LatinIME/java/src/com/android/inputmethod/keyboard/Key.java

/*
 * Copyright (C) 2010 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.android.inputmethod.keyboard;

import static com.android.inputmethod.keyboard.Keyboard.CODE_OUTPUT_TEXT;
import static com.android.inputmethod.keyboard.Keyboard.CODE_SHIFT;
import static com.android.inputmethod.keyboard.Keyboard.CODE_SWITCH_ALPHA_SYMBOL;
import static com.android.inputmethod.keyboard.Keyboard.CODE_UNSPECIFIED;
import static com.android.inputmethod.keyboard.internal.KeyboardIconsSet.ICON_UNDEFINED;

import android.content.res.Resources;
import android.content.res.TypedArray;
import android.graphics.Rect;
import android.graphics.Typeface;
import android.graphics.drawable.Drawable;
import android.text.TextUtils;
import android.util.Log;
import android.util.Xml;

import com.android.inputmethod.keyboard.internal.KeySpecParser;
import com.android.inputmethod.keyboard.internal.KeySpecParser.MoreKeySpec;
import com.android.inputmethod.keyboard.internal.KeyStyles.KeyStyle;
import com.android.inputmethod.keyboard.internal.KeyboardIconsSet;
import com.android.inputmethod.latin.R;
import com.android.inputmethod.latin.StringUtils;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;

import java.util.Arrays;
import java.util.Locale;

/**
 * Class for describing the position and characteristics of a single key in the keyboard.
 */
public class Key {
    private static final String TAG = Key.class.getSimpleName();

    /**
     * The key code (unicode or custom code) that this key generates.
     */
    public final int mCode;
    public final int mAltCode;

    /** Label to display */
    public final String mLabel;
    /** Hint label to display on the key in conjunction with the label */
    public final String mHintLabel;
    /** Flags of the label */
    private final int mLabelFlags;
    private static final int LABEL_FLAGS_ALIGN_LEFT = 0x01;
    private static final int LABEL_FLAGS_ALIGN_RIGHT = 0x02;
    private static final int LABEL_FLAGS_ALIGN_LEFT_OF_CENTER = 0x08;
    private static final int LABEL_FLAGS_FONT_NORMAL = 0x10;
    private static final int LABEL_FLAGS_FONT_MONO_SPACE = 0x20;
    // Start of key text ratio enum values
    private static final int LABEL_FLAGS_FOLLOW_KEY_TEXT_RATIO_MASK = 0x1C0;
    private static final int LABEL_FLAGS_FOLLOW_KEY_LARGE_LETTER_RATIO = 0x40;
    private static final int LABEL_FLAGS_FOLLOW_KEY_LETTER_RATIO = 0x80;
    private static final int LABEL_FLAGS_FOLLOW_KEY_LABEL_RATIO = 0xC0;
    private static final int LABEL_FLAGS_FOLLOW_KEY_LARGE_LABEL_RATIO = 0x100;
    private static final int LABEL_FLAGS_FOLLOW_KEY_HINT_LABEL_RATIO = 0x140;
    // End of key text ratio mask enum values
    private static final int LABEL_FLAGS_HAS_POPUP_HINT = 0x200;
    private static final int LABEL_FLAGS_HAS_SHIFTED_LETTER_HINT = 0x400;
    private static final int LABEL_FLAGS_HAS_HINT_LABEL = 0x800;
    private static final int LABEL_FLAGS_WITH_ICON_LEFT = 0x1000;
    private static final int LABEL_FLAGS_WITH_ICON_RIGHT = 0x2000;
    private static final int LABEL_FLAGS_AUTO_X_SCALE = 0x4000;
    private static final int LABEL_FLAGS_PRESERVE_CASE = 0x8000;
    private static final int LABEL_FLAGS_SHIFTED_LETTER_ACTIVATED = 0x10000;
    private static final int LABEL_FLAGS_FROM_CUSTOM_ACTION_LABEL = 0x20000;
    private static final int LABEL_FLAGS_DISABLE_HINT_LABEL = 0x40000000;
    private static final int LABEL_FLAGS_DISABLE_ADDITIONAL_MORE_KEYS = 0x80000000;

