Print Preview: Adding support for localized margin units and format.

chrome/browser/resources/print_preview/margin_utils.js

 // Copyright (c) 2011 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.
 
 cr.define('print_preview', function() {
   'use strict';
 
   /**
    * Checks if |text| has a valid margin value format. A valid format is
    * parsable as a number and is greater than zero.
    * Example: "1.00", "1", ".5", "1.1" are valid values.
    * Example: "1.4dsf", "-1" are invalid.
    * Note: The inch symbol (") at the end of |text| is allowed.
    *
    * @param {string} text The text to check.
    * @return {number} The margin value represented by |text| or null if |text|
    *     does not represent a valid number.
    */
   function extractMarginValue(text) {
-    // Remove whitespace anywhere in the string.
-    text.replace(/\s*/g, '');
+    // Removing whitespace anywhere in the string.
+    text = text.replace(/\s*/g, '');
     if (text.length == 0)
       return -1;
-    // Remove the inch(") symbol at end of string if present.
-    if (text.charAt(text.length - 1) == '\"')
-      text = text.slice(0, text.length - 1);
-    var regex = /^\d*(\.\d+)?$/
-    if (regex.test(text))
+    var validationRegex = getValidationRegExp();
+    if (validationRegex.test(text)) {
+      // Replacing decimal point with the dot symbol in order to use
+      // parseFloat() properly.
+      var replacementRegex = new RegExp('\\' +
+          print_preview.MarginSettings.decimalPoint + '{1}');
+      text = text.replace(replacementRegex, '.');
       return parseFloat(text);
+    }
     return -1;
   }
 
+  /**
+   * @return {RegExp} A regular expression for validating the input of the user.
+   *     It takes into account the user's locale.
+   */
+  function getValidationRegExp() {
+    var regex = new RegExp('(^\\d+)(\\' +
+       print_preview.MarginSettings.thousandsPoint +'\\d{3})*(\\'+
+       print_preview.MarginSettings.decimalPoint + '\\d+)*' +
+       (!print_preview.MarginSettings.useMetricSystem ? '"?' : '(mm)?') + '$');
+    return regex;
+  }
+
   var marginValidationStates = {
     TOO_SMALL: 0,
     WITHIN_RANGE: 1,
     TOO_BIG: 2,
     NOT_A_NUMBER: 3
   }
 
   /**
    * Checks  whether |value| is within range [0, limit].
    * @return {number} An appropriate value from enum |marginValidationStates|.
    */
   function validateMarginValue(value, limit) {
     if (value <= limit && value >= 0)
       return marginValidationStates.WITHIN_RANGE;
     else if (value < 0)
       return marginValidationStates.TOO_SMALL;
     else (value > limit)
       return marginValidationStates.TOO_BIG;
   }
 
   /**
-   * @param {sting} text The text to check (in inches).
+   * @param {sting} text The text to check in user's locale units.
    * @param {number} limit The upper bound of the valid margin range (in
    *     points).
    * @return {number} An appropriate value from enum |marginValidationStates|.
    */
   function validateMarginText(text, limit) {
     var value = extractMarginValue(text);
     if (value == -1)
       return marginValidationStates.NOT_A_NUMBER;
-    value = convertInchesToPoints(value);
+    value = print_preview.convertUserLocaleUnitsToPoints(value);
     return validateMarginValue(value, limit);
   }
 
-  /**
-   * @param {number} toConvert The value to convert in points
-   * @return {string} The equivalent text in inches.
-   */
-  function convertPointsToInchesText(toConvert) {
-    var inInches = convertPointsToInches(toConvert);
-    return convertInchesToInchesText(inInches);
+  function convertPointsToUserLocaleUnits(value) {
+    if (!print_preview.MarginSettings.useMetricSystem)
+      return convertPointsToInches(value);
+    else
+      return convertPointsToMillimeters(value);
+  }
+
+  function convertUserLocaleUnitsToPoints(value) {
+    if (!print_preview.MarginSettings.useMetricSystem)
+      return convertInchesToPoints(value);
+    else
+      return convertMillimetersToPoints(value);
   }
 
