/*
 * Copyright 2012 The Stanford MobiSocial Laboratory
 *
 * 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 mobisocial.musubi.util;

import android.graphics.Canvas;
import android.graphics.Paint;
import android.text.Layout;
import android.text.SpannableStringBuilder;
import android.text.style.LeadingMarginSpan.LeadingMarginSpan2;
import android.view.Display;
import android.view.View;
import android.widget.RelativeLayout;
import android.widget.TextView;

public class FlowTextHelper {

    private static boolean mNewClassAvailable;

    /* class initialization fails when this throws an exception */
    static {
        try {
            Class.forName("android.text.style.LeadingMarginSpan$LeadingMarginSpan2");
            mNewClassAvailable = true;
        } catch (Exception ex) {
            mNewClassAvailable = false;
        }
    }

    public static void tryFlowText(SpannableStringBuilder ss, View thumbnailView, TextView messageView,
            Display display) {
        // There is nothing I can do for older versions, so just return
        if (!mNewClassAvailable)
            return;

        // Get height and width of the image and height of the text line
        thumbnailView.measure(display.getWidth(), display.getHeight());
        int height = thumbnailView.getMeasuredHeight();
        int width = thumbnailView.getMeasuredWidth();
        float textLineHeight = messageView.getPaint().getTextSize();

        // Set the span according to the number of lines and width of the image
        int lines = (int) Math.round(height / textLineHeight);
        // For an html text you can use this line: SpannableStringBuilder ss =
        // (SpannableStringBuilder)Html.fromHtml(text);
        ss.setSpan(new MyLeadingMarginSpan2(lines, width), 0, ss.length(), 0);
        messageView.setText(ss);

        // Align the text with the image by removing the rule that the text is
        // to the right of the image
        RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) messageView
                .getLayoutParams();
        int[] rules = params.getRules();
        rules[RelativeLayout.RIGHT_OF] = 0;
    }

    static class MyLeadingMarginSpan2 implements LeadingMarginSpan2 {
        private int margin;

        private int lines;

        MyLeadingMarginSpan2(int lines, int margin) {
            this.margin = margin;
            this.lines = lines;
        }

        @Override
        public int getLeadingMargin(boolean first) {
            if (first) {
                return margin;
            } else {
                return 0;
            }
        }

        @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) {
        }

        @Override
        public int getLeadingMarginLineCount() {
            return lines;
        }
    };
}