// vim:ts=2:sw=2:et:
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is cookie manager code.
 *
 * The Initial Developer of the Original Code is
 * Michiel van Leeuwen (mvl@exedo.nl).
 * Portions created by the Initial Developer are Copyright (C) 2003
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Darin Fisher <darin@meer.net>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */


#include "nsCookiePermission.h"
#include "nsICookie2.h"
#include "nsIServiceManager.h"
#include "nsICookiePromptService.h"
#include "nsICookieManager2.h"
#include "nsCCookieManager.h"
#include "nsIURI.h"
#include "nsIPrefService.h"
#include "nsIPrefBranch.h"
#include "nsIPrefBranchInternal.h"
#include "nsIDocShell.h"
#include "nsIDocShellTreeItem.h"
#include "nsIInterfaceRequestor.h"
#include "nsIInterfaceRequestorUtils.h"
#include "nsILoadGroup.h"
#include "nsIChannel.h"
#include "nsIDOMWindow.h"
#include "nsString.h"
#include "nsInt64.h"
#include "prtime.h"

/****************************************************************
 ************************ nsCookiePermission ********************
 ****************************************************************/

static const PRBool kDefaultPolicy = PR_TRUE;
static const char kCookiesAskPermission[] = "network.cookie.warnAboutCookies";
static const char kCookiesDisabledForMailNews[] = "network.cookie.disableCookieForMailNews";
static const char kPermissionType[] = "cookie";

// XXX these casts and constructs are horrible, but our nsInt64/nsTime
// classes are lacking so we need them for now. see bug 198694.
#define USEC_PER_SEC   (nsInt64(1000000))
#define NOW_IN_SECONDS (nsInt64(PR_Now()) / USEC_PER_SEC)

#ifndef MOZ_PHOENIX
// returns PR_TRUE if URI appears to be the URI of a mailnews protocol
static PRBool
IsFromMailNews(nsIURI *aURI)
{
  static const char *kMailNewsProtocols[] =
      { "imap", "news", "snews", "mailbox", nsnull };
  PRBool result;
  for (const char **p = kMailNewsProtocols; *p; ++p) {
    if (NS_SUCCEEDED(aURI->SchemeIs(*p, &result)) && result)
      return PR_TRUE;
  }
  return PR_FALSE;
}
#endif

static void
GetInterfaceFromChannel(nsIChannel   *aChannel,
                        const nsIID  &aIID,
                        void        **aResult)
{
  if (!aChannel)
    return; // no context, no interface!
  NS_ASSERTION(!*aResult, "result not initialized to null");

  nsCOMPtr<nsIInterfaceRequestor> cbs;
  aChannel->GetNotificationCallbacks(getter_AddRefs(cbs));
  if (cbs)
    cbs->GetInterface(aIID, aResult);
  if (!*aResult) {
    // try load group's notification callbacks...
    nsCOMPtr<nsILoadGroup> loadGroup;
    aChannel->GetLoadGroup(getter_AddRefs(loadGroup));
    if (loadGroup) {
      loadGroup->GetNotificationCallbacks(getter_AddRefs(cbs));
      if (cbs)
        cbs->GetInterface(aIID, aResult);
    }
  }
}

NS_IMPL_ISUPPORTS2(nsCookiePermission,
                   nsICookiePermission,
                   nsIObserver)

nsresult
nsCookiePermission::Init()
{
  nsresult rv;
  mPermMgr = do_GetService(NS_PERMISSIONMANAGER_CONTRACTID, &rv);
  if (NS_FAILED(rv)) return rv;

  // failure to access the pref service is non-fatal...
  nsCOMPtr<nsIPrefBranch> prefBranch =
      do_GetService(NS_PREFSERVICE_CONTRACTID);
  if (prefBranch) {
    nsCOMPtr<nsIPrefBranchInternal> prefInt = do_QueryInterface(prefBranch);   
    if (prefInt) {
      prefInt->AddObserver(kCookiesAskPermission, this, PR_FALSE);
      prefInt->AddObserver(kCookiesDisabledForMailNews, this, PR_FALSE);
    }
    PrefChanged(prefBranch, nsnull);
  }

  return NS_OK;
}

void
nsCookiePermission::PrefChanged(nsIPrefBranch *prefBranch,
                                const char    *pref)
{
  PRBool val;

