// Copyright (c) 2013 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 "cc/output/output_surface.h"

#include <stdint.h>

#include "base/bind.h"
#include "base/location.h"
#include "base/macros.h"
#include "base/single_thread_task_runner.h"
#include "base/thread_task_runner_handle.h"
#include "base/trace_event/trace_event.h"
#include "cc/output/managed_memory_policy.h"
#include "cc/output/output_surface_client.h"
#include "gpu/GLES2/gl2extchromium.h"
#include "gpu/command_buffer/client/context_support.h"
#include "gpu/command_buffer/client/gles2_interface.h"
#include "third_party/skia/include/core/SkTraceMemoryDump.h"
#include "third_party/skia/include/gpu/GrContext.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gl/trace_util.h"

class SkDiscardableMemory;

namespace cc {

namespace {

// Constants used by SkiaGpuTraceMemoryDump to identify different memory types.
const char* kGLTextureBackingType = "gl_texture";
const char* kGLBufferBackingType = "gl_buffer";
const char* kGLRenderbufferBackingType = "gl_renderbuffer";

// Derives from SkTraceMemoryDump and implements graphics specific memory
// backing functionality.
class SkiaGpuTraceMemoryDump : public SkTraceMemoryDump {
 public:
  // This should never outlive the provided ProcessMemoryDump, as it should
  // always be scoped to a single OnMemoryDump funciton call.
  explicit SkiaGpuTraceMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
                                  uint64_t share_group_tracing_guid)
      : pmd_(pmd), share_group_tracing_guid_(share_group_tracing_guid) {}

  // Overridden from SkTraceMemoryDump:
  void dumpNumericValue(const char* dump_name,
                        const char* value_name,
                        const char* units,
                        uint64_t value) override {
    auto dump = GetOrCreateAllocatorDump(dump_name);
    dump->AddScalar(value_name, units, value);
  }

  void setMemoryBacking(const char* dump_name,
                        const char* backing_type,
                        const char* backing_object_id) override {
    const uint64_t tracing_process_id =
        base::trace_event::MemoryDumpManager::GetInstance()
            ->GetTracingProcessId();

    // For uniformity, skia provides this value as a string. Convert back to a
    // uint32_t.
    uint32_t gl_id =
        std::strtoul(backing_object_id, nullptr /* str_end */, 10 /* base */);

    // Populated in if statements below.
    base::trace_event::MemoryAllocatorDumpGuid guid;

    if (strcmp(backing_type, kGLTextureBackingType) == 0) {
      guid = gfx::GetGLTextureClientGUIDForTracing(share_group_tracing_guid_,
                                                   gl_id);
    } else if (strcmp(backing_type, kGLBufferBackingType) == 0) {
      guid = gfx::GetGLBufferGUIDForTracing(tracing_process_id, gl_id);
    } else if (strcmp(backing_type, kGLRenderbufferBackingType) == 0) {
      guid = gfx::GetGLRenderbufferGUIDForTracing(tracing_process_id, gl_id);
    }

    if (!guid.empty()) {
      pmd_->CreateSharedGlobalAllocatorDump(guid);

      auto* dump = GetOrCreateAllocatorDump(dump_name);

      const int kImportance = 2;
      pmd_->AddOwnershipEdge(dump->guid(), guid, kImportance);
    }
  }

  void setDiscardableMemoryBacking(
      const char* dump_name,
      const SkDiscardableMemory& discardable_memory_object) override {
    // We don't use this class for dumping discardable memory.
    NOTREACHED();
  }

  LevelOfDetail getRequestedDetails() const override {
    // TODO(ssid): Use MemoryDumpArgs to create light dumps when requested
    // (crbug.com/499731).
    return kObjectsBreakdowns_LevelOfDetail;
  }

 private:
  // Helper to create allocator dumps.
  base::trace_event::MemoryAllocatorDump* GetOrCreateAllocatorDump(
      const char* dump_name) {
    auto dump = pmd_->GetAllocatorDump(dump_name);
    if (!dump)
      dump = pmd_->CreateAllocatorDump(dump_name);
    return dump;
  }

  base::trace_event::ProcessMemoryDump* pmd_;
  uint64_t share_group_tracing_guid_;

  DISALLOW_COPY_AND_ASSIGN(SkiaGpuTraceMemoryDump);
};

