/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 "mozilla/ResultExtensions.h"
#include "nsAutoConfig.h"
#include "nsJSConfigTriggers.h"

#include "nsIURI.h"
#include "nsIHttpChannel.h"
#include "nsThreadUtils.h"
#include "nsAppDirectoryServiceDefs.h"
#include "nsIObserverService.h"
#include "nsLiteralString.h"
#include "nsIPromptService.h"
#include "nsIInputStream.h"
#include "nsIOutputStream.h"
#include "nsIPrefBranch.h"
#include "nsIPrefService.h"
#include "nsIStringBundle.h"
#include "nsContentUtils.h"
#include "nsCRT.h"
#include "nsNetCID.h"
#include "nsNetUtil.h"
#include "nspr.h"
#include <algorithm>

#include "mozilla/IntegerPrintfMacros.h"
#include "mozilla/Logging.h"
#include "mozilla/SpinEventLoopUntil.h"

using mozilla::LogLevel;

mozilla::LazyLogModule MCD("MCD");

// nsISupports Implementation

NS_IMPL_ISUPPORTS(nsAutoConfig, nsITimerCallback, nsIStreamListener,
                  nsIObserver, nsIRequestObserver, nsISupportsWeakReference,
                  nsINamed)

nsAutoConfig::nsAutoConfig() {}

nsresult nsAutoConfig::Init() {
  // member initializers and constructor code

  nsresult rv;
  mLoaded = false;

  // Registering the object as an observer to the profile-after-change topic
  nsCOMPtr<nsIObserverService> observerService =
      do_GetService("@mozilla.org/observer-service;1", &rv);
  if (NS_FAILED(rv)) return rv;

  rv = observerService->AddObserver(this, "profile-after-change", true);

  return rv;
}

nsAutoConfig::~nsAutoConfig() {}

void nsAutoConfig::SetConfigURL(const char* aConfigURL) {
  mConfigURL.Assign(aConfigURL);
}

NS_IMETHODIMP
nsAutoConfig::OnStartRequest(nsIRequest* request) { return NS_OK; }

NS_IMETHODIMP
nsAutoConfig::OnDataAvailable(nsIRequest* request, nsIInputStream* aIStream,
                              uint64_t aSourceOffset, uint32_t aLength) {
  uint32_t amt, size;
  nsresult rv;
  char buf[1024];

  while (aLength) {
    size = std::min<size_t>(aLength, sizeof(buf));
    rv = aIStream->Read(buf, size, &amt);
    if (NS_FAILED(rv)) return rv;
    mBuf.Append(buf, amt);
    aLength -= amt;
  }
  return NS_OK;
}

NS_IMETHODIMP
nsAutoConfig::OnStopRequest(nsIRequest* request, nsresult aStatus) {
  nsresult rv;

  // If the request is failed, go read the failover.jsc file
  if (NS_FAILED(aStatus)) {
    MOZ_LOG(MCD, LogLevel::Debug,
            ("mcd request failed with status %" PRIx32 "\n",
             static_cast<uint32_t>(aStatus)));
    return readOfflineFile();
  }

  // Checking for the http response, if failure go read the failover file.
  nsCOMPtr<nsIHttpChannel> pHTTPCon(do_QueryInterface(request));
  if (pHTTPCon) {
    uint32_t httpStatus;
    rv = pHTTPCon->GetResponseStatus(&httpStatus);
    if (NS_FAILED(rv) || httpStatus != 200) {
      MOZ_LOG(MCD, LogLevel::Debug,
              ("mcd http request failed with status %x\n", httpStatus));
      return readOfflineFile();
    }
  }

  // Send the autoconfig.jsc to javascript engine.

  rv = EvaluateAdminConfigScript(mBuf.get(), mBuf.Length(), nullptr, false,
                                 true, false);
  if (NS_SUCCEEDED(rv)) {
    // Write the autoconfig.jsc to failover.jsc (cached copy)
    rv = writeFailoverFile();

    if (NS_FAILED(rv)) NS_WARNING("Error writing failover.jsc file");

    // Releasing the lock to allow the main thread to start execution
    mLoaded = true;

    return NS_OK;
  }
  // there is an error in parsing of the autoconfig file.
  NS_WARNING(
      "Error reading autoconfig.jsc from the network, reading the offline "
      "version");
  return readOfflineFile();
}

