gecko-dev/extensions/xforms/nsXFormsUtilityService.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** 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 Mozilla XForms support.
 *
 * The Initial Developer of the Original Code is
 * IBM Corporation.
 * Portions created by the Initial Developer are Copyright (C) 2004
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *  Aaron Reed <aaronr@us.ibm.com>
 *
 * 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
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 * the provisions above, a recipient may use your version of this file under
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 *
 * ***** END LICENSE BLOCK ***** */

#include "nsIServiceManager.h"
#include "nsXFormsUtilityService.h"
#include "nsXFormsUtils.h"
#include "nsIXTFElement.h"
#include "nsIDOMNode.h"
#include "nsIDOMElement.h"
#include "nsString.h"
#include "nsIDOMDocument.h"
#include "nsIXFormsModelElement.h"
#include "nsIDOMNodeList.h"
#include "nsIInstanceElementPrivate.h"
#include "nsIXFormsRepeatElement.h"
#include "nsISchemaValidator.h"
#include "nsISchemaDuration.h"
#include "nsXFormsSchemaValidator.h"
#include "prdtoa.h"

NS_IMPL_ISUPPORTS1(nsXFormsUtilityService, nsIXFormsUtilityService)

/* I don't know why Doron didn't put this in the .idl so that it could be added
 * to the generated .h file.  Put it here for now
 */
#define NS_SCHEMAVALIDATOR_CONTRACTID  "@mozilla.org/schemavalidator;1"


NS_IMETHODIMP
nsXFormsUtilityService::GetModelFromNode(nsIDOMNode *aNode, 
                                         nsIDOMNode **aModel)
{
  nsCOMPtr<nsIDOMElement> element = do_QueryInterface(aNode);
  NS_ASSERTION(aModel, "no return buffer, we'll crash soon");
  *aModel = nsnull;

  nsAutoString namespaceURI;
  aNode->GetNamespaceURI(namespaceURI);

  // If the node is in the XForms namespace and XTF based, then it should
  //   be able to be handled by GetModel.  Otherwise it is probably an instance
  //   node in a instance document.
  if (!namespaceURI.EqualsLiteral(NS_NAMESPACE_XFORMS)) {
    return NS_ERROR_FAILURE;
  }

  nsCOMPtr<nsIModelElementPrivate> modelPriv = nsXFormsUtils::GetModel(element);
  nsCOMPtr<nsIDOMNode> modelElement = do_QueryInterface(modelPriv);
  if( modelElement ) {
    NS_IF_ADDREF(*aModel = modelElement);
  }

  // No model found
  NS_ENSURE_TRUE(*aModel, NS_ERROR_FAILURE);

  return NS_OK;
}


/**
 * Function to see if the given node is associated with the given model.
 * Right now this function is only called by XPath in the case of the
 * instance() function.
 * The provided node can be an instance node from an instance
 * document and thus be associated to the model in that way (model elements
 * contain instance elements).  Otherwise the node will be an XForms element
 * that was used as the context node of the XPath expression (i.e the
 * XForms control has an attribute that contains an XPath expression).
 * Form controls are associated with model elements either explicitly through
 * single-node binding or implicitly (if model cannot by calculated, it
 * will use the first model element encountered in the document).  The model
 * can also be inherited from a containing element like xforms:group or
 * xforms:repeat.
 */
NS_IMETHODIMP
nsXFormsUtilityService::IsNodeAssocWithModel( nsIDOMNode *aNode, 
                                              nsIDOMNode *aModel,
                                              PRBool     *aModelAssocWithNode)
{

  nsCOMPtr<nsIDOMNode> modelNode;