}  // namespace

OutputSurface::OutputSurface(
    const scoped_refptr<ContextProvider>& context_provider,
    const scoped_refptr<ContextProvider>& worker_context_provider,
    scoped_ptr<SoftwareOutputDevice> software_device)
    : client_(NULL),
      context_provider_(context_provider),
      worker_context_provider_(worker_context_provider),
      software_device_(std::move(software_device)),
      device_scale_factor_(-1),
      has_alpha_(true),
      external_stencil_test_enabled_(false),
      weak_ptr_factory_(this) {
  client_thread_checker_.DetachFromThread();
}

OutputSurface::OutputSurface(
    const scoped_refptr<ContextProvider>& context_provider)
    : OutputSurface(context_provider, nullptr, nullptr) {
}

OutputSurface::OutputSurface(
    const scoped_refptr<ContextProvider>& context_provider,
    const scoped_refptr<ContextProvider>& worker_context_provider)
    : OutputSurface(context_provider, worker_context_provider, nullptr) {
}

OutputSurface::OutputSurface(scoped_ptr<SoftwareOutputDevice> software_device)
    : OutputSurface(nullptr, nullptr, std::move(software_device)) {}

OutputSurface::OutputSurface(
    const scoped_refptr<ContextProvider>& context_provider,
    scoped_ptr<SoftwareOutputDevice> software_device)
    : OutputSurface(context_provider, nullptr, std::move(software_device)) {}

void OutputSurface::CommitVSyncParameters(base::TimeTicks timebase,
                                          base::TimeDelta interval) {
  TRACE_EVENT2("cc",
               "OutputSurface::CommitVSyncParameters",
               "timebase",
               (timebase - base::TimeTicks()).InSecondsF(),
               "interval",
               interval.InSecondsF());
  client_->CommitVSyncParameters(timebase, interval);
}

// Forwarded to OutputSurfaceClient
void OutputSurface::SetNeedsRedrawRect(const gfx::Rect& damage_rect) {
  TRACE_EVENT0("cc", "OutputSurface::SetNeedsRedrawRect");
  client_->SetNeedsRedrawRect(damage_rect);
}

void OutputSurface::ReclaimResources(const CompositorFrameAck* ack) {
  client_->ReclaimResources(ack);
}

void OutputSurface::DidLoseOutputSurface() {
  TRACE_EVENT0("cc", "OutputSurface::DidLoseOutputSurface");
  client_->DidLoseOutputSurface();
}

void OutputSurface::SetExternalStencilTest(bool enabled) {
  external_stencil_test_enabled_ = enabled;
}

OutputSurface::~OutputSurface() {
  if (client_)
    DetachFromClientInternal();
}

bool OutputSurface::HasExternalStencilTest() const {
  return external_stencil_test_enabled_;
}

void OutputSurface::ApplyExternalStencil() {}

bool OutputSurface::BindToClient(OutputSurfaceClient* client) {
  DCHECK(client_thread_checker_.CalledOnValidThread());
  DCHECK(client);
  DCHECK(!client_);
  client_ = client;
  bool success = true;

  if (context_provider_.get()) {
    success = context_provider_->BindToCurrentThread();
    if (success) {
      context_provider_->SetLostContextCallback(base::Bind(
          &OutputSurface::DidLoseOutputSurface, base::Unretained(this)));
    }
  }

  if (!success)
    client_ = NULL;

  // In certain cases, ThreadTaskRunnerHandle isn't set (Android Webview).
  // Don't register a dump provider in these cases.
  // TODO(ericrk): Get this working in Android Webview. crbug.com/517156
  if (client_ && base::ThreadTaskRunnerHandle::IsSet()) {
    // Now that we are on the context thread, register a dump provider with this
    // thread's task runner. This will overwrite any previous dump provider
    // registered.
    base::trace_event::MemoryDumpManager::GetInstance()->RegisterDumpProvider(
        this, "OutputSurface", base::ThreadTaskRunnerHandle::Get());
  }

  return success;
}

void OutputSurface::DetachFromClient() {
  DetachFromClientInternal();
}

void OutputSurface::EnsureBackbuffer() {
  if (software_device_)
    software_device_->EnsureBackbuffer();
}

void OutputSurface::DiscardBackbuffer() {
  if (context_provider_.get())
    context_provider_->ContextGL()->DiscardBackbufferCHROMIUM();
  if (software_device_)
    software_device_->DiscardBackbuffer();
}