#define PREF_CHANGED(_P) (!pref || !strcmp(pref, _P))

  if (PREF_CHANGED(kCookiesAskPermission) &&
      NS_SUCCEEDED(prefBranch->GetBoolPref(kCookiesAskPermission, &val)))
    mCookiesAskPermission = val;

#ifndef MOZ_PHOENIX
  if (PREF_CHANGED(kCookiesDisabledForMailNews) &&
      NS_SUCCEEDED(prefBranch->GetBoolPref(kCookiesDisabledForMailNews, &val)))
    mCookiesDisabledForMailNews = val;
#endif
}

NS_IMETHODIMP
nsCookiePermission::SetAccess(nsIURI         *aURI,
                              nsCookieAccess  aAccess)
{
  //
  // NOTE: nsCookieAccess values conveniently match up with
  //       the permission codes used by nsIPermissionManager.
  //       this is nice because it avoids conversion code.
  //
  return mPermMgr->Add(aURI, kPermissionType, aAccess);
}

NS_IMETHODIMP
nsCookiePermission::CanAccess(nsIURI         *aURI,
                              nsIURI         *aFirstURI,
                              nsIChannel     *aChannel,
                              nsCookieAccess *aResult)
{
#ifndef MOZ_PHOENIX
  // disable cookies in mailnews if user's prefs say so
  if (mCookiesDisabledForMailNews) {
    //
    // try to examine the "app type" of the docshell owning this request.  if
    // we find a docshell in the heirarchy of type APP_TYPE_MAIL, then assume
    // this URI is being loaded from within mailnews.
    //
    // XXX this is a pretty ugly hack at the moment since cookies really
    // shouldn't have to talk to the docshell directly.  ultimately, we want
    // to talk to some more generic interface, which the docshell would also
    // implement.  but, the basic mechanism here of leveraging the channel's
    // (or loadgroup's) notification callbacks attribute seems ideal as it
    // avoids the problem of having to modify all places in the code which
    // kick off network requests.
    //
    PRUint32 appType = nsIDocShell::APP_TYPE_UNKNOWN;
    if (aChannel) {
      nsCOMPtr<nsIDocShellTreeItem> item, parent;
      GetInterfaceFromChannel(aChannel, NS_GET_IID(nsIDocShellTreeItem),
                              getter_AddRefs(parent));
      if (parent) {
        do {
            item = parent;
            nsCOMPtr<nsIDocShell> docshell = do_QueryInterface(item);
            if (docshell)
              docshell->GetAppType(&appType);
        } while (appType != nsIDocShell::APP_TYPE_MAIL &&
                 NS_SUCCEEDED(item->GetParent(getter_AddRefs(parent))) &&
                 parent);
      }
    }
    if ((appType == nsIDocShell::APP_TYPE_MAIL) ||
        (aFirstURI && IsFromMailNews(aFirstURI)) ||
        IsFromMailNews(aURI)) {
      *aResult = ACCESS_DENY;
      return NS_OK;
    }
  }
#endif // MOZ_PHOENIX
  
  // finally, check with permission manager...
  return mPermMgr->TestPermission(aURI, kPermissionType, (PRUint32 *) aResult);
}

NS_IMETHODIMP 
nsCookiePermission::CanSetCookie(nsIURI     *aURI,
                                 nsIChannel *aChannel,
                                 nsICookie2 *aCookie,
                                 PRBool     *aResult) 
{
  NS_ASSERTION(aURI, "null uri");

