/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et: */
/* 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 "nsMIMEInfoImpl.h"
#include "nsString.h"
#include "nsReadableUtils.h"
#include "nsStringEnumerator.h"
#include "nsIFile.h"
#include "nsIFileURL.h"
#include "nsEscape.h"
#include "nsCURILoader.h"
#include "nsCExternalHandlerService.h"
#include "nsIExternalProtocolService.h"
#include "nsIObserverService.h"
#include "mozilla/StaticPtr.h"
#include "xpcpublic.h"

static bool sInitializedOurData = false;
StaticRefPtr<nsIFile> sOurAppFile;

/* static */
already_AddRefed<nsIFile> nsMIMEInfoBase::GetCanonicalExecutable(
    nsIFile* aFile) {
  nsCOMPtr<nsIFile> binary = aFile;
#ifdef XP_MACOSX
  nsAutoString path;
  if (binary) {
    binary->GetPath(path);
  }
  if (!StringEndsWith(path, u".app"_ns) && path.RFind(u".app/"_ns) == -1) {
    // This shouldn't ever happen with Firefox's own binary, tracked in
    // sOurAppFile, but might happen when called with other files.
    return binary.forget();
  }
  nsAutoString leafName;
  if (binary) {
    binary->GetLeafName(leafName);
  }
  while (binary && !StringEndsWith(leafName, u".app"_ns)) {
    nsCOMPtr<nsIFile> parent;
    binary->GetParent(getter_AddRefs(parent));
    binary = std::move(parent);
    if (binary) {
      binary->GetLeafName(leafName);
    }
  }
#endif
  return binary.forget();
}

static void EnsureAppDetailsAvailable() {
  if (sInitializedOurData) {
    return;
  }
  sInitializedOurData = true;
  nsCOMPtr<nsIFile> binary;
  XRE_GetBinaryPath(getter_AddRefs(binary));
  sOurAppFile = nsMIMEInfoBase::GetCanonicalExecutable(binary);
  ClearOnShutdown(&sOurAppFile);
}

// nsISupports methods
NS_IMPL_ADDREF(nsMIMEInfoBase)
NS_IMPL_RELEASE(nsMIMEInfoBase)

NS_INTERFACE_MAP_BEGIN(nsMIMEInfoBase)
  NS_INTERFACE_MAP_ENTRY(nsIHandlerInfo)
  // This is only an nsIMIMEInfo if it's a MIME handler.
  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(nsIMIMEInfo, mClass == eMIMEInfo)
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIHandlerInfo)
NS_INTERFACE_MAP_END

// nsMIMEInfoImpl methods

// Constructors for a MIME handler.
nsMIMEInfoBase::nsMIMEInfoBase(const char* aMIMEType)
    : mSchemeOrType(aMIMEType),
      mClass(eMIMEInfo),
      mPreferredAction(nsIMIMEInfo::saveToDisk),
      mAlwaysAskBeforeHandling(
          StaticPrefs::
              browser_download_always_ask_before_handling_new_types()) {}

nsMIMEInfoBase::nsMIMEInfoBase(const nsACString& aMIMEType)
    : mSchemeOrType(aMIMEType),
      mClass(eMIMEInfo),
      mPreferredAction(nsIMIMEInfo::saveToDisk),
      mAlwaysAskBeforeHandling(
          StaticPrefs::
              browser_download_always_ask_before_handling_new_types()) {}

// Constructor for a handler that lets the caller specify whether this is a
// MIME handler or a protocol handler.  In the long run, these will be distinct
// classes (f.e. nsMIMEInfo and nsProtocolInfo), but for now we reuse this class
// for both and distinguish between the two kinds of handlers via the aClass
// argument to this method, which can be either eMIMEInfo or eProtocolInfo.
nsMIMEInfoBase::nsMIMEInfoBase(const nsACString& aType, HandlerClass aClass)
    : mSchemeOrType(aType),
      mClass(aClass),
      mPreferredAction(nsIMIMEInfo::saveToDisk),
      mAlwaysAskBeforeHandling(
          StaticPrefs::
              browser_download_always_ask_before_handling_new_types() ||
          aClass != eMIMEInfo) {}

nsMIMEInfoBase::~nsMIMEInfoBase() {}

NS_IMETHODIMP
nsMIMEInfoBase::GetFileExtensions(nsIUTF8StringEnumerator** aResult) {
  return NS_NewUTF8StringEnumerator(aResult, &mExtensions, this);
}

