// 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 "content/browser/manifest/manifest_manager_host.h"

#include "content/common/manifest_manager_messages.h"
#include "content/public/browser/render_frame_host.h"
#include "content/public/browser/render_process_host.h"
#include "content/public/common/manifest.h"
#include "content/public/common/result_codes.h"

namespace content {

namespace {

void KillRenderer(RenderFrameHost* render_frame_host) {
  base::ProcessHandle process_handle =
      render_frame_host->GetProcess()->GetHandle();
  if (process_handle == base::kNullProcessHandle)
    return;
  base::KillProcess(process_handle, RESULT_CODE_KILLED_BAD_MESSAGE, false);
}

} // anonymous namespace

ManifestManagerHost::ManifestManagerHost(WebContents* web_contents)
  : WebContentsObserver(web_contents) {
}

ManifestManagerHost::~ManifestManagerHost() {
}

ManifestManagerHost::CallbackMap* ManifestManagerHost::GetCallbackMapForFrame(
    RenderFrameHost* render_frame_host) {
  FrameCallbackMap::iterator it = pending_callbacks_.find(render_frame_host);
  return it != pending_callbacks_.end() ? it->second : 0;
}

void ManifestManagerHost::RenderFrameDeleted(
    RenderFrameHost* render_frame_host) {
  CallbackMap* callbacks = GetCallbackMapForFrame(render_frame_host);
  if (!callbacks)
    return;

  // Before deleting the callbacks, make sure they are called with a failure
  // state.
  CallbackMap::const_iterator it(callbacks);
  for (; !it.IsAtEnd(); it.Advance())
    it.GetCurrentValue()->Run(Manifest());

  pending_callbacks_.erase(render_frame_host);
}

void ManifestManagerHost::GetManifest(RenderFrameHost* render_frame_host,
                                      const GetManifestCallback& callback) {
  CallbackMap* callbacks = GetCallbackMapForFrame(render_frame_host);
  if (!callbacks) {
    callbacks = new CallbackMap();
    pending_callbacks_[render_frame_host] = callbacks;
  }

  int request_id = callbacks->Add(new GetManifestCallback(callback));

  render_frame_host->Send(new ManifestManagerMsg_RequestManifest(
      render_frame_host->GetRoutingID(), request_id));
}

bool ManifestManagerHost::OnMessageReceived(
    const IPC::Message& message, RenderFrameHost* render_frame_host) {
  bool handled = true;

  IPC_BEGIN_MESSAGE_MAP_WITH_PARAM(ManifestManagerHost, message,
                                   render_frame_host)
    IPC_MESSAGE_HANDLER(ManifestManagerHostMsg_RequestManifestResponse,
                        OnRequestManifestResponse)
    IPC_MESSAGE_UNHANDLED(handled = false)
  IPC_END_MESSAGE_MAP()

  return handled;
}

void ManifestManagerHost::OnRequestManifestResponse(
    RenderFrameHost* render_frame_host,
    int request_id,
    const Manifest& insecure_manifest) {
  CallbackMap* callbacks = GetCallbackMapForFrame(render_frame_host);
  if (!callbacks) {
    DVLOG(1) << "Unexpected RequestManifestResponse to from renderer. "
                "Killing renderer.";
    KillRenderer(render_frame_host);
    return;
  }

  GetManifestCallback* callback = callbacks->Lookup(request_id);
  if (!callback) {
    DVLOG(1) << "Received a request_id (" << request_id << ") from renderer "
                "with no associated callback. Killing renderer.";
    KillRenderer(render_frame_host);
    return;
  }

  // When receiving a Manifest, the browser process can't trust that it is
  // coming from a known and secure source. It must be processed accordingly.
  Manifest manifest = insecure_manifest;
  manifest.name = base::NullableString16(
      manifest.name.string().substr(0, Manifest::kMaxIPCStringLength),
      manifest.name.is_null());
  manifest.short_name = base::NullableString16(
        manifest.short_name.string().substr(0, Manifest::kMaxIPCStringLength),
        manifest.short_name.is_null());
  if (!manifest.start_url.is_valid())
    manifest.start_url = GURL();
  for (size_t i = 0; i < manifest.icons.size(); ++i) {
    if (!manifest.icons[i].src.is_valid())
      manifest.icons[i].src = GURL();
    manifest.icons[i].type = base::NullableString16(
        manifest.icons[i].type.string().substr(0,
                                               Manifest::kMaxIPCStringLength),
        manifest.icons[i].type.is_null());
  }

  callback->Run(manifest);
  callbacks->Remove(request_id);
  if (callbacks->IsEmpty()) {
    delete callbacks;
    pending_callbacks_.erase(render_frame_host);
  }
}

} // namespace content