    /** Icon to display instead of a label. Icon takes precedence over a label */
    private final int mIconId;
    /** Icon for disabled state */
    private final int mDisabledIconId;
    /** Preview version of the icon, for the preview popup */
    private final int mPreviewIconId;

    /** Width of the key, not including the gap */
    public final int mWidth;
    /** Height of the key, not including the gap */
    public final int mHeight;
    /** The horizontal gap around this key */
    public final int mHorizontalGap;
    /** The vertical gap below this key */
    public final int mVerticalGap;
    /** The visual insets */
    public final int mVisualInsetsLeft;
    public final int mVisualInsetsRight;
    /** X coordinate of the key in the keyboard layout */
    public final int mX;
    /** Y coordinate of the key in the keyboard layout */
    public final int mY;
    /** Hit bounding box of the key */
    public final Rect mHitBox = new Rect();

    /** Text to output when pressed. This can be multiple characters, like ".com" */
    public final CharSequence mOutputText;
    /** More keys */
    public final MoreKeySpec[] mMoreKeys;
    /** More keys column number and flags */
    private final int mMoreKeysColumnAndFlags;
    private static final int MORE_KEYS_COLUMN_MASK = 0x000000ff;
    private static final int MORE_KEYS_FLAGS_FIXED_COLUMN_ORDER = 0x80000000;
    private static final int MORE_KEYS_FLAGS_HAS_LABELS = 0x40000000;
    private static final int MORE_KEYS_FLAGS_NEEDS_DIVIDERS = 0x20000000;
    private static final int MORE_KEYS_FLAGS_EMBEDDED_MORE_KEY = 0x10000000;
    private static final String MORE_KEYS_AUTO_COLUMN_ORDER = "!autoColumnOrder!";
    private static final String MORE_KEYS_FIXED_COLUMN_ORDER = "!fixedColumnOrder!";
    private static final String MORE_KEYS_HAS_LABELS = "!hasLabels!";
    private static final String MORE_KEYS_NEEDS_DIVIDERS = "!needsDividers!";
    private static final String MORE_KEYS_EMBEDDED_MORE_KEY = "!embeddedMoreKey!";

    /** Background type that represents different key background visual than normal one. */
    public final int mBackgroundType;
    public static final int BACKGROUND_TYPE_NORMAL = 0;
    public static final int BACKGROUND_TYPE_FUNCTIONAL = 1;
    public static final int BACKGROUND_TYPE_ACTION = 2;
    public static final int BACKGROUND_TYPE_STICKY_OFF = 3;
    public static final int BACKGROUND_TYPE_STICKY_ON = 4;

    private final int mActionFlags;
    private static final int ACTION_FLAGS_IS_REPEATABLE = 0x01;
    private static final int ACTION_FLAGS_NO_KEY_PREVIEW = 0x02;
    private static final int ACTION_FLAGS_ALT_CODE_WHILE_TYPING = 0x04;
    private static final int ACTION_FLAGS_ENABLE_LONG_PRESS = 0x08;

    private final int mHashCode;

    /** The current pressed state of this key */
    private boolean mPressed;
    /** Key is enabled and responds on press */
    private boolean mEnabled = true;

    /**
     * This constructor is being used only for keys in more keys keyboard.
     */
    public Key(Keyboard.Params params, MoreKeySpec moreKeySpec, int x, int y, int width, int height,
            int labelFlags) {
        this(params, moreKeySpec.mLabel, null, moreKeySpec.mIconId, moreKeySpec.mCode,
                moreKeySpec.mOutputText, x, y, width, height, labelFlags);
    }