  *aResult = kDefaultPolicy;

  nsresult rv;
  PRUint32 perm;
  mPermMgr->TestPermission(aURI, kPermissionType, &perm);
  if (perm == nsIPermissionManager::DENY_ACTION) {
    *aResult = PR_FALSE;
  } else if (perm == nsIPermissionManager::ALLOW_ACTION) {
    *aResult = PR_TRUE;
  } else if (mCookiesAskPermission) {
    // check whether the user wants to be prompted. we only do this if the
    // permissionlist lookup returned UNKNOWN_ACTION (i.e., no permissionlist
    // entry exists for this host).
    NS_ASSERTION(perm == nsIPermissionManager::UNKNOWN_ACTION, "unknown permission");

    // default to rejecting, in case the prompting process fails
    *aResult = PR_FALSE;

    nsCAutoString hostPort;
    aURI->GetHostPort(hostPort);

    if (!aCookie) {
       return NS_ERROR_UNEXPECTED;
    }
    // If there is no host, use the scheme, and append "://",
    // to make sure it isn't a host or something.
    // This is done to make the dialog appear for javascript cookies from
    // file:// urls, and make the text on it not too weird. (bug 209689)
    if (hostPort.IsEmpty()) {
      aURI->GetScheme(hostPort);
      if (hostPort.IsEmpty()) {
        // still empty. Just return the default.
        return NS_OK;
      }
      hostPort = hostPort + NS_LITERAL_CSTRING("://");
    }

    // we don't cache the cookiePromptService - it's not used often, so not
    // worth the memory.
    nsCOMPtr<nsICookiePromptService> cookiePromptService =
        do_GetService(NS_COOKIEPROMPTSERVICE_CONTRACTID, &rv);
    if (NS_FAILED(rv)) return rv;

    // try to get a nsIDOMWindow from the channel...
    nsCOMPtr<nsIDOMWindow> parent;
    GetInterfaceFromChannel(aChannel, NS_GET_IID(nsIDOMWindow),
                            getter_AddRefs(parent));

    // get some useful information to present to the user:
    // whether a previous cookie already exists, and how many cookies this host
    // has set
    PRBool foundCookie;
    PRUint32 countFromHost;
    nsCOMPtr<nsICookieManager2> cookieManager = do_GetService(NS_COOKIEMANAGER_CONTRACTID, &rv);
    if (NS_SUCCEEDED(rv))
      rv = cookieManager->FindMatchingCookie(aCookie, &countFromHost, &foundCookie);
    if (NS_FAILED(rv)) return rv;

    // check if the cookie we're trying to set is already expired, and return;
    // but only if there's no previous cookie, because then we need to delete the previous
    // cookie. we need this check to avoid prompting the user for already-expired cookies.
    if (!foundCookie) {
      PRBool isSession;
      aCookie->GetIsSession(&isSession);
      if (!isSession) {
        nsInt64 currentTime = NOW_IN_SECONDS;
        PRInt64 expiry;
        aCookie->GetExpiry(&expiry);
        if (nsInt64(expiry) <= currentTime) {
          // the cookie has already expired. accept it, and let the backend figure
          // out it's expired, so that we get correct logging & notifications.
          *aResult = PR_TRUE;
          return rv;
        }
      }
    }

    PRBool rememberDecision = PR_FALSE;
    rv = cookiePromptService->CookieDialog(parent, aCookie, hostPort, 
                                           countFromHost, foundCookie,
                                           &rememberDecision, aResult);
    if (NS_FAILED(rv)) return rv;

    if (rememberDecision) {
      mPermMgr->Add(aURI, kPermissionType,
                   *aResult ? (PRUint32) nsIPermissionManager::ALLOW_ACTION
                            : (PRUint32) nsIPermissionManager::DENY_ACTION);
    }
  }

  return NS_OK;
}

NS_IMETHODIMP
nsCookiePermission::Observe(nsISupports     *aSubject,
                            const char      *aTopic,
                            const PRUnichar *aData)
{
  nsCOMPtr<nsIPrefBranch> prefBranch = do_QueryInterface(aSubject);
  if (prefBranch)
    PrefChanged(prefBranch, NS_LossyConvertUCS2toASCII(aData).get());
  return NS_OK;
}