// Notify method as a TimerCallBack function
NS_IMETHODIMP nsAutoConfig::Notify(nsITimer* timer) {
  downloadAutoConfig();
  return NS_OK;
}

NS_IMETHODIMP
nsAutoConfig::GetName(nsACString& aName) {
  aName.AssignLiteral("nsAutoConfig");
  return NS_OK;
}

/* Observe() is called twice: once at the instantiation time and other
   after the profile is set. It doesn't do anything but return NS_OK during the
   creation time. Second time it calls  downloadAutoConfig().
*/

NS_IMETHODIMP nsAutoConfig::Observe(nsISupports* aSubject, const char* aTopic,
                                    const char16_t* someData) {
  nsresult rv = NS_OK;
  if (!nsCRT::strcmp(aTopic, "profile-after-change")) {
    // We will be calling downloadAutoConfig even if there is no profile
    // name. Nothing will be passed as a parameter to the URL and the
    // default case will be picked up by the script.

    rv = downloadAutoConfig();
  }

  return rv;
}

nsresult nsAutoConfig::downloadAutoConfig() {
  nsresult rv;
  nsAutoCString emailAddr;
  static bool firstTime = true;

  if (mConfigURL.IsEmpty()) {
    MOZ_LOG(MCD, LogLevel::Debug,
            ("global config url is empty - did you set "
             "autoadmin.global_config_url?\n"));
    NS_WARNING("AutoConfig called without global_config_url");
    return NS_OK;
  }

  // If there is an email address appended as an argument to the ConfigURL
  // in the previous read, we need to remove it when timer kicks in and
  // downloads the autoconfig file again.
  // If necessary, the email address will be added again as an argument.
  int32_t index = mConfigURL.RFindChar((char16_t)'?');
  if (index != -1) mConfigURL.Truncate(index);

  // Clean up the previous read, the new read is going to use the same buffer
  if (!mBuf.IsEmpty()) mBuf.Truncate(0);

  // Get the preferences branch and save it to the member variable
  if (!mPrefBranch) {
    nsCOMPtr<nsIPrefService> prefs =
        do_GetService(NS_PREFSERVICE_CONTRACTID, &rv);
    if (NS_FAILED(rv)) return rv;

    rv = prefs->GetBranch(nullptr, getter_AddRefs(mPrefBranch));
    if (NS_FAILED(rv)) return rv;
  }

  // Check to see if the network is online/offline
  nsCOMPtr<nsIIOService> ios = do_GetService(NS_IOSERVICE_CONTRACTID, &rv);
  if (NS_FAILED(rv)) return rv;

  bool offline;
  rv = ios->GetOffline(&offline);
  if (NS_FAILED(rv)) return rv;

  if (offline) {
    bool offlineFailover;
    rv = mPrefBranch->GetBoolPref("autoadmin.offline_failover",
                                  &offlineFailover);
    // Read the failover.jsc if the network is offline and the pref says so
    if (NS_SUCCEEDED(rv) && offlineFailover) return readOfflineFile();
  }

  /* Append user's identity at the end of the URL if the pref says so.
     First we are checking for the user's email address but if it is not
     available in the case where the client is used without messenger, user's
     profile name will be used as an unique identifier
  */
  bool appendMail;
  rv = mPrefBranch->GetBoolPref("autoadmin.append_emailaddr", &appendMail);
  if (NS_SUCCEEDED(rv) && appendMail) {
    rv = getEmailAddr(emailAddr);
    if (NS_SUCCEEDED(rv) && emailAddr.get()) {
      /* Adding the unique identifier at the end of autoconfig URL.
         In this case the autoconfig URL is a script and
         emailAddr as passed as an argument
      */
      mConfigURL.Append('?');
      mConfigURL.Append(emailAddr);
    }
  }

  // create a new url
  nsCOMPtr<nsIURI> url;
  nsCOMPtr<nsIChannel> channel;

  rv = NS_NewURI(getter_AddRefs(url), mConfigURL);
  if (NS_FAILED(rv)) {
    MOZ_LOG(
        MCD, LogLevel::Debug,
        ("failed to create URL - is autoadmin.global_config_url valid? - %s\n",
         mConfigURL.get()));
    return rv;
  }

