/*
 * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
 * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
 * Copyright (C) Research In Motion Limited 2009. 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. 
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE 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 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.
 */

#ifndef FrameLoader_h
#define FrameLoader_h

#include "CachePolicy.h"
#include "FrameLoaderTypes.h"
#include "HistoryController.h"
#include "PolicyCallback.h"
#include "PolicyChecker.h"
#include "RedirectScheduler.h"
#include "ResourceLoadNotifier.h"
#include "ResourceRequest.h"
#include "ThreadableLoader.h"
#include "Timer.h"
#include <wtf/Forward.h>

namespace WebCore {

class Archive;
class AuthenticationChallenge;
class CachedFrameBase;
class CachedPage;
class CachedResource;
class DOMWrapperWorld;
class Document;
class DocumentLoader;
class Event;
class FormData;
class FormState;
class Frame;
class FrameLoaderClient;
class HistoryItem;
class HTMLAppletElement;
class HTMLFormElement;
class HTMLFrameOwnerElement;
class IconLoader;
class IntSize;
class NavigationAction;
class RenderEmbeddedObject;
class ResourceError;
class ResourceLoader;
class ResourceResponse;
class ScriptSourceCode;
class ScriptString;
class ScriptValue;
class SecurityOrigin;
class SerializedScriptValue;
class SharedBuffer;
class SubstituteData;
class TextResourceDecoder;
class Widget;

struct FrameLoadRequest;
struct WindowFeatures;

bool isBackForwardLoadType(FrameLoadType);

class FrameLoader : public Noncopyable {
public:
    FrameLoader(Frame*, FrameLoaderClient*);
    ~FrameLoader();

    void init();

    Frame* frame() const { return m_frame; }

    PolicyChecker* policyChecker() const { return &m_policyChecker; }
    HistoryController* history() const { return &m_history; }
    ResourceLoadNotifier* notifier() const { return &m_notifer; }

    // FIXME: This is not cool, people. There are too many different functions that all start loads.
    // We should aim to consolidate these into a smaller set of functions, and try to reuse more of
    // the logic by extracting common code paths.

    void prepareForLoadStart();
    void setupForReplace();
    void setupForReplaceByMIMEType(const String& newMIMEType);

    void loadURLIntoChildFrame(const KURL&, const String& referer, Frame*);

    void loadFrameRequest(const FrameLoadRequest&, bool lockHistory, bool lockBackForwardList,  // Called by submitForm, calls loadPostRequest and loadURL.
        PassRefPtr<Event>, PassRefPtr<FormState>, ReferrerPolicy);

    void load(const ResourceRequest&, bool lockHistory);                                        // Called by WebFrame, calls load(ResourceRequest, SubstituteData).
    void load(const ResourceRequest&, const SubstituteData&, bool lockHistory);                 // Called both by WebFrame and internally, calls load(DocumentLoader*).
    void load(const ResourceRequest&, const String& frameName, bool lockHistory);               // Called by WebPluginController.
    
    void loadArchive(PassRefPtr<Archive>);

    static void reportLocalLoadFailed(Frame*, const String& url);

    // Called by createWindow in JSDOMWindowBase.cpp, e.g. to fulfill a modal dialog creation
    Frame* createWindow(FrameLoader* frameLoaderForFrameLookup, const FrameLoadRequest&, const WindowFeatures&, bool& created);

    unsigned long loadResourceSynchronously(const ResourceRequest&, StoredCredentials, ResourceError&, ResourceResponse&, Vector<char>& data);

    bool canHandleRequest(const ResourceRequest&);

    // Also not cool.
    void stopAllLoaders(DatabasePolicy = DatabasePolicyStop);
    void stopForUserCancel(bool deferCheckLoadComplete = false);

    bool isLoadingMainResource() const { return m_isLoadingMainResource; }
    bool isLoading() const;
    bool frameHasLoaded() const;

    int numPendingOrLoadingRequests(bool recurse) const;
    String referrer() const;
    String outgoingReferrer() const;
    String outgoingOrigin() const;

