PrintPreview Cleanup: Rename and refactor getSelectedPagesValidity() function.

chrome/browser/resources/print_preview.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.
 
 var localStrings = new LocalStrings();
 
 // The total page count of the previewed document regardless of which pages the
 // user has selected.
 var totalPageCount = -1;
 
@@ skipping 492 matching lines @@
   if (previouslySelectedPages.length == 0)
     for (var i = 0; i < totalPageCount; i++)
       previouslySelectedPages.push(i+1);
 
   if (printSettings.deviceName != tempPrintSettings.deviceName) {
     updateControlsWithSelectedPrinterCapabilities();
     return;
   } else if (printSettings.isLandscape != tempPrintSettings.isLandscape) {
     setDefaultValuesAndRegeneratePreview();
     return;
-  } else if (getSelectedPagesValidityLevel() == 1) {
+  } else if (isSelectedPagesValid()) {
     var currentlySelectedPages = getSelectedPagesSet();
     if (!areArraysEqual(previouslySelectedPages, currentlySelectedPages)) {
       previouslySelectedPages = currentlySelectedPages;
       requestPrintPreview();
       return;
     }
   }
 
-  if (getSelectedPagesValidityLevel() != 1)
+  if (!isSelectedPagesValid())
     pageRangesFieldChanged();
 
   // Update the current tab title.
   document.title = localStrings.getStringF('printPreviewTitleFormat', jobTitle);
 
   createPDFPlugin(previewUid);
   updatePrintSummary();
   updatePrintButtonState();
   addEventListeners();
 }
@@ skipping 48 matching lines @@
 }
 
 /**
  * Updates the state of print button depending on the user selection.
  * The button is enabled only when the following conditions are true.
  * 1) The selected page ranges are valid.
  * 2) The number of copies is valid (if applicable).
  */
 function updatePrintButtonState() {
   if (getSelectedPrinterName() == PRINT_TO_PDF) {
-    $('print-button').disabled = (getSelectedPagesValidityLevel() != 1);
+    $('print-button').disabled = !isSelectedPagesValid();
   } else {
     $('print-button').disabled = (!isNumberOfCopiesValid() ||
-                                  getSelectedPagesValidityLevel() != 1);
+                                  !isSelectedPagesValid());
   }
 }
 
 window.addEventListener('DOMContentLoaded', onLoad);
 
 /**
  * Listener function that executes whenever a change occurs in the 'copies'
  * field.
  */
 function copiesFieldChanged() {
   updateCopiesButtonsState();
   $('collate-option').hidden = getCopies() <= 1;
 }
 
 /**
  * Executes whenever a blur event occurs on the 'individual-pages'
  * field or when the timer expires. It takes care of
  * 1) showing/hiding warnings/suggestions
  * 2) updating print button/summary
  */
 function pageRangesFieldChanged() {
   var currentlySelectedPages = getSelectedPagesSet();
   var individualPagesField = $('individual-pages');
   var individualPagesHint = $('individual-pages-hint');
-  var validityLevel = getSelectedPagesValidityLevel();
 
-  if (validityLevel == 1) {
+  if (isSelectedPagesValid()) {
     individualPagesField.classList.remove('invalid');
     fadeOutElement(individualPagesHint);
   } else {
     individualPagesField.classList.add('invalid');
     individualPagesHint.classList.remove('suggestion');
     individualPagesHint.innerHTML =
         localStrings.getStringF('pageRangeInstruction',
                                 localStrings.getString(
                                     'examplePageRangeText'));
     fadeInElement(individualPagesHint);
@@ skipping 31 matching lines @@
 function updatePrintSummary() {
   var printToPDF = getSelectedPrinterName() == PRINT_TO_PDF;
   var copies = printToPDF ? 1 : getCopies();
   var printSummary = $('print-summary');
 
   if (!printToPDF && !isNumberOfCopiesValid()) {
     printSummary.innerHTML = localStrings.getString('invalidNumberOfCopies');
     return;
   }
 
-  if (getSelectedPagesValidityLevel() != 1) {
+  if (!isSelectedPagesValid()) {
     printSummary.innerHTML = '';
     return;
   }
 
   var pageList = getSelectedPagesSet();
   var numOfSheets = pageList.length;
   var sheetsLabel = localStrings.getString('printPreviewSheetsLabelSingular');
   var numOfPagesText = '';
   var pagesLabel = '';
 
