/* -*- Mode: C++; tab-width: 2; 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/. */

#ifndef nsAboutCache_h__
#define nsAboutCache_h__

#include "nsIAboutModule.h"
#include "nsICacheStorageVisitor.h"
#include "nsICacheStorage.h"

#include "nsString.h"
#include "nsIOutputStream.h"
#include "nsILoadContextInfo.h"

#include "nsCOMPtr.h"
#include "nsTArray.h"

#define NS_FORWARD_SAFE_NSICHANNEL_SUBSET(_to) \
  NS_IMETHOD GetOriginalURI(nsIURI * *aOriginalURI) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetOriginalURI(aOriginalURI); } \
  NS_IMETHOD SetOriginalURI(nsIURI *aOriginalURI) override { return !_to ? NS_ERROR_NULL_POINTER : _to->SetOriginalURI(aOriginalURI); } \
  NS_IMETHOD GetURI(nsIURI * *aURI) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetURI(aURI); } \
  NS_IMETHOD GetOwner(nsISupports * *aOwner) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetOwner(aOwner); } \
  NS_IMETHOD SetOwner(nsISupports *aOwner) override { return !_to ? NS_ERROR_NULL_POINTER : _to->SetOwner(aOwner); } \
  NS_IMETHOD GetNotificationCallbacks(nsIInterfaceRequestor * *aNotificationCallbacks) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetNotificationCallbacks(aNotificationCallbacks); } \
  NS_IMETHOD SetNotificationCallbacks(nsIInterfaceRequestor *aNotificationCallbacks) override { return !_to ? NS_ERROR_NULL_POINTER : _to->SetNotificationCallbacks(aNotificationCallbacks); } \
  NS_IMETHOD GetSecurityInfo(nsISupports * *aSecurityInfo) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetSecurityInfo(aSecurityInfo); } \
  NS_IMETHOD GetContentType(nsACString & aContentType) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetContentType(aContentType); } \
  NS_IMETHOD SetContentType(const nsACString & aContentType) override { return !_to ? NS_ERROR_NULL_POINTER : _to->SetContentType(aContentType); } \
  NS_IMETHOD GetContentCharset(nsACString & aContentCharset) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetContentCharset(aContentCharset); } \
  NS_IMETHOD SetContentCharset(const nsACString & aContentCharset) override { return !_to ? NS_ERROR_NULL_POINTER : _to->SetContentCharset(aContentCharset); } \
  NS_IMETHOD GetContentLength(int64_t *aContentLength) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetContentLength(aContentLength); } \
  NS_IMETHOD SetContentLength(int64_t aContentLength) override { return !_to ? NS_ERROR_NULL_POINTER : _to->SetContentLength(aContentLength); } \
  NS_IMETHOD GetContentDisposition(uint32_t *aContentDisposition) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetContentDisposition(aContentDisposition); } \
  NS_IMETHOD SetContentDisposition(uint32_t aContentDisposition) override { return !_to ? NS_ERROR_NULL_POINTER : _to->SetContentDisposition(aContentDisposition); } \
  NS_IMETHOD GetContentDispositionFilename(nsAString & aContentDispositionFilename) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetContentDispositionFilename(aContentDispositionFilename); } \
  NS_IMETHOD SetContentDispositionFilename(const nsAString & aContentDispositionFilename) override { return !_to ? NS_ERROR_NULL_POINTER : _to->SetContentDispositionFilename(aContentDispositionFilename); } \
  NS_IMETHOD GetContentDispositionHeader(nsACString & aContentDispositionHeader) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetContentDispositionHeader(aContentDispositionHeader); } \
  NS_IMETHOD GetLoadInfo(nsILoadInfo * *aLoadInfo) override { return !_to ? NS_ERROR_NULL_POINTER : _to->GetLoadInfo(aLoadInfo); } \
  NS_IMETHOD SetLoadInfo(nsILoadInfo *aLoadInfo) override { return !_to ? NS_ERROR_NULL_POINTER : _to->SetLoadInfo(aLoadInfo); } \

class nsAboutCache final : public nsIAboutModule
{
public:
    NS_DECL_ISUPPORTS
    NS_DECL_NSIABOUTMODULE

    nsAboutCache() {}

    static nsresult
    Create(nsISupports *aOuter, REFNSIID aIID, void **aResult);

    static nsresult
    GetStorage(nsACString const & storageName, nsILoadContextInfo* loadInfo,
               nsICacheStorage **storage);

protected:
    virtual ~nsAboutCache() {}

    class Channel final : public nsIChannel
                        , public nsICacheStorageVisitor
    {
        NS_DECL_ISUPPORTS
        NS_DECL_NSICACHESTORAGEVISITOR
        NS_FORWARD_SAFE_NSIREQUEST(mChannel)
        NS_FORWARD_SAFE_NSICHANNEL_SUBSET(mChannel)
        NS_IMETHOD AsyncOpen(nsIStreamListener *aListener, nsISupports *aContext) override;
        NS_IMETHOD AsyncOpen2(nsIStreamListener *aListener) override;
        NS_IMETHOD Open(nsIInputStream * *_retval) override;
        NS_IMETHOD Open2(nsIInputStream * *_retval) override;

    private:
        virtual ~Channel() {}

    public:
        nsresult Init(nsIURI* aURI, nsILoadInfo* aLoadInfo);
        nsresult ParseURI(nsIURI * uri, nsACString & storage);

        // Finds a next storage we wish to visit (we use this method
        // even there is a specified storage name, which is the only
        // one in the list then.)  Posts FireVisitStorage() when found.
        nsresult VisitNextStorage();
        // Helper method that calls VisitStorage() for the current storage.
        // When it fails, OnCacheEntryVisitCompleted is simulated to close
        // the output stream and thus the about:cache channel.
        void FireVisitStorage();
        // Kiks the visit cycle for the given storage, names can be:
        // "disk", "memory", "appcache"
        // Note: any newly added storage type has to be manually handled here.
        nsresult VisitStorage(nsACString const & storageName);

        // Writes content of mBuffer to mStream and truncates
        // the buffer.  It may fail when the input stream is closed by canceling
        // the input stream channel.  It can be used to stop the cache iteration
        // process.
        nsresult FlushBuffer();

        // Whether we are showing overview status of all available
        // storages.
        bool mOverview;

        // Flag initially false, that indicates the entries header has
        // been added to the output HTML.
        bool mEntriesHeaderAdded;

        // Cancelation flag
        bool mCancel;

        // The context we are working with.
        nsCOMPtr<nsILoadContextInfo> mLoadInfo;
        nsCString mContextString;

        // The list of all storage names we want to visit
        nsTArray<nsCString> mStorageList;
        nsCString mStorageName;
        nsCOMPtr<nsICacheStorage> mStorage;

        // Output data buffering and streaming output
        nsCString mBuffer;
        nsCOMPtr<nsIOutputStream> mStream;

        // The input stream channel, the one that actually does the job
        nsCOMPtr<nsIChannel> mChannel;
    };
};

#define NS_ABOUT_CACHE_MODULE_CID                    \
{ /* 9158c470-86e4-11d4-9be2-00e09872a416 */         \
    0x9158c470,                                      \
    0x86e4,                                          \
    0x11d4,                                          \
    {0x9b, 0xe2, 0x00, 0xe0, 0x98, 0x72, 0xa4, 0x16} \
}

#endif // nsAboutCache_h__
