Add PDF viewer example.

examples/pdf_viewer/pdf_viewer.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 <algorithm>
-
-#include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/message_loop/message_loop.h"
 #include "base/strings/string_tokenizer.h"
 #include "examples/bitmap_uploader/bitmap_uploader.h"
-#include "examples/media_viewer/media_viewer.mojom.h"
 #include "mojo/application/application_runner_chromium.h"
 #include "mojo/public/c/system/main.h"
 #include "mojo/public/cpp/application/application_connection.h"
 #include "mojo/public/cpp/application/application_delegate.h"
 #include "mojo/public/cpp/application/application_impl.h"
 #include "mojo/public/cpp/application/interface_factory_impl.h"
 #include "mojo/public/cpp/application/service_provider_impl.h"
 #include "mojo/services/public/cpp/view_manager/types.h"
 #include "mojo/services/public/cpp/view_manager/view.h"
 #include "mojo/services/public/cpp/view_manager/view_manager.h"
 #include "mojo/services/public/cpp/view_manager/view_manager_client_factory.h"
 #include "mojo/services/public/cpp/view_manager/view_manager_delegate.h"
 #include "mojo/services/public/cpp/view_manager/view_observer.h"
 #include "mojo/services/public/interfaces/content_handler/content_handler.mojom.h"
-#include "third_party/skia/include/core/SkColor.h"
-#include "ui/gfx/codec/png_codec.h"
+#include "mojo/services/public/interfaces/input_events/input_events.mojom.h"
+#include "mojo/services/public/interfaces/input_events/input_key_codes.mojom.h"
+#include "third_party/pdfium/fpdfsdk/include/fpdf_ext.h"
+#include "third_party/pdfium/fpdfsdk/include/fpdfformfill.h"
+#include "third_party/pdfium/fpdfsdk/include/fpdftext.h"
+#include "third_party/pdfium/fpdfsdk/include/fpdfview.h"
+#include "v8/include/v8.h"
+
+#define BACKGROUND_COLOR 0xFF888888
 
 namespace mojo {
 namespace examples {
 
-class PNGViewer;
+class PDFViewer;
 
-// TODO(aa): Hook up ZoomableMedia interface again.
-class PNGView : public ViewManagerDelegate, public ViewObserver {
+class PDFView : public ViewManagerDelegate, public ViewObserver {
  public:
   static void Spawn(URLResponsePtr response,
                     ServiceProviderImpl* exported_services,
                     scoped_ptr<ServiceProvider> imported_services,
                     Shell* shell) {
-    // PNGView deletes itself when its View is destroyed.
-    new PNGView(
+    // PDFView deletes itself when its View is destroyed.
+    new PDFView(
         response.Pass(), exported_services, imported_services.Pass(), shell);
   }
 
  private:
-  static const uint16_t kMaxZoomPercentage = 400;
-  static const uint16_t kMinZoomPercentage = 20;
-  static const uint16_t kDefaultZoomPercentage = 100;
-  static const uint16_t kZoomStep = 20;
-
-  PNGView(URLResponsePtr response,
+  PDFView(URLResponsePtr response,
           ServiceProviderImpl* exported_services,
           scoped_ptr<ServiceProvider> imported_services,
           Shell* shell)
-      : width_(0),
-        height_(0),
+      : current_page_(0),
+        page_count_(0),
+        doc_(NULL),
         imported_services_(imported_services.Pass()),
         shell_(shell),
         root_(nullptr),
-        view_manager_client_factory_(shell, this),
-        zoom_percentage_(kDefaultZoomPercentage) {
+        view_manager_client_factory_(shell, this) {
     exported_services->AddService(&view_manager_client_factory_);
-    DecodePNG(response.Pass());
+    FetchPDF(response.Pass());
   }
 
-  virtual ~PNGView() {
+  virtual ~PDFView() {
+    if (doc_)
+      FPDF_CloseDocument(doc_);
     if (root_)
       root_->RemoveObserver(this);
   }
 
   // Overridden from ViewManagerDelegate:
   virtual void OnEmbed(ViewManager* view_manager,
                        View* root,
                        ServiceProviderImpl* exported_services,
                        scoped_ptr<ServiceProvider> imported_services) override {
     root_ = root;
     root_->AddObserver(this);
     bitmap_uploader_.reset(new BitmapUploader(root_));
     bitmap_uploader_->Init(shell_);
-    bitmap_uploader_->SetColor(SK_ColorGRAY);
-    if (bitmap_.get())
-      DrawBitmap();
+    bitmap_uploader_->SetColor(BACKGROUND_COLOR);
+    DrawBitmap();
   }
 
   virtual void OnViewManagerDisconnected(ViewManager* view_manager) override {
-    // TODO(aa): Need to figure out how shutdown works.
   }
 