NS_IMETHODIMP
nsMIMEInfoBase::ExtensionExists(const nsACString& aExtension, bool* _retval) {
  MOZ_ASSERT(!aExtension.IsEmpty(), "no extension");
  *_retval = mExtensions.Contains(aExtension,
                                  nsCaseInsensitiveCStringArrayComparator());
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::GetPrimaryExtension(nsACString& _retval) {
  if (!mExtensions.Length()) {
    _retval.Truncate();
    return NS_ERROR_NOT_INITIALIZED;
  }
  _retval = mExtensions[0];
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::SetPrimaryExtension(const nsACString& aExtension) {
  if (MOZ_UNLIKELY(aExtension.IsEmpty())) {
    MOZ_ASSERT(false, "No extension");
    return NS_ERROR_INVALID_ARG;
  }
  int32_t i = mExtensions.IndexOf(aExtension, 0,
                                  nsCaseInsensitiveCStringArrayComparator());
  if (i != -1) {
    mExtensions.RemoveElementAt(i);
  }
  mExtensions.InsertElementAt(0, aExtension);
  return NS_OK;
}

void nsMIMEInfoBase::AddUniqueExtension(const nsACString& aExtension) {
  if (!aExtension.IsEmpty() &&
      !mExtensions.Contains(aExtension,
                            nsCaseInsensitiveCStringArrayComparator())) {
    mExtensions.AppendElement(aExtension);
  }
}

NS_IMETHODIMP
nsMIMEInfoBase::AppendExtension(const nsACString& aExtension) {
  MOZ_ASSERT(!aExtension.IsEmpty(), "No extension");
  AddUniqueExtension(aExtension);
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::GetType(nsACString& aType) {
  if (mSchemeOrType.IsEmpty()) return NS_ERROR_NOT_INITIALIZED;

  aType = mSchemeOrType;
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::GetMIMEType(nsACString& aMIMEType) {
  if (mSchemeOrType.IsEmpty()) return NS_ERROR_NOT_INITIALIZED;

  aMIMEType = mSchemeOrType;
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::GetDescription(nsAString& aDescription) {
  aDescription = mDescription;
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::SetDescription(const nsAString& aDescription) {
  mDescription = aDescription;
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::Equals(nsIMIMEInfo* aMIMEInfo, bool* _retval) {
  if (!aMIMEInfo) return NS_ERROR_NULL_POINTER;

  nsAutoCString type;
  nsresult rv = aMIMEInfo->GetMIMEType(type);
  if (NS_FAILED(rv)) return rv;

  *_retval = mSchemeOrType.Equals(type);

  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::SetFileExtensions(const nsACString& aExtensions) {
  mExtensions.Clear();
  nsACString::const_iterator start, end;
  aExtensions.BeginReading(start);
  aExtensions.EndReading(end);
  while (start != end) {
    nsACString::const_iterator cursor = start;
    mozilla::Unused << FindCharInReadable(',', cursor, end);
    AddUniqueExtension(Substring(start, cursor));
    // If a comma was found, skip it for the next search.
    start = cursor != end ? ++cursor : cursor;
  }
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::GetDefaultDescription(nsAString& aDefaultDescription) {
  aDefaultDescription = mDefaultAppDescription;
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::GetPreferredApplicationHandler(
    nsIHandlerApp** aPreferredAppHandler) {
  *aPreferredAppHandler = mPreferredApplication;
  NS_IF_ADDREF(*aPreferredAppHandler);
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::SetPreferredApplicationHandler(
    nsIHandlerApp* aPreferredAppHandler) {
  mPreferredApplication = aPreferredAppHandler;
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::GetPossibleApplicationHandlers(
    nsIMutableArray** aPossibleAppHandlers) {
  if (!mPossibleApplications)
    mPossibleApplications = do_CreateInstance(NS_ARRAY_CONTRACTID);

  if (!mPossibleApplications) return NS_ERROR_OUT_OF_MEMORY;

  *aPossibleAppHandlers = mPossibleApplications;
  NS_IF_ADDREF(*aPossibleAppHandlers);
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::GetPreferredAction(nsHandlerInfoAction* aPreferredAction) {
  *aPreferredAction = mPreferredAction;
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::SetPreferredAction(nsHandlerInfoAction aPreferredAction) {
  mPreferredAction = aPreferredAction;
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::GetAlwaysAskBeforeHandling(bool* aAlwaysAsk) {
  *aAlwaysAsk = mAlwaysAskBeforeHandling;

