/*
 * Copyright (C) 2016 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.google.android.exoplayer2.metadata;

import android.os.Parcel;
import android.os.Parcelable;
import android.support.annotation.Nullable;
import java.util.Arrays;
import java.util.List;

/**
 * A collection of metadata entries.
 */
public final class Metadata implements Parcelable {

  /**
   * A metadata entry.
   */
  public interface Entry extends Parcelable {}

  private final Entry[] entries;

  /**
   * @param entries The metadata entries.
   */
  public Metadata(Entry... entries) {
    this.entries = entries == null ? new Entry[0] : entries;
  }

  /**
   * @param entries The metadata entries.
   */
  public Metadata(List<? extends Entry> entries) {
    if (entries != null) {
      this.entries = new Entry[entries.size()];
      entries.toArray(this.entries);
    } else {
      this.entries = new Entry[0];
    }
  }

  /* package */ Metadata(Parcel in) {
    entries = new Metadata.Entry[in.readInt()];
    for (int i = 0; i < entries.length; i++) {
      entries[i] = in.readParcelable(Entry.class.getClassLoader());
    }
  }

  /**
   * Returns the number of metadata entries.
   */
  public int length() {
    return entries.length;
  }

  /**
   * Returns the entry at the specified index.
   *
   * @param index The index of the entry.
   * @return The entry at the specified index.
   */
  public Metadata.Entry get(int index) {
    return entries[index];
  }

  @Override
  public boolean equals(@Nullable Object obj) {
    if (this == obj) {
      return true;
    }
    if (obj == null || getClass() != obj.getClass()) {
      return false;
    }
    Metadata other = (Metadata) obj;
    return Arrays.equals(entries, other.entries);
  }

  @Override
  public int hashCode() {
    return Arrays.hashCode(entries);
  }

  // Parcelable implementation.

  @Override
  public int describeContents() {
    return 0;
  }

  @Override
  public void writeToParcel(Parcel dest, int flags) {
    dest.writeInt(entries.length);
    for (Entry entry : entries) {
      dest.writeParcelable(entry, 0);
    }
  }

  public static final Parcelable.Creator<Metadata> CREATOR = new Parcelable.Creator<Metadata>() {
    @Override
    public Metadata createFromParcel(Parcel in) {
      return new Metadata(in);
    }

    @Override
    public Metadata[] newArray(int size) {
      return new Metadata[0];
    }
  };

}
