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 * for the specific language governing rights and limitations under the
 * License.
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 * The Original Code is mozilla.org code.
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 *
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#include "nsImgManager.h"
#include "nsImages.h"
#include "nsIDocument.h"
#include "nsIContent.h"
#include "nsCOMPtr.h"
#include "nsXPIDLString.h"
#include "nsIURI.h"
#include "nsNetCID.h"
#include "nsIServiceManager.h"
#include "nsIScriptGlobalObject.h"
#include "nsIDOMWindow.h"
#include "nsIDocShellTreeItem.h"

static NS_DEFINE_CID(kIOServiceCID, NS_IOSERVICE_CID);

static PRBool ShouldBlockImageByScheme(nsIURI * aURI)
{
    nsCAutoString scheme;

    if (NS_FAILED(aURI->GetScheme(scheme)))
      return PR_FALSE;

    return scheme.Equals(NS_LITERAL_CSTRING("http")) || scheme.Equals(NS_LITERAL_CSTRING("https")) ||
           scheme.Equals(NS_LITERAL_CSTRING("imap")) || scheme.Equals(NS_LITERAL_CSTRING("mailbox")) ||
           scheme.Equals(NS_LITERAL_CSTRING("news")) || scheme.Equals(NS_LITERAL_CSTRING("snews"));
}


////////////////////////////////////////////////////////////////////////////////


////////////////////////////////////////////////////////////////////////////////
// nsImgManager Implementation

NS_IMPL_ISUPPORTS2(nsImgManager, 
                   nsIImgManager, 
                   nsIContentPolicy);

nsImgManager::nsImgManager()
{
    NS_INIT_REFCNT();
}

nsImgManager::~nsImgManager(void)
{
}

nsresult nsImgManager::Init()
{
    IMAGE_RegisterPrefCallbacks();
    nsresult rv;
    mIOService = do_GetService(NS_IOSERVICE_CONTRACTID, &rv);
    return rv;
}


NS_IMETHODIMP nsImgManager::Block(const char * imageURL)
{
    ::IMAGE_Block(imageURL,mIOService);
    return NS_OK;
}


// nsIContentPolicy Implementation
NS_IMETHODIMP nsImgManager::ShouldLoad(PRInt32 aContentType, 
                                       nsIURI *aContentLoc,
                                       nsISupports *aContext,
                                       nsIDOMWindow *aWindow,
                                       PRBool *_retval)
{
    *_retval = PR_TRUE;
    nsresult rv = NS_OK;

    // we can't do anything w/ out these.
    if (!aContentLoc || !aContext) return rv;

    switch (aContentType) {
        case nsIContentPolicy::IMAGE:   
        {
            // First, let be sure we are processing an HTTP or HTTPS images.
            // We should not waste time with chrome url...
            PRBool httpType;
            rv = aContentLoc->SchemeIs("http", &httpType);
            if (NS_FAILED(rv) || !httpType) {
                // check HTTPS as well
                rv = aContentLoc->SchemeIs("https", &httpType);
                if (NS_FAILED(rv) || !httpType) return rv;
            }

            nsCOMPtr<nsIURI> baseURI;
            nsCOMPtr<nsIDocument> doc;
            nsCOMPtr<nsIContent> content(do_QueryInterface(aContext));
            NS_ASSERTION(content, "no content avail");
            if (content) {
                rv = content->GetDocument(*getter_AddRefs(doc));
                if (NS_FAILED(rv) || !doc) return rv;

                rv = doc->GetBaseURL(*getter_AddRefs(baseURI));
                if (NS_FAILED(rv) || !baseURI) return rv;

                if (!ShouldBlockImageByScheme(baseURI)) //JFD: Why do we care about the base url anyway?
                  return NS_OK;

                // Let check if we are running a mail window, doesn't matter if mail images are allowed
                if (IMAGE_BlockedInMail()) {
                    nsCOMPtr<nsIDocShell> docshell;
                    rv = GetRootDocShell(aWindow, getter_AddRefs(docshell));
                    if (docshell) {
                        PRUint32 appType;
                        rv = docshell->GetAppType(&appType);
                        if (NS_SUCCEEDED(rv) && appType == nsIDocShell::APP_TYPE_MAIL) {
                            //we are dealing with an mail or newsgroup window, let's block the image
                            *_retval = PR_FALSE;
                            return NS_OK;
                        }
                    }
                }

                nsCAutoString baseHost;
                rv = baseURI->GetAsciiHost(baseHost);
                if (NS_FAILED(rv)) return rv;

                nsCAutoString host;
                rv = aContentLoc->GetAsciiHost(host);
                if (NS_FAILED(rv)) return rv;

                return ::IMAGE_CheckForPermission(host.get(), baseHost.get(),
                                                  _retval);
            }
        }
        break;
    }
    return NS_OK;
}

NS_IMETHODIMP nsImgManager::ShouldProcess(PRInt32 aContentType,
                                          nsIURI *aDocumentLoc,
                                          nsISupports *aContext,
                                          nsIDOMWindow *aWindow,
                                          PRBool *_retval) {
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP nsImgManager::GetRootDocShell(nsIDOMWindow *aWindow, nsIDocShell **result)
{
  nsresult rv;

  nsCOMPtr<nsIScriptGlobalObject> globalObj;
  aWindow->QueryInterface(NS_GET_IID(nsIScriptGlobalObject), getter_AddRefs(globalObj));
  if (!globalObj)
    return NS_ERROR_FAILURE;

  nsCOMPtr<nsIDocShell> docshell;
  rv = globalObj->GetDocShell(getter_AddRefs(docshell));
  if (NS_FAILED(rv))
    return rv;

  nsCOMPtr<nsIDocShellTreeItem> docshellTreeItem(do_QueryInterface(docshell, &rv));
  if (NS_FAILED(rv))
    return rv;

  nsCOMPtr<nsIDocShellTreeItem> rootItem;
  rv = docshellTreeItem->GetRootTreeItem(getter_AddRefs(rootItem));
  if (NS_FAILED(rv))
    return rv;

  return rootItem->QueryInterface(NS_GET_IID(nsIDocShell), (void **)result);
}