/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

// Helper functions for the templated functionality in property_cache_util.h

#include "net/instaweb/rewriter/public/property_cache_util.h"

#include "net/instaweb/util/public/property_cache.h"
#include "pagespeed/kernel/base/proto_util.h"

namespace net_instaweb {

const PropertyValue* DecodeFromPropertyCacheHelper(
    const PropertyCache* cache,
    AbstractPropertyPage* page,
    const PropertyCache::Cohort* cohort,
    StringPiece property_name,
    int64 cache_ttl_ms,
    PropertyCacheDecodeResult* status) {
  if (cohort == NULL || page == NULL) {
    *status = kPropertyCacheDecodeNotFound;
    return NULL;
  }

  PropertyValue* property_value = page->GetProperty(cohort, property_name);
  if (property_value == NULL || !property_value->has_value()) {
    *status = kPropertyCacheDecodeNotFound;
    return NULL;
  }

  if ((cache_ttl_ms != -1) && cache->IsExpired(property_value, cache_ttl_ms)) {
    *status = kPropertyCacheDecodeExpired;
    return NULL;
  }
  return property_value;
}

PropertyCacheUpdateResult UpdateInPropertyCache(
    const protobuf::MessageLite& value,
    const PropertyCache::Cohort* cohort,
    StringPiece property_name,
    bool write_cohort,
    AbstractPropertyPage* page) {
  if (cohort == NULL || page == NULL) {
    return kPropertyCacheUpdateNotFound;
  }

  GoogleString buf;
  if (!value.SerializeToString(&buf)) {
    return kPropertyCacheUpdateEncodeError;
  }

  page->UpdateValue(cohort, property_name, buf);

  if (write_cohort) {
    page->WriteCohort(cohort);
  }

  return kPropertyCacheUpdateOk;
}

}  // namespace net_instaweb
