Upstream oodles of Chrome for Android code into Chromium.

chrome/android/java_staging/src/org/chromium/chrome/browser/omnibox/AnswerTextBuilder.java

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.omnibox;
+
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.text.Html;
+import android.text.Spannable;
+import android.text.SpannableStringBuilder;
+import android.text.TextPaint;
+import android.text.style.AbsoluteSizeSpan;
+import android.text.style.ForegroundColorSpan;
+import android.text.style.MetricAffectingSpan;
+import android.util.Log;
+
+import java.util.List;
+
+/**
+ * Helper class that builds Spannables to represent the styled text in answers from Answers in
+ * Suggest.
+ */
+class AnswerTextBuilder {
+    private static final String TAG = "AnswerTextBuilder";
+
+    // Types, sizes and colors specified at http://goto.google.com/ais_api.
+    private static final int ANSWERS_ANSWER_TEXT_TYPE = 1;
+    private static final int ANSWERS_HEADLINE_TEXT_TYPE = 2;
+    private static final int ANSWERS_TOP_ALIGNED_TEXT_TYPE = 3;
+    private static final int ANSWERS_DESCRIPTION_TEXT_TYPE = 4;
+    private static final int ANSWERS_DESCRIPTION_TEXT_NEGATIVE_TYPE = 5;
+    private static final int ANSWERS_DESCRIPTION_TEXT_POSITIVE_TYPE = 6;
+    private static final int ANSWERS_MORE_INFO_TEXT_TYPE = 7;
+    private static final int ANSWERS_SUGGESTION_TEXT_TYPE = 8;
+    private static final int ANSWERS_SUGGESTION_TEXT_POSITIVE_TYPE = 9;
+    private static final int ANSWERS_SUGGESTION_TEXT_NEGATIVE_TYPE = 10;
+    private static final int ANSWERS_SUGGESTION_LINK_COLOR_TYPE = 11;
+    private static final int ANSWERS_STATUS_TEXT_TYPE = 12;
+    private static final int ANSWERS_PERSONALIZED_SUGGESTION_TEXT_TYPE = 13;
+
+    private static final int ANSWERS_ANSWER_TEXT_SIZE_SP = 28;
+    private static final int ANSWERS_HEADLINE_TEXT_SIZE_SP = 24;
+    private static final int ANSWERS_TOP_ALIGNED_TEXT_SIZE_SP = 13;
+    private static final int ANSWERS_DESCRIPTION_TEXT_SIZE_SP = 15;
+    private static final int ANSWERS_DESCRIPTION_TEXT_NEGATIVE_SIZE_SP = 16;
+    private static final int ANSWERS_DESCRIPTION_TEXT_POSITIVE_SIZE_SP = 16;
+    private static final int ANSWERS_MORE_INFO_TEXT_SIZE_SP = 12;
+    private static final int ANSWERS_SUGGESTION_TEXT_SIZE_SP = 15;
+    private static final int ANSWERS_SUGGESTION_TEXT_POSITIVE_SIZE_SP = 15;
+    private static final int ANSWERS_SUGGESTION_TEXT_NEGATIVE_SIZE_SP = 15;
+    private static final int ANSWERS_SUGGESTION_LINK_COLOR_SIZE_SP = 15;
+    private static final int ANSWERS_STATUS_TEXT_SIZE_SP = 13;
+    private static final int ANSWERS_PERSONALIZED_SUGGESTION_TEXT_SIZE_SP = 15;
+
+    private static final int ANSWERS_ANSWER_TEXT_COLOR = Color.BLACK;
+    private static final int ANSWERS_HEADLINE_TEXT_COLOR = Color.BLACK;
+    private static final int ANSWERS_TOP_ALIGNED_TEXT_COLOR = Color.GRAY;
+    private static final int ANSWERS_DESCRIPTION_TEXT_COLOR = Color.BLACK;
+    private static final int ANSWERS_DESCRIPTION_TEXT_NEGATIVE_COLOR = 0xFFC53929;
+    private static final int ANSWERS_DESCRIPTION_TEXT_POSITIVE_COLOR = 0xFF0B8043;
+    private static final int ANSWERS_MORE_INFO_TEXT_COLOR = Color.BLACK;
+    private static final int ANSWERS_SUGGESTION_TEXT_COLOR = Color.BLACK;
+    private static final int ANSWERS_SUGGESTION_TEXT_POSITIVE_COLOR = Color.GREEN;
+    private static final int ANSWERS_SUGGESTION_TEXT_NEGATIVE_COLOR = Color.RED;
+    // TODO(jdonnelly): Links should be purple if visited.