    /**
     * This constructor is being used only for key in popup suggestions pane.
     */
    public Key(Keyboard.Params params, String label, String hintLabel, int iconId,
            int code, String outputText, int x, int y, int width, int height, int labelFlags) {
        mHeight = height - params.mVerticalGap;
        mHorizontalGap = params.mHorizontalGap;
        mVerticalGap = params.mVerticalGap;
        mVisualInsetsLeft = mVisualInsetsRight = 0;
        mWidth = width - mHorizontalGap;
        mHintLabel = hintLabel;
        mLabelFlags = labelFlags;
        mBackgroundType = BACKGROUND_TYPE_NORMAL;
        mActionFlags = 0;
        mMoreKeys = null;
        mMoreKeysColumnAndFlags = 0;
        mLabel = label;
        mOutputText = outputText;
        mCode = code;
        mEnabled = (code != CODE_UNSPECIFIED);
        mAltCode = CODE_UNSPECIFIED;
        mIconId = iconId;
        mDisabledIconId = ICON_UNDEFINED;
        mPreviewIconId = ICON_UNDEFINED;
        // Horizontal gap is divided equally to both sides of the key.
        mX = x + mHorizontalGap / 2;
        mY = y;
        mHitBox.set(x, y, x + width + 1, y + height);

        mHashCode = computeHashCode(this);
    }

    /**
     * Create a key with the given top-left coordinate and extract its attributes from the XML
     * parser.
     * @param res resources associated with the caller's context
     * @param params the keyboard building parameters.
     * @param row the row that this key belongs to. row's x-coordinate will be the right edge of
     *        this key.
     * @param parser the XML parser containing the attributes for this key
     * @throws XmlPullParserException
     */
    public Key(Resources res, Keyboard.Params params, Keyboard.Builder.Row row,
            XmlPullParser parser) throws XmlPullParserException {
        final float horizontalGap = isSpacer() ? 0 : params.mHorizontalGap;
        final int keyHeight = row.mRowHeight;
        mVerticalGap = params.mVerticalGap;
        mHeight = keyHeight - mVerticalGap;

        final TypedArray keyAttr = res.obtainAttributes(Xml.asAttributeSet(parser),
                R.styleable.Keyboard_Key);

        final KeyStyle style = params.mKeyStyles.getKeyStyle(keyAttr, parser);
        final float keyXPos = row.getKeyX(keyAttr);
        final float keyWidth = row.getKeyWidth(keyAttr, keyXPos);
        final int keyYPos = row.getKeyY();

        // Horizontal gap is divided equally to both sides of the key.
        mX = Math.round(keyXPos + horizontalGap / 2);
        mY = keyYPos;
        mWidth = Math.round(keyWidth - horizontalGap);
        mHorizontalGap = Math.round(horizontalGap);
        mHitBox.set(Math.round(keyXPos), keyYPos, Math.round(keyXPos + keyWidth) + 1,
                keyYPos + keyHeight);
        // Update row to have current x coordinate.
        row.setXPos(keyXPos + keyWidth);

        mBackgroundType = style.getInt(keyAttr,
                R.styleable.Keyboard_Key_backgroundType, BACKGROUND_TYPE_NORMAL);

        mVisualInsetsLeft = Math.round(Keyboard.Builder.getDimensionOrFraction(keyAttr,
                R.styleable.Keyboard_Key_visualInsetsLeft, params.mBaseWidth, 0));
        mVisualInsetsRight = Math.round(Keyboard.Builder.getDimensionOrFraction(keyAttr,
                R.styleable.Keyboard_Key_visualInsetsRight, params.mBaseWidth, 0));
        mIconId = KeySpecParser.getIconId(style.getString(keyAttr,
                R.styleable.Keyboard_Key_keyIcon));
        mDisabledIconId = KeySpecParser.getIconId(style.getString(keyAttr,
                R.styleable.Keyboard_Key_keyIconDisabled));
        mPreviewIconId = KeySpecParser.getIconId(style.getString(keyAttr,
                R.styleable.Keyboard_Key_keyIconPreview));

        mLabelFlags = style.getFlag(keyAttr, R.styleable.Keyboard_Key_keyLabelFlags)
                | row.getDefaultKeyLabelFlags();
        final boolean needsToUpperCase = needsToUpperCase(mLabelFlags, params.mId.mElementId);
        final Locale locale = params.mId.mLocale;
        int actionFlags = style.getFlag(keyAttr, R.styleable.Keyboard_Key_keyActionFlags);
        String[] moreKeys = style.getStringArray(keyAttr, R.styleable.Keyboard_Key_moreKeys);

