Revert of [Suggestions] Move ImageManager to the component

chrome/browser/search/suggestions/image_manager_impl.cc

+// Copyright 2014 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 "chrome/browser/search/suggestions/image_manager_impl.h"
+
+#include "base/memory/ref_counted_memory.h"
+#include "content/public/browser/browser_thread.h"
+#include "net/base/load_flags.h"
+#include "net/url_request/url_request_context_getter.h"
+#include "ui/gfx/codec/jpeg_codec.h"
+
+using leveldb_proto::ProtoDatabase;
+
+namespace {
+
+// From JPEG-encoded bytes to SkBitmap.
+SkBitmap* DecodeImage(const std::vector<unsigned char>& encoded_data) {
+  return gfx::JPEGCodec::Decode(&encoded_data[0], encoded_data.size());
+}
+
+}  // namespace
+
+namespace suggestions {
+
+ImageManagerImpl::ImageManagerImpl() : weak_ptr_factory_(this) {}
+
+ImageManagerImpl::ImageManagerImpl(
+    net::URLRequestContextGetter* url_request_context,
+    scoped_ptr<ProtoDatabase<ImageData> > database,
+    const base::FilePath& database_dir)
+    : url_request_context_(url_request_context),
+      database_(database.Pass()),
+      database_ready_(false),
+      weak_ptr_factory_(this) {
+  database_->Init(database_dir, base::Bind(&ImageManagerImpl::OnDatabaseInit,
+                                           weak_ptr_factory_.GetWeakPtr()));
+}
+
+ImageManagerImpl::~ImageManagerImpl() {}
+
+ImageManagerImpl::ImageRequest::ImageRequest() : fetcher(NULL) {}
+
+ImageManagerImpl::ImageRequest::ImageRequest(chrome::BitmapFetcher* f)
+    : fetcher(f) {}
+
+ImageManagerImpl::ImageRequest::~ImageRequest() { delete fetcher; }
+
+void ImageManagerImpl::Initialize(const SuggestionsProfile& suggestions) {
+  image_url_map_.clear();
+  for (int i = 0; i < suggestions.suggestions_size(); ++i) {
+    const ChromeSuggestion& suggestion = suggestions.suggestions(i);
+    if (suggestion.has_thumbnail()) {
+      image_url_map_[GURL(suggestion.url())] = GURL(suggestion.thumbnail());
+    }
+  }
+}
+
+void ImageManagerImpl::GetImageForURL(
+    const GURL& url,
+    base::Callback<void(const GURL&, const SkBitmap*)> callback) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  // If |url| is not found in |image_url_map_|, then invoke |callback| with
+  // NULL since there is no associated image for this |url|.
+  GURL image_url;
+  if (!GetImageURL(url, &image_url)) {
+    callback.Run(url, NULL);
+    return;
+  }
+
+  // |database_| can be NULL if something went wrong in initialization.
+  if (database_.get() && !database_ready_) {
+    // Once database is initialized, it will serve pending requests from either
+    // cache or network.
+    QueueCacheRequest(url, image_url, callback);
+    return;
+  }
+
+  ServeFromCacheOrNetwork(url, image_url, callback);
+}
+
+bool ImageManagerImpl::GetImageURL(const GURL& url, GURL* image_url) {
+  std::map<GURL, GURL>::iterator it = image_url_map_.find(url);
+  if (it == image_url_map_.end()) return false;  // Not found.
+  *image_url = it->second;
+  return true;
+}
+
+void ImageManagerImpl::QueueCacheRequest(
+    const GURL& url, const GURL& image_url,
+    base::Callback<void(const GURL&, const SkBitmap*)> callback) {
+  // To be served when the database has loaded.
+  ImageRequestMap::iterator it = pending_cache_requests_.find(url);
+  if (it == pending_cache_requests_.end()) {
+    ImageRequest request(NULL);
+    request.url = url;
+    request.image_url = image_url;
+    request.callbacks.push_back(callback);
+    pending_cache_requests_[url].swap(&request);
+  } else {
+    // Request already queued for this url.
+    it->second.callbacks.push_back(callback);
+  }
+}
+
+void ImageManagerImpl::ServeFromCacheOrNetwork(
+    const GURL& url, const GURL& image_url,
+    base::Callback<void(const GURL&, const SkBitmap*)> callback) {
+  // If there is a image available in memory, return it.
+  if (!ServeFromCache(url, callback)) {
+    StartOrQueueNetworkRequest(url, image_url, callback);
+  }
+}
+
+bool ImageManagerImpl::ServeFromCache(
+    const GURL& url,
+    base::Callback<void(const GURL&, const SkBitmap*)> callback) {
+  SkBitmap* bitmap = GetBitmapFromCache(url);
+  if (bitmap) {
+    callback.Run(url, bitmap);
+    return true;
+  }
+  return false;
+}
+
+SkBitmap* ImageManagerImpl::GetBitmapFromCache(const GURL& url) {
+  ImageMap::iterator image_iter = image_map_.find(url.spec());
+  if (image_iter != image_map_.end()) {
+    return &image_iter->second;
+  }
+  return NULL;
+}
+
+void ImageManagerImpl::StartOrQueueNetworkRequest(
+    const GURL& url, const GURL& image_url,
+    base::Callback<void(const GURL&, const SkBitmap*)> callback) {
+  // Before starting to fetch the image. Look for a request in progress for
+  // |image_url|, and queue if appropriate.
+  ImageRequestMap::iterator it = pending_net_requests_.find(image_url);
+  if (it == pending_net_requests_.end()) {
+    // |image_url| is not being fetched, so create a request and initiate
+    // the fetch.