    DocumentLoader* activeDocumentLoader() const;
    DocumentLoader* documentLoader() const { return m_documentLoader.get(); }
    DocumentLoader* policyDocumentLoader() const { return m_policyDocumentLoader.get(); }
    DocumentLoader* provisionalDocumentLoader() const { return m_provisionalDocumentLoader.get(); }
    FrameState state() const { return m_state; }
    static double timeOfLastCompletedLoad();

    bool shouldUseCredentialStorage(ResourceLoader*);
    const ResourceRequest& originalRequest() const;
    const ResourceRequest& initialRequest() const;
    void receivedMainResourceError(const ResourceError&, bool isComplete);
    void receivedData(const char*, int);

    bool willLoadMediaElementURL(KURL&);

    void handleFallbackContent();
    bool isStopping() const;

    void finishedLoading();

    ResourceError cancelledError(const ResourceRequest&) const;
    ResourceError fileDoesNotExistError(const ResourceResponse&) const;
    ResourceError blockedError(const ResourceRequest&) const;
    ResourceError cannotShowURLError(const ResourceRequest&) const;
    ResourceError interruptionForPolicyChangeError(const ResourceRequest&);

    bool isHostedByObjectElement() const;
    bool isLoadingMainFrame() const;
    bool canShowMIMEType(const String& MIMEType) const;
    bool representationExistsForURLScheme(const String& URLScheme);
    String generatedMIMETypeForURLScheme(const String& URLScheme);

    void reload(bool endToEndReload = false);
    void reloadWithOverrideEncoding(const String& overrideEncoding);

    void didReceiveServerRedirectForProvisionalLoadForFrame();
    void finishedLoadingDocument(DocumentLoader*);
    void committedLoad(DocumentLoader*, const char*, int);
    bool isReplacing() const;
    void setReplacing();
    void revertToProvisional(DocumentLoader*);
    void setMainDocumentError(DocumentLoader*, const ResourceError&);
    void mainReceivedCompleteError(DocumentLoader*, const ResourceError&);
    bool subframeIsLoading() const;
    void willChangeTitle(DocumentLoader*);
    void didChangeTitle(DocumentLoader*);

    FrameLoadType loadType() const;
    CachePolicy subresourceCachePolicy() const;

    void didFirstLayout();
    bool firstLayoutDone() const;

    void didFirstVisuallyNonEmptyLayout();

    void loadedResourceFromMemoryCache(const CachedResource*);
    void tellClientAboutPastMemoryCacheLoads();

    void checkLoadComplete();
    void detachFromParent();
    void detachViewsAndDocumentLoader();

    void addExtraFieldsToSubresourceRequest(ResourceRequest&);
    void addExtraFieldsToMainResourceRequest(ResourceRequest&);
    
    static void addHTTPOriginIfNeeded(ResourceRequest&, String origin);

    FrameLoaderClient* client() const { return m_client; }

    void setDefersLoading(bool);

    void changeLocation(const KURL&, const String& referrer, bool lockHistory = true, bool lockBackForwardList = true, bool userGesture = false, bool refresh = false);
    void urlSelected(const ResourceRequest&, const String& target, PassRefPtr<Event>, bool lockHistory, bool lockBackForwardList, bool userGesture, ReferrerPolicy);
    bool requestFrame(HTMLFrameOwnerElement*, const String& url, const AtomicString& frameName, bool lockHistory = true, bool lockBackForwardList = true);

    void submitForm(const char* action, const String& url,
        PassRefPtr<FormData>, const String& target, const String& contentType, const String& boundary,
        bool lockHistory, PassRefPtr<Event>, PassRefPtr<FormState>);

    void stop();
    void stopLoading(UnloadEventPolicy, DatabasePolicy = DatabasePolicyStop);
    bool closeURL();

    void didExplicitOpen();

