Colorpicker validation handling (#10821)

* ColorTextField, helper methods, and regex for validating and handling text input

* Refactored structure to avoid creating new component for validation

* Style to adapt to error indicator

* Tests for validating input in ColorPickerPreview component's TextField

* Merge branch 'master' into colorpicker_validation

* Fix path to server class

* Fix test: Submit the new value

* Fix test: ignore Phantom JS

* Fix hsl+hsla validation patterns to accept '%', test value tweaking

* Merge branch 'master' of github.com:vaadin/framework into colorpicker_validation

* Fix: remove warning when color is updated from elsewhere

* Revisions: input validation only once, Logging level WARN

* Revisions: unit tests for color pattern matching

* Revisions: moved parsing to utility class, tests for parsing all accepted input formats

* Fixed import in tests, comments

* Revisions: Logger as constant, ignore utility class in serialization test

* Corner case tests

* Revisions: protected method for parsing error text, fix to test

* Revisions: NPE fix

2 files changed, 271 insertions, 58 deletions

diff --git a/server/src/main/java/com/vaadin/ui/components/colorpicker/ColorPickerPreview.java b/server/src/main/java/com/vaadin/ui/components/colorpicker/ColorPickerPreview.java
index f68ae0ce9f..57da8949bd 100644
--- a/server/src/main/java/com/vaadin/ui/components/colorpicker/ColorPickerPreview.java
+++ b/server/src/main/java/com/vaadin/ui/components/colorpicker/ColorPickerPreview.java
@@ -16,9 +16,15 @@
 package com.vaadin.ui.components.colorpicker;
 
 import java.util.Objects;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 import com.vaadin.data.HasValue;
+import com.vaadin.server.AbstractErrorMessage.ContentMode;
+import com.vaadin.server.ErrorMessage;
+import com.vaadin.server.UserError;
 import com.vaadin.shared.Registration;
+import com.vaadin.shared.ui.ErrorLevel;
 import com.vaadin.shared.ui.colorpicker.Color;
 import com.vaadin.ui.Component;
 import com.vaadin.ui.CssLayout;
@@ -31,6 +37,8 @@ import com.vaadin.ui.TextField;
  * @since 7.0.0
  */
 public class ColorPickerPreview extends CssLayout implements HasValue<Color> {
+    private static final Logger LOGGER = Logger
+            .getLogger(ColorPickerPreview.class.getName());
 
     private static final String STYLE_DARK_COLOR = "v-textfield-dark";
     private static final String STYLE_LIGHT_COLOR = "v-textfield-light";
@@ -86,6 +94,7 @@ public class ColorPickerPreview extends CssLayout implements HasValue<Color> {
 
         String colorCSS = color.getCSS();
         field.setValue(colorCSS);
+        field.setComponentError(null);
 
         oldValue = colorCSS;
 
@@ -120,68 +129,29 @@ public class ColorPickerPreview extends CssLayout implements HasValue<Color> {
     }
 
     private void valueChange(ValueChangeEvent<String> event) {
+        ErrorMessage errorMessage = null;
         String value = event.getValue();
+        value = Objects.toString(value, "").trim();
         Color oldColor = color;
         try {
-            if (value != null) {
-                /*
-                 * Description of supported formats see
-                 * http://www.w3schools.com/cssref/css_colors_legal.asp
-                 */
-                if (value.length() == 7 && value.startsWith("#")) {
-                    // CSS color format (e.g. #000000)
-                    int red = Integer.parseInt(value.substring(1, 3), 16);
-                    int green = Integer.parseInt(value.substring(3, 5), 16);
-                    int blue = Integer.parseInt(value.substring(5, 7), 16);
-                    color = new Color(red, green, blue);
-
-                } else if (value.startsWith("rgb")) {
-                    // RGB color format rgb/rgba(255,255,255,0.1)
-                    String[] colors = value.substring(value.indexOf('(') + 1,
-                            value.length() - 1).split(",");
-
-                    int red = Integer.parseInt(colors[0]);
-                    int green = Integer.parseInt(colors[1]);
-                    int blue = Integer.parseInt(colors[2]);
-                    if (colors.length > 3) {
-                        int alpha = (int) (Double.parseDouble(colors[3])
-                                * 255d);
-                        color = new Color(red, green, blue, alpha);
-                    } else {
-                        color = new Color(red, green, blue);
-                    }
-
-                } else if (value.startsWith("hsl")) {
-                    // HSL color format hsl/hsla(100,50%,50%,1.0)
-                    String[] colors = value.substring(value.indexOf('(') + 1,
-                            value.length() - 1).split(",");
-
-                    int hue = Integer.parseInt(colors[0]);
-                    int saturation = Integer
-                            .parseInt(colors[1].replace("%", ""));
-                    int lightness = Integer
-                            .parseInt(colors[2].replace("%", ""));
-                    int rgb = Color.HSLtoRGB(hue, saturation, lightness);
-
-                    if (colors.length > 3) {
-                        int alpha = (int) (Double.parseDouble(colors[3])
-                                * 255d);
-                        color = new Color(rgb);
-                        color.setAlpha(alpha);
-                    } else {
-                        color = new Color(rgb);
-                    }
-                }
-
-                oldValue = value;
-                fireEvent(new ValueChangeEvent<>(this, oldColor,
-                        event.isUserOriginated()));
-            }
 
