/*
 * Copyright (C) 2014 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.amnesica.kryptey.inputmethod.keyboard.internal;

import android.content.Context;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.text.TextPaint;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.Gravity;
import android.widget.TextView;

import com.amnesica.kryptey.inputmethod.keyboard.Key;

import java.util.HashSet;

/**
 * The pop up key preview view.
 */
public class KeyPreviewView extends TextView {
  private final Rect mBackgroundPadding = new Rect();
  private static final HashSet<String> sNoScaleXTextSet = new HashSet<>();

  public KeyPreviewView(final Context context, final AttributeSet attrs) {
    this(context, attrs, 0);
  }

  public KeyPreviewView(final Context context, final AttributeSet attrs, final int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    setGravity(Gravity.CENTER);
  }

  public void setPreviewVisual(final Key key, final KeyboardIconsSet iconsSet,
                               final KeyDrawParams drawParams) {
    // What we show as preview should match what we show on a key top in onDraw().
    final int iconId = key.getIconId();
    if (iconId != KeyboardIconsSet.ICON_UNDEFINED) {
      setCompoundDrawables(null, null, null, key.getPreviewIcon(iconsSet));
      setText(null);
      return;
    }

    setCompoundDrawables(null, null, null, null);
    setTextColor(drawParams.mPreviewTextColor);
    setTextSize(TypedValue.COMPLEX_UNIT_PX, key.selectPreviewTextSize(drawParams));
    setTypeface(key.selectPreviewTypeface(drawParams));
    // TODO Should take care of temporaryShiftLabel here.
    setTextAndScaleX(key.getPreviewLabel());
  }

  private void setTextAndScaleX(final String text) {
    setTextScaleX(1.0f);
    setText(text);
    if (sNoScaleXTextSet.contains(text)) {
      return;
    }
    // TODO: Override {@link #setBackground(Drawable)} that is supported from API 16 and
    // calculate maximum text width.
    final Drawable background = getBackground();
    if (background == null) {
      return;
    }
    background.getPadding(mBackgroundPadding);
    final int maxWidth = background.getIntrinsicWidth() - mBackgroundPadding.left
        - mBackgroundPadding.right;
    final float width = getTextWidth(text, getPaint());
    if (width <= maxWidth) {
      sNoScaleXTextSet.add(text);
      return;
    }
    setTextScaleX(maxWidth / width);
  }

  public static void clearTextCache() {
    sNoScaleXTextSet.clear();
  }

  private static float getTextWidth(final String text, final TextPaint paint) {
    if (TextUtils.isEmpty(text)) {
      return 0.0f;
    }
    final int len = text.length();
    final float[] widths = new float[len];
    final int count = paint.getTextWidths(text, 0, len, widths);
    float width = 0;
    for (int i = 0; i < count; i++) {
      width += widths[i];
    }
    return width;
  }

    /*public void setPreviewBackground(boolean customColorEnabled, int customColor) {
        final Drawable background = getBackground();
        if (customColorEnabled)
            background.setColorFilter(customColor, PorterDuff.Mode.OVERLAY);
    }*/
}
