/*
 * Copyright (C) 2016 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "PendingDownload.h"

#include "Download.h"
#include "DownloadProxyMessages.h"
#include "MessageSenderInlines.h"
#include "NetworkConnectionToWebProcess.h"
#include "NetworkLoad.h"
#include "NetworkProcess.h"
#include "NetworkSession.h"
#include "WebErrors.h"
#include <WebCore/LocalFrameLoaderClient.h>
#include <wtf/TZoneMallocInlines.h>

namespace WebKit {
using namespace WebCore;

WTF_MAKE_TZONE_ALLOCATED_IMPL(PendingDownload);

PendingDownload::PendingDownload(IPC::Connection* parentProcessConnection, NetworkLoadParameters&& parameters, DownloadID downloadID, NetworkSession& networkSession, const String& suggestedName, FromDownloadAttribute fromDownloadAttribute, std::optional<WebCore::ProcessIdentifier> webProcessID)
    : m_networkLoad(NetworkLoad::create(*this, WTFMove(parameters), networkSession))
    , m_downloadID(downloadID)
    , m_parentProcessConnection(parentProcessConnection)
    , m_fromDownloadAttribute(fromDownloadAttribute)
    , m_webProcessID(webProcessID)
{
    relaxAdoptionRequirement();

#if ENABLE(CONTENT_FILTERING)
    NetworkProcess::setSharedParentalControlsURLFilterIfNecessary();
#endif

#if HAVE(WEBCONTENTRESTRICTIONS)
#if HAVE(WEBCONTENTRESTRICTIONS_PATH_SPI)
    m_urlFilter = ParentalControlsURLFilter::filterWithConfigurationPath(networkSession.webContentRestrictionsConfigurationFile());
#else
    m_urlFilter = ParentalControlsURLFilter::singleton();
#endif // HAVE(WEBCONTENTRESTRICTIONS_PATH_SPI)
#endif // HAVE(WEBCONTENTRESTRICTIONS)

    auto startNetworkLoad = [this, protectedThis = Ref { *this }, downloadID, suggestedName] () {
        m_networkLoad->start();
        m_isAllowedToAskUserForCredentials = m_networkLoad->parameters().clientCredentialPolicy == ClientCredentialPolicy::MayAskClientForCredentials;

        m_networkLoad->setPendingDownloadID(downloadID);
        m_networkLoad->setPendingDownload(*this);
        m_networkLoad->setSuggestedFilename(suggestedName);
    };

    send(Messages::DownloadProxy::DidStart(m_networkLoad->currentRequest(), suggestedName));

#if HAVE(WEBCONTENTRESTRICTIONS)
    m_urlFilter->isURLAllowed(m_networkLoad->currentRequest().url(), [this, protectedThis = Ref { *this }, startNetworkLoad = WTFMove(startNetworkLoad)] (bool allowed, NSData *) mutable {
        if (!allowed) {
            blockDueToContentFilter(ResourceResponse { m_networkLoad->currentRequest().url(), "application/octet-stream"_s, 0, ""_s }, nullptr);
            return;
        }

        startNetworkLoad();
    });
#else
    startNetworkLoad();
#endif
}

PendingDownload::PendingDownload(IPC::Connection* parentProcessConnection, Ref<NetworkLoad>&& networkLoad, ResponseCompletionHandler&& completionHandler, DownloadID downloadID, const ResourceRequest& request, const ResourceResponse& response)
    : m_networkLoad(WTFMove(networkLoad))
    , m_downloadID(downloadID)
    , m_parentProcessConnection(parentProcessConnection)
{
    m_isAllowedToAskUserForCredentials = m_networkLoad->isAllowedToAskUserForCredentials();

    m_networkLoad->setPendingDownloadID(downloadID);
    send(Messages::DownloadProxy::DidStart(request, String()));

    m_networkLoad->convertTaskToDownload(*this, request, response, WTFMove(completionHandler));
}

PendingDownload::~PendingDownload() = default;

bool PendingDownload::isDownloadTriggeredWithDownloadAttribute() const
{
    return m_fromDownloadAttribute == FromDownloadAttribute::Yes;
}

inline static bool isRedirectCrossOrigin(const WebCore::ResourceRequest& redirectRequest, const WebCore::ResourceResponse& redirectResponse)
{
    return !SecurityOrigin::create(redirectResponse.url())->isSameOriginAs(SecurityOrigin::create(redirectRequest.url()));
}

void PendingDownload::willSendRedirectedRequest(WebCore::ResourceRequest&&, WebCore::ResourceRequest&& redirectRequest, WebCore::ResourceResponse&& redirectResponse, CompletionHandler<void(WebCore::ResourceRequest&&)>&& completionHandler)
{
#if PLATFORM(COCOA)
    bool linkedOnOrAfterBlockCrossOriginDownloads = WTF::linkedOnOrAfterSDKWithBehavior(SDKAlignedBehavior::BlockCrossOriginRedirectDownloads);
#else
    bool linkedOnOrAfterBlockCrossOriginDownloads = true;
#endif
    if (linkedOnOrAfterBlockCrossOriginDownloads && isDownloadTriggeredWithDownloadAttribute() && isRedirectCrossOrigin(redirectRequest, redirectResponse)) {
        completionHandler(WebCore::ResourceRequest());
        m_networkLoad->cancel();
        if (m_webProcessID && !redirectRequest.url().protocolIsJavaScript() && m_networkLoad->webFrameID() && m_networkLoad->webPageID())
            m_networkLoad->networkProcess()->protectedWebProcessConnection(*m_webProcessID)->loadCancelledDownloadRedirectRequestInFrame(redirectRequest, *m_networkLoad->webFrameID(), *m_networkLoad->webPageID());
        return;
    }