+    private static final int ANSWERS_SUGGESTION_LINK_COLOR_COLOR = Color.BLUE;
+    private static final int ANSWERS_STATUS_TEXT_COLOR = Color.GRAY;
+    private static final int ANSWERS_PERSONALIZED_SUGGESTION_TEXT_COLOR = Color.BLACK;
+
+    /**
+     * Builds a Spannable containing all of the styled text in the supplied ImageLine.
+     *
+     * @param line All text fields within this line will be added to the returned Spannable.
+     *             types.
+     * @param metrics Font metrics which will be used to properly size and layout images and top-
+     *                aligned text.
+     * @param density Screen density which will be used to properly size and layout images and top-
+     *                aligned text.
+     */
+    static Spannable buildSpannable(
+            SuggestionAnswer.ImageLine line, Paint.FontMetrics metrics, float density) {
+        SpannableStringBuilder builder = new SpannableStringBuilder();
+
+        // Determine the height of the largest text element in the line.  This
+        // will be used to top-align text and scale images.
+        int maxTextHeightSp = getMaxTextHeightSp(line);
+
+        List<SuggestionAnswer.TextField> textFields = line.getTextFields();
+        for (int i = 0; i < textFields.size(); i++) {
+            appendAndStyleText(builder, textFields.get(i), maxTextHeightSp, metrics, density);
+        }
+        if (line.hasAdditionalText()) {
+            builder.append("  ");
+            SuggestionAnswer.TextField additionalText = line.getAdditionalText();
+            appendAndStyleText(builder, additionalText, maxTextHeightSp, metrics, density);
+        }
+        if (line.hasStatusText()) {
+            builder.append("  ");
+            SuggestionAnswer.TextField statusText = line.getStatusText();
+            appendAndStyleText(builder, statusText, maxTextHeightSp, metrics, density);
+        }
+
+        return builder;
+    }
+
+    /**
+     * Determine the height of the largest text field in the entire line.
+     *
+     * @param line An ImageLine containing the text fields.
+     * @return The height in SP.
+     */
+    static int getMaxTextHeightSp(SuggestionAnswer.ImageLine line) {
+        int maxHeightSp = 0;
+
+        List<SuggestionAnswer.TextField> textFields = line.getTextFields();
+        for (int i = 0; i < textFields.size(); i++) {
+            int height = getAnswerTextSizeSp(textFields.get(i).getType());
+            if (height > maxHeightSp) {
+                maxHeightSp = height;
+            }
+        }
+        if (line.hasAdditionalText()) {
+            int height = getAnswerTextSizeSp(line.getAdditionalText().getType());
+            if (height > maxHeightSp) {
+                maxHeightSp = height;
+            }
+        }
+        if (line.hasStatusText()) {
+            int height = getAnswerTextSizeSp(line.getStatusText().getType());
+            if (height > maxHeightSp) {
+                maxHeightSp = height;
+            }
+        }
+
+        return maxHeightSp;
+    }
+
+    /**
+     * Append the styled text in textField to the supplied builder.
+     *
+     * @param builder The builder to append the text to.
+     * @param textField The text field (with text and type) to append.
+     * @param maxTextHeightSp The height in SP of the largest text field in the entire line. Used to
+     *                        top-align text when specified.
+     * @param metrics Font metrics which will be used to properly size and layout images and top-
+     *                aligned text.
+     * @param density Screen density which will be used to properly size and layout images and top-
+     *                aligned text.