   /**
-   * @param {number} toConvert The value to convert in inches.
-   * @return {string} The equivalent text in inches with precision of two
-   *     digits.
+   * Converts |value| to user's locale units and then back to points. Note:
+   * Because of the precision the return value might be different than |value|.
+   * @param {number} value The value in points to convert.
+   * @return {number} The value in points after converting to user's locale
+   *     units  with a certain precision and back.
    */
-  function convertInchesToInchesText(toConvert) {
-    return toConvert.toFixed(2) + '"';
+  function convertPointsToUserLocaleUnitsAndBack(value) {
+    var inUserLocaleUnits =
+        convertPointsToUserLocaleUnits(value).toFixed(getDesiredPrecision());
+    return convertUserLocaleUnitsToPoints(inUserLocaleUnits);
   }
 
   /**
-   * Converts |value| to inches text (keeping 2 decimal digits) and then back to
-   * points. Note: Because of the precision the return value might be different
-   * than |value|.
-   * @param {number} value The value in points to convert.
-   * @return {number} The value in points after converting to inches with a
-   *     certain precision and back.
+   * @return {number} The number of decimal digits to keep based on the
+   *     measurement system used.
    */
-  function convertPointsToInchesTextAndBack(value) {
-    var text = convertPointsToInchesText(value);
-    var inches = extractMarginValue(text);
-    return convertInchesToPoints(inches);
+  function getDesiredPrecision() {
+    return print_preview.MarginSettings.useMetricSystem ? 0 : 2;
   }
 
   /**
+   * @param {number} toConvert The value to convert in points.
+   * @return {string} The equivalent text in user locale units with precision
+   *     of two digits.
+   */
+  function convertPointsToUserLocaleUnitsText(value) {
+    var inUserLocaleUnits =
+        convertPointsToUserLocaleUnits(value).toFixed(getDesiredPrecision());
+    var inUserLocaleUnitsText = inUserLocaleUnits.toString(10).replace(
+        /\./g, print_preview.MarginSettings.decimalPoint);
+    return !print_preview.MarginSettings.useMetricSystem ?
+        inUserLocaleUnitsText + '"' : inUserLocaleUnitsText + 'mm';
+  }
+
+  /**
    * Creates a Rect object. This object describes a rectangle in a 2D plane. The
    * units of |x|, |y|, |width|, |height| are chosen by clients of this class.
    * @constructor
    */
   function Rect(x, y, width, height) {
     // @type {number} Horizontal distance of the upper left corner from origin.
     this.x = x;
     // @type {number} Vertical distance of the upper left corner from origin.
     this.y = y;
     // @type {number} Width of |this| rectangle.
@@ skipping 20 matching lines @@
     /**
      * Clones |this| and returns the cloned object.
      * @return {Rect} A copy of |this|.
      */
     clone: function() {
       return new Rect(this.x, this.y, this.width, this.height);
     }
   };
 
   return {
-    convertInchesToInchesText: convertInchesToInchesText,
-    convertPointsToInchesTextAndBack:convertPointsToInchesTextAndBack,
-    convertPointsToInchesText: convertPointsToInchesText,
+    convertPointsToUserLocaleUnitsAndBack:
+        convertPointsToUserLocaleUnitsAndBack,
+    convertPointsToUserLocaleUnitsText: convertPointsToUserLocaleUnitsText,
+    convertUserLocaleUnitsToPoints: convertUserLocaleUnitsToPoints,
     extractMarginValue: extractMarginValue,
     marginValidationStates: marginValidationStates,
     Rect: Rect,
     validateMarginText: validateMarginText,
-    validateMarginValue: validateMarginValue
+    validateMarginValue: validateMarginValue,
+    getValidationRegExp: getValidationRegExp,
   };
 });