    KURL iconURL();
    void commitIconURLToIconDatabase(const KURL&);

    KURL baseURL() const;

    void replaceDocument(const String&);

    void begin();
    void begin(const KURL&, bool dispatchWindowObjectAvailable = true, SecurityOrigin* forcedSecurityOrigin = 0);

    void write(const char* string, int length = -1, bool flush = false);
    void write(const String&);
    void end();
    void endIfNotLoadingMainResource();

    void setEncoding(const String& encoding, bool userChosen);
    String encoding() const;

    void tokenizerProcessedData();

    void handledOnloadEvents();
    String userAgent(const KURL&) const;

    PassRefPtr<Widget> createJavaAppletWidget(const IntSize&, HTMLAppletElement*, const HashMap<String, String>& args);

    void dispatchDidClearWindowObjectInWorld(DOMWrapperWorld*);
    void dispatchDidClearWindowObjectsInAllWorlds();
    void dispatchDocumentElementAvailable();

    void ownerElementSandboxFlagsChanged() { updateSandboxFlags(); }

    bool isSandboxed(SandboxFlags mask) const { return m_sandboxFlags & mask; }
    SandboxFlags sandboxFlags() const { return m_sandboxFlags; }

    // Mixed content related functions.
    static bool isMixedContent(SecurityOrigin* context, const KURL&);
    void checkIfDisplayInsecureContent(SecurityOrigin* context, const KURL&);
    void checkIfRunInsecureContent(SecurityOrigin* context, const KURL&);

    Frame* opener();
    void setOpener(Frame*);

    bool isProcessingUserGesture();

    void resetMultipleFormSubmissionProtection();

    void addData(const char* bytes, int length);

    void checkCallImplicitClose();

    void frameDetached();

    const KURL& url() const { return m_URL; }

    void setResponseMIMEType(const String&);
    const String& responseMIMEType() const;

    bool allowPlugins(ReasonForCallingAllowPlugins);
    bool containsPlugins() const;

    void loadDone();
    void finishedParsing();
    void checkCompleted();

    void checkDidPerformFirstNavigation();

    bool isComplete() const;

    bool requestObject(RenderEmbeddedObject*, const String& url, const AtomicString& frameName,
        const String& serviceType, const Vector<String>& paramNames, const Vector<String>& paramValues);

    KURL completeURL(const String& url);

    void cancelAndClear();

    void setTitle(const String&);

    void commitProvisionalLoad(PassRefPtr<CachedPage>);
    bool isLoadingFromCachedPage() const { return m_loadingFromCachedPage; }

    bool committingFirstRealLoad() const { return !m_creatingInitialEmptyDocument && !m_committedFirstRealDocumentLoad; }
    bool committedFirstRealDocumentLoad() const { return m_committedFirstRealDocumentLoad; }
    bool creatingInitialEmptyDocument() const { return m_creatingInitialEmptyDocument; }

    void iconLoadDecisionAvailable();

    bool shouldAllowNavigation(Frame* targetFrame) const;
    Frame* findFrameForNavigation(const AtomicString& name);

    void startIconLoader();

    void applyUserAgent(ResourceRequest& request);

    bool shouldInterruptLoadForXFrameOptions(const String&, const KURL&);

    void open(CachedFrameBase&);

    // FIXME: Should these really be public?
    void completed();
    bool allAncestorsAreComplete() const; // including this
    bool allChildrenAreComplete() const; // immediate children, not all descendants
    void clientRedirected(const KURL&, double delay, double fireDate, bool lockBackForwardList);
    void clientRedirectCancelledOrFinished(bool cancelWithLoadInProgress);
    void loadItem(HistoryItem*, FrameLoadType);