        int moreKeysColumn = style.getInt(keyAttr,
                R.styleable.Keyboard_Key_maxMoreKeysColumn, params.mMaxMoreKeysKeyboardColumn);
        int value;
        if ((value = KeySpecParser.getIntValue(moreKeys, MORE_KEYS_AUTO_COLUMN_ORDER, -1)) > 0) {
            moreKeysColumn = value & MORE_KEYS_COLUMN_MASK;
        }
        if ((value = KeySpecParser.getIntValue(moreKeys, MORE_KEYS_FIXED_COLUMN_ORDER, -1)) > 0) {
            moreKeysColumn = MORE_KEYS_FLAGS_FIXED_COLUMN_ORDER | (value & MORE_KEYS_COLUMN_MASK);
        }
        if (KeySpecParser.getBooleanValue(moreKeys, MORE_KEYS_HAS_LABELS)) {
            moreKeysColumn |= MORE_KEYS_FLAGS_HAS_LABELS;
        }
        if (KeySpecParser.getBooleanValue(moreKeys, MORE_KEYS_NEEDS_DIVIDERS)) {
            moreKeysColumn |= MORE_KEYS_FLAGS_NEEDS_DIVIDERS;
        }
        if (KeySpecParser.getBooleanValue(moreKeys, MORE_KEYS_EMBEDDED_MORE_KEY)) {
            moreKeysColumn |= MORE_KEYS_FLAGS_EMBEDDED_MORE_KEY;
        }
        mMoreKeysColumnAndFlags = moreKeysColumn;

        final String[] additionalMoreKeys;
        if ((mLabelFlags & LABEL_FLAGS_DISABLE_ADDITIONAL_MORE_KEYS) != 0) {
            additionalMoreKeys = null;
        } else {
            additionalMoreKeys = style.getStringArray(keyAttr,
                    R.styleable.Keyboard_Key_additionalMoreKeys);
        }
        moreKeys = KeySpecParser.insertAdditionalMoreKeys(moreKeys, additionalMoreKeys);
        if (moreKeys != null) {
            actionFlags |= ACTION_FLAGS_ENABLE_LONG_PRESS;
            mMoreKeys = new MoreKeySpec[moreKeys.length];
            for (int i = 0; i < moreKeys.length; i++) {
                mMoreKeys[i] = new MoreKeySpec(
                        moreKeys[i], needsToUpperCase, locale, params.mCodesSet);
            }
        } else {
            mMoreKeys = null;
        }
        mActionFlags = actionFlags;

