New snippets now replace old snippets and do not merge

components/ntp_snippets/category_factory.cc

 // Copyright 2016 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/category_factory.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/stringprintf.h"
 
 namespace ntp_snippets {
 
+namespace {
+
+const char kCombinedIDFormat[] = "%d|%s";
+const char kSeparator = '|';
+
+}  // namespace
+
 CategoryFactory::CategoryFactory() {
   // Add all local categories in a fixed order.
   AddKnownCategory(KnownCategories::DOWNLOADS);
   AddKnownCategory(KnownCategories::RECENT_TABS);
   AddKnownCategory(KnownCategories::FOREIGN_TABS);
   AddKnownCategory(KnownCategories::BOOKMARKS);
   AddKnownCategory(KnownCategories::PHYSICAL_WEB_PAGES);
 
   DCHECK_EQ(static_cast<size_t>(KnownCategories::LOCAL_CATEGORIES_COUNT),
             ordered_categories_.size());
@@ skipping 27 matching lines @@
 
 bool CategoryFactory::CompareCategories(const Category& left,
                                         const Category& right) const {
   if (left == right)
     return false;
   return std::find(ordered_categories_.begin(), ordered_categories_.end(),
                    left) < std::find(ordered_categories_.begin(),
                                      ordered_categories_.end(), right);
 }
 
+std::string CategoryFactory::MakeUniqueID(
+    Category category,
+    const std::string& within_category_id) const {
+  return base::StringPrintf(kCombinedIDFormat, category.id(),
+                            within_category_id.c_str());
+}
+
+Category CategoryFactory::GetCategoryFromUniqueID(
+    const std::string& unique_id) {
+  size_t colon_index = unique_id.find(kSeparator);
+  DCHECK_NE(std::string::npos, colon_index) << "Not a valid unique_id: "
+                                            << unique_id;
+  int category = -1;
+  bool ret = base::StringToInt(unique_id.substr(0, colon_index), &category);
+  DCHECK(ret) << "Non-numeric category part in unique_id: " << unique_id;
+  return FromIDValue(category);
+}
+
+std::string CategoryFactory::GetWithinCategoryIDFromUniqueID(
+    const std::string& unique_id) const {
+  size_t colon_index = unique_id.find(kSeparator);
+  DCHECK_NE(std::string::npos, colon_index) << "Not a valid unique_id: "
+                                            << unique_id;
+  return unique_id.substr(colon_index + 1);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // Private methods
 
 bool CategoryFactory::CategoryExists(int id) {
   return std::find(ordered_categories_.begin(), ordered_categories_.end(),
                    Category(id)) != ordered_categories_.end();
 }
 
 void CategoryFactory::AddKnownCategory(KnownCategories known_category) {
   InternalFromID(static_cast<int>(known_category));
 }
 
 Category CategoryFactory::InternalFromID(int id) {
   auto it = std::find(ordered_categories_.begin(), ordered_categories_.end(),
                       Category(id));
   if (it != ordered_categories_.end())
     return *it;
 
   Category category(id);
   ordered_categories_.push_back(category);
   return category;
 }
 
 }  // namespace ntp_snippets