  MOZ_LOG(MCD, LogLevel::Debug, ("running MCD url %s\n", mConfigURL.get()));
  // open a channel for the url
  rv = NS_NewChannel(
      getter_AddRefs(channel), url, nsContentUtils::GetSystemPrincipal(),
      nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
      nsIContentPolicy::TYPE_OTHER,
      nullptr,  // nsICookieJarSettings
      nullptr,  // PerformanceStorage
      nullptr,  // loadGroup
      nullptr,  // aCallbacks
      nsIRequest::INHIBIT_PERSISTENT_CACHING | nsIRequest::LOAD_BYPASS_CACHE);

  if (NS_FAILED(rv)) return rv;

  rv = channel->AsyncOpen(this);
  if (NS_FAILED(rv)) {
    readOfflineFile();
    return rv;
  }

  // Set a repeating timer if the pref is set.
  // This is to be done only once.
  // Also We are having the event queue processing only for the startup
  // It is not needed with the repeating timer.
  if (firstTime) {
    firstTime = false;

    /* process events until we're finished. AutoConfig.jsc reading needs
       to be finished before the browser starts loading up
       We are waiting for the mLoaded which will be set through
       onStopRequest or readOfflineFile methods
       There is a possibility of deadlock so we need to make sure
       that mLoaded will be set to true in any case (success/failure)
    */

    if (!mozilla::SpinEventLoopUntil([&]() { return mLoaded; })) {
      return NS_ERROR_FAILURE;
    }

    int32_t minutes;
    rv = mPrefBranch->GetIntPref("autoadmin.refresh_interval", &minutes);
    if (NS_SUCCEEDED(rv) && minutes > 0) {
      // Create a new timer and pass this nsAutoConfig
      // object as a timer callback.
      MOZ_TRY_VAR(mTimer,
                  NS_NewTimerWithCallback(this, minutes * 60 * 1000,
                                          nsITimer::TYPE_REPEATING_SLACK));
    }
  }  // first_time

  return NS_OK;
}  // nsPref::downloadAutoConfig()

nsresult nsAutoConfig::readOfflineFile() {
  nsresult rv;

  /* Releasing the lock to allow main thread to start
     execution. At this point we do not need to stall
     the thread since all network activities are done.
  */
  mLoaded = true;

  bool failCache;
  rv = mPrefBranch->GetBoolPref("autoadmin.failover_to_cached", &failCache);
  if (NS_SUCCEEDED(rv) && !failCache) {
    // disable network connections and return.

    nsCOMPtr<nsIIOService> ios = do_GetService(NS_IOSERVICE_CONTRACTID, &rv);
    if (NS_FAILED(rv)) return rv;

    bool offline;
    rv = ios->GetOffline(&offline);
    if (NS_FAILED(rv)) return rv;

    if (!offline) {
      rv = ios->SetOffline(true);
      if (NS_FAILED(rv)) return rv;
    }

    // lock the "network.online" prference so user cannot toggle back to
    // online mode.
    rv = mPrefBranch->SetBoolPref("network.online", false);
    if (NS_FAILED(rv)) return rv;

    mPrefBranch->LockPref("network.online");
    return NS_OK;
  }

  /* faiover_to_cached is set to true so
     Open the file and read the content.
     execute the javascript file
  */

  nsCOMPtr<nsIFile> failoverFile;
  rv = NS_GetSpecialDirectory(NS_APP_USER_PROFILE_50_DIR,
                              getter_AddRefs(failoverFile));
  if (NS_FAILED(rv)) return rv;

  failoverFile->AppendNative("failover.jsc"_ns);
  rv = evaluateLocalFile(failoverFile);
  if (NS_FAILED(rv))
    NS_WARNING("Couldn't open failover.jsc, going back to default prefs");
  return NS_OK;
}

nsresult nsAutoConfig::evaluateLocalFile(nsIFile* file) {
  nsresult rv;
  nsCOMPtr<nsIInputStream> inStr;

  rv = NS_NewLocalFileInputStream(getter_AddRefs(inStr), file);
  if (NS_FAILED(rv)) return rv;

  int64_t fileSize;
  file->GetFileSize(&fileSize);
  uint32_t fs = fileSize;  // Converting 64 bit structure to unsigned int
  char* buf = (char*)malloc(fs * sizeof(char));
  if (!buf) return NS_ERROR_OUT_OF_MEMORY;

