scanning: Sort page sizes in page size dropdown

Sort the page sizes and correctly select the default option.

Bug: 1059779
Change-Id: Ibfc1f482d84b75785ae790f3349b93839590327d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2532969
Commit-Queue: Jesse Schettler <jschettler@chromium.org>
Commit-Queue: Zentaro Kavanagh <zentaro@chromium.org>
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Auto-Submit: Jesse Schettler <jschettler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#827048}

chrome/test/data/webui/chromeos/scanning/page_size_select_test.js

@@ -9,7 +9,7 @@ import {getPageSizeString} from 'chrome://scanning/scanning_app_util.js';
 
 import {assertEquals, assertFalse, assertTrue} from '../../chai_assert.js';
 
-import {changeSelect} from './scanning_app_test_utils.js';
+import {assertOrderedAlphabetically, changeSelect} from './scanning_app_test_utils.js';
 
 const PageSize = {
   A4: chromeos.scanning.mojom.PageSize.kIsoA4,
@@ -86,4 +86,29 @@ export function pageSizeSelectTest() {
     assertEquals(2, select.length);
     assertFalse(select.disabled);
   });
+
+  test('pageSizesSortedCorrectly', () => {
+    pageSizeSelect.pageSizes = [PageSize.Letter, PageSize.Max, PageSize.A4];
+    flush();
+
+    // Verify the page sizes are sorted alphabetically except for the fit to
+    // scan area option, which should always be last. Verify that Letter is
+    // selected by default.
+    assertOrderedAlphabetically(
+        pageSizeSelect.pageSizes.slice(0, pageSizeSelect.pageSizes.length - 1),
+        (pageSize) => getPageSizeString(pageSize));
+    assertEquals(
+        PageSize.Max,
+        pageSizeSelect.pageSizes[pageSizeSelect.pageSizes.length - 1]);
+    assertEquals(PageSize.Letter.toString(), pageSizeSelect.selectedPageSize);
+  });
+
+  test('firstPageSizeUsedWhenDefaultNotAvailable', () => {
+    pageSizeSelect.pageSizes = [PageSize.Max, PageSize.A4];
+    flush();
+
+    // Verify the first page size in the sorted page sizes array is selected by
+    // default when Letter is not an available option.
+    assertEquals(PageSize.A4.toString(), pageSizeSelect.selectedPageSize);
+  });
 }

chrome/test/data/webui/chromeos/scanning/scanning_app_test.js

@@ -350,7 +350,7 @@ export function scanningAppTest() {
               firstCapabilities.colorModes[0].toString(),
               scanningApp.selectedColorMode);
           assertEquals(
-              firstCapabilities.sources[0].pageSizes[0].toString(),
+              firstCapabilities.sources[0].pageSizes[1].toString(),
               scanningApp.selectedPageSize);
           assertEquals(
               firstCapabilities.resolutions[0].toString(),

chromeos/components/scanning/resources/page_size_select.html

@@ -8,7 +8,8 @@
         disabled="[[disabled]]">
       <!-- TODO(jschettler): Sort the page sizes. -->
       <template is="dom-repeat" items="[[pageSizes]]" as="pageSize">
-        <option value="[[pageSize]]">
+        <option value="[[pageSize]]"
+            selected$="[[isDefaultPageSize_(pageSize)]]">
           [[getPageSizeString_(pageSize)]]
         </option>
       </template>

chromeos/components/scanning/resources/page_size_select.js

@@ -9,9 +9,12 @@ import './strings.m.js';
 import {I18nBehavior} from 'chrome://resources/js/i18n_behavior.m.js';
 import {html, Polymer} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
 
-import {getPageSizeString} from './scanning_app_util.js';
+import {alphabeticalCompare, getPageSizeString} from './scanning_app_util.js';
 import {SelectBehavior} from './select_behavior.js';
 
+/** @type {chromeos.scanning.mojom.PageSize} */
+const DEFAULT_PAGE_SIZE = chromeos.scanning.mojom.PageSize.kNaLetter;
+
 /**
  * @fileoverview
  * 'page-size-select' displays the available page sizes in a dropdown.
@@ -37,14 +40,68 @@ Polymer({
     },
   },
 
-  observers: ['onNumOptionsChange(pageSizes.length)'],
+  observers: [
+    'onNumOptionsChange(pageSizes.length)', 'onPageSizesChange_(pageSizes.*)'
+  ],
 
   /**
-   * @param {chromeos.scanning.mojom.PageSize} pageSize
+   * @param {!chromeos.scanning.mojom.PageSize} pageSize
    * @return {string}
    * @private
    */
   getPageSizeString_(pageSize) {
     return getPageSizeString(pageSize);
   },
+
+  /**
+   * Letter should be the default option if it exists. If not, use the first
+   * page size in the page sizes array.
+   * @return {string}
+   * @private
+   */
+  getDefaultSelectedPageSize_() {
+    let defaultPageSizeIndex = this.pageSizes.findIndex((pageSize) => {
+      return this.isDefaultPageSize_(pageSize);
+    });
+    if (defaultPageSizeIndex === -1) {
+      defaultPageSizeIndex = 0;
+    }
+
+    return this.pageSizes[defaultPageSizeIndex].toString();
+  },
+
+  /**
+   * Sorts the page sizes and sets the selected page size when the page sizes
+   * array changes.
+   * @private
+   */
+  onPageSizesChange_() {
+    if (this.pageSizes.length > 1) {
+      this.pageSizes = this.customSort(
+          this.pageSizes, alphabeticalCompare,
+          (pageSize) => getPageSizeString(pageSize));
+
+      // If the fit to scan area option exists, move it to the end of the page
+      // sizes array.
+      const fitToScanAreaIndex = this.pageSizes.findIndex((pageSize) => {
+        return pageSize === chromeos.scanning.mojom.PageSize.kMax;
+      });
+      if (fitToScanAreaIndex !== -1) {
+        this.pageSizes.push(this.pageSizes.splice(fitToScanAreaIndex, 1)[0]);
+      }
+    }
+
+    if (this.pageSizes.length > 0) {
+      this.selectedPageSize = this.getDefaultSelectedPageSize_();
+    }
+  },
+
+  /**
+   * @param {!chromeos.scanning.mojom.PageSize} pageSize
+   * @return {boolean}
+   * @private
+   */
+  isDefaultPageSize_(pageSize) {
+    return pageSize === DEFAULT_PAGE_SIZE;
+  },
 });

chromeos/components/scanning/resources/scanning_app.js

@@ -227,11 +227,6 @@ Polymer({
   onCapabilitiesReceived_(response) {
     this.capabilities_ = response.capabilities;
 
-    // Set the first options as the selected options since they will be the
-    // first options in the dropdowns.
-    this.selectedPageSize =
-        this.capabilities_.sources[0].pageSizes[0].toString();
-
     // TODO(jschettler): Change default file type back to PDF when it's
     // supported.
     this.selectedFileType = chromeos.scanning.mojom.FileType.kPng.toString();