/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set expandtab ts=2 sw=2 sts=2 cin: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "AppProtocolHandler.h"
#include "nsBaseChannel.h"
#include "nsJARChannel.h"
#include "nsNetCID.h"
#include "nsNetUtil.h"
#include "nsIStandardURL.h"
#include "nsIAppsService.h"
#include "nsILoadInfo.h"
#include "nsXULAppAPI.h"
#include "nsPrincipal.h"
#include "nsContentSecurityManager.h"

#include "mozilla/dom/ScriptSettings.h"
#include "mozilla/Preferences.h"

using namespace mozilla;

/**
  * This dummy channel implementation only provides enough functionality
  * to return a fake 404 error when the caller asks for an app:// URL
  * containing an unknown appId.
  */
class DummyChannel : public nsIJARChannel
                          , nsRunnable
{
public:
  NS_DECL_ISUPPORTS_INHERITED
  NS_DECL_NSIREQUEST
  NS_DECL_NSICHANNEL
  NS_DECL_NSIJARCHANNEL

  DummyChannel();

  NS_IMETHODIMP Run() override;

private:
  ~DummyChannel() {}

  bool                        mPending;
  uint32_t                    mSuspendCount;
  nsCOMPtr<nsISupports>       mListenerContext;
  nsCOMPtr<nsIStreamListener> mListener;
  nsCOMPtr<nsILoadGroup>      mLoadGroup;
  nsLoadFlags                 mLoadFlags;
  nsCOMPtr<nsILoadInfo>       mLoadInfo;
};

NS_IMPL_ISUPPORTS_INHERITED(DummyChannel, nsRunnable, nsIRequest, nsIChannel, nsIJARChannel)

DummyChannel::DummyChannel() : mPending(false)
                             , mSuspendCount(0)
                             , mLoadFlags(LOAD_NORMAL)
{
}

NS_IMETHODIMP DummyChannel::GetName(nsACString &result)
{
  result = "dummy_app_channel";
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::GetStatus(nsresult *aStatus)
{
  *aStatus = NS_ERROR_FILE_NOT_FOUND;
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::IsPending(bool *aResult)
{
  *aResult = mPending;
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::Suspend()
{
  mSuspendCount++;
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::Resume()
{
  if (mSuspendCount <= 0) {
    return NS_ERROR_UNEXPECTED;
  }

  if (--mSuspendCount == 0) {
    NS_DispatchToMainThread(this, NS_DISPATCH_NORMAL);
  }
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::Open(nsIInputStream**)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
DummyChannel::Open2(nsIInputStream** aStream)
{
  nsCOMPtr<nsIStreamListener> listener;
  nsresult rv = nsContentSecurityManager::doContentSecurityCheck(this, listener);
  NS_ENSURE_SUCCESS(rv, rv);
  return Open(aStream);
}

NS_IMETHODIMP DummyChannel::AsyncOpen(nsIStreamListener* aListener, nsISupports* aContext)
{
  MOZ_ASSERT(!mLoadInfo ||
             mLoadInfo->GetSecurityMode() == 0 ||
             mLoadInfo->GetInitialSecurityCheckDone() ||
             (mLoadInfo->GetSecurityMode() == nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_DATA_IS_NULL &&
              nsContentUtils::IsSystemPrincipal(mLoadInfo->LoadingPrincipal())),
             "security flags in loadInfo but asyncOpen2() not called");

  mListener = aListener;
  mListenerContext = aContext;
  mPending = true;

  if (mLoadGroup) {
    mLoadGroup->AddRequest(this, aContext);
  }

  if (mSuspendCount == 0) {
    NS_DispatchToMainThread(this, NS_DISPATCH_NORMAL);
  }

  return NS_OK;
}

NS_IMETHODIMP
DummyChannel::AsyncOpen2(nsIStreamListener* aListener)
{
  nsCOMPtr<nsIStreamListener> listener = aListener;
  nsresult rv = nsContentSecurityManager::doContentSecurityCheck(this, listener);
  NS_ENSURE_SUCCESS(rv, rv);
  return AsyncOpen(listener, nullptr);
}