#if HAVE(WEBCONTENTRESTRICTIONS)
    auto requestURL = redirectRequest.url();
    m_urlFilter->isURLAllowed(requestURL, [this, protectedThis = Ref { *this }, completionHandler = WTFMove(completionHandler), redirectRequest = WTFMove(redirectRequest), redirectResponse = WTFMove(redirectResponse)] (bool allowed, NSData *) mutable {
        if (allowed) {
            sendWithAsyncReply(Messages::DownloadProxy::WillSendRequest(WTFMove(redirectRequest), WTFMove(redirectResponse)), WTFMove(completionHandler));
            return;
        }

        blockDueToContentFilter(redirectResponse, [completionHandler = WTFMove(completionHandler)] () mutable {
            completionHandler(ResourceRequest { });
        });
    });
#else
    sendWithAsyncReply(Messages::DownloadProxy::WillSendRequest(WTFMove(redirectRequest), WTFMove(redirectResponse)), WTFMove(completionHandler));
#endif // HAVE(WEBCONTENTRESTRICTIONS)
};

void PendingDownload::cancel(CompletionHandler<void(std::span<const uint8_t>)>&& completionHandler)
{
    m_networkLoad->cancel();
    completionHandler({ });
}

#if PLATFORM(COCOA)
#if HAVE(MODERN_DOWNLOADPROGRESS)
void PendingDownload::publishProgress(const URL& url, std::span<const uint8_t> bookmarkData, UseDownloadPlaceholder useDownloadPlaceholder, std::span<const uint8_t> activityAccessToken)
{
    ASSERT(!m_progressURL.isValid());
    m_progressURL = url;
    m_bookmarkData = bookmarkData;
    m_useDownloadPlaceholder = useDownloadPlaceholder;
    m_activityAccessToken = activityAccessToken;
}
#else
void PendingDownload::publishProgress(const URL& url, SandboxExtension::Handle&& sandboxExtension)
{
    ASSERT(!m_progressURL.isValid());
    m_progressURL = url;
    m_progressSandboxExtension = WTFMove(sandboxExtension);
}
#endif

void PendingDownload::didBecomeDownload(Download& download)
{
    if (!m_progressURL.isValid())
        return;
#if HAVE(MODERN_DOWNLOADPROGRESS)
    download.publishProgress(m_progressURL, m_bookmarkData, m_useDownloadPlaceholder, m_activityAccessToken);
#else
    download.publishProgress(m_progressURL, WTFMove(m_progressSandboxExtension));
#endif
}
#endif // PLATFORM(COCOA)

void PendingDownload::didFailLoading(const WebCore::ResourceError& error)
{
    // FIXME: For Cross Origin redirects Cancellation happens early. So avoid repeating. Maybe there is a better way ?
    if (!m_isDownloadCancelled) {
        m_isDownloadCancelled = true;
        send(Messages::DownloadProxy::DidFail(error, { }));
    }
}
    
IPC::Connection* PendingDownload::messageSenderConnection() const
{
    return m_parentProcessConnection.get();
}

void PendingDownload::didReceiveResponse(WebCore::ResourceResponse&& response, PrivateRelayed, ResponseCompletionHandler&& completionHandler)
{
    completionHandler(WebCore::PolicyAction::Download);
}

uint64_t PendingDownload::messageSenderDestinationID() const
{
    return m_downloadID.toUInt64();
}

#if HAVE(WEBCONTENTRESTRICTIONS)
void PendingDownload::blockDueToContentFilter(const WebCore::ResourceResponse& response, CompletionHandler<void()>&& postBlockHandler)
{
    if (m_wasBlockedDueToContentFilter) {
        postBlockHandler();
        return;
    }
    
    m_wasBlockedDueToContentFilter = true;

    auto currentRequest = m_networkLoad->currentRequest();

    // Whenever the content filter blocks a PendingDownload, the download hasn't made it to the stage
    // where the UI client is asked to decide a filename.
    // Therefore the UI client doesn't even know about the download yet, and can't track its
    // status of being "blocked"
    // So we ask it to decide the filename, after which we can report it being blocked.
    sendWithAsyncReply(Messages::DownloadProxy::DecideDestinationWithSuggestedFilename(response, response.suggestedFilename()), [this, protectedThis = Ref { *this }, currentRequest, postBlockHandler = WTFMove(postBlockHandler)] (String&& name, SandboxExtension::Handle&&, AllowOverwrite, WebKit::UseDownloadPlaceholder, URL&&, SandboxExtension::Handle&&, std::span<const uint8_t>, std::span<const uint8_t>) mutable {
        didFailLoading(blockedByContentFilterError(currentRequest));

        m_networkLoad->cancel();
        if (postBlockHandler)
            postBlockHandler();
    }, m_downloadID);
}
#endif // HAVE(WEBCONTENTRESTRICTIONS)

}