Print Preview: Refactoring/Cleaning up print_preview.js.

chrome/browser/resources/print_preview_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.
+
+/**
+ * Returns true if |toTest| contains only digits. Leading and trailing
+ * whitespace is allowed.
+ * @param {string} toTest The string to be tested.
+ */
+function isInteger(toTest) {
+  var numericExp = /^\s*[0-9]+\s*$/;
+  return numericExp.test(toTest);
+}
+
+/**
+ * Returns true if |value| is a valid non zero positive integer.
+ * @param {string} value The string to be tested.
+ *
+ * @return {boolean} true if the |value| is valid non zero positive integer.
+ */
+function isPositiveInteger(value) {
+  return isInteger(value) && parseInt(value, 10) > 0;
+}
+
+/**
+ * Returns true if the contents of the two arrays are equal.
+ * @param {Array} array1 The first array.
+ * @param {Array} array1 The second array.
+ *
+ * @return {boolean} true if the arrays are equal.
+ */
+function areArraysEqual(array1, array2) {
+  if (array1.length != array2.length)
+    return false;
+  for (var i = 0; i < array1.length; i++)
+    if(array1[i] != array2[i])
+      return false;
+  return true;
+}
+
+/**
+ * Removes duplicate elements from |inArray| and returns a new array.
+ * |inArray| is not affected. It assumes that |inArray| is already sorted.
+ *
+ * @param {Array} inArray The array to be processed.
+ */
+function removeDuplicates(inArray) {
+  var out = [];
+
+  if(inArray.length == 0)
+    return out;
+
+  out.push(inArray[0]);
+  for (var i = 1; i < inArray.length; ++i)
+    if(inArray[i] != inArray[i - 1])
+      out.push(inArray[i]);
+  return out;
+}
+
+/**
+ * Checks if |pageRangeText| represents a valid page selection.
+ * A valid selection has a parsable format and every page identifier is
+ * <= |totalPageCount| unless wildcards are used (see examples).
+ * Example: "1-4, 9, 3-6, 10, 11" is valid, assuming |totalPageCount| >= 11.
+ * Example: "1-4, 6-6" is valid, assuming |totalPageCount| >= 6.
+ * Example: "2-" is valid, assuming |totalPageCount| >= 2, means from 2 to the
+ * end.
+ * Example: "1-10000" is valid, regardless of |totalPageCount|, means from 1 to
+ * the end if |totalPageCount| < 10000.
+ * Example: "1-4dsf, 11" is invalid regardless of |totalPageCount|.
+ * Example: "4-2, 11, -6" is invalid regardless of |totalPageCount|.
+ *
+ * Note: If |totalPageCount| is undefined the validation does not take
+ * |totalPageCount| into account.
+ * Example: "34853253" is valid.
+ * Example: "1-4, 9, 3-6, 10, 11" is valid.
+ *
+ * @return {boolean} true if the |pageRangeText| is valid.
+ */
+function isPageRangeTextValid(pageRangeText, totalPageCount) {
+  var regex = /^\s*([0-9]+)\s*-\s*([0-9]*)\s*$/;
+  var successfullyParsed = 0;
+
+  // Splitting around commas.
+  var parts = pageRangeText.split(/,/);
+
+  for (var i = 0; i < parts.length; ++i) {
+    var match = parts[i].match(regex);
+    if (parts[i].length == 0)
+      continue;
+
+    if (match && match[1] && isPositiveInteger(match[1])) {
+      var from = parseInt(match[1], 10);
+      var to = isPositiveInteger(match[2]) ? parseInt(match[2], 10) :
+          totalPageCount;
+      if (from > to)
+        return false;
+    } else if (!isPositiveInteger(parts[i]) || (totalPageCount != -1 &&
+          parseInt(parts[i], 10) > totalPageCount)) {
+      return false;
+    }
+    successfullyParsed++;
+  }
+  return successfullyParsed > 0;
+}
+
+/**
+ * Returns a list of all pages specified in |pagesRangeText|. The pages are
+ * listed in the order they appear in |pageRangeText| and duplicates are not
+ * eliminated. If |pageRangeText| is not valid according to
+ * isPageRangeTextValid(), or |totalPageCount| is undefined an empty list is
+ * returned.
+ *
+ * @return {Array}
+ */
+function pageRangeTextToPageList(pageRangeText, totalPageCount) {
+  var pageList = [];
+  if ((totalPageCount && !isPageRangeTextValid(pageRangeText, totalPageCount))
+      || !totalPageCount) {
+    return pageList;
+  }
+
+  var regex = /^\s*([0-9]+)\s*-\s*([0-9]*)\s*$/;
+  var parts = pageRangeText.split(/,/);
+
+  for (var i = 0; i < parts.length; ++i) {
+    var match = parts[i].match(regex);
+
+    if (match && match[1]) {
+      var from = parseInt(match[1], 10);
+      var to = match[2] ? parseInt(match[2], 10) : totalPageCount;
+
+      for (var j = from; j <= Math.min(to, totalPageCount); ++j)
+        pageList.push(j);
+    } else {
+      var singlePageNumber = parseInt(parts[i], 10);
+      if (isPositiveInteger(singlePageNumber) &&
+          singlePageNumber <= totalPageCount) {
+        pageList.push(singlePageNumber);
+      }
+    }
+  }
+  return pageList;
+}
+
+/**
+ * Returns the contents of |pageList| in ascending order and without any
+ * duplicates. |pageList| is not affected.
+ *
+ * @return {Array}
+ */
+function pageListToPageSet(pageList) {
+  var pageSet = [];
+  if (pageList.length == 0)
+    return pageSet;
+  pageSet = pageList.slice(0);
+  pageSet.sort(function(a,b) { return a - b; });
+  pageSet = removeDuplicates(pageSet);
+  return pageSet;
+}
+
+/**
+ * Converts |pageSet| to page ranges. It squashes whenever possible.
+ * Example: '1-2,3,5-7' becomes 1-3,5-7.
+ *
+ * @return {Array} an array of page range objects. A page range object has
+ *     fields 'from' and 'to'.
+ */
+function pageSetToPageRanges(pageSet) {
+  var pageRanges = [];
+  for (var i = 0; i < pageSet.length; ++i) {
+    tempFrom = pageSet[i];
+    while (i + 1 < pageSet.length && pageSet[i + 1] == pageSet[i] + 1)
+      ++i;
+    tempTo = pageSet[i];
+    pageRanges.push({'from': tempFrom, 'to': tempTo});
+  }
+  return pageRanges;
+}