[Suggested files] Create search results from ItemSuggestCache.

The steps involved are:
 1. Get some results from the cache
 2. Run them through LocateFilesByItemIds to convert item IDs into
    file paths
 3. Assign relevance scores and create FileResult objects.

Bug: 1034842
Change-Id: If217d5eb5645e9a5eefa8a57609d9ea91014db4b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2434108Reviewed-by: Rachel Wong <wrong@chromium.org>
Commit-Queue: Tony Yeoman <tby@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811122}

chrome/browser/ui/BUILD.gn

@@ -2574,6 +2574,7 @@ static_library("ui") {
       "//chromeos/components/bloom/public/cpp:bloom_controller_factory",
       "//chromeos/components/camera_app_ui",
       "//chromeos/components/diagnostics_ui",
+      "//chromeos/components/drivefs/mojom:mojom",
       "//chromeos/components/help_app_ui",
       "//chromeos/components/local_search_service:local_search_service",
       "//chromeos/components/media_app_ui",

chrome/browser/ui/app_list/search/files/drive_zero_state_provider.cc

@@ -9,6 +9,7 @@
 #include <utility>
 
 #include "ash/public/cpp/app_list/app_list_features.h"
+#include "ash/public/cpp/app_list/app_list_types.h"
 #include "base/bind.h"
 #include "base/files/file_util.h"
 #include "base/metrics/histogram_macros.h"
@@ -17,14 +18,18 @@
 #include "base/task/thread_pool.h"
 #include "base/task_runner_util.h"
 #include "chrome/browser/chromeos/drive/drive_integration_service.h"
-#include "chrome/browser/ui/app_list/search/drive_quick_access_chip_result.h"
-#include "chrome/browser/ui/app_list/search/drive_quick_access_result.h"
 #include "chrome/browser/ui/app_list/search/search_controller.h"
+#include "components/drive/file_errors.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_task_traits.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace app_list {
+namespace {
+
+constexpr char kSchema[] = "drive_zero_state://";
+
+}
 
 DriveZeroStateProvider::DriveZeroStateProvider(
     Profile* profile,
@@ -33,6 +38,8 @@ DriveZeroStateProvider::DriveZeroStateProvider(
     : profile_(profile),
       drive_service_(
           drive::DriveIntegrationServiceFactory::GetForProfile(profile)),
+      file_tasks_notifier_(
+          file_manager::file_tasks::FileTasksNotifier::GetForProfile(profile)),
       item_suggest_cache_(profile, std::move(url_loader_factory)),
       suggested_files_enabled_(app_list_features::IsSuggestedFilesEnabled()) {
   DCHECK(profile_);
@@ -54,6 +61,12 @@ void DriveZeroStateProvider::OnFileSystemMounted() {
   // results for this search provider.
 }
 
+void DriveZeroStateProvider::AppListShown() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  item_suggest_cache_.UpdateCache();
+  // TODO(crbug.com/1034842): Query ItemSuggest, consider rate-limiting.
+}
+
 ash::AppListSearchResultType DriveZeroStateProvider::ResultType() {
   return ash::AppListSearchResultType::kDriveQuickAccess;
 }
@@ -61,16 +74,75 @@ ash::AppListSearchResultType DriveZeroStateProvider::ResultType() {
 void DriveZeroStateProvider::Start(const base::string16& query) {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   ClearResultsSilently();
-  if (!query.empty())
+
+  // TODO(crbug.com/1034842): Add query latency metrics.
+
+  // Exit in three cases:
+  //  - this search has a non-empty query, we only handle zero-state.
+  //  - drive fs isn't mounted, as we launch results via drive fs.
+  //  - the |file_tasks_notifier_| is unavailable, as we stat files using it.
+  const bool drive_fs_mounted = drive_service_ && drive_service_->IsMounted();
+  if (!query.empty() || !drive_fs_mounted || !file_tasks_notifier_) {
+    return;
+  }
+
+  // Cancel any in-flight queries for this provider.
+  weak_factory_.InvalidateWeakPtrs();
+
+  // Get the most recent results from the cache.
+  cache_results_ = item_suggest_cache_.GetResults();
+  if (!cache_results_)
     return;
 
-  // TODO(crbug.com/1034842): Convert results cache into search results.
+  std::vector<std::string> item_ids;
+  for (const auto& result : cache_results_->results) {
+    item_ids.push_back(result.id);
+  }
+
+  drive_service_->LocateFilesByItemIds(
+      item_ids, base::BindOnce(&DriveZeroStateProvider::OnFilePathsLocated,
+                               weak_factory_.GetWeakPtr()));
 }
 