-        } catch (NumberFormatException nfe) {
-            // Revert value
-            field.setValue(oldValue);
+            /*
+             * Description of supported formats see
+             * http://www.w3schools.com/cssref/css_colors_legal.asp
+             */
+            color = ColorUtil.stringToColor(value);
+
+            oldValue = value;
+            fireEvent(new ValueChangeEvent<>(this, oldColor,
+                    event.isUserOriginated()));
+        } catch (NumberFormatException e) {
+            // Pattern matching ensures the validity of
+            // the input, this should never happen
+            LOGGER.log(Level.INFO, e.getMessage());
+            errorMessage = new UserError(getUserErrorText(value),
+                    ContentMode.TEXT, ErrorLevel.WARNING);
         }
+        field.setComponentError(errorMessage);
     }
 
     @Override
@@ -224,4 +194,18 @@ public class ColorPickerPreview extends CssLayout implements HasValue<Color> {
             }
         }
     }
-}
+
+    /**
+     * Get the client error message text for color input parsing error.
+     *
+     * @param value
+     *            input which caused the error
+     * @return error message text
+     */
+    protected String getUserErrorText(String value) {
+        return value.isEmpty() ? "Input cannot be empty"
+                : "Input '".concat(value)
+                        .concat("' is not in any recognized format");
+    }
+
+}
\ No newline at end of file
diff --git a/server/src/main/java/com/vaadin/ui/components/colorpicker/ColorUtil.java b/server/src/main/java/com/vaadin/ui/components/colorpicker/ColorUtil.java
new file mode 100644
index 0000000000..ae942ea0ce
--- /dev/null
+++ b/server/src/main/java/com/vaadin/ui/components/colorpicker/ColorUtil.java
@@ -0,0 +1,229 @@
+/*
+ * Copyright 2000-2018 Vaadin Ltd.
+ *
+ * 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.vaadin.ui.components.colorpicker;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import com.vaadin.shared.ui.colorpicker.Color;
+
+/**
+ * Utility class for matching and parsing {@link Color} objects from
+ * {@code String} input.
+ *
+ * Description of supported formats see
+ * http://www.w3schools.com/cssref/css_colors_legal.asp
+ *
+ * @since
+ */
+public class ColorUtil {
+    private ColorUtil() {
+    }
+
+    /**
+     * Parses {@link Color} from any of the following {@link String} inputs:
+     * <br>
+     * - RGB hex (e.g. "#FFAA00"), {@link #HEX_PATTERN}<br>
+     * - RGB "function" (e.g. "rgb(128,0,255)"), {@link #RGB_PATTERN}<br>
+     * - RGBA "function" (e.g. "rgba(50,50,50,0.2)"), {@link #RGBA_PATTERN}<br>
+     * - HSL "function" (e.g. "hsl(50,50,50)"), {@link #HSL_PATTERN}<br>
+     * - HSLA "function" (e.g. "hsl(50,50,50,0.2)"), {@link #HSLA_PATTERN}
+     * <p>
+     * Parsing is case-insensitive.
+     *
+     * @param input
+     *            String input
+     * @return {@link Color} parsed from input
+     * @throws NumberFormatException
+     *             Input does not match any recognized pattern
+     */
+    public static Color stringToColor(String input) {
+        Matcher m = HEX_PATTERN.matcher(input);
+        if (m.matches()) {
+            return getHexPatternColor(m);
+        }
+        m = RGB_PATTERN.matcher(input);
+        if (m.matches()) {
+            return getRGBPatternColor(m);
+        }
+        m = RGBA_PATTERN.matcher(input);
+        if (m.matches()) {
+            return getRGBAPatternColor(m);
+        }
+        m = HSL_PATTERN.matcher(input);
+        if (m.matches()) {
+            return getHSLPatternColor(m);
+        }
+        m = HSLA_PATTERN.matcher(input);
