// Copyright 2022 The Dawn Authors
//
// Licensed 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.

#include "dawn/native/PipelineCache.h"

namespace dawn::native {

PipelineCacheBase::PipelineCacheBase(BlobCache* cache, const CacheKey& key)
    : mCache(cache), mKey(key) {}

Blob PipelineCacheBase::Initialize() {
    ASSERT(!mInitialized);
    Blob blob = mCache != nullptr ? mCache->Load(mKey) : Blob();
    mCacheHit = !blob.Empty();
    mInitialized = true;
    return blob;
}

bool PipelineCacheBase::CacheHit() const {
    ASSERT(mInitialized);
    return mCacheHit;
}

MaybeError PipelineCacheBase::Flush() {
    if (mCache == nullptr) {
        return {};
    }
    // Try to write the data out to the persistent cache.
    Blob blob;
    DAWN_TRY(SerializeToBlobImpl(&blob));
    if (blob.Size() > 0) {
        // Using a simple heuristic to decide whether to write out the blob right now. May need
        // smarter tracking when we are dealing with monolithic caches.
        mCache->Store(mKey, blob);
    }
    return {};
}

MaybeError PipelineCacheBase::FlushIfNeeded() {
    ASSERT(mInitialized);
    if (!CacheHit()) {
        return Flush();
    }
    return {};
}

}  // namespace dawn::native