content: /*
   * Copyright (C) 2006 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 android.text.style;
  
  import android.annotation.NonNull;
  import android.annotation.Nullable;
  import android.graphics.LeakyTypefaceStorage;
  import android.graphics.Paint;
  import android.graphics.Typeface;
  import android.os.Parcel;
  import android.text.ParcelableSpan;
  import android.text.TextPaint;
  import android.text.TextUtils;
  
  /**
   * Span that updates the typeface of the text it's attached to. The <code>TypefaceSpan</code> can
   * be constructed either based on a font family or based on a <code>Typeface</code>. When
   * {@link #TypefaceSpan(String)} is used, the previous style of the <code>TextView</code> is kept.
   * When {@link #TypefaceSpan(Typeface)} is used, the <code>Typeface</code> style replaces the
   * <code>TextView</code>'s style.
   * <p>
   * For example, let's consider a <code>TextView</code> with
   * <code>android:textStyle="italic"</code> and a typeface created based on a font from resources,
   * with a bold style. When applying a <code>TypefaceSpan</code> based the typeface, the text will
   * only keep the bold style, overriding the <code>TextView</code>'s textStyle. When applying a
   * <code>TypefaceSpan</code> based on a font family: "monospace", the resulted text will keep the
   * italic style.
   * <pre>
   * Typeface myTypeface = Typeface.create(ResourcesCompat.getFont(context, R.font.acme),
   * Typeface.BOLD);
   * SpannableString string = new SpannableString("Text with typeface span.");
   * string.setSpan(new TypefaceSpan(myTypeface), 10, 18, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
   * string.setSpan(new TypefaceSpan("monospace"), 19, 22, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
   * </pre>
   * <img src="{@docRoot}reference/android/images/text/style/typefacespan.png" />
   * <figcaption>Text with <code>TypefaceSpan</code>s constructed based on a font from resource and
   * from a font family.</figcaption>
   */
  public class TypefaceSpan extends MetricAffectingSpan implements ParcelableSpan {
  
      @Nullable
      private final String mFamily;
  
      @Nullable
      private final Typeface mTypeface;
  
      /**
       * Constructs a {@link TypefaceSpan} based on the font family. The previous style of the
       * TextPaint is kept. If the font family is null, the text paint is not modified.
       *
       * @param family The font family for this typeface.  Examples include
       *               "monospace", "serif", and "sans-serif"
       */
      public TypefaceSpan(@Nullable String family) {
          this(family, null);
      }
  
      /**
       * Constructs a {@link TypefaceSpan} from a {@link Typeface}. The previous style of the
       * TextPaint is overridden and the style of the typeface is used.
       *
       * @param typeface the typeface
       */
      public TypefaceSpan(@NonNull Typeface typeface) {
          this(null, typeface);
      }
  
      /**
       * Constructs a {@link TypefaceSpan} from a  parcel.
       */
      public TypefaceSpan(@NonNull Parcel src) {
          mFamily = src.readString();
          mTypeface = LeakyTypefaceStorage.readTypefaceFromParcel(src);
      }
  
      private TypefaceSpan(@Nullable String family, @Nullable Typeface typeface) {
          mFamily = family;
          mTypeface = typeface;
      }
  
      @Override
      public int getSpanTypeId() {
          return getSpanTypeIdInternal();
      }
  
      /** @hide */
      @Override
      public int getSpanTypeIdInternal() {
          return TextUtils.TYPEFACE_SPAN;
      }
  
      @Override
      public int describeContents() {
          return 0;
      }
  
      @Override
      public void writeToParcel(@NonNull Parcel dest, int flags) {
          writeToParcelInternal(dest, flags);
      }
  
      /** @hide */
      @Override
      public void writeToParcelInternal(@NonNull Parcel dest, int flags) {
          dest.writeString(mFamily);
          LeakyTypefaceStorage.writeTypefaceToParcel(mTypeface, dest);
      }
  
      /**
       * Returns the font family name set in the span.
       *
       * @return the font family name
       * @see #TypefaceSpan(String)
       */
      @Nullable
      public String getFamily() {
          return mFamily;
      }
  
      /**
       * Returns the typeface set in the span.
       *
       * @return the typeface set
       * @see #TypefaceSpan(Typeface)
       */
      @Nullable
      public Typeface getTypeface() {
          return mTypeface;
      }
  
      @Override
      public void updateDrawState(@NonNull TextPaint ds) {
          updateTypeface(ds);
      }
  
      @Override
      public void updateMeasureState(@NonNull TextPaint paint) {
          updateTypeface(paint);
      }
  
      private void updateTypeface(@NonNull Paint paint) {
          if (mTypeface != null) {
              paint.setTypeface(mTypeface);
          } else if (mFamily != null) {
              applyFontFamily(paint, mFamily);
          }
      }
  
      private void applyFontFamily(@NonNull Paint paint, @NonNull String family) {
          int style;
          Typeface old = paint.getTypeface();
          if (old == null) {
              style = Typeface.NORMAL;
          } else {
              style = old.getStyle();
          }
          final Typeface styledTypeface = Typeface.create(family, style);
          int fake = style & ~styledTypeface.getStyle();
  
          if ((fake & Typeface.BOLD) != 0) {
              paint.setFakeBoldText(true);
          }
  
          if ((fake & Typeface.ITALIC) != 0) {
              paint.setTextSkewX(-0.25f);
          }
          paint.setTypeface(styledTypeface);
      }
  }
  