// nsIJarChannel, needed for XHR to turn NS_ERROR_FILE_NOT_FOUND into
// a 404 error.
NS_IMETHODIMP DummyChannel::GetIsUnsafe(bool *aResult)
{
  *aResult = false;
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::SetAppURI(nsIURI *aURI)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetJarFile(nsIFile* *aFile)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetZipEntry(nsIZipEntry* *aEntry)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::Run()
{
  nsresult rv = mListener->OnStartRequest(this, mListenerContext);
  mPending = false;
  rv = mListener->OnStopRequest(this, mListenerContext, NS_ERROR_FILE_NOT_FOUND);
  if (mLoadGroup) {
    mLoadGroup->RemoveRequest(this, mListenerContext, NS_ERROR_FILE_NOT_FOUND);
  }

  mListener = nullptr;
  mListenerContext = nullptr;
  rv = SetNotificationCallbacks(nullptr);
  NS_ENSURE_SUCCESS(rv, rv);

  return NS_OK;
}

NS_IMETHODIMP DummyChannel::Cancel(nsresult)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetLoadGroup(nsILoadGroup* *aLoadGroup)
{
  *aLoadGroup = mLoadGroup;
  NS_IF_ADDREF(*aLoadGroup);
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::SetLoadGroup(nsILoadGroup* aLoadGroup)
{
  mLoadGroup = aLoadGroup;
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::GetLoadFlags(nsLoadFlags *aLoadFlags)
{
  *aLoadFlags = mLoadFlags;
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::SetLoadFlags(nsLoadFlags aLoadFlags)
{
  mLoadFlags = aLoadFlags;
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::GetOriginalURI(nsIURI**)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::SetOriginalURI(nsIURI*)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetOwner(nsISupports**)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::SetOwner(nsISupports*)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetLoadInfo(nsILoadInfo** aLoadInfo)
{
  NS_IF_ADDREF(*aLoadInfo = mLoadInfo);
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::SetLoadInfo(nsILoadInfo* aLoadInfo)
{
  mLoadInfo = aLoadInfo;
  return NS_OK;
}

NS_IMETHODIMP DummyChannel::GetNotificationCallbacks(nsIInterfaceRequestor**)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::SetNotificationCallbacks(nsIInterfaceRequestor*)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetSecurityInfo(nsISupports**)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetContentType(nsACString&)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::SetContentType(const nsACString&)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetContentCharset(nsACString&)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::SetContentCharset(const nsACString&)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetContentLength(int64_t*)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::SetContentLength(int64_t)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetContentDisposition(uint32_t*)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::SetContentDisposition(uint32_t)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetURI(nsIURI**)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetContentDispositionFilename(nsAString&)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::SetContentDispositionFilename(nsAString const &)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP DummyChannel::GetContentDispositionHeader(nsACString&)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

/**
  * app:// protocol implementation.
  */

AppProtocolHandler::AppProtocolHandler() {
}

AppProtocolHandler::~AppProtocolHandler() {
  mAppInfoCache.Clear();
}

NS_IMPL_ISUPPORTS(AppProtocolHandler, nsIProtocolHandler)

/* static */
nsresult
AppProtocolHandler::Create(nsISupports* aOuter,
                           const nsIID& aIID,
                           void* *aResult)
{
  // Instantiate the service here since that intializes gJarHandler, which we
  // use indirectly (via our new JarChannel) in NewChannel.
  nsCOMPtr<nsIProtocolHandler> jarInitializer(
    do_GetService(NS_NETWORK_PROTOCOL_CONTRACTID_PREFIX "jar"));
  AppProtocolHandler* ph = new AppProtocolHandler();
  if (ph == nullptr) {
    return NS_ERROR_OUT_OF_MEMORY;
  }
  NS_ADDREF(ph);
  nsresult rv = ph->QueryInterface(aIID, aResult);
  NS_RELEASE(ph);
  return rv;
}

NS_IMETHODIMP
AppProtocolHandler::GetScheme(nsACString &aResult)
{
  aResult.AssignLiteral("app");
  return NS_OK;
}

NS_IMETHODIMP
AppProtocolHandler::GetDefaultPort(int32_t *aResult)
{
  // No ports for the app protocol.
  *aResult = -1;
  return NS_OK;
}

NS_IMETHODIMP
AppProtocolHandler::GetProtocolFlags(uint32_t *aResult)
{
  *aResult = URI_NOAUTH |
             URI_DANGEROUS_TO_LOAD |
             URI_CROSS_ORIGIN_NEEDS_WEBAPPS_PERM;
  return NS_OK;
}

NS_IMETHODIMP
AppProtocolHandler::NewURI(const nsACString &aSpec,
                           const char *aCharset, // ignore charset info
                           nsIURI *aBaseURI,
                           nsIURI **result)
{
  nsresult rv;
  nsCOMPtr<nsIStandardURL> surl(do_CreateInstance(NS_STANDARDURL_CONTRACTID, &rv));
  NS_ENSURE_SUCCESS(rv, rv);

  rv = surl->Init(nsIStandardURL::URLTYPE_STANDARD, -1, aSpec, aCharset, aBaseURI);
  NS_ENSURE_SUCCESS(rv, rv);

  nsCOMPtr<nsIURL> url(do_QueryInterface(surl, &rv));
  NS_ENSURE_SUCCESS(rv, rv);

