flags (SPAN_EXCLUSIVE_INCLUSIVE etc.) have no impact!
   *
   * (exception SPAN_EXCLUSIVE_EXCLUSIVE for point spans because those can't have a length of 0 and
   *  will be removed automatically:
   *  http://developer.android.com/reference/android/text/Spanned.html#SPAN_EXCLUSIVE_EXCLUSIVE)
   *
   * Sometimes we need to find or ignore adjacent spans depending on the span flags, the position of a
   * span, the selection (last line, empty lines...) and the type of span (character, paragraph).
   *
   * This class allows us to implement different getSpan methods that honor the span flags.
   *
   * @param <V> the Effect's configuration information.
   */
  abstract class SpanCollector<V> {
  
      private Class<? extends RTSpan<V>> mSpanClazz;
  
      protected SpanCollector(Class<? extends RTSpan<V>> spanClazz) {
          mSpanClazz = spanClazz;
      }
  
      /**
       * Equivalent to the Spanned.getSpans(int, int, Class<T>) method.
       * Return the markup objects (spans) attached to the specified slice of a Spannable.
       * The type of the spans is defined in the SpanCollector.
       *
       * @param str The Spannable to search for spans.
       * @param selection The selection within the Spannable to search for spans.
       * @param mode details see SpanCollectMode.
       *
       * @return the list of spans in this Spannable/Selection, never Null
       */
      protected abstract List<RTSpan<V>> getSpans(Spannable str, Selection selection, SpanCollectMode mode);
  
      /**
       * Return an array of the markup objects attached to the specified slice of a Spannable and whose
       * type is the specified type or a subclass of it (see Spanned.getSpans(int, int, Class<T>)).
       */
      final protected RTSpan<V>[] getSpansAndroid(Spannable str, int selStart, int selEnd) {
          RTSpan<V>[] spans = str.getSpans(selStart, selEnd, mSpanClazz);
          return spans == null ? (RTSpan<V>[]) Array.newInstance(mSpanClazz) : spans;
      }
  
      /**
       * @return True if the flags contain at least one of the values, False otherwise.
       */
      final protected boolean isOneFlagSet(int flags, int...value) {
          for (int flag : value) {
              if ((flags & flag) == flag) {
                  return true;
              }
          }
          return false;
      }
  
  }
  