+        if (m.matches()) {
+            return getHSLAPatternColor(m);
+        }
+
+        throw new NumberFormatException("Parsing color from input failed.");
+    }
+
+    /**
+     * Parses {@link Color} from matched hexadecimal {@link Matcher}.
+     *
+     * @param matcher
+     *            {@link Matcher} matching hexadecimal pattern with named regex
+     *            groups {@code red}, {@code green}, and {@code blue}
+     * @return {@link Color} parsed from {@link Matcher}
+     */
+    public static Color getHexPatternColor(Matcher matcher) {
+        int red = Integer.parseInt(matcher.group("red"), 16);
+        int green = Integer.parseInt(matcher.group("green"), 16);
+        int blue = Integer.parseInt(matcher.group("blue"), 16);
+        return new Color(red, green, blue);
+    }
+
+    /**
+     * Parses {@link Color} from matched RGB {@link Matcher}.
+     *
+     * @param matcher
+     *            {@link Matcher} matching RGB pattern with named regex groups
+     *            {@code red}, {@code green}, and {@code blue}
+     * @return {@link Color} parsed from {@link Matcher}
+     */
+    public static Color getRGBPatternColor(Matcher matcher) {
+        int red = Integer.parseInt(matcher.group("red"));
+        int green = Integer.parseInt(matcher.group("green"));
+        int blue = Integer.parseInt(matcher.group("blue"));
+        return new Color(red, green, blue);
+    }
+
+    /**
+     * Parses {@link Color} from matched RGBA {@link Matcher}.
+     *
+     * @param matcher
+     *            {@link Matcher} matching RGBA pattern with named regex groups
+     *            {@code red}, {@code green}, {@code blue}, and {@code alpha}
+     * @return {@link Color} parsed from {@link Matcher}
+     */
+    public static Color getRGBAPatternColor(Matcher matcher) {
+        Color c = getRGBPatternColor(matcher);
+        c.setAlpha((int) (Double.parseDouble(matcher.group("alpha")) * 255d));
+        return c;
+    }
+
+    /**
+     * Parses {@link Color} from matched HSL {@link Matcher}.
+     *
+     * @param matcher
+     *            {@link Matcher} matching HSL pattern with named regex groups
+     *            {@code hue}, {@code saturation}, and {@code light}
+     * @return {@link Color} parsed from {@link Matcher}
+     */
+    public static Color getHSLPatternColor(Matcher matcher) {
+        int hue = Integer.parseInt(matcher.group("hue"));
+        int saturation = Integer.parseInt(matcher.group("saturation"));
+        int light = Integer.parseInt(matcher.group("light"));
+        int rgb = Color.HSLtoRGB(hue, saturation, light);
+        return new Color(rgb);
+    }
+
+    /**
+     * Parses {@link Color} from matched HSLA {@link Matcher}.
+     *
+     * @param matcher
+     *            {@link Matcher} matching HSLA pattern with named regex groups
+     *            {@code hue}, {@code saturation}, {@code light}, and
+     *            {@code alpha}
+     * @return {@link Color} parsed from {@link Matcher}
+     */
+    public static Color getHSLAPatternColor(Matcher matcher) {
+        Color c = getHSLPatternColor(matcher);
+        c.setAlpha((int) (Double.parseDouble(matcher.group("alpha")) * 255d));
+        return c;
+    }
+
+    /**
+     * Case-insensitive {@link Pattern} with regular expression matching the
+     * default hexadecimal color presentation pattern:<br>
+     * '#' followed by six <code>[\da-fA-F]</code> characters.
+     * <p>
+     * Pattern contains named groups <code>red</code>, <code>green</code>, and
+     * <code>blue</code>, which represent the individual values.
+     */
+    public static final Pattern HEX_PATTERN = Pattern.compile(