    // FIXME: This is public because this asynchronous callback from the FrameLoaderClient
    // uses the policy machinery (and therefore is called via the PolicyChecker).  Once we
    // introduce a proper callback type for this function, we should make it private again.
    void continueLoadAfterWillSubmitForm();
    
    bool suppressOpenerInNewFrame() const { return m_suppressOpenerInNewFrame; }

    static ObjectContentType defaultObjectContentType(const KURL& url, const String& mimeType);

private:
    bool canCachePageContainingThisFrame();
#ifndef NDEBUG
    void logCanCachePageDecision();
    bool logCanCacheFrameDecision(int indentLevel);
#endif

    void checkTimerFired(Timer<FrameLoader>*);

    void started();

    bool shouldUsePlugin(const KURL&, const String& mimeType, bool hasFallback, bool& useFallback);
    bool loadPlugin(RenderEmbeddedObject*, const KURL&, const String& mimeType,
        const Vector<String>& paramNames, const Vector<String>& paramValues, bool useFallback);
    
    void navigateWithinDocument(HistoryItem*);
    void navigateToDifferentDocument(HistoryItem*, FrameLoadType);
    
    bool loadProvisionalItemFromCachedPage();
    void cachePageForHistoryItem(HistoryItem*);
    void pageHidden();

    void receivedFirstData();

    void updateFirstPartyForCookies();
    void setFirstPartyForCookies(const KURL&);
    
    void addExtraFieldsToRequest(ResourceRequest&, FrameLoadType loadType, bool isMainResource, bool cookiePolicyURLFromRequest);

    // Also not cool.
    void stopLoadingSubframes();

    void clearProvisionalLoad();
    void markLoadComplete();
    void transitionToCommitted(PassRefPtr<CachedPage>);
    void frameLoadCompleted();

    void mainReceivedError(const ResourceError&, bool isComplete);

    void setLoadType(FrameLoadType);

    static void callContinueLoadAfterNavigationPolicy(void*, const ResourceRequest&, PassRefPtr<FormState>, bool shouldContinue);
    static void callContinueLoadAfterNewWindowPolicy(void*, const ResourceRequest&, PassRefPtr<FormState>, const String& frameName, bool shouldContinue);
    static void callContinueFragmentScrollAfterNavigationPolicy(void*, const ResourceRequest&, PassRefPtr<FormState>, bool shouldContinue);

    void continueLoadAfterNavigationPolicy(const ResourceRequest&, PassRefPtr<FormState>, bool shouldContinue);
    void continueLoadAfterNewWindowPolicy(const ResourceRequest&, PassRefPtr<FormState>, const String& frameName, bool shouldContinue);
    void continueFragmentScrollAfterNavigationPolicy(const ResourceRequest&, bool shouldContinue);

    bool shouldScrollToAnchor(bool isFormSubmission, FrameLoadType, const KURL&);

    void checkLoadCompleteForThisFrame();

    void setDocumentLoader(DocumentLoader*);
    void setPolicyDocumentLoader(DocumentLoader*);
    void setProvisionalDocumentLoader(DocumentLoader*);

    void setState(FrameState);

    void closeOldDataSources();
    void open(CachedPage&);

    void updateHistoryAfterClientRedirect();

    void clear(bool clearWindowProperties = true, bool clearScriptObjects = true, bool clearFrameView = true);

    bool shouldReloadToHandleUnreachableURL(DocumentLoader*);

    void dispatchDidCommitLoad();

    void loadWithDocumentLoader(DocumentLoader*, FrameLoadType, PassRefPtr<FormState>); // Calls continueLoadAfterNavigationPolicy
    void load(DocumentLoader*);                                                         // Calls loadWithDocumentLoader   

    void loadWithNavigationAction(const ResourceRequest&, const NavigationAction&,      // Calls loadWithDocumentLoader
        bool lockHistory, FrameLoadType, PassRefPtr<FormState>);