  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::SetAlwaysAskBeforeHandling(bool aAlwaysAsk) {
  mAlwaysAskBeforeHandling = aAlwaysAsk;
  return NS_OK;
}

/* static */
nsresult nsMIMEInfoBase::GetLocalFileFromURI(nsIURI* aURI, nsIFile** aFile) {
  nsresult rv;

  nsCOMPtr<nsIFileURL> fileUrl = do_QueryInterface(aURI, &rv);
  if (NS_FAILED(rv)) {
    return rv;
  }

  nsCOMPtr<nsIFile> file;
  rv = fileUrl->GetFile(getter_AddRefs(file));
  if (NS_FAILED(rv)) {
    return rv;
  }

  file.forget(aFile);
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoBase::LaunchWithFile(nsIFile* aFile) {
  nsresult rv;

  // it doesn't make any sense to call this on protocol handlers
  NS_ASSERTION(mClass == eMIMEInfo,
               "nsMIMEInfoBase should have mClass == eMIMEInfo");

  if (AutomationOnlyCheckIfLaunchStubbed(aFile)) {
    return NS_OK;
  }

  if (mPreferredAction == useSystemDefault) {
    return LaunchDefaultWithFile(aFile);
  }

  if (mPreferredAction == useHelperApp) {
    if (!mPreferredApplication) return NS_ERROR_FILE_NOT_FOUND;

    // at the moment, we only know how to hand files off to local handlers
    nsCOMPtr<nsILocalHandlerApp> localHandler =
        do_QueryInterface(mPreferredApplication, &rv);
    NS_ENSURE_SUCCESS(rv, rv);

    nsCOMPtr<nsIFile> executable;
    rv = localHandler->GetExecutable(getter_AddRefs(executable));
    NS_ENSURE_SUCCESS(rv, rv);

    return LaunchWithIProcess(executable, aFile->NativePath());
  }

  return NS_ERROR_INVALID_ARG;
}

bool nsMIMEInfoBase::AutomationOnlyCheckIfLaunchStubbed(nsIFile* aFile) {
  // This is pretty gross and hacky, but otherwise we can't automatically
  // test this, and we keep breaking edgecases around this, so...
  if (!xpc::IsInAutomation()) {
    return false;
  }
  nsAutoString path;
  aFile->GetPath(path);
  nsCOMPtr<nsISupportsPRBool> canOpen =
      do_CreateInstance("@mozilla.org/supports-PRBool;1");
  canOpen->SetData(true);
  nsCOMPtr<nsIObserverService> observerService =
      mozilla::services::GetObserverService();
  observerService->NotifyObservers(canOpen, "test-only-opening-downloaded-file",
                                   path.get());
  bool data = true;
  canOpen->GetData(&data);
  return !data;
}

NS_IMETHODIMP
nsMIMEInfoBase::LaunchWithURI(nsIURI* aURI, BrowsingContext* aBrowsingContext) {
  // This is only being called with protocol handlers
  NS_ASSERTION(mClass == eProtocolInfo,
               "nsMIMEInfoBase should be a protocol handler");

  if (mPreferredAction == useSystemDefault) {
    // First, ensure we're not accidentally going to call ourselves.
    // That'd lead to an infinite loop (see bug 215554).
    nsCOMPtr<nsIExternalProtocolService> extProtService =
        do_GetService(NS_EXTERNALPROTOCOLSERVICE_CONTRACTID);
    if (!extProtService) {
      return NS_ERROR_FAILURE;
    }
    nsAutoCString scheme;
    aURI->GetScheme(scheme);
    bool isDefault = false;
    nsresult rv =
        extProtService->IsCurrentAppOSDefaultForProtocol(scheme, &isDefault);
    if (NS_SUCCEEDED(rv) && isDefault) {
      // Lie. This will trip the handler service into showing a dialog asking
      // what the user wants.
      return NS_ERROR_FILE_NOT_FOUND;
    }
    return LoadUriInternal(aURI);
  }

  if (mPreferredAction == useHelperApp) {
    if (!mPreferredApplication) return NS_ERROR_FILE_NOT_FOUND;