        if ((mLabelFlags & LABEL_FLAGS_FROM_CUSTOM_ACTION_LABEL) != 0) {
            mLabel = params.mId.mCustomActionLabel;
        } else {
            mLabel = KeySpecParser.toUpperCaseOfStringForLocale(style.getString(keyAttr,
                    R.styleable.Keyboard_Key_keyLabel), needsToUpperCase, locale);
        }
        if ((mLabelFlags & LABEL_FLAGS_DISABLE_HINT_LABEL) != 0) {
            mHintLabel = null;
        } else {
            mHintLabel = KeySpecParser.toUpperCaseOfStringForLocale(style.getString(keyAttr,
                    R.styleable.Keyboard_Key_keyHintLabel), needsToUpperCase, locale);
        }
        String outputText = KeySpecParser.toUpperCaseOfStringForLocale(style.getString(keyAttr,
                R.styleable.Keyboard_Key_keyOutputText), needsToUpperCase, locale);
        final int code = KeySpecParser.parseCode(style.getString(keyAttr,
                R.styleable.Keyboard_Key_code), params.mCodesSet, CODE_UNSPECIFIED);
        // Choose the first letter of the label as primary code if not specified.
        if (code == CODE_UNSPECIFIED && TextUtils.isEmpty(outputText)
                && !TextUtils.isEmpty(mLabel)) {
            if (StringUtils.codePointCount(mLabel) == 1) {
                // Use the first letter of the hint label if shiftedLetterActivated flag is
                // specified.
                if (hasShiftedLetterHint() && isShiftedLetterActivated()
                        && !TextUtils.isEmpty(mHintLabel)) {
                    mCode = mHintLabel.codePointAt(0);
                } else {
                    mCode = mLabel.codePointAt(0);
                }
            } else {
                // In some locale and case, the character might be represented by multiple code
                // points, such as upper case Eszett of German alphabet.
                outputText = mLabel;
                mCode = CODE_OUTPUT_TEXT;
            }
        } else if (code == CODE_UNSPECIFIED && outputText != null) {
            if (StringUtils.codePointCount(outputText) == 1) {
                mCode = outputText.codePointAt(0);
                outputText = null;
            } else {
                mCode = CODE_OUTPUT_TEXT;
            }
        } else {
            mCode = KeySpecParser.toUpperCaseOfCodeForLocale(code, needsToUpperCase, locale);
        }
        mOutputText = outputText;
        mAltCode = KeySpecParser.toUpperCaseOfCodeForLocale(
                KeySpecParser.parseCode(style.getString(keyAttr,
                R.styleable.Keyboard_Key_altCode), params.mCodesSet, CODE_UNSPECIFIED),
                needsToUpperCase, locale);
        mHashCode = computeHashCode(this);

        keyAttr.recycle();

        if (hasShiftedLetterHint() && TextUtils.isEmpty(mHintLabel)) {
            Log.w(TAG, "hasShiftedLetterHint specified without keyHintLabel: " + this);
        }
    }

    private static boolean needsToUpperCase(int labelFlags, int keyboardElementId) {
        if ((labelFlags & LABEL_FLAGS_PRESERVE_CASE) != 0) return false;
        switch (keyboardElementId) {
        case KeyboardId.ELEMENT_ALPHABET_MANUAL_SHIFTED:
        case KeyboardId.ELEMENT_ALPHABET_AUTOMATIC_SHIFTED:
        case KeyboardId.ELEMENT_ALPHABET_SHIFT_LOCKED:
        case KeyboardId.ELEMENT_ALPHABET_SHIFT_LOCK_SHIFTED:
            return true;
        default:
            return false;
        }
    }

    private static int computeHashCode(Key key) {
        return Arrays.hashCode(new Object[] {
                key.mX,
                key.mY,
                key.mWidth,
                key.mHeight,
                key.mCode,
                key.mLabel,
                key.mHintLabel,
                key.mIconId,
                key.mBackgroundType,
                Arrays.hashCode(key.mMoreKeys),
                key.mOutputText,
                key.mActionFlags,
                key.mLabelFlags,
                // Key can be distinguishable without the following members.
                // key.mAltCode,
                // key.mDisabledIconId,
                // key.mPreviewIconId,
                // key.mHorizontalGap,
                // key.mVerticalGap,
                // key.mVisualInsetLeft,
                // key.mVisualInsetRight,
                // key.mMaxMoreKeysColumn,
        });
    }

    private boolean equals(Key o) {
        if (this == o) return true;
        return o.mX == mX
                && o.mY == mY
                && o.mWidth == mWidth
                && o.mHeight == mHeight
                && o.mCode == mCode
                && TextUtils.equals(o.mLabel, mLabel)
                && TextUtils.equals(o.mHintLabel, mHintLabel)
                && o.mIconId == mIconId
                && o.mBackgroundType == mBackgroundType
                && Arrays.equals(o.mMoreKeys, mMoreKeys)
                && TextUtils.equals(o.mOutputText, mOutputText)
                && o.mActionFlags == mActionFlags
                && o.mLabelFlags == mLabelFlags;
    }

    @Override
    public int hashCode() {
        return mHashCode;
    }

    @Override
    public boolean equals(Object o) {
        return o instanceof Key && equals((Key)o);
    }

