package org.unicode.cldr.draft.keyboard;

import com.google.common.base.Function;
import com.google.common.base.MoreObjects;
import com.google.common.base.Objects;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;

/**
 * Object representing a 1 to 1 mapping between an ISO Position ({@link IsoLayoutPosition}) and the
 * provided output that is received when pressing that particular key. This object also includes any
 * keys that are available by "long-pressing" on the key (prominent on mobile phones).
 */
public final class CharacterMap implements Comparable<CharacterMap> {
  private final IsoLayoutPosition position;
  private final String output;
  private final ImmutableList<String> longPressKeys;
  private final boolean transformNo;

  private CharacterMap(IsoLayoutPosition position, String output,
      ImmutableList<String> longPressKeys, boolean transformNo) {
    this.position = Preconditions.checkNotNull(position);
    this.output = Preconditions.checkNotNull(output);
    this.longPressKeys = Preconditions.checkNotNull(longPressKeys);
    this.transformNo = transformNo;
  }

  /** Creates a new character map from the given position and output. */
  public static CharacterMap of(IsoLayoutPosition position, String output) {
    return new CharacterMap(position, output, ImmutableList.<String>of(), false);
  }

  /** Creates a new character map from the given position, output and long press keys. */
  public static CharacterMap of(IsoLayoutPosition position, String output,
      ImmutableList<String> longPressKeys) {
    return new CharacterMap(position, output, longPressKeys, false);
  }

  public IsoLayoutPosition position() {
    return position;
  }

  public String output() {
    return output;
  }

  public ImmutableList<String> longPressKeys() {
    return longPressKeys;
  }

  public CharacterMap markAsTransformNo() {
    return new CharacterMap(position, output, longPressKeys, true);
  }

  public boolean isTransformNo() {
    return transformNo;
  }

  @Override public String toString() {
    return MoreObjects.toStringHelper(this)
        .add("position", position)
        .add("output", output)
        .add("longPressKeys", longPressKeys)
        .toString();
  }

  @Override public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    if (o instanceof CharacterMap) {
      CharacterMap other = (CharacterMap) o;
      return position.equals(other.position) && output.equals(other.output)
          && longPressKeys.equals(other.longPressKeys);
    }
    return false;
  }

  @Override public int hashCode() {
    return Objects.hashCode(position, output, longPressKeys);
  }

  /** Sort character maps based on their ISO layout positions. */
  @Override public int compareTo(CharacterMap o) {
    return position.compareTo(o.position);
  }

  static Function<CharacterMap, IsoLayoutPosition> isoLayoutPositionFunction() {
    return CharacterMapToIsoLayoutFunction.INSTANCE;
  }

  private enum CharacterMapToIsoLayoutFunction
      implements Function<CharacterMap, IsoLayoutPosition> {
    INSTANCE;

    @Override
    public IsoLayoutPosition apply(CharacterMap character) {
      return character.position;
    }
  }
}