    EnsureAppDetailsAvailable();
    nsCOMPtr<nsILocalHandlerApp> localPreferredHandler =
        do_QueryInterface(mPreferredApplication);
    if (localPreferredHandler) {
      nsCOMPtr<nsIFile> executable;
      localPreferredHandler->GetExecutable(getter_AddRefs(executable));
      executable = GetCanonicalExecutable(executable);
      bool isOurExecutable = false;
      if (!executable ||
          NS_FAILED(executable->Equals(sOurAppFile, &isOurExecutable)) ||
          isOurExecutable) {
        // Lie. This will trip the handler service into showing a dialog asking
        // what the user wants.
        return NS_ERROR_FILE_NOT_FOUND;
      }
    }
    return mPreferredApplication->LaunchWithURI(aURI, aBrowsingContext);
  }

  return NS_ERROR_INVALID_ARG;
}

void nsMIMEInfoBase::CopyBasicDataTo(nsMIMEInfoBase* aOther) {
  aOther->mSchemeOrType = mSchemeOrType;
  aOther->mDefaultAppDescription = mDefaultAppDescription;
  aOther->mExtensions = mExtensions.Clone();
}

/* static */
already_AddRefed<nsIProcess> nsMIMEInfoBase::InitProcess(nsIFile* aApp,
                                                         nsresult* aResult) {
  NS_ASSERTION(aApp, "Unexpected null pointer, fix caller");

  nsCOMPtr<nsIProcess> process =
      do_CreateInstance(NS_PROCESS_CONTRACTID, aResult);
  if (NS_FAILED(*aResult)) return nullptr;

  *aResult = process->Init(aApp);
  if (NS_FAILED(*aResult)) return nullptr;

  return process.forget();
}

/* static */
nsresult nsMIMEInfoBase::LaunchWithIProcess(nsIFile* aApp,
                                            const nsCString& aArg) {
  nsresult rv;
  nsCOMPtr<nsIProcess> process = InitProcess(aApp, &rv);
  if (NS_FAILED(rv)) return rv;

  const char* string = aArg.get();

  return process->Run(false, &string, 1);
}

/* static */
nsresult nsMIMEInfoBase::LaunchWithIProcess(nsIFile* aApp,
                                            const nsString& aArg) {
  nsresult rv;
  nsCOMPtr<nsIProcess> process = InitProcess(aApp, &rv);
  if (NS_FAILED(rv)) return rv;

  const char16_t* string = aArg.get();

  return process->Runw(false, &string, 1);
}

/* static */
nsresult nsMIMEInfoBase::LaunchWithIProcess(nsIFile* aApp, const int aArgc,
                                            const char16_t** aArgv) {
  nsresult rv;
  nsCOMPtr<nsIProcess> process = InitProcess(aApp, &rv);
  if (NS_FAILED(rv)) {
    return rv;
  }

  return process->Runw(false, aArgv, aArgc);
}

// nsMIMEInfoImpl implementation
NS_IMETHODIMP
nsMIMEInfoImpl::GetDefaultDescription(nsAString& aDefaultDescription) {
  if (mDefaultAppDescription.IsEmpty() && mDefaultApplication) {
    // Don't want to cache this, just in case someone resets the app
    // without changing the description....
    mDefaultApplication->GetLeafName(aDefaultDescription);
  } else {
    aDefaultDescription = mDefaultAppDescription;
  }

  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoImpl::GetHasDefaultHandler(bool* _retval) {
  *_retval = !mDefaultAppDescription.IsEmpty();
  if (mDefaultApplication) {
    bool exists;
    *_retval = NS_SUCCEEDED(mDefaultApplication->Exists(&exists)) && exists;
  }
  return NS_OK;
}

NS_IMETHODIMP
nsMIMEInfoImpl::IsCurrentAppOSDefault(bool* _retval) {
  *_retval = false;
  if (mDefaultApplication) {
    // Determine if the default executable is our executable.
    EnsureAppDetailsAvailable();
    bool isSame = false;
    nsresult rv = mDefaultApplication->Equals(sOurAppFile, &isSame);
    if (NS_FAILED(rv)) {
      return rv;
    }
    *_retval = isSame;
  }
  return NS_OK;
}

nsresult nsMIMEInfoImpl::LaunchDefaultWithFile(nsIFile* aFile) {
  if (!mDefaultApplication) return NS_ERROR_FILE_NOT_FOUND;

  return LaunchWithIProcess(mDefaultApplication, aFile->NativePath());
}

NS_IMETHODIMP
nsMIMEInfoBase::GetPossibleLocalHandlers(nsIArray** _retval) {
  return NS_ERROR_NOT_IMPLEMENTED;
}