+    */
+    private static void appendAndStyleText(
+            SpannableStringBuilder builder, SuggestionAnswer.TextField textField,
+            int maxTextHeightSp, Paint.FontMetrics metrics, float density) {
+        String text = textField.getText();
+        int type = textField.getType();
+
+        // Unescape HTML entities (e.g. "&quot;", "&gt;").
+        text = Html.fromHtml(text).toString();
+
+        // Append as HTML (answer responses contain simple markup).
+        int start = builder.length();
+        builder.append(Html.fromHtml(text));
+        int end = builder.length();
+
+        // Apply styles according to the type.
+        AbsoluteSizeSpan sizeSpan = new AbsoluteSizeSpan(getAnswerTextSizeSp(type), true);
+        builder.setSpan(sizeSpan, start, end, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
+
+        ForegroundColorSpan colorSpan = new ForegroundColorSpan(getAnswerTextColor(type));
+        builder.setSpan(colorSpan, start, end, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
+
+        if (type == ANSWERS_TOP_ALIGNED_TEXT_TYPE) {
+            TopAlignedSpan topAlignedSpan =
+                    new TopAlignedSpan(
+                            ANSWERS_TOP_ALIGNED_TEXT_SIZE_SP, maxTextHeightSp, metrics, density);
+            builder.setSpan(topAlignedSpan, start, end, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
+        }
+    }
+
+    /**
+     * Return the SP text height for the specified answer text type.
+     *
+     * @param type The answer type as specified at http://goto.google.com/ais_api.
+     */
+    private static int getAnswerTextSizeSp(int type) {
+        switch (type) {
+            case ANSWERS_ANSWER_TEXT_TYPE:
+                return ANSWERS_ANSWER_TEXT_SIZE_SP;
+            case ANSWERS_HEADLINE_TEXT_TYPE:
+                return ANSWERS_HEADLINE_TEXT_SIZE_SP;
+            case ANSWERS_TOP_ALIGNED_TEXT_TYPE:
+                return ANSWERS_TOP_ALIGNED_TEXT_SIZE_SP;
+            case ANSWERS_DESCRIPTION_TEXT_TYPE:
+                return ANSWERS_DESCRIPTION_TEXT_SIZE_SP;
+            case ANSWERS_DESCRIPTION_TEXT_NEGATIVE_TYPE:
+                return ANSWERS_DESCRIPTION_TEXT_NEGATIVE_SIZE_SP;
+            case ANSWERS_DESCRIPTION_TEXT_POSITIVE_TYPE:
+                return ANSWERS_DESCRIPTION_TEXT_POSITIVE_SIZE_SP;
+            case ANSWERS_MORE_INFO_TEXT_TYPE:
+                return ANSWERS_MORE_INFO_TEXT_SIZE_SP;
+            case ANSWERS_SUGGESTION_TEXT_TYPE:
+                return ANSWERS_SUGGESTION_TEXT_SIZE_SP;
+            case ANSWERS_SUGGESTION_TEXT_POSITIVE_TYPE:
+                return ANSWERS_SUGGESTION_TEXT_POSITIVE_SIZE_SP;
+            case ANSWERS_SUGGESTION_TEXT_NEGATIVE_TYPE:
+                return ANSWERS_SUGGESTION_TEXT_NEGATIVE_SIZE_SP;
+            case ANSWERS_SUGGESTION_LINK_COLOR_TYPE:
+                return ANSWERS_SUGGESTION_LINK_COLOR_SIZE_SP;
+            case ANSWERS_STATUS_TEXT_TYPE:
+                return ANSWERS_STATUS_TEXT_SIZE_SP;
+            case ANSWERS_PERSONALIZED_SUGGESTION_TEXT_TYPE:
+                return ANSWERS_PERSONALIZED_SUGGESTION_TEXT_SIZE_SP;
+            default:
+                Log.w(TAG, "Unknown answer type: " + type);
+                return ANSWERS_SUGGESTION_TEXT_SIZE_SP;
+        }
+    }
+
+    /**
+     * Return the color code for the specified answer text type.
