/* -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* 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 "OfflineCacheUpdateGlue.h"
#include "nsOfflineCacheUpdate.h"
#include "mozilla/Services.h"

#include "nsIApplicationCache.h"
#include "nsIApplicationCacheChannel.h"
#include "nsIApplicationCacheContainer.h"
#include "nsIChannel.h"
#include "nsIDocument.h"
#include "mozilla/Logging.h"

//
// To enable logging (see mozilla/Logging.h for full details):
//
//    set MOZ_LOG=nsOfflineCacheUpdate:5
//    set MOZ_LOG_FILE=offlineupdate.log
//
// this enables LogLevel::Info level information and places all output in
// the file offlineupdate.log
//
extern mozilla::LazyLogModule gOfflineCacheUpdateLog;

#undef LOG
#define LOG(args) MOZ_LOG(gOfflineCacheUpdateLog, mozilla::LogLevel::Debug, args)

#undef LOG_ENABLED
#define LOG_ENABLED() MOZ_LOG_TEST(gOfflineCacheUpdateLog, mozilla::LogLevel::Debug)

namespace mozilla {
namespace docshell {

//-----------------------------------------------------------------------------
// OfflineCacheUpdateGlue::nsISupports
//-----------------------------------------------------------------------------

NS_IMPL_ISUPPORTS(OfflineCacheUpdateGlue,
                  nsIOfflineCacheUpdate,
                  nsIOfflineCacheUpdateObserver,
                  nsISupportsWeakReference)

//-----------------------------------------------------------------------------
// OfflineCacheUpdateGlue <public>
//-----------------------------------------------------------------------------

OfflineCacheUpdateGlue::OfflineCacheUpdateGlue()
: mCoalesced(false)
{
    LOG(("OfflineCacheUpdateGlue::OfflineCacheUpdateGlue [%p]", this));
}

OfflineCacheUpdateGlue::~OfflineCacheUpdateGlue()
{
    LOG(("OfflineCacheUpdateGlue::~OfflineCacheUpdateGlue [%p]", this));
}

nsIOfflineCacheUpdate*
OfflineCacheUpdateGlue::EnsureUpdate()
{
    if (!mUpdate) {
        mUpdate = new nsOfflineCacheUpdate();
        LOG(("OfflineCacheUpdateGlue [%p] is using update [%p]", this, mUpdate.get()));
    }

    return mUpdate;
}

NS_IMETHODIMP
OfflineCacheUpdateGlue::Schedule()
{
    nsCOMPtr<nsIObserverService> observerService =
        mozilla::services::GetObserverService();
    if (observerService) {
        LOG(("Calling offline-cache-update-added"));
        observerService->NotifyObservers(static_cast<nsIOfflineCacheUpdate*>(this),
                                         "offline-cache-update-added",
                                         nullptr);
        LOG(("Done offline-cache-update-added"));
    }

    if (!EnsureUpdate())
        return NS_ERROR_NULL_POINTER;

    // Do not use weak reference, we must survive!
    mUpdate->AddObserver(this, false);

    if (mCoalesced) // already scheduled
        return NS_OK;

    return mUpdate->Schedule();
}

NS_IMETHODIMP
OfflineCacheUpdateGlue::Init(nsIURI *aManifestURI,
                             nsIURI *aDocumentURI,
                             nsIPrincipal* aLoadingPrincipal,
                             nsIDOMDocument *aDocument,
                             nsIFile *aCustomProfileDir)
{
    nsresult rv;

    nsAutoCString originSuffix;
    rv = aLoadingPrincipal->GetOriginSuffix(originSuffix);
    NS_ENSURE_SUCCESS(rv, rv);

    nsOfflineCacheUpdateService* service =
        nsOfflineCacheUpdateService::EnsureService();
    if (service) {
        service->FindUpdate(aManifestURI, originSuffix, aCustomProfileDir,
                            getter_AddRefs(mUpdate));
        mCoalesced = !!mUpdate;
    }

    if (!EnsureUpdate())
        return NS_ERROR_NULL_POINTER;

    mDocumentURI = aDocumentURI;
    mLoadingPrincipal = aLoadingPrincipal;

    if (aDocument)
        SetDocument(aDocument);

    if (mCoalesced) { // already initialized
        LOG(("OfflineCacheUpdateGlue %p coalesced with update %p", this, mUpdate.get()));
        return NS_OK;
    }

    return mUpdate->Init(aManifestURI, aDocumentURI, aLoadingPrincipal, nullptr,
                         aCustomProfileDir);
}

void
OfflineCacheUpdateGlue::SetDocument(nsIDOMDocument *aDocument)
{
    // The design is one document for one cache update on the content process.
    NS_ASSERTION(!mDocument, 
                 "Setting more then a single document on an instance of OfflineCacheUpdateGlue");

    LOG(("Document %p added to update glue %p", aDocument, this));

    // Add document only if it was not loaded from an offline cache.
    // If it were loaded from an offline cache then it has already
    // been associated with it and must not be again cached as
    // implicit (which are the reasons we collect documents here).
    nsCOMPtr<nsIDocument> document = do_QueryInterface(aDocument);
    if (!document)
        return;

    nsIChannel* channel = document->GetChannel();
    nsCOMPtr<nsIApplicationCacheChannel> appCacheChannel =
        do_QueryInterface(channel);
    if (!appCacheChannel)
        return;

    bool loadedFromAppCache;
    appCacheChannel->GetLoadedFromApplicationCache(&loadedFromAppCache);
    if (loadedFromAppCache)
        return;

    if (EnsureUpdate()) {
        mUpdate->StickDocument(mDocumentURI);
    }

    mDocument = aDocument;
}

NS_IMETHODIMP
OfflineCacheUpdateGlue::UpdateStateChanged(nsIOfflineCacheUpdate *aUpdate, uint32_t state)
{
    if (state == nsIOfflineCacheUpdateObserver::STATE_FINISHED) {
        LOG(("OfflineCacheUpdateGlue got STATE_FINISHED [%p]", this));

        nsCOMPtr<nsIObserverService> observerService =
          mozilla::services::GetObserverService();
        if (observerService) {
            LOG(("Calling offline-cache-update-completed"));
            observerService->NotifyObservers(static_cast<nsIOfflineCacheUpdate*>(this),
                                             "offline-cache-update-completed",
                                             nullptr);
            LOG(("Done offline-cache-update-completed"));
        }

        aUpdate->RemoveObserver(this);
    }

    return NS_OK;
}

NS_IMETHODIMP
OfflineCacheUpdateGlue::ApplicationCacheAvailable(nsIApplicationCache *aApplicationCache)
{
    NS_ENSURE_ARG(aApplicationCache);

    // Check that the document that requested this update was
    // previously associated with an application cache.  If not, it
    // should be associated with the new one.
    nsCOMPtr<nsIApplicationCacheContainer> container =
        do_QueryInterface(mDocument);
    if (!container)
        return NS_OK;

    nsCOMPtr<nsIApplicationCache> existingCache;
    nsresult rv = container->GetApplicationCache(getter_AddRefs(existingCache));
    NS_ENSURE_SUCCESS(rv, rv);

    if (!existingCache) {
        if (LOG_ENABLED()) {
            nsAutoCString clientID;
            if (aApplicationCache) {
                aApplicationCache->GetClientID(clientID);
            }
            LOG(("Update %p: associating app cache %s to document %p",
                 this, clientID.get(), mDocument.get()));
        }

        rv = container->SetApplicationCache(aApplicationCache);
        NS_ENSURE_SUCCESS(rv, rv);
    }

    return NS_OK;
}

} // namespace docshell
} // namespace mozilla