  nsAutoString namespaceURI;
  aNode->GetNamespaceURI(namespaceURI);
  // If the node is in the XForms namespace and XTF based, then it should
  //   be able to be handled by GetModel.  Otherwise it is probably an instance
  //   node in a instance document.
  if (namespaceURI.EqualsLiteral(NS_NAMESPACE_XFORMS)) {
    nsCOMPtr<nsIDOMElement> element = do_QueryInterface(aNode);
    nsCOMPtr<nsIModelElementPrivate> modelPriv = nsXFormsUtils::GetModel(element);
    modelNode = do_QueryInterface(modelPriv);
  } else { 
    // We are assuming that if the node coming in isn't a proper XForms element,
    //   then it is an instance element in an instance doc.  Now we just have
    //   to determine if the given model contains this instance document.
    nsCOMPtr<nsIDOMNode> instNode;
    nsresult rv =
      nsXFormsUtils::GetInstanceNodeForData(aNode, getter_AddRefs(instNode));
    if (NS_SUCCEEDED(rv) && instNode) {
      instNode->GetParentNode(getter_AddRefs(modelNode));
    }
  }

  if (modelNode && (modelNode == aModel)) {
    *aModelAssocWithNode = PR_TRUE;
  } else {
    *aModelAssocWithNode = PR_FALSE;
  }

  return NS_OK;
}

NS_IMETHODIMP
nsXFormsUtilityService::GetInstanceDocumentRoot(const      nsAString& aID,
                                                nsIDOMNode *aModelNode,
                                                nsIDOMNode **aInstanceRoot)
{
  nsresult rv = NS_ERROR_FAILURE;
  NS_ASSERTION(aInstanceRoot, "no return buffer, we'll crash soon");
  *aInstanceRoot = nsnull;

  if (aID.IsEmpty()) {
    return rv;
  }

  nsCOMPtr<nsIXFormsModelElement> modelElement = do_QueryInterface(aModelNode);
  nsCOMPtr<nsIDOMDocument> doc;
  rv = modelElement->GetInstanceDocument(aID, getter_AddRefs(doc));
  NS_ENSURE_SUCCESS(rv, rv);
  
  nsCOMPtr<nsIDOMElement> element;
  rv = doc->GetDocumentElement(getter_AddRefs(element));
  NS_ENSURE_SUCCESS(rv, rv);

  if (element) {
    NS_IF_ADDREF(*aInstanceRoot = element);
  }

  return rv;
}

/* Gotta do this via the service since we don't want transformiix to require
 * any of the new extensions, like schema-validation
 */
NS_IMETHODIMP 
nsXFormsUtilityService::ValidateString(const nsAString & aValue, 
                                       const nsAString & aType, 
                                       const nsAString & aNamespace,
                                       PRBool *aResult)
{

  NS_ASSERTION(aResult, "no return buffer for result so we'll crash soon");
  *aResult = PR_FALSE;

  nsXFormsSchemaValidator *validator = new nsXFormsSchemaValidator();
  if (validator) {
    *aResult = validator->ValidateString(aValue, aType, aNamespace);
    delete validator;
  }
  return *aResult ? NS_OK : NS_ERROR_FAILURE;
}

NS_IMETHODIMP
nsXFormsUtilityService::GetRepeatIndex(nsIDOMNode *aRepeat, PRInt32 *aIndex)
{
  NS_ASSERTION(aIndex, "no return buffer for index, we'll crash soon");
  *aIndex = 0;

  nsCOMPtr<nsIXFormsRepeatElement> repeatEle = do_QueryInterface(aRepeat);
  if (!repeatEle) {
    // if aRepeat isn't a repeat element, then setting aIndex to -1 to tell
    // XPath to return NaN.  Per 7.8.5 in the spec (1.0, 2nd edition)
    *aIndex = -1;
  } else {
    PRUint32 retIndex = 0;
    nsresult rv = repeatEle->GetIndex(&retIndex);
    NS_ENSURE_SUCCESS(rv, rv);
    *aIndex = retIndex;
  }

  return NS_OK;
}

NS_IMETHODIMP
nsXFormsUtilityService::GetMonths(const nsAString & aValue, 
                                  PRInt32         * aMonths)
{
  NS_ASSERTION(aMonths, "no return buffer for months, we'll crash soon");