    @Override
    public String toString() {
        return String.format("%s/%s %d,%d %dx%d %s/%s/%s",
                Keyboard.printableCode(mCode), mLabel, mX, mY, mWidth, mHeight, mHintLabel,
                KeyboardIconsSet.getIconName(mIconId), backgroundName(mBackgroundType));
    }

    private static String backgroundName(int backgroundType) {
        switch (backgroundType) {
        case BACKGROUND_TYPE_NORMAL: return "normal";
        case BACKGROUND_TYPE_FUNCTIONAL: return "functional";
        case BACKGROUND_TYPE_ACTION: return "action";
        case BACKGROUND_TYPE_STICKY_OFF: return "stickyOff";
        case BACKGROUND_TYPE_STICKY_ON: return "stickyOn";
        default: return null;
        }
    }

    public void markAsLeftEdge(Keyboard.Params params) {
        mHitBox.left = params.mHorizontalEdgesPadding;
    }

    public void markAsRightEdge(Keyboard.Params params) {
        mHitBox.right = params.mOccupiedWidth - params.mHorizontalEdgesPadding;
    }

    public void markAsTopEdge(Keyboard.Params params) {
        mHitBox.top = params.mTopPadding;
    }

    public void markAsBottomEdge(Keyboard.Params params) {
        mHitBox.bottom = params.mOccupiedHeight + params.mBottomPadding;
    }

    public final boolean isSpacer() {
        return this instanceof Spacer;
    }

    public boolean isShift() {
        return mCode == CODE_SHIFT;
    }

    public boolean isModifier() {
        return mCode == CODE_SHIFT || mCode == CODE_SWITCH_ALPHA_SYMBOL;
    }

    public boolean isRepeatable() {
        return (mActionFlags & ACTION_FLAGS_IS_REPEATABLE) != 0;
    }

    public boolean noKeyPreview() {
        return (mActionFlags & ACTION_FLAGS_NO_KEY_PREVIEW) != 0;
    }

    public boolean altCodeWhileTyping() {
        return (mActionFlags & ACTION_FLAGS_ALT_CODE_WHILE_TYPING) != 0;
    }

    public boolean isLongPressEnabled() {
        // We need not start long press timer on the key which has activated shifted letter.
        return (mActionFlags & ACTION_FLAGS_ENABLE_LONG_PRESS) != 0
                && (mLabelFlags & LABEL_FLAGS_SHIFTED_LETTER_ACTIVATED) == 0;
    }

    public Typeface selectTypeface(Typeface defaultTypeface) {
        // TODO: Handle "bold" here too?
        if ((mLabelFlags & LABEL_FLAGS_FONT_NORMAL) != 0) {
            return Typeface.DEFAULT;
        } else if ((mLabelFlags & LABEL_FLAGS_FONT_MONO_SPACE) != 0) {
            return Typeface.MONOSPACE;
        } else {
            return defaultTypeface;
        }
    }

    public int selectTextSize(int letterSize, int largeLetterSize, int labelSize,
            int largeLabelSize, int hintLabelSize) {
        switch (mLabelFlags & LABEL_FLAGS_FOLLOW_KEY_TEXT_RATIO_MASK) {
        case LABEL_FLAGS_FOLLOW_KEY_LETTER_RATIO:
            return letterSize;
        case LABEL_FLAGS_FOLLOW_KEY_LARGE_LETTER_RATIO:
            return largeLetterSize;
        case LABEL_FLAGS_FOLLOW_KEY_LABEL_RATIO:
            return labelSize;
        case LABEL_FLAGS_FOLLOW_KEY_LARGE_LABEL_RATIO:
            return largeLabelSize;
        case LABEL_FLAGS_FOLLOW_KEY_HINT_LABEL_RATIO:
            return hintLabelSize;
        default: // No follow key ratio flag specified.
            return StringUtils.codePointCount(mLabel) == 1 ? letterSize : labelSize;
        }
    }

    public boolean isAlignLeft() {
        return (mLabelFlags & LABEL_FLAGS_ALIGN_LEFT) != 0;
    }