+            "(?i)^#\\s*(?<red>[\\da-f]{2})(?<green>[\\da-f]{2})(?<blue>[\\da-f]{2}"
+                    + ")\\s*$");
+    /**
+     * Case-insensitive {@link Pattern} with regular expression matching common
+     * RGB color presentation patterns:<br>
+     * 'rgb' followed by three [0-255] number values. Values can be separated
+     * with either comma or whitespace.
+     * <p>
+     * Pattern contains named groups <code>red</code>, <code>green</code>, and
+     * <code>blue</code>, which represent the individual values.
+     */
+    public static final Pattern RGB_PATTERN = Pattern.compile(
+            "(?i)^rgb\\(\\s*(?<red>[01]?\\d{1,2}|2[0-4]\\d|25[0-5])(?:\\s*[,+|\\"
+                    + "s+]\\s*)(?<green>[01]?\\d\\d?|2[0-4]\\d|25[0-5])(?:\\s*[,"
+                    + "+|\\s+]\\s*)(?<blue>[01]?\\d\\d?|2[0-4]\\d|25[0-5])\\s*\\"
+                    + ")$");
+    /**
+     * Case-insensitive {@link Pattern} with regular expression matching common
+     * RGBA presentation patterns:<br>
+     * 'rgba' followed by three [0-255] values and one [0.0-1.0] value. Values
+     * can be separated with either comma or whitespace. The only accepted
+     * decimal marker is point ('.').
+     * <p>
+     * Pattern contains named groups <code>red</code>, <code>green</code>,
+     * <code>blue</code>, and <code>alpha</code>, which represent the individual
+     * values.
+     */
+    public static final Pattern RGBA_PATTERN = Pattern.compile(
+            "(?i)^rgba\\(\\s*(?<red>[01]?\\d{1,2}|2[0-4]\\d|25[0-5])(?:\\s*[,+|"
+                    + "\\s+]\\s*)(?<green>[01]?\\d\\d?|2[0-4]\\d|25[0-5])(?:\\s"
+                    + "*[,+|\\s+]\\s*)(?<blue>[01]?\\d\\d?|2[0-4]\\d|25[0-5])(?"
+                    + ":\\s*[,+|\\s+]\\s*)(?<alpha>0(?:\\.\\d{1,2})?|0?(?:\\.\\"
+                    + "d{1,2})|1(?:\\.0{1,2})?)\\s*\\)$");
+
+    /**
+     * Case-insensitive {@link Pattern} with regular expression matching common
+     * HSL presentation patterns:<br>
+     * 'hsl' followed by one [0-360] value and two [0-100] percentage value.
+     * Values can be separated with either comma or whitespace. The percent sign
+     * ('%') is optional.
+     * <p>
+     * Pattern contains named groups <code>hue</code>,<code>saturation</code>,
+     * and <code>light</code>, which represent the individual values.
+     */
+    public static final Pattern HSL_PATTERN = Pattern.compile(
+            "(?i)hsl\\(\\s*(?<hue>[12]?\\d{1,2}|3[0-5]\\d|360)(?:\\s*[,+|\\s+]"
+                    + "\\s*)(?<saturation>\\d{1,2}|100)(?:\\s*%?\\s*[,+|\\s+]\\"
+                    + "s*)(?<light>\\d{1,2}|100)(?:\\s*%?\\s*)\\)$");
+
+    /**
+     * Case-insensitive {@link Pattern} with regular expression matching common
+     * HSLA presentation patterns:<br>
+     * 'hsla' followed by one [0-360] value, two [0-100] percentage values, and
+     * one [0.0-1.0] value. Values can be separated with either comma or
+     * whitespace. The percent sign ('%') is optional. The only accepted decimal
+     * marker is point ('.').
+     * <p>
+     * Pattern contains named groups <code>hue</code>,<code>saturation</code>,
+     * <code>light</code>, and <code>alpha</code>, which represent the
+     * individual values.
+     */
+    public static final Pattern HSLA_PATTERN = Pattern.compile(
+            "(?i)hsla\\(\\s*(?<hue>[12]?\\d{1,2}|3[0-5]\\d|360)(?:\\s*[,+|\\s+"
+                    + "]\\s*)(?<saturation>\\d{1,2}|100)(?:\\s*%?\\s*[,+|\\s+]\\s*"
+                    + ")(?<light>\\d{1,2}|100)(?:\\s*%?[,+|\\s+]\\s*)(?<alpha>"
+                    + "0(?:\\.\\d{1,2})?|0?(?:\\.\\d{1,2})|1(?:\\.0{1,2})?)"
+                    + "\\s*\\)$");
+}