Fetch Suggestions by category

ios/chrome/browser/content_suggestions/content_suggestions_mediator.mm

 // Copyright 2017 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.
 
 #import "ios/chrome/browser/content_suggestions/content_suggestions_mediator.h"
 
 #include "base/mac/bind_objc_block.h"
 #include "base/memory/ptr_util.h"
 #include "base/optional.h"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 95 matching lines @@
 }
 
 @property(nonatomic, assign)
     ntp_snippets::ContentSuggestionsService* contentService;
 @property(nonatomic, strong, nonnull)
     NSMutableDictionary<ContentSuggestionsCategoryWrapper*,
                         ContentSuggestionsSectionInformation*>*
         sectionInformationByCategory;
 
 // Converts the data in |category| to ContentSuggestion and adds them to the
-// |contentArray|.
+// |contentArray| if the category is available.
 - (void)addContentInCategory:(ntp_snippets::Category&)category
                      toArray:(NSMutableArray<ContentSuggestion*>*)contentArray;
 
 // Adds the section information for |category| in
 // self.sectionInformationByCategory.
 - (void)addSectionInformationForCategory:(ntp_snippets::Category)category;
 
 // Returns a CategoryWrapper acting as a key for this section info.
 - (ContentSuggestionsCategoryWrapper*)categoryWrapperForSectionInfo:
     (ContentSuggestionsSectionInformation*)sectionInfo;
@@ skipping 30 matching lines @@
   self.contentService->DismissSuggestion(suggestion_id);
 }
 
 #pragma mark - ContentSuggestionsDataSource
 
 - (NSArray<ContentSuggestion*>*)allSuggestions {
   std::vector<ntp_snippets::Category> categories =
       self.contentService->GetCategories();
   NSMutableArray<ContentSuggestion*>* dataHolders = [NSMutableArray array];
   for (auto& category : categories) {
-    if (self.contentService->GetCategoryStatus(category) !=
-        ntp_snippets::CategoryStatus::AVAILABLE) {
-      continue;
-    }
-    if (!self.sectionInformationByCategory[
-            [ContentSuggestionsCategoryWrapper wrapperWithCategory:category]]) {
-      [self addSectionInformationForCategory:category];
-    }
     [self addContentInCategory:category toArray:dataHolders];
   }
   return dataHolders;
 }
 
+- (NSArray<ContentSuggestion*>*)suggestionsForSection:
+    (ContentSuggestionsSectionInformation*)sectionInfo {
+  ntp_snippets::Category category =
+      [[self categoryWrapperForSectionInfo:sectionInfo] category];
+
+  NSMutableArray* suggestions = [NSMutableArray array];
+  [self addContentInCategory:category toArray:suggestions];
+  return suggestions;
+}
+
 - (id<ContentSuggestionsImageFetcher>)imageFetcher {
   return self;
 }
 
 #pragma mark - ContentSuggestionsServiceObserver
 
 - (void)contentSuggestionsService:
             (ntp_snippets::ContentSuggestionsService*)suggestionsService
          newSuggestionsInCategory:(ntp_snippets::Category)category {
-  [self.dataSink dataAvailable];
+  ContentSuggestionsCategoryWrapper* wrapper =
+      [ContentSuggestionsCategoryWrapper wrapperWithCategory:category];
+  if (!self.sectionInformationByCategory[wrapper]) {
+    [self addSectionInformationForCategory:category];
+  }
+  [self.dataSink
+      dataAvailableForSection:self.sectionInformationByCategory[wrapper]];
 }
 
 - (void)contentSuggestionsService:
             (ntp_snippets::ContentSuggestionsService*)suggestionsService
                          category:(ntp_snippets::Category)category
                   statusChangedTo:(ntp_snippets::CategoryStatus)status {
   if (!ntp_snippets::IsCategoryStatusInitOrAvailable(status)) {
     // Remove the category from the UI if it is not available.
     ContentSuggestionsCategoryWrapper* wrapper =
         [[ContentSuggestionsCategoryWrapper alloc] initWithCategory:category];
@@ skipping 39 matching lines @@
       SuggestionIDForSectionID(
           [self categoryWrapperForSectionInfo:suggestionIdentifier.sectionInfo],
           suggestionIdentifier.IDInSection),
       base::BindBlockArc(callback));
 }
 
 #pragma mark - Private
 
 - (void)addContentInCategory:(ntp_snippets::Category&)category
                      toArray:(NSMutableArray<ContentSuggestion*>*)contentArray {
+  if (self.contentService->GetCategoryStatus(category) !=
+      ntp_snippets::CategoryStatus::AVAILABLE) {
+    return;
+  }
+  ContentSuggestionsCategoryWrapper* categoryWrapper =
+      [ContentSuggestionsCategoryWrapper wrapperWithCategory:category];
+  if (!self.sectionInformationByCategory[categoryWrapper]) {
+    [self addSectionInformationForCategory:category];
+  }
+
   const std::vector<ntp_snippets::ContentSuggestion>& suggestions =
       self.contentService->GetSuggestionsForCategory(category);
-  ContentSuggestionsCategoryWrapper* categoryWrapper =
-      [[ContentSuggestionsCategoryWrapper alloc] initWithCategory:category];
+
   for (auto& contentSuggestion : suggestions) {
     ContentSuggestion* suggestion = ConvertContentSuggestion(contentSuggestion);
+
     suggestion.type = TypeForCategory(category);
     suggestion.suggestionIdentifier.sectionInfo =
         self.sectionInformationByCategory[categoryWrapper];
 
     [contentArray addObject:suggestion];
   }
 }
 
 - (void)addSectionInformationForCategory:(ntp_snippets::Category)category {
   base::Optional<ntp_snippets::CategoryInfo> categoryInfo =
       self.contentService->GetCategoryInfo(category);
 
   ContentSuggestionsSectionInformation* sectionInfo =
       SectionInformationFromCategoryInfo(categoryInfo, category);
 
   self.sectionInformationByCategory[[ContentSuggestionsCategoryWrapper
       wrapperWithCategory:category]] = sectionInfo;
 }
 
 - (ContentSuggestionsCategoryWrapper*)categoryWrapperForSectionInfo:
     (ContentSuggestionsSectionInformation*)sectionInfo {
   return [[self.sectionInformationByCategory allKeysForObject:sectionInfo]
       firstObject];
 }
 
 @end