/*
 * 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.IntRange;
import android.annotation.NonNull;
import android.annotation.Px;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.text.Layout;
import android.text.Spanned;

Paragraph affecting span, that draws a bitmap at the beginning of a text. The span also allows
setting a padding between the bitmap and the text. The default value of the padding is 0px. The
span should be attached from the first character of the text.

For example, an IconMarginSpan with a bitmap and a padding of 30px can be set
like this:
SpannableString string = new SpannableString("Text with icon and padding");
string.setSpan(new IconMarginSpan(bitmap, 30), 0, string.length(),
Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);




See Also:
for working with a Drawable instead of a Bitmap./**
 * Paragraph affecting span, that draws a bitmap at the beginning of a text. The span also allows
 * setting a padding between the bitmap and the text. The default value of the padding is 0px. The
 * span should be attached from the first character of the text.
 * <p>
 * For example, an <code>IconMarginSpan</code> with a bitmap and a padding of 30px can be set
 * like this:
 * <pre>
 * SpannableString string = new SpannableString("Text with icon and padding");
 * string.setSpan(new IconMarginSpan(bitmap, 30), 0, string.length(),
 * Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
 * </pre>
 * <img src="{@docRoot}reference/android/images/text/style/iconmarginspan.png" />
 * <figcaption>Text with <code>IconMarginSpan</code></figcaption>
 * <p>
 *
 * @see DrawableMarginSpan for working with a {@link android.graphics.drawable.Drawable} instead of
 * a {@link Bitmap}.
 */
public class IconMarginSpan implements LeadingMarginSpan, LineHeightSpan {

    @NonNull
    private final Bitmap mBitmap;
    @Px
    private final int mPad;

    
Creates an IconMarginSpan from a Bitmap. 
Params:
bitmap – bitmap to be rendered at the beginning of the text/**
     * Creates an {@link IconMarginSpan} from a {@link Bitmap}.
     *
     * @param bitmap bitmap to be rendered at the beginning of the text
     */
    public IconMarginSpan(@NonNull Bitmap bitmap) {
        this(bitmap, 0);
    }

    
Creates an IconMarginSpan from a Bitmap. 
Params:
bitmap – bitmap to be rendered at the beginning of the text
pad –    padding width, in pixels, between the bitmap and the text/**
     * Creates an {@link IconMarginSpan} from a {@link Bitmap}.
     *
     * @param bitmap bitmap to be rendered at the beginning of the text
     * @param pad    padding width, in pixels, between the bitmap and the text
     */
    public IconMarginSpan(@NonNull Bitmap bitmap, @IntRange(from = 0) int pad) {
        mBitmap = bitmap;
        mPad = pad;
    }

    @Override
    public int getLeadingMargin(boolean first) {
        return mBitmap.getWidth() + mPad;
    }

    @Override
    public void drawLeadingMargin(Canvas c, Paint p, int x, int dir,
            int top, int baseline, int bottom,
            CharSequence text, int start, int end,
            boolean first, Layout layout) {
        int st = ((Spanned) text).getSpanStart(this);
        int itop = layout.getLineTop(layout.getLineForOffset(st));

        if (dir < 0) {
            x -= mBitmap.getWidth();
        }

        c.drawBitmap(mBitmap, x, itop, p);
    }

    @Override
    public void chooseHeight(CharSequence text, int start, int end,
            int istartv, int v,
            Paint.FontMetricsInt fm) {
        if (end == ((Spanned) text).getSpanEnd(this)) {
            int ht = mBitmap.getHeight();

            int need = ht - (v + fm.descent - fm.ascent - istartv);
            if (need > 0) {
                fm.descent += need;
            }

            need = ht - (v + fm.bottom - fm.top - istartv);
            if (need > 0) {
                fm.bottom += need;
            }
        }
    }

}