  url.forget(result);
  return NS_OK;
}

NS_IMETHODIMP
AppProtocolHandler::NewChannel2(nsIURI* aUri,
                                nsILoadInfo* aLoadInfo,
                                nsIChannel** aResult)
{
  NS_ENSURE_ARG_POINTER(aUri);
  RefPtr<nsJARChannel> channel = new nsJARChannel();

  nsAutoCString host;
  nsresult rv = aUri->GetHost(host);
  NS_ENSURE_SUCCESS(rv, rv);

  if (Preferences::GetBool("dom.mozApps.themable")) {
    nsAutoCString origin;
    nsPrincipal::GetOriginForURI(aUri, origin);
    nsAdoptingCString themeOrigin;
    themeOrigin = Preferences::GetCString("b2g.theme.origin");
    if (themeOrigin.Equals(origin)) {
      // We are trying to load a theme resource. Check whether we have a
      // package registered as a theme provider to override the file path.
      nsAdoptingCString selectedTheme;
      selectedTheme = Preferences::GetCString("dom.mozApps.selected_theme");
      if (!selectedTheme.IsEmpty()) {
        // Substitute the path with the actual theme.
        host = selectedTheme;
      }
    }
  }

  nsAutoCString fileSpec;
  nsCOMPtr<nsIURL> url = do_QueryInterface(aUri);
  rv = url->GetFilePath(fileSpec);
  NS_ENSURE_SUCCESS(rv, rv);

  mozilla::dom::AppInfo *appInfo;

  if (!mAppInfoCache.Get(host, &appInfo)) {
    nsCOMPtr<nsIAppsService> appsService = do_GetService(APPS_SERVICE_CONTRACTID);
    if (!appsService) {
      return NS_ERROR_FAILURE;
    }

    mozilla::AutoSafeJSContext cx;
    JS::RootedValue jsInfo(cx);
    rv = appsService->GetAppInfo(NS_ConvertUTF8toUTF16(host), &jsInfo);
    if (NS_FAILED(rv) || !jsInfo.isObject()) {
      // Return a DummyChannel.
      printf_stderr("!! Creating a dummy channel for %s (no appInfo)\n", host.get());
      RefPtr<nsIChannel> dummyChannel = new DummyChannel();
      dummyChannel->SetLoadInfo(aLoadInfo);
      dummyChannel.forget(aResult);
      return NS_OK;
    }

    appInfo = new mozilla::dom::AppInfo();
    JSAutoCompartment ac(cx, &jsInfo.toObject());
    if (!appInfo->Init(cx, jsInfo) || appInfo->mPath.IsEmpty()) {
      // Return a DummyChannel.
      printf_stderr("!! Creating a dummy channel for %s (invalid appInfo)\n", host.get());
      RefPtr<nsIChannel> dummyChannel = new DummyChannel();
      dummyChannel->SetLoadInfo(aLoadInfo);
      dummyChannel.forget(aResult);
      return NS_OK;
    }
    mAppInfoCache.Put(host, appInfo);
  }

  // Even core apps are on /system partition and can be accessed directly, but
  // to ease sandboxing code not to handle the special case of core apps, only
  // use scheme jar:file in parent, see bug 1119692 comment 20.
  nsAutoCString jarSpec(XRE_IsParentProcess() ? "jar:file://"
                                              : "jar:remoteopenfile://");
  jarSpec += NS_ConvertUTF16toUTF8(appInfo->mPath) +
             NS_LITERAL_CSTRING("/application.zip!") +
             fileSpec;

  nsCOMPtr<nsIURI> jarURI;
  rv = NS_NewURI(getter_AddRefs(jarURI),
                 jarSpec, nullptr, nullptr);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = channel->Init(jarURI);
  NS_ENSURE_SUCCESS(rv, rv);

  // set the loadInfo on the new channel
  rv = channel->SetLoadInfo(aLoadInfo);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = channel->SetAppURI(aUri);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = channel->SetOriginalURI(aUri);
  NS_ENSURE_SUCCESS(rv, rv);

  channel.forget(aResult);
  return NS_OK;
}

// We map app://ABCDEF/path/to/file.ext to
// jar:file:///path/to/profile/webapps/ABCDEF/application.zip!/path/to/file.ext
NS_IMETHODIMP
AppProtocolHandler::NewChannel(nsIURI* aUri, nsIChannel* *aResult)
{
  return NewChannel2(aUri, nullptr, aResult);
}

NS_IMETHODIMP
AppProtocolHandler::AllowPort(int32_t aPort, const char *aScheme, bool *aRetval)
{
  // No port allowed for this scheme.
  *aRetval = false;
  return NS_OK;
}