Fetch images for ContentSuggestions

ios/chrome/browser/content_suggestions/content_suggestions_mediator.mm

Index: ios/chrome/browser/content_suggestions/content_suggestions_mediator.mm
diff --git a/ios/chrome/browser/content_suggestions/content_suggestions_mediator.mm b/ios/chrome/browser/content_suggestions/content_suggestions_mediator.mm
index 791619f6ef82103cbacc5cda9c4329ee71766b27..c2f67f7a863e6887ad9aeb4bb3d4f7b3b0f8f84b 100644
--- a/ios/chrome/browser/content_suggestions/content_suggestions_mediator.mm
+++ b/ios/chrome/browser/content_suggestions/content_suggestions_mediator.mm
@@ -15,6 +15,7 @@
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestion.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestion_id.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_data_sink.h"
+#import "ios/chrome/browser/ui/content_suggestions/content_suggestions_image_fetcher.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_item.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_section_information.h"
 #include "ui/gfx/image/image.h"
@@ -83,9 +84,18 @@ ContentSuggestionsSectionInformation* SectionInformationFromCategoryInfo(
   return sectionInfo;
 }
 
+// Returns a ntp_snippets::ID based on a Objective-C Category and the ID in the
+// category.
+ntp_snippets::ContentSuggestion::ID SuggestionIDForSectionID(

[marq (ping after 24h), 2017/02/21 11:27:08]

Should this be a method on ContentSuggestionsCategoryWrapper?

[gambard, 2017/02/21 15:07:53]

Maybe. As they are only used in this file, I am not sure at the moment, and this
is why there are implemented as C function. If I need to move them around it
would be very easy.

+    ContentSuggestionsCategoryWrapper* category,
+    const std::string& id_in_category) {
+  return ntp_snippets::ContentSuggestion::ID(category.category, id_in_category);
+}
+
 }  // namespace
 
-@interface ContentSuggestionsMediator ()<ContentSuggestionsServiceObserver> {
+@interface ContentSuggestionsMediator ()<ContentSuggestionsImageFetcher,
+                                         ContentSuggestionsServiceObserver> {
   // Bridge for this class to become an observer of a ContentSuggestionsService.
   std::unique_ptr<ContentSuggestionsServiceBridge> _suggestionBridge;
 }
@@ -106,6 +116,10 @@ ContentSuggestionsSectionInformation* SectionInformationFromCategoryInfo(
 // self.sectionInformationByCategory.
 - (void)addSectionInformationForCategory:(ntp_snippets::Category)category;
 
+// Returns a CategoryWrapper acting as a key for this section info.
+- (ContentSuggestionsCategoryWrapper*)categoryWrapperForSectionInfo:
+    (ContentSuggestionsSectionInformation*)sectionInfo;
+
 @end
 
 @implementation ContentSuggestionsMediator
@@ -146,6 +160,10 @@ ContentSuggestionsSectionInformation* SectionInformationFromCategoryInfo(
   return dataHolders;
 }
 
+- (id<ContentSuggestionsImageFetcher>)imageFetcher {
+  return self;
+}
+
 #pragma mark - ContentSuggestionsServiceObserver
 
 - (void)contentSuggestionsService:
@@ -178,6 +196,17 @@ ContentSuggestionsSectionInformation* SectionInformationFromCategoryInfo(
   // Update dataSink.
 }
 
+#pragma mark - ContentSuggestionsImageFetcher
+
+- (void)fetchImageForSuggestion:(ContentSuggestionID*)suggestionID
+                       callback:(void (^)(const gfx::Image&))callback {
+  self.contentService->FetchSuggestionImage(
+      SuggestionIDForSectionID(
+          [self categoryWrapperForSectionInfo:suggestionID.sectionInfo],
+          suggestionID.IDInSection),
+      base::BindBlockArc(callback));
+}
+
 #pragma mark - Private
 
 - (void)addContentInCategory:(ntp_snippets::Category&)category
@@ -192,8 +221,6 @@ ContentSuggestionsSectionInformation* SectionInformationFromCategoryInfo(
     suggestion.suggestionID.sectionInfo =
         self.sectionInformationByCategory[categoryWrapper];
 
-    // TODO(crbug.com/686728): fetch the image.
-
     [contentArray addObject:suggestion];
   }
 }
@@ -209,4 +236,10 @@ ContentSuggestionsSectionInformation* SectionInformationFromCategoryInfo(
       wrapperWithCategory:category]] = sectionInfo;
 }
 
+- (ContentSuggestionsCategoryWrapper*)categoryWrapperForSectionInfo:
+    (ContentSuggestionsSectionInformation*)sectionInfo {
+  return [[self.sectionInformationByCategory allKeysForObject:sectionInfo]
+      firstObject];
+}
+
 @end