+     *
+     * @param type The answer type as specified at http://goto.google.com/ais_api.
+     */
+    private static int getAnswerTextColor(int type) {
+        switch (type) {
+            case ANSWERS_ANSWER_TEXT_TYPE:
+                return ANSWERS_ANSWER_TEXT_COLOR;
+            case ANSWERS_HEADLINE_TEXT_TYPE:
+                return ANSWERS_HEADLINE_TEXT_COLOR;
+            case ANSWERS_TOP_ALIGNED_TEXT_TYPE:
+                return ANSWERS_TOP_ALIGNED_TEXT_COLOR;
+            case ANSWERS_DESCRIPTION_TEXT_TYPE:
+                return ANSWERS_DESCRIPTION_TEXT_COLOR;
+            case ANSWERS_DESCRIPTION_TEXT_NEGATIVE_TYPE:
+                return ANSWERS_DESCRIPTION_TEXT_NEGATIVE_COLOR;
+            case ANSWERS_DESCRIPTION_TEXT_POSITIVE_TYPE:
+                return ANSWERS_DESCRIPTION_TEXT_POSITIVE_COLOR;
+            case ANSWERS_MORE_INFO_TEXT_TYPE:
+                return ANSWERS_MORE_INFO_TEXT_COLOR;
+            case ANSWERS_SUGGESTION_TEXT_TYPE:
+                return ANSWERS_SUGGESTION_TEXT_COLOR;
+            case ANSWERS_SUGGESTION_TEXT_POSITIVE_TYPE:
+                return ANSWERS_SUGGESTION_TEXT_POSITIVE_COLOR;
+            case ANSWERS_SUGGESTION_TEXT_NEGATIVE_TYPE:
+                return ANSWERS_SUGGESTION_TEXT_NEGATIVE_COLOR;
+            case ANSWERS_SUGGESTION_LINK_COLOR_TYPE:
+                return ANSWERS_SUGGESTION_LINK_COLOR_COLOR;
+            case ANSWERS_STATUS_TEXT_TYPE:
+                return ANSWERS_STATUS_TEXT_COLOR;
+            case ANSWERS_PERSONALIZED_SUGGESTION_TEXT_TYPE:
+                return ANSWERS_PERSONALIZED_SUGGESTION_TEXT_COLOR;
+            default:
+                Log.w(TAG, "Unknown answer type: " + type);
+                return ANSWERS_SUGGESTION_TEXT_COLOR;
+        }
+    }
+
+    /**
+     * Aligns the top of the spanned text with the top of some other specified text height. This is
+     * done by calculating the ascent of both text heights and shifting the baseline of the spanned
+     * text by the difference.  As a result, "top aligned" means the top of the ascents are
+     * aligned, which looks as expected in most cases (some glyphs in some fonts are drawn above
+     * the top of the ascent).
+     */
+    private static class TopAlignedSpan extends MetricAffectingSpan {
+        private int mBaselineShift;
+
+        /**
+         * Constructor for TopAlignedSpan.
+         *
+         * @param textHeightSp The total height in SP of the text covered by this span.
+         * @param maxTextHeightSp The total height in SP of the text we wish to top-align with.
+         * @param metrics The font metrics used to determine what proportion of the font height is
+         *                the ascent.
+         * @param density The display density.
+         */
+        public TopAlignedSpan(
+                int textHeightSp, int maxTextHeightSp, Paint.FontMetrics metrics, float density) {
+            float ascentProportion = metrics.ascent / (metrics.top - metrics.bottom);
+
+            int textAscentPx = (int) (textHeightSp * ascentProportion * density);
+            int maxTextAscentPx = (int) (maxTextHeightSp * ascentProportion * density);
+
+            this.mBaselineShift = -(maxTextAscentPx - textAscentPx);  // Up is -y.
+        }
+
+        @Override
+        public void updateDrawState(TextPaint tp) {
+            tp.baselineShift += mBaselineShift;
+        }
+
+        @Override
+        public void updateMeasureState(TextPaint tp) {
+            tp.baselineShift += mBaselineShift;
+        }
+    }
+}