    void loadPostRequest(const ResourceRequest&, const String& referrer,                // Called by loadFrameRequest, calls loadWithNavigationAction
        const String& frameName, bool lockHistory, FrameLoadType, PassRefPtr<Event>, PassRefPtr<FormState>);
    void loadURL(const KURL&, const String& referrer, const String& frameName,          // Called by loadFrameRequest, calls loadWithNavigationAction or dispatches to navigation policy delegate
        bool lockHistory, FrameLoadType, PassRefPtr<Event>, PassRefPtr<FormState>);                                                         

    bool shouldReload(const KURL& currentURL, const KURL& destinationURL);

    void requestFromDelegate(ResourceRequest&, unsigned long& identifier, ResourceError&);

    void recursiveCheckLoadComplete();

    void detachChildren();
    void closeAndRemoveChild(Frame*);

    Frame* loadSubframe(HTMLFrameOwnerElement*, const KURL&, const String& name, const String& referrer);

    void loadInSameDocument(const KURL&, SerializedScriptValue* stateObject, bool isNewNavigation);

    void provisionalLoadStarted();

    bool canCachePage();

    bool didOpenURL(const KURL&);

    void scheduleCheckCompleted();
    void scheduleCheckLoadComplete();
    void startCheckCompleteTimer();

    KURL originalRequestURL() const;

    bool shouldTreatURLAsSameAsCurrent(const KURL&) const;

    void updateSandboxFlags();
    // FIXME: isDocumentSandboxed should eventually replace isSandboxed.
    bool isDocumentSandboxed(SandboxFlags) const;

    Frame* m_frame;
    FrameLoaderClient* m_client;

    mutable PolicyChecker m_policyChecker;
    mutable HistoryController m_history;
    mutable ResourceLoadNotifier m_notifer;

    FrameState m_state;
    FrameLoadType m_loadType;

    // Document loaders for the three phases of frame loading. Note that while 
    // a new request is being loaded, the old document loader may still be referenced.
    // E.g. while a new request is in the "policy" state, the old document loader may
    // be consulted in particular as it makes sense to imply certain settings on the new loader.
    RefPtr<DocumentLoader> m_documentLoader;
    RefPtr<DocumentLoader> m_provisionalDocumentLoader;
    RefPtr<DocumentLoader> m_policyDocumentLoader;

    bool m_delegateIsHandlingProvisionalLoadError;

    bool m_firstLayoutDone;
    bool m_quickRedirectComing;
    bool m_sentRedirectNotification;
    bool m_inStopAllLoaders;

    String m_outgoingReferrer;

    bool m_isExecutingJavaScriptFormAction;

    String m_responseMIMEType;

    bool m_didCallImplicitClose;
    bool m_wasUnloadEventEmitted;
    bool m_unloadEventBeingDispatched;
    bool m_isComplete;
    bool m_isLoadingMainResource;

    RefPtr<SerializedScriptValue> m_pendingStateObject;

    KURL m_URL;
    KURL m_workingURL;

    OwnPtr<IconLoader> m_iconLoader;
    bool m_mayLoadIconLater;

    bool m_cancellingWithLoadInProgress;

    bool m_needsClear;
    bool m_receivedData;

    bool m_encodingWasChosenByUser;
    String m_encoding;
    RefPtr<TextResourceDecoder> m_decoder;

    bool m_containsPlugIns;

    KURL m_submittedFormURL;

    Timer<FrameLoader> m_checkTimer;
    bool m_shouldCallCheckCompleted;
    bool m_shouldCallCheckLoadComplete;

    Frame* m_opener;
    HashSet<Frame*> m_openedFrames;

    bool m_creatingInitialEmptyDocument;
    bool m_isDisplayingInitialEmptyDocument;
    bool m_committedFirstRealDocumentLoad;

    bool m_didPerformFirstNavigation;
    bool m_loadingFromCachedPage;
    bool m_suppressOpenerInNewFrame;
    
    SandboxFlags m_sandboxFlags;

#ifndef NDEBUG
    bool m_didDispatchDidCommitLoad;
#endif
};

} // namespace WebCore

#endif // FrameLoader_h
