Add logic for fetching the Reading List entries

components/ntp_snippets/reading_list/reading_list_suggestions_provider.cc

 // 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.
 
 #include "components/ntp_snippets/reading_list/reading_list_suggestions_provider.h"
 
 #include <vector>
 
 #include "base/bind.h"
+#include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "components/ntp_snippets/category.h"
 #include "components/reading_list/core/reading_list_entry.h"
 #include "components/reading_list/core/reading_list_model.h"
 #include "components/strings/grit/components_strings.h"
+#include "components/url_formatter/url_formatter.h"
 #include "ui/base/l10n/l10n_util.h"
 
+namespace {
+const int kMaxEntries = 3;
+}
+
 namespace ntp_snippets {
 
 ReadingListSuggestionsProvider::ReadingListSuggestionsProvider(
     ContentSuggestionsProvider::Observer* observer,
     ReadingListModel* reading_list_model)
     : ContentSuggestionsProvider(observer),
       category_status_(CategoryStatus::AVAILABLE_LOADING),
       provided_category_(
           Category::FromKnownCategory(KnownCategories::READING_LIST)),
       reading_list_model_(reading_list_model) {
   observer->OnCategoryStatusChanged(this, provided_category_, category_status_);
   reading_list_model->AddObserver(this);
-  if (reading_list_model_->loaded()) {
-    FetchReadingListInternal();
-  }
 }
 
 ReadingListSuggestionsProvider::~ReadingListSuggestionsProvider() {
   reading_list_model_->RemoveObserver(this);
 }
 
 CategoryStatus ReadingListSuggestionsProvider::GetCategoryStatus(
     Category category) {
   DCHECK_EQ(category, provided_category_);
   return category_status_;
@@ skipping 57 matching lines @@
 void ReadingListSuggestionsProvider::ClearDismissedSuggestionsForDebugging(
     Category category) {
   // TODO(crbug.com/702241): Implement this method.
 }
 
 void ReadingListSuggestionsProvider::ReadingListModelLoaded(
     const ReadingListModel* model) {
   DCHECK(model == reading_list_model_);
   FetchReadingListInternal();
 }
 

[Olivier, 2017/03/28 12:33:51]

ReadingListModelBeingDeleted() {
  reading_list_model_->RemoveObserver(this);
  reading_list_model_ = nullptr;
}

[gambard, 2017/03/28 12:55:58]

Done.

 void ReadingListSuggestionsProvider::FetchReadingListInternal() {
-  // TODO(crbug.com/702241): Implement this method.
+  std::vector<const ReadingListEntry*> entries;
+  DCHECK(reading_list_model_->loaded());
+  for (const auto& url : reading_list_model_->Keys()) {
+    const ReadingListEntry* entry = reading_list_model_->GetEntryByURL(url);
+    if (!entry->IsRead()) {
+      bool added = false;
+      for (auto it = entries.begin(); it != entries.end(); ++it) {
+        if ((*it)->UpdateTime() < entry->UpdateTime()) {
+          entries.insert(it, entry);
+          added = true;
+          break;
+        }
+      }
+      if (!added && entries.size() < kMaxEntries) {
+        entries.push_back(entry);
+      }
+      if (entries.size() > kMaxEntries) {
+        entries.pop_back();
+      }
+    }
+  }
+
+  std::vector<ContentSuggestion> suggestions;
+  for (const ReadingListEntry* entry : entries) {
+    ContentSuggestion suggestion(provided_category_, entry->URL().spec(),
+                                 entry->URL());
+    suggestion.set_title(base::UTF8ToUTF16(entry->Title()));

[Olivier, 2017/03/28 12:33:51]

What if title is empty ? Should we adopt the same logic as in ReadingListView?

[gambard, 2017/03/28 12:55:58]

Done.

+    suggestion.set_snippet_text(
+        url_formatter::FormatUrl(entry->URL().GetOrigin()));
+    suggestions.emplace_back(std::move(suggestion));
+  }
+
+  NotifyStatusChanged(CategoryStatus::AVAILABLE);
+  observer()->OnNewSuggestions(this, provided_category_,
+                               std::move(suggestions));
+}
+
+void ReadingListSuggestionsProvider::NotifyStatusChanged(
+    CategoryStatus new_status) {
+  if (category_status_ == new_status) {
+    return;
+  }
+  category_status_ = new_status;
+  observer()->OnCategoryStatusChanged(this, provided_category_, new_status);
 }
 
 }  // namespace ntp_snippets