  *aMonths = 0;
  nsCOMPtr<nsISchemaDuration> duration;
  nsCOMPtr<nsISchemaValidator> schemaValidator = 
    do_CreateInstance(NS_SCHEMAVALIDATOR_CONTRACTID);
  NS_ENSURE_TRUE(schemaValidator, NS_ERROR_FAILURE);

  nsresult rv = schemaValidator->ValidateBuiltinTypeDuration(aValue, 
                                                    getter_AddRefs(duration));
  NS_ENSURE_SUCCESS(rv, rv);

  PRInt32 sumMonths;
  PRUint32 years;
  PRUint32 months;

  duration->GetYears(&years);
  duration->GetMonths(&months);

  sumMonths = months + years*12;
  PRBool negative;
  duration->GetNegative(&negative);
  if (negative) {
    // according to the spec, "the sign of the result will match the sign
    // of the duration"
    sumMonths *= -1;
  }
  
  *aMonths = sumMonths;

  return NS_OK;
}

NS_IMETHODIMP
nsXFormsUtilityService::GetSeconds(const nsAString & aValue, 
                                   double          * aSeconds)
{
  nsCOMPtr<nsISchemaDuration> duration;
  nsCOMPtr<nsISchemaValidator> schemaValidator = 
    do_CreateInstance(NS_SCHEMAVALIDATOR_CONTRACTID);
  NS_ENSURE_TRUE(schemaValidator, NS_ERROR_FAILURE);

  nsresult rv = schemaValidator->ValidateBuiltinTypeDuration(aValue, 
                                                    getter_AddRefs(duration));
  NS_ENSURE_SUCCESS(rv, rv);
  double sumSeconds;
  PRUint32 days;
  PRUint32 hours;
  PRUint32 minutes;
  PRUint32 seconds;
  double fractSecs;

  duration->GetDays(&days);
  duration->GetHours(&hours);
  duration->GetMinutes(&minutes);
  duration->GetSeconds(&seconds);
  duration->GetFractionSeconds(&fractSecs);

  sumSeconds = seconds + minutes*60 + hours*3600 + days*24*3600 + fractSecs;

  PRBool negative;
  duration->GetNegative(&negative);
  if (negative) {
    // according to the spec, "the sign of the result will match the sign
    // of the duration"
    sumSeconds *= -1;
  }

  *aSeconds = sumSeconds;
  return NS_OK;
}

NS_IMETHODIMP
nsXFormsUtilityService::GetSecondsFromDateTime(const nsAString & aValue, 
                                               double          * aSeconds)
{
  PRTime dateTime;
  nsCOMPtr<nsISchemaValidator> schemaValidator = 
    do_CreateInstance(NS_SCHEMAVALIDATOR_CONTRACTID);
  NS_ENSURE_TRUE(schemaValidator, NS_ERROR_FAILURE);

  nsresult rv = schemaValidator->ValidateBuiltinTypeDateTime(aValue, &dateTime); 
  NS_ENSURE_SUCCESS(rv, rv);
                                               
  PRTime secs64 = dateTime, remain64;
  PRInt64 usecPerSec;
  PRInt32 secs32, remain32;

  // convert from PRTime (microseconds from epoch) to seconds.
  LL_I2L(usecPerSec, PR_USEC_PER_SEC);
  LL_MOD(remain64, secs64, usecPerSec);   /* remainder after conversion */
  LL_DIV(secs64, secs64, usecPerSec);     /* Conversion in whole seconds */

  // convert whole seconds and remainder to PRInt32
  LL_L2I(secs32, secs64);
  LL_L2I(remain32, remain64);