    public boolean isAlignRight() {
        return (mLabelFlags & LABEL_FLAGS_ALIGN_RIGHT) != 0;
    }

    public boolean isAlignLeftOfCenter() {
        return (mLabelFlags & LABEL_FLAGS_ALIGN_LEFT_OF_CENTER) != 0;
    }

    public boolean hasPopupHint() {
        return (mLabelFlags & LABEL_FLAGS_HAS_POPUP_HINT) != 0;
    }

    public boolean hasShiftedLetterHint() {
        return (mLabelFlags & LABEL_FLAGS_HAS_SHIFTED_LETTER_HINT) != 0;
    }

    public boolean hasHintLabel() {
        return (mLabelFlags & LABEL_FLAGS_HAS_HINT_LABEL) != 0;
    }

    public boolean hasLabelWithIconLeft() {
        return (mLabelFlags & LABEL_FLAGS_WITH_ICON_LEFT) != 0;
    }

    public boolean hasLabelWithIconRight() {
        return (mLabelFlags & LABEL_FLAGS_WITH_ICON_RIGHT) != 0;
    }

    public boolean needsXScale() {
        return (mLabelFlags & LABEL_FLAGS_AUTO_X_SCALE) != 0;
    }

    public boolean isShiftedLetterActivated() {
        return (mLabelFlags & LABEL_FLAGS_SHIFTED_LETTER_ACTIVATED) != 0;
    }

    public int getMoreKeysColumn() {
        return mMoreKeysColumnAndFlags & MORE_KEYS_COLUMN_MASK;
    }

    public boolean isFixedColumnOrderMoreKeys() {
        return (mMoreKeysColumnAndFlags & MORE_KEYS_FLAGS_FIXED_COLUMN_ORDER) != 0;
    }

    public boolean hasLabelsInMoreKeys() {
        return (mMoreKeysColumnAndFlags & MORE_KEYS_FLAGS_HAS_LABELS) != 0;
    }

    public int getMoreKeyLabelFlags() {
        return hasLabelsInMoreKeys()
                ? LABEL_FLAGS_FOLLOW_KEY_LABEL_RATIO
                : LABEL_FLAGS_FOLLOW_KEY_LETTER_RATIO;
    }

    public boolean needsDividersInMoreKeys() {
        return (mMoreKeysColumnAndFlags & MORE_KEYS_FLAGS_NEEDS_DIVIDERS) != 0;
    }

    public boolean hasEmbeddedMoreKey() {
        return (mMoreKeysColumnAndFlags & MORE_KEYS_FLAGS_EMBEDDED_MORE_KEY) != 0;
    }

    public Drawable getIcon(KeyboardIconsSet iconSet, int alpha) {
        final int iconId = mEnabled ? mIconId : mDisabledIconId;
        final Drawable icon = iconSet.getIconDrawable(iconId);
        if (icon != null) {
            icon.setAlpha(alpha);
        }
        return icon;
    }

    public Drawable getPreviewIcon(KeyboardIconsSet iconSet) {
        return mPreviewIconId != ICON_UNDEFINED
                ? iconSet.getIconDrawable(mPreviewIconId)
                : iconSet.getIconDrawable(mIconId);
    }

    /**
     * Informs the key that it has been pressed, in case it needs to change its appearance or
     * state.
     * @see #onReleased()
     */
    public void onPressed() {
        mPressed = true;
    }

    /**
     * Informs the key that it has been released, in case it needs to change its appearance or
     * state.
     * @see #onPressed()
     */
    public void onReleased() {
        mPressed = false;
    }

    public boolean isEnabled() {
        return mEnabled;
    }

    public void setEnabled(boolean enabled) {
        mEnabled = enabled;
    }

    /**
     * Detects if a point falls on this key.
     * @param x the x-coordinate of the point
     * @param y the y-coordinate of the point
     * @return whether or not the point falls on the key. If the key is attached to an edge, it
     * will assume that all points between the key and the edge are considered to be on the key.
     * @see #markAsLeftEdge(Keyboard.Params) etc.
     */
    public boolean isOnKey(int x, int y) {
        return mHitBox.contains(x, y);
    }