+    ImageRequest request(new chrome::BitmapFetcher(image_url, this));
+    request.url = url;
+    request.callbacks.push_back(callback);
+    request.fetcher->Start(
+        url_request_context_, std::string(),
+        net::URLRequest::CLEAR_REFERRER_ON_TRANSITION_FROM_SECURE_TO_INSECURE,
+        net::LOAD_NORMAL);
+    pending_net_requests_[image_url].swap(&request);
+  } else {
+    // Request in progress. Register as an interested callback.
+    it->second.callbacks.push_back(callback);
+  }
+}
+
+void ImageManagerImpl::OnFetchComplete(const GURL image_url,
+                                       const SkBitmap* bitmap) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+
+  ImageRequestMap::iterator image_iter = pending_net_requests_.find(image_url);
+  DCHECK(image_iter != pending_net_requests_.end());
+
+  ImageRequest* request = &image_iter->second;
+
+  // Here |bitmap| could be NULL or a pointer to a bitmap which is owned by the
+  // BitmapFetcher and which ceases to exist after this function. Pass the
+  // un-owned pointer to the registered callbacks.
+  for (CallbackVector::iterator callback_iter = request->callbacks.begin();
+       callback_iter != request->callbacks.end(); ++callback_iter) {
+    callback_iter->Run(request->url, bitmap);
+  }
+
+  // Save the bitmap to the in-memory model as well as the database, because it
+  // is now the freshest representation of the image.
+  // TODO(mathp): Handle null (no image found), possible deletion in DB.
+  if (bitmap) SaveImage(request->url, *bitmap);
+
+  // Erase the completed ImageRequest.
+  pending_net_requests_.erase(image_iter);
+}
+
+void ImageManagerImpl::SaveImage(const GURL& url, const SkBitmap& bitmap) {
+  // Update the image map.
+  image_map_.insert(std::make_pair(url.spec(), bitmap));
+
+  if (!database_ready_) return;
+
+  // Attempt to save a JPEG representation to the database. If not successful,
+  // the fetched bitmap will still be inserted in the cache, above.
+  std::vector<unsigned char> encoded_data;
+  if (EncodeImage(bitmap, &encoded_data)) {
+    // Save the resulting bitmap to the database.
+    ImageData data;
+    data.set_url(url.spec());
+    data.set_data(std::string(encoded_data.begin(), encoded_data.end()));
+    scoped_ptr<ProtoDatabase<ImageData>::KeyEntryVector> entries_to_save(
+        new ProtoDatabase<ImageData>::KeyEntryVector());
+    scoped_ptr<std::vector<std::string> > keys_to_remove(
+        new std::vector<std::string>());
+    entries_to_save->push_back(std::make_pair(data.url(), data));
+    database_->UpdateEntries(entries_to_save.Pass(), keys_to_remove.Pass(),
+                             base::Bind(&ImageManagerImpl::OnDatabaseSave,
+                                        weak_ptr_factory_.GetWeakPtr()));
+  }
+}
+
+void ImageManagerImpl::OnDatabaseInit(bool success) {
+  if (!success) {
+    DVLOG(1) << "Image database init failed.";
+    database_.reset();
+    ServePendingCacheRequests();
+    return;
+  }
+  database_->LoadEntries(base::Bind(&ImageManagerImpl::OnDatabaseLoad,
+                                    weak_ptr_factory_.GetWeakPtr()));
+}
+
+void ImageManagerImpl::OnDatabaseLoad(bool success,
+                                      scoped_ptr<ImageDataVector> entries) {
+  if (!success) {
+    DVLOG(1) << "Image database load failed.";
+    database_.reset();
+    ServePendingCacheRequests();
+    return;
+  }
+  database_ready_ = true;
+
+  LoadEntriesInCache(entries.Pass());
+  ServePendingCacheRequests();
+}
+
+void ImageManagerImpl::OnDatabaseSave(bool success) {
+  if (!success) {
+    DVLOG(1) << "Image database save failed.";
+    database_.reset();
+    database_ready_ = false;
+  }
+}
+
+void ImageManagerImpl::LoadEntriesInCache(scoped_ptr<ImageDataVector> entries) {
+  for (ImageDataVector::iterator it = entries->begin(); it != entries->end();
+       ++it) {
+    std::vector<unsigned char> encoded_data(it->data().begin(),
+                                            it->data().end());
+
+    scoped_ptr<SkBitmap> bitmap(DecodeImage(encoded_data));
+    if (bitmap.get()) {
+      image_map_.insert(std::make_pair(it->url(), *bitmap));
+    }
+  }
+}
+
+void ImageManagerImpl::ServePendingCacheRequests() {
+  for (ImageRequestMap::iterator it = pending_cache_requests_.begin();
+       it != pending_cache_requests_.end(); ++it) {
+    const ImageRequest& request = it->second;
+    for (CallbackVector::const_iterator callback_it = request.callbacks.begin();
+         callback_it != request.callbacks.end(); ++callback_it) {
+      ServeFromCacheOrNetwork(request.url, request.image_url, *callback_it);
+    }
+  }
+}
+
+// static
+bool ImageManagerImpl::EncodeImage(const SkBitmap& bitmap,
+                                   std::vector<unsigned char>* dest) {
+  SkAutoLockPixels bitmap_lock(bitmap);
+  if (!bitmap.readyToDraw() || bitmap.isNull()) {
+    return false;
+  }
+  return gfx::JPEGCodec::Encode(
+      reinterpret_cast<unsigned char*>(bitmap.getAddr32(0, 0)),
+      gfx::JPEGCodec::FORMAT_SkBitmap, bitmap.width(), bitmap.height(),
+      bitmap.width() * bitmap.bytesPerPixel(), 100, dest);
+}
+
+}  // namespace suggestions