/* 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 "SiteIntegrityService.h"

#include "mozilla/Logging.h"
#include "nsComponentManagerUtils.h"
#include "nsIDataStorage.h"
#include "PublicKeyPinningService.h"
#include "nsIURI.h"
#include "nsNetUtil.h"
#include "prtime.h"

using namespace mozilla;

static LazyLogModule gSiteIntegrityLog("SiteIntegrity");

NS_IMPL_ISUPPORTS(SiteIntegrityService, nsISiteIntegrityService)

SiteIntegrityService::~SiteIntegrityService() = default;

nsresult SiteIntegrityService::Init() {
  MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Debug,
              "Initializing SiteIntegrityService");

  nsCOMPtr<nsIDataStorageManager> dataStorageManager(
      do_GetService("@mozilla.org/security/datastoragemanager;1"));
  if (!dataStorageManager) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Warning,
                "Failed to get DataStorageManager");
    return NS_ERROR_FAILURE;
  }

  MOZ_TRY(
      dataStorageManager->Get(nsIDataStorageManager::SiteIntegrityServiceState,
                              getter_AddRefs(mDataStorage)));

  if (!mDataStorage) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Warning,
                "Failed to get DataStorage");
    return NS_ERROR_FAILURE;
  }

  MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Debug,
              "SiteIntegrityService initialized successfully");
  return NS_OK;
}

NS_IMETHODIMP
SiteIntegrityService::SetProtected(nsIURI* aSourceURI,
                                   const OriginAttributes& aOriginAttributes,
                                   uint64_t aMaxAge) {
  MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Debug, "SetProtected: max-age={}",
              aMaxAge);

  nsAutoCString storageKey;
  nsIDataStorage::DataType storageType;
  nsresult rv = GetStorageKeyFromURI(aSourceURI, aOriginAttributes, storageKey,
                                     &storageType);
  if (NS_FAILED(rv)) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Warning,
                "Failed to get storage key: {:x}", static_cast<uint32_t>(rv));
    return rv;
  }

  PRTime now = PR_Now();
  PRTime expirationTime =
      now + (static_cast<PRTime>(aMaxAge) * PR_USEC_PER_SEC);

  nsAutoCString expirationString;
  expirationString.AppendInt(expirationTime);

  mDataStorage->Put(storageKey, expirationString, storageType);

  MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Debug,
              "URI protected successfully, expires at: {}", expirationTime);
  return NS_OK;
}

static nsresult GetHost(nsIURI* aURI, nsACString& outResult) {
  nsCOMPtr<nsIURI> innerURI = NS_GetInnermostURI(aURI);
  if (!innerURI) {
    return NS_ERROR_FAILURE;
  }

  nsAutoCString host;
  nsresult rv = innerURI->GetAsciiHost(host);
  if (NS_FAILED(rv)) {
    return rv;
  }

  outResult.Assign(
      mozilla::psm::PublicKeyPinningService::CanonicalizeHostname(host.get()));
  if (outResult.IsEmpty()) {
    return NS_ERROR_UNEXPECTED;
  }

  return NS_OK;
}

static void GetStorageKey(const nsACString& aHostname,
                          const OriginAttributes& aOriginAttributes,
                          nsAutoCString& outStorageKey) {
  outStorageKey = aHostname;

  // Don't isolate by userContextId.
  OriginAttributes originAttributesNoUserContext = aOriginAttributes;
  originAttributesNoUserContext.mUserContextId =
      nsIScriptSecurityManager::DEFAULT_USER_CONTEXT_ID;

  nsAutoCString originAttributesSuffix;
  originAttributesNoUserContext.CreateSuffix(originAttributesSuffix);

  outStorageKey.Append(originAttributesSuffix);
}

nsresult SiteIntegrityService::GetStorageKeyFromURI(
    nsIURI* aURI, const OriginAttributes& aOriginAttributes,
    nsACString& outStorageKey, nsIDataStorage::DataType* outStorageType) {
  nsAutoCString host;
  nsresult rv = GetHost(aURI, host);
  if (NS_FAILED(rv)) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Warning,
                "Failed to get host from URI: {:x}", static_cast<uint32_t>(rv));
    return rv;
  }

  nsAutoCString storageKey;
  GetStorageKey(host, aOriginAttributes, storageKey);
  outStorageKey.Assign(storageKey);

  *outStorageType = aOriginAttributes.IsPrivateBrowsing()
                        ? nsIDataStorage::DataType::Private
                        : nsIDataStorage::DataType::Persistent;

  MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Verbose,
              "Generated storage key: {} for host: {}", storageKey, host);

  return NS_OK;
}

NS_IMETHODIMP
SiteIntegrityService::IsProtectedURI(nsIURI* aURI,
                                     const OriginAttributes& aOriginAttributes,
                                     bool* outMatch) {
  NS_ENSURE_ARG_POINTER(aURI);
  NS_ENSURE_ARG_POINTER(outMatch);

  *outMatch = false;

  nsAutoCString storageKey;
  nsIDataStorage::DataType storageType;
  nsresult rv =
      GetStorageKeyFromURI(aURI, aOriginAttributes, storageKey, &storageType);
  if (NS_FAILED(rv)) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Warning,
                "IsProtectedURI: Failed to get storage key: {:x}",
                static_cast<uint32_t>(rv));
    return rv;
  }

  MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Verbose,
              "IsProtectedURI: Checking storage key: {}", storageKey);

  nsAutoCString value;
  rv = mDataStorage->Get(storageKey, storageType, value);
  if (rv == NS_ERROR_NOT_AVAILABLE) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Debug,
                "IsProtectedURI: No data found for key");
    return NS_OK;
  }
  if (NS_FAILED(rv)) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Warning,
                "IsProtectedURI: Failed to get data: {:x}",
                static_cast<uint32_t>(rv));
    return rv;
  }

  if (value.IsEmpty()) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Debug,
                "IsProtectedURI: Empty value found");
    return NS_OK;
  }

  nsresult conversionResult;
  PRTime storedExpirationTime = value.ToInteger64(&conversionResult);
  if (NS_FAILED(conversionResult)) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Warning,
                "IsProtectedURI: Failed to parse expiration time");
    return NS_OK;
  }

  PRTime now = PR_Now();
  if (now >= storedExpirationTime) {
    MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Debug,
                "IsProtectedURI: Entry has expired (now: {}, expiration: {})",
                now, storedExpirationTime);
    mDataStorage->Remove(storageKey, storageType);
    return NS_OK;
  }

  MOZ_LOG_FMT(gSiteIntegrityLog, LogLevel::Debug,
              "IsProtectedURI: Entry is valid (now: {}, expiration: {})", now,
              storedExpirationTime);
  *outMatch = true;
  return NS_OK;
}