    /**
     * Returns the square of the distance to the nearest edge of the key and the given point.
     * @param x the x-coordinate of the point
     * @param y the y-coordinate of the point
     * @return the square of the distance of the point from the nearest edge of the key
     */
    public int squaredDistanceToEdge(int x, int y) {
        final int left = mX;
        final int right = left + mWidth;
        final int top = mY;
        final int bottom = top + mHeight;
        final int edgeX = x < left ? left : (x > right ? right : x);
        final int edgeY = y < top ? top : (y > bottom ? bottom : y);
        final int dx = x - edgeX;
        final int dy = y - edgeY;
        return dx * dx + dy * dy;
    }

    private final static int[] KEY_STATE_NORMAL_HIGHLIGHT_ON = {
        android.R.attr.state_checkable,
        android.R.attr.state_checked
    };

    private final static int[] KEY_STATE_PRESSED_HIGHLIGHT_ON = {
        android.R.attr.state_pressed,
        android.R.attr.state_checkable,
        android.R.attr.state_checked
    };

    private final static int[] KEY_STATE_NORMAL_HIGHLIGHT_OFF = {
        android.R.attr.state_checkable
    };

    private final static int[] KEY_STATE_PRESSED_HIGHLIGHT_OFF = {
        android.R.attr.state_pressed,
        android.R.attr.state_checkable
    };

    private final static int[] KEY_STATE_NORMAL = {
    };

    private final static int[] KEY_STATE_PRESSED = {
        android.R.attr.state_pressed
    };

    // functional normal state (with properties)
    private static final int[] KEY_STATE_FUNCTIONAL_NORMAL = {
            android.R.attr.state_single
    };

    // functional pressed state (with properties)
    private static final int[] KEY_STATE_FUNCTIONAL_PRESSED = {
            android.R.attr.state_single,
            android.R.attr.state_pressed
    };

    // action normal state (with properties)
    private static final int[] KEY_STATE_ACTIVE_NORMAL = {
            android.R.attr.state_active
    };

    // action pressed state (with properties)
    private static final int[] KEY_STATE_ACTIVE_PRESSED = {
            android.R.attr.state_active,
            android.R.attr.state_pressed
    };

    /**
     * Returns the drawable state for the key, based on the current state and type of the key.
     * @return the drawable state of the key.
     * @see android.graphics.drawable.StateListDrawable#setState(int[])
     */
    public int[] getCurrentDrawableState() {
        switch (mBackgroundType) {
        case BACKGROUND_TYPE_FUNCTIONAL:
            return mPressed ? KEY_STATE_FUNCTIONAL_PRESSED : KEY_STATE_FUNCTIONAL_NORMAL;
        case BACKGROUND_TYPE_ACTION:
            return mPressed ? KEY_STATE_ACTIVE_PRESSED : KEY_STATE_ACTIVE_NORMAL;
        case BACKGROUND_TYPE_STICKY_OFF:
            return mPressed ? KEY_STATE_PRESSED_HIGHLIGHT_OFF : KEY_STATE_NORMAL_HIGHLIGHT_OFF;
        case BACKGROUND_TYPE_STICKY_ON:
            return mPressed ? KEY_STATE_PRESSED_HIGHLIGHT_ON : KEY_STATE_NORMAL_HIGHLIGHT_ON;
        default: /* BACKGROUND_TYPE_NORMAL */
            return mPressed ? KEY_STATE_PRESSED : KEY_STATE_NORMAL;
        }
    }

    public static class Spacer extends Key {
        public Spacer(Resources res, Keyboard.Params params, Keyboard.Builder.Row row,
                XmlPullParser parser) throws XmlPullParserException {
            super(res, params, row, parser);
        }

        /**
         * This constructor is being used only for divider in more keys keyboard.
         */
        protected Spacer(Keyboard.Params params, int x, int y, int width, int height) {
            super(params, null, null, ICON_UNDEFINED, CODE_UNSPECIFIED,
                    null, x, y, width, height, 0);
        }
    }
}