@@ skipping 97 matching lines @@
       if (singlePageNumber && singlePageNumber > 0 &&
           singlePageNumber <= totalPageCount) {
         pageList.push(parseInt(part, 10));
       }
     }
   }
   return pageList;
 }
 
 /**
- * Checks the 'individual-pages' field and returns -1 if nothing is valid, 0 if
- * it is partially valid, 1 if it is completely valid.
- * Note: This function is stricter than getSelectedPages(), in other words this
- * could return -1 and getSelectedPages() might still extract some pages.
+ * Validates the 'individual-pages' text field value.
+ *
+ * @return {boolean} true if the text is valid.
  */
-function getSelectedPagesValidityLevel() {
+function isSelectedPagesValid() {
   var pageText = $('individual-pages').value;
 
   if ($('all-pages').checked || pageText.length == 0)
-    return 1;
+    return true;
 
   var successfullyParsed = 0;

[dpapad, 2011/06/08 18:58:13]

We don't need this variable either anymore. Remove and simply return true at the
end of the function.

[dpapad, 2011/06/08 20:10:06]

Summarizing our online discussion, lets leave this as is for now to allow ranges
like 1,,,5 to be valid.

-  var failedToParse = 0;
-
   var parts = pageText.split(/,/);
 
   for (var i = 0; i < parts.length; ++i) {
     var part = parts[i].replace(/\s*/g, '');
     if (part.length == 0)
       continue;
 
     var match = part.match(/^([0-9]+)-([0-9]*)$/);
-    if (match && match[1]) {
+    if (match && isValidNonZeroPositiveInteger(match[1])) {
       var from = parseInt(match[1], 10);
       var to = match[2] ? parseInt(match[2], 10) : totalPageCount;
 
-      if (from && to && from <= to)
-        successfullyParsed += 1;
-      else
-        failedToParse += 1;
-
-    } else if (isInteger(part) && parseInt(part, 10) <= totalPageCount &&
-               parseInt(part, 10) > 0)
-      successfullyParsed += 1;
-    else
-      failedToParse += 1;
+      if (!to || from > to)
+        return false;
+    } else if (!isValidNonZeroPositiveInteger(part) ||
+               !(parseInt(part, 10) <= totalPageCount)) {
+      return false;
+    }
+    successfullyParsed += 1;
   }
-  if (successfullyParsed > 0 && failedToParse == 0)
-    return 1;
-  else if (successfullyParsed > 0 && failedToParse > 0)
-    return 0;
-  else
-    return -1;
-}
-
-function isSelectedPagesFieldValid() {
-  return (getSelectedPages().length != 0)
+  return successfullyParsed > 0
 }
 
 /**
+ * Returns true if |value| is a valid non zero positive integer.
+ * @param {string} value The string to be tested.
+ */
+function isValidNonZeroPositiveInteger(value) {
+  return isInteger(value) && parseInt(value, 10) > 0;
+}
+
+/**
  * Parses the selected page ranges, processes them and returns the results.
  * 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 getSelectedPageRanges() {
   var pageList = getSelectedPagesSet();
   var pageRanges = [];
   for (var i = 0; i < pageList.length; ++i) {
@@ skipping 54 matching lines @@
 
 /**
  * When the user stops typing in the page range textfield or clicks on the
  * 'all-pages' checkbox, a new print preview is requested, only if
  * 1) The input is compeletely valid (it can be parsed in its entirety).
  * 2) The newly selected pages differ from the previously selected.
  */
 function onPageSelectionMayHaveChanged() {
   if ($('print-pages').checked)
     pageRangesFieldChanged();
-  var validityLevel = getSelectedPagesValidityLevel();
   var currentlySelectedPages = getSelectedPagesSet();
 
   // Toggling between "all pages"/"some pages" radio buttons while having an
   // invalid entry in the page selection textfield still requires updating the
   // print summary and print button.
-  if (validityLevel < 1 ||
+  if (!isSelectedPagesValid() ||
       areArraysEqual(previouslySelectedPages, currentlySelectedPages)) {
     updatePrintButtonState();
     updatePrintSummary();
     return;
   }
 
   previouslySelectedPages = currentlySelectedPages;
   requestPrintPreview();
 }
 
@@ skipping 33 matching lines @@
   this.isLandscape = '';
 }
 
 /**
  * Takes a snapshot of the print settings.
  */
 PrintSettings.prototype.save = function() {
   this.deviceName = getSelectedPrinterName();
   this.isLandscape = isLandscape();
 }