  // ready the result to send back to transformiix land now in case there are
  // no fractional seconds or we end up having a problem parsing them out.  If
  // we do, we'll just ignore the fractional seconds.
  double totalSeconds = secs32;
  *aSeconds = totalSeconds;

  // We're not getting fractional seconds back in the PRTime we get from
  // the schemaValidator.  We'll have to figure out the fractions from
  // the original value.  Since ValidateBuiltinTypeDateTime returned
  // successful for us to get this far, we know that the value is in
  // the proper format.
  int findFractionalSeconds = aValue.FindChar('.');
  if (findFractionalSeconds < 0) {
    // no fractions of seconds, so we are good to go as we are
    return NS_OK;
  }

  const nsAString& fraction = Substring(aValue, findFractionalSeconds+1, 
                                        aValue.Length());

  PRBool done = PR_FALSE;
  PRUnichar currentChar;
  nsCAutoString fractionResult;
  nsAString::const_iterator start, end, buffStart;
  fraction.BeginReading(start);
  fraction.BeginReading(buffStart);
  fraction.EndReading(end);

  while ((start != end) && !done) {
    currentChar = *start++;

    // Time is usually terminated with Z or followed by a time zone
    // (i.e. -05:00).  Time can also be terminated by the end of the string, so
    // test for that as well.  All of this specified at:
    // http://www.w3.org/TR/xmlschema-2/#dateTime
    if ((currentChar == 'Z') || (currentChar == '+') || (currentChar == '-') ||
        (start == end)) {
      fractionResult.AssignLiteral("0.");
      AppendUTF16toUTF8(Substring(buffStart.get(), start.get()-1), 
                        fractionResult);
    } else if ((currentChar > '9') || (currentChar < '0')) {
      // has to be a numerical character or else abort.  This should have been
      // caught by the schemavalidator, but it is worth double checking.
      done = PR_TRUE;
    }
  }

  if (fractionResult.IsEmpty()) {
    // couldn't successfully parse the fractional seconds, so we'll just return
    // without them.
    return NS_OK;
  }

  // convert the result string that we have to a double and add it to the total
  totalSeconds += PR_strtod(fractionResult.get(), nsnull);
  *aSeconds = totalSeconds;

  return NS_OK;
}

NS_IMETHODIMP
nsXFormsUtilityService::GetDaysFromDateTime(const nsAString & aValue, 
                                            PRInt32         * aDays)
{
  NS_ASSERTION(aDays, "no return buffer for days, we'll crash soon");
  *aDays = 0;

  PRTime date;
  nsCOMPtr<nsISchemaValidator> schemaValidator = 
    do_CreateInstance(NS_SCHEMAVALIDATOR_CONTRACTID);
  NS_ENSURE_TRUE(schemaValidator, NS_ERROR_FAILURE);

  // aValue could be a xsd:date or a xsd:dateTime.  If it is a dateTime, we
  // should ignore the hours, minutes, and seconds according to 7.10.2 in
  // the spec.  So search for such things now.  If they are there, strip 'em.
  int findTime = aValue.FindChar('T');

  nsAutoString dateString;
  dateString.Assign(aValue);
  if (findTime >= 0) {
    dateString.Assign(Substring(dateString, 0, findTime));
  }

  nsresult rv = schemaValidator->ValidateBuiltinTypeDate(dateString, &date); 
  NS_ENSURE_SUCCESS(rv, rv);

  PRTime secs64 = date;
  PRInt64 usecPerSec;
  PRInt32 secs32;

  // convert from PRTime (microseconds from epoch) to seconds.  Shouldn't
  // have to worry about remainders since input is a date.  Smallest value
  // is in whole days.
  LL_I2L(usecPerSec, PR_USEC_PER_SEC);
  LL_DIV(secs64, secs64, usecPerSec);

  // convert whole seconds to PRInt32
  LL_L2I(secs32, secs64);

  // convert whole seconds to days.  86400 seconds in a day.
  *aDays = secs32/86400;

  return NS_OK;
}