void OutputSurface::Reshape(const gfx::Size& size,
                            float scale_factor,
                            bool has_alpha) {
  if (size == surface_size_ && scale_factor == device_scale_factor_ &&
      has_alpha == has_alpha_)
    return;

  surface_size_ = size;
  device_scale_factor_ = scale_factor;
  has_alpha_ = has_alpha;
  if (context_provider_.get()) {
    context_provider_->ContextGL()->ResizeCHROMIUM(size.width(), size.height(),
                                                   scale_factor, has_alpha);
  }
  if (software_device_)
    software_device_->Resize(size, scale_factor);
}

void OutputSurface::BindFramebuffer() {
  DCHECK(context_provider_.get());
  context_provider_->ContextGL()->BindFramebuffer(GL_FRAMEBUFFER, 0);
}

void OutputSurface::PostSwapBuffersComplete() {
  base::ThreadTaskRunnerHandle::Get()->PostTask(
      FROM_HERE, base::Bind(&OutputSurface::OnSwapBuffersComplete,
                            weak_ptr_factory_.GetWeakPtr()));
}

// We don't post tasks bound to the client directly since they might run
// after the OutputSurface has been destroyed.
void OutputSurface::OnSwapBuffersComplete() {
  client_->DidSwapBuffersComplete();
}

void OutputSurface::SetMemoryPolicy(const ManagedMemoryPolicy& policy) {
  TRACE_EVENT1("cc", "OutputSurface::SetMemoryPolicy",
               "bytes_limit_when_visible", policy.bytes_limit_when_visible);
  // Just ignore the memory manager when it says to set the limit to zero
  // bytes. This will happen when the memory manager thinks that the renderer
  // is not visible (which the renderer knows better).
  if (policy.bytes_limit_when_visible)
    client_->SetMemoryPolicy(policy);
}

OverlayCandidateValidator* OutputSurface::GetOverlayCandidateValidator() const {
  return nullptr;
}

bool OutputSurface::IsDisplayedAsOverlayPlane() const {
  return false;
}

unsigned OutputSurface::GetOverlayTextureId() const {
  return 0;
}

void OutputSurface::SetWorkerContextShouldAggressivelyFreeResources(
    bool aggressively_free_resources) {
  TRACE_EVENT1("cc",
               "OutputSurface::SetWorkerContextShouldAggressivelyFreeResources",
               "aggressively_free_resources", aggressively_free_resources);
  if (auto* context_provider = worker_context_provider()) {
    ContextProvider::ScopedContextLock scoped_context(context_provider);

    if (aggressively_free_resources) {
      context_provider->DeleteCachedResources();
    }

    if (auto* context_support = context_provider->ContextSupport()) {
      context_support->SetAggressivelyFreeResources(
          aggressively_free_resources);
    }
  }
}

bool OutputSurface::SurfaceIsSuspendForRecycle() const {
  return false;
}

bool OutputSurface::OnMemoryDump(const base::trace_event::MemoryDumpArgs& args,
                                 base::trace_event::ProcessMemoryDump* pmd) {
  if (auto* context_provider = this->context_provider()) {
    // No need to lock, main context provider is not shared.
    if (auto* gr_context = context_provider->GrContext()) {
      SkiaGpuTraceMemoryDump trace_memory_dump(
          pmd, context_provider->ContextSupport()->ShareGroupTracingGUID());
      gr_context->dumpMemoryStatistics(&trace_memory_dump);
    }
  }
  if (auto* context_provider = worker_context_provider()) {
    ContextProvider::ScopedContextLock scoped_context(context_provider);

    if (auto* gr_context = context_provider->GrContext()) {
      SkiaGpuTraceMemoryDump trace_memory_dump(
          pmd, context_provider->ContextSupport()->ShareGroupTracingGUID());
      gr_context->dumpMemoryStatistics(&trace_memory_dump);
    }
  }

  return true;
}

void OutputSurface::DetachFromClientInternal() {
  DCHECK(client_thread_checker_.CalledOnValidThread());
  DCHECK(client_);

  // Unregister any dump provider. Safe to call (no-op) if we have not yet
  // registered.
  base::trace_event::MemoryDumpManager::GetInstance()->UnregisterDumpProvider(
      this);

  if (context_provider_.get()) {
    context_provider_->SetLostContextCallback(
        ContextProvider::LostContextCallback());
  }
  context_provider_ = nullptr;
  client_ = nullptr;
  weak_ptr_factory_.InvalidateWeakPtrs();
}

}  // namespace cc