   // Overridden from ViewObserver:
   virtual void OnViewBoundsChanged(View* view,
                                    const Rect& old_bounds,
                                    const Rect& new_bounds) override {
     DCHECK_EQ(view, root_);
     DrawBitmap();
   }
 
+  virtual void OnViewInputEvent(View* view, const EventPtr& event) override {
+    if (event->key_data &&
+        (event->action != EVENT_TYPE_KEY_PRESSED ||
+         event->key_data->is_char)) {
+      return;
+    }
+    if ((event->key_data &&
+         event->key_data->windows_key_code == KEYBOARD_CODE_DOWN) ||
+        (event->wheel_data && event->wheel_data->y_offset < 0)) {
+      if (current_page_ < (page_count_ - 1)) {
+        current_page_++;
+        DrawBitmap();
+      }
+    } else if ((event->key_data &&
+                event->key_data->windows_key_code == KEYBOARD_CODE_UP) ||
+               (event->wheel_data && event->wheel_data->y_offset > 0)) {
+      if (current_page_ > 0) {
+        current_page_--;
+        DrawBitmap();
+      }
+    }
+  }
+
   virtual void OnViewDestroyed(View* view) override {
     DCHECK_EQ(view, root_);
     delete this;
   }
 
-  void DecodePNG(URLResponsePtr response) {
+  void DrawBitmap() {
+    if (!root_ || !doc_)
+      return;
+
+    FPDF_PAGE page = FPDF_LoadPage(doc_, current_page_);
+    FPDF_TEXTPAGE text_page = FPDFText_LoadPage(page);
+    int width = static_cast<int>(FPDF_GetPageWidth(page));
+    int height = static_cast<int>(FPDF_GetPageHeight(page));
+
+    scoped_ptr<std::vector<unsigned char>> bitmap;
+    bitmap.reset(new std::vector<unsigned char>);
+    bitmap->resize(width * height * 4);
+
+    FPDF_BITMAP f_bitmap = FPDFBitmap_CreateEx(
+        width, height, FPDFBitmap_BGRA, &(*bitmap)[0], width * 4);
+    FPDFBitmap_FillRect(f_bitmap, 0, 0, width, height, 0xFFFFFFFF);
+    FPDF_RenderPageBitmap(f_bitmap, page, 0, 0, width, height, 0, 0);
+    FPDFBitmap_Destroy(f_bitmap);
+
+    FPDFText_ClosePage(text_page);
+    FPDF_ClosePage(page);
+
+    bitmap_uploader_->SetBitmap(width, height, bitmap.Pass(),
+                                BitmapUploader::BGRA);
+  }
+
+  void FetchPDF(URLResponsePtr response) {
     int content_length = GetContentLength(response->headers);
-    scoped_ptr<unsigned char[]> data(new unsigned char[content_length]);
-    unsigned char* buf = data.get();
+    scoped_ptr<unsigned char[]> data;
+    data_.reset(new unsigned char[content_length]);
+    unsigned char* buf = data_.get();
     uint32_t bytes_remaining = content_length;
     uint32_t num_bytes = bytes_remaining;
     while (bytes_remaining > 0) {
       MojoResult result = ReadDataRaw(
           response->body.get(), buf, &num_bytes, MOJO_READ_DATA_FLAG_NONE);
       if (result == MOJO_RESULT_SHOULD_WAIT) {
         Wait(response->body.get(),
              MOJO_HANDLE_SIGNAL_READABLE,
              MOJO_DEADLINE_INDEFINITE);
       } else if (result == MOJO_RESULT_OK) {
         buf += num_bytes;
         num_bytes = bytes_remaining -= num_bytes;
       } else {
         break;
       }
     }
 