-void DriveZeroStateProvider::AppListShown() {
-  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-  item_suggest_cache_.UpdateCache();
-  // TODO(crbug.com/1034842): Query ItemSuggest, consider rate-limiting.
+void DriveZeroStateProvider::OnFilePathsLocated(
+    base::Optional<std::vector<drivefs::mojom::FilePathOrErrorPtr>> paths) {
+  if (!paths)
+    return;
+  DCHECK(cache_results_);
+  DCHECK_EQ(cache_results_->results.size(), paths->size());
+
+  // Assign scores to results by simply using their position in the results
+  // list. The order of results from the ItemSuggest API is significant:
+  // the first is better than the second, etc. Resulting scores are in [0, 1].
+  const double total_items = static_cast<double>(paths->size());
+  int item_index = 0;
+  SearchProvider::Results provider_results;
+  for (int i = 0; i < static_cast<int>(paths->size()); ++i) {
+    if ((*paths)[i]->get_error() != drive::FILE_ERROR_OK)
+      continue;
+
+    const double score = 1.0 - (item_index / total_items);
+    ++item_index;
+
+    // TODO(crbug.com/1034842): Use |cache_results_| to attach the session id to
+    // the result.
+    provider_results.emplace_back(
+        MakeResult((*paths)[i]->get_path(), score, /*is_chip=*/false));
+  }
+
+  cache_results_.reset();
+  SwapResults(&provider_results);
+}
+
+std::unique_ptr<FileResult> DriveZeroStateProvider::MakeResult(
+    const base::FilePath& filepath,
+    const float relevance,
+    const bool is_chip) {
+  return std::make_unique<FileResult>(
+      kSchema, filepath, ash::AppListSearchResultType::kDriveQuickAccessChip,
+      is_chip ? ash::SearchResultDisplayType::kChip
+              : ash::SearchResultDisplayType::kList,
+      relevance, profile_);
 }
 
 }  // namespace app_list

chrome/browser/ui/app_list/search/files/drive_zero_state_provider.h

@@ -15,8 +15,10 @@
 #include "base/time/time.h"
 #include "chrome/browser/chromeos/drive/drive_integration_service.h"
 #include "chrome/browser/chromeos/file_manager/file_tasks_notifier.h"
+#include "chrome/browser/ui/app_list/search/files/file_result.h"
 #include "chrome/browser/ui/app_list/search/files/item_suggest_cache.h"
 #include "chrome/browser/ui/app_list/search/search_provider.h"
+#include "chromeos/components/drivefs/mojom/drivefs.mojom.h"
 
 class Profile;
 
@@ -36,20 +38,33 @@ class DriveZeroStateProvider : public SearchProvider,
   DriveZeroStateProvider(const DriveZeroStateProvider&) = delete;
   DriveZeroStateProvider& operator=(const DriveZeroStateProvider&) = delete;
 
+  // drive::DriveIntegrationServiceObserver:
+  void OnFileSystemMounted() override;
+
   // SearchProvider:
-  void Start(const base::string16& query) override;
   void AppListShown() override;
   ash::AppListSearchResultType ResultType() override;
-
-  // drive::DriveIntegrationServiceObserver:
-  void OnFileSystemMounted() override;
+  void Start(const base::string16& query) override;
 
  private:
+  void OnFilePathsLocated(
+      base::Optional<std::vector<drivefs::mojom::FilePathOrErrorPtr>> paths);
+
+  std::unique_ptr<FileResult> MakeResult(const base::FilePath& filepath,
+                                         const float relevance,
+                                         const bool is_chip);
+
   Profile* const profile_;
   drive::DriveIntegrationService* const drive_service_;
+  file_manager::file_tasks::FileTasksNotifier* const file_tasks_notifier_;
 
   ItemSuggestCache item_suggest_cache_;
 
+  // The most recent results retrieved from |item_suggested_cache_|. This is
+  // updated on a call to Start and is used only to store the results until
+  // OnFilePathsLocated has finished.
+  base::Optional<ItemSuggestCache::Results> cache_results_;
+
   // Whether the suggested files experiment is enabled.
   const bool suggested_files_enabled_;
 

chrome/browser/ui/app_list/search/files/item_suggest_cache.cc

@@ -208,6 +208,12 @@ ItemSuggestCache::ItemSuggestCache(
 
 ItemSuggestCache::~ItemSuggestCache() = default;
 
+base::Optional<ItemSuggestCache::Results> ItemSuggestCache::GetResults() {
+  // Return a copy because a pointer to |results_| will become invalid whenever
+  // the cache is updated.
+  return results_;
+}
+
 void ItemSuggestCache::UpdateCache() {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   // TODO(crbug.com/1034842): Add rate-limiting for cache updates.

chrome/browser/ui/app_list/search/files/item_suggest_cache.h

@@ -59,6 +59,10 @@ class ItemSuggestCache {
   ItemSuggestCache(const ItemSuggestCache&) = delete;
   ItemSuggestCache& operator=(const ItemSuggestCache&) = delete;
 
+  // Returns the results currently in the cache.
+  base::Optional<ItemSuggestCache::Results> GetResults();
+
+  // Updates the cache by calling ItemSuggest.
   void UpdateCache();
 
   static base::Optional<ItemSuggestCache::Results> ConvertJsonForTest(