  uint32_t amt = 0;
  rv = inStr->Read(buf, fs, &amt);
  if (NS_SUCCEEDED(rv)) {
    EvaluateAdminConfigScript(buf, fs, nullptr, false, true, false);
  }
  inStr->Close();
  free(buf);
  return rv;
}

nsresult nsAutoConfig::writeFailoverFile() {
  nsresult rv;
  nsCOMPtr<nsIFile> failoverFile;
  nsCOMPtr<nsIOutputStream> outStr;
  uint32_t amt;

  rv = NS_GetSpecialDirectory(NS_APP_USER_PROFILE_50_DIR,
                              getter_AddRefs(failoverFile));
  if (NS_FAILED(rv)) return rv;

  failoverFile->AppendNative("failover.jsc"_ns);

  rv = NS_NewLocalFileOutputStream(getter_AddRefs(outStr), failoverFile);
  if (NS_FAILED(rv)) return rv;
  rv = outStr->Write(mBuf.get(), mBuf.Length(), &amt);
  outStr->Close();
  return rv;
}

nsresult nsAutoConfig::getEmailAddr(nsACString& emailAddr) {
  nsresult rv;
  nsAutoCString prefValue;

  /* Getting an email address through set of three preferences:
     First getting a default account with
     "mail.accountmanager.defaultaccount"
     second getting an associated id with the default account
     Third getting an email address with id
  */

  rv =
      mPrefBranch->GetCharPref("mail.accountmanager.defaultaccount", prefValue);
  if (NS_SUCCEEDED(rv) && !prefValue.IsEmpty()) {
    emailAddr = "mail.account."_ns + prefValue + ".identities"_ns;
    rv = mPrefBranch->GetCharPref(PromiseFlatCString(emailAddr).get(),
                                  prefValue);
    if (NS_FAILED(rv) || prefValue.IsEmpty())
      return PromptForEMailAddress(emailAddr);
    int32_t commandIndex = prefValue.FindChar(',');
    if (commandIndex != kNotFound) prefValue.Truncate(commandIndex);
    emailAddr = "mail.identity."_ns + prefValue + ".useremail"_ns;
    rv = mPrefBranch->GetCharPref(PromiseFlatCString(emailAddr).get(),
                                  prefValue);
    if (NS_FAILED(rv) || prefValue.IsEmpty())
      return PromptForEMailAddress(emailAddr);
    emailAddr = prefValue;
  } else {
    // look for 4.x pref in case we just migrated.
    rv = mPrefBranch->GetCharPref("mail.identity.useremail", prefValue);
    if (NS_SUCCEEDED(rv) && !prefValue.IsEmpty())
      emailAddr = prefValue;
    else
      PromptForEMailAddress(emailAddr);
  }

  return NS_OK;
}

nsresult nsAutoConfig::PromptForEMailAddress(nsACString& emailAddress) {
  nsresult rv;
  nsCOMPtr<nsIPromptService> promptService =
      do_GetService("@mozilla.org/embedcomp/prompt-service;1", &rv);
  NS_ENSURE_SUCCESS(rv, rv);
  nsCOMPtr<nsIStringBundleService> bundleService =
      do_GetService(NS_STRINGBUNDLE_CONTRACTID, &rv);
  NS_ENSURE_SUCCESS(rv, rv);

  nsCOMPtr<nsIStringBundle> bundle;
  rv = bundleService->CreateBundle(
      "chrome://autoconfig/locale/autoconfig.properties",
      getter_AddRefs(bundle));
  NS_ENSURE_SUCCESS(rv, rv);

  nsAutoString title;
  rv = bundle->GetStringFromName("emailPromptTitle", title);
  NS_ENSURE_SUCCESS(rv, rv);

  nsAutoString err;
  rv = bundle->GetStringFromName("emailPromptMsg", err);
  NS_ENSURE_SUCCESS(rv, rv);
  bool check = false;
  nsString emailResult;
  bool success;
  rv = promptService->Prompt(nullptr, title.get(), err.get(),
                             getter_Copies(emailResult), nullptr, &check,
                             &success);
  if (!success) return NS_ERROR_FAILURE;
  NS_ENSURE_SUCCESS(rv, rv);
  LossyCopyUTF16toASCII(emailResult, emailAddress);
  return NS_OK;
}