-    bitmap_.reset(new std::vector<unsigned char>);
-    gfx::PNGCodec::Decode(static_cast<const unsigned char*>(data.get()),
-                          content_length,
-                          gfx::PNGCodec::FORMAT_BGRA,
-                          bitmap_.get(),
-                          &width_,
-                          &height_);
-  }
-
-  void DrawBitmap() {
-    if (!root_)
-      return;
-
-
-    bitmap_uploader_->SetBitmap(width_, height_, bitmap_.Pass(),
-                                BitmapUploader::BGRA);
-  }
-
-  void ZoomIn() {
-    if (zoom_percentage_ >= kMaxZoomPercentage)
-      return;
-    zoom_percentage_ += kZoomStep;
-    DrawBitmap();
-  }
-
-  void ZoomOut() {
-    if (zoom_percentage_ <= kMinZoomPercentage)
-      return;
-    zoom_percentage_ -= kZoomStep;
-    DrawBitmap();
-  }
-
-  void ZoomToActualSize() {
-    if (zoom_percentage_ == kDefaultZoomPercentage)
-      return;
-    zoom_percentage_ = kDefaultZoomPercentage;
-    DrawBitmap();
+    doc_ = FPDF_LoadMemDocument(data_.get(), content_length, NULL);
+    page_count_ = FPDF_GetPageCount(doc_);
   }
 
   int GetContentLength(const Array<String>& headers) {
     for (size_t i = 0; i < headers.size(); ++i) {
       base::StringTokenizer t(headers[i], ": ;=");
       while (t.GetNext()) {
         if (!t.token_is_delim() && t.token() == "Content-Length") {
           while (t.GetNext()) {
             if (!t.token_is_delim())
               return atoi(t.token().c_str());
           }
         }
       }
     }
     return 0;
   }
 
-  int width_;
-  int height_;
-  scoped_ptr<std::vector<unsigned char>> bitmap_;
+  scoped_ptr<unsigned char[]> data_;
+  int current_page_;
+  int page_count_;
+  FPDF_DOCUMENT doc_;
   scoped_ptr<ServiceProvider> imported_services_;
   Shell* shell_;
   View* root_;
   ViewManagerClientFactory view_manager_client_factory_;
-  uint16_t zoom_percentage_;
   scoped_ptr<BitmapUploader> bitmap_uploader_;
 
-  DISALLOW_COPY_AND_ASSIGN(PNGView);
+  DISALLOW_COPY_AND_ASSIGN(PDFView);
 };
 
 class ContentHandlerImpl : public InterfaceImpl<ContentHandler> {
  public:
   explicit ContentHandlerImpl(Shell* shell) : shell_(shell) {}
   virtual ~ContentHandlerImpl() {}
 
  private:
   // Overridden from ContentHandler:
   virtual void OnConnect(
       const mojo::String& requestor_url,
       URLResponsePtr response,
       InterfaceRequest<ServiceProvider> service_provider) override {
     ServiceProviderImpl* exported_services = new ServiceProviderImpl();
     BindToRequest(exported_services, &service_provider);
     scoped_ptr<ServiceProvider> remote(
         exported_services->CreateRemoteServiceProvider());
-    PNGView::Spawn(response.Pass(), exported_services, remote.Pass(), shell_);
+    PDFView::Spawn(response.Pass(), exported_services, remote.Pass(), shell_);
   }
 
   Shell* shell_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentHandlerImpl);
 };
 
-class PNGViewer : public ApplicationDelegate {
+class PDFViewer : public ApplicationDelegate {
  public:
-  PNGViewer() {}
+  PDFViewer() {}
+  virtual ~PDFViewer() {
+    FPDF_DestroyLibrary();
+  }
  private:
   // Overridden from ApplicationDelegate:
   virtual void Initialize(ApplicationImpl* app) override {
     content_handler_factory_.reset(
         new InterfaceFactoryImplWithContext<ContentHandlerImpl, Shell>(
             app->shell()));
+
+    v8::V8::InitializeICU();
+    FPDF_InitLibrary(NULL);
   }
 
   // Overridden from ApplicationDelegate:
   virtual bool ConfigureIncomingConnection(
       ApplicationConnection* connection) override {
     connection->AddService(content_handler_factory_.get());
     return true;
   }
 
   scoped_ptr<InterfaceFactoryImplWithContext<ContentHandlerImpl, Shell> >
       content_handler_factory_;
 
-  DISALLOW_COPY_AND_ASSIGN(PNGViewer);
+  DISALLOW_COPY_AND_ASSIGN(PDFViewer);
 };
 
 }  // namespace examples
 }  // namespace mojo
 
 MojoResult MojoMain(MojoHandle shell_handle) {
-  mojo::ApplicationRunnerChromium runner(new mojo::examples::PNGViewer);
+  mojo::ApplicationRunnerChromium runner(new mojo::examples::PDFViewer);
   return runner.Run(shell_handle);
 }