// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <stdio.h>
#include <unistd.h>

#include <blobfs/compression/blob-compressor.h>
#include <blobfs/compression/lz4.h>
#include <blobfs/compression/zstd.h>
#include <fbl/algorithm.h>
#include <fbl/auto_call.h>
#include <fbl/macros.h>
#include <fbl/unique_ptr.h>
#include <fs/trace.h>
#include <zircon/types.h>

namespace blobfs {

std::optional<BlobCompressor> BlobCompressor::Create(CompressionAlgorithm algorithm,
                                                     size_t blob_size) {
    switch (algorithm) {
    case CompressionAlgorithm::LZ4: {
        fzl::OwnedVmoMapper compressed_blob;
        size_t max = LZ4Compressor::BufferMax(blob_size);
        zx_status_t status = compressed_blob.CreateAndMap(max, "lz4-blob");
        if (status != ZX_OK) {
            return std::nullopt;
        }
        fbl::unique_ptr<LZ4Compressor> compressor;
        status = LZ4Compressor::Create(blob_size, compressed_blob.start(),
                                       compressed_blob.size(), &compressor);
        if (status != ZX_OK) {
            return std::nullopt;
        }
        auto result = BlobCompressor(std::move(compressor), std::move(compressed_blob));
        return std::make_optional(std::move(result));
    }
    case CompressionAlgorithm::ZSTD: {
        fzl::OwnedVmoMapper compressed_blob;
        size_t max = ZSTDCompressor::BufferMax(blob_size);
        zx_status_t status = compressed_blob.CreateAndMap(max, "zstd-blob");
        if (status != ZX_OK) {
            return std::nullopt;
        }
        fbl::unique_ptr<ZSTDCompressor> compressor;
        status = ZSTDCompressor::Create(blob_size, compressed_blob.start(),
                                        compressed_blob.size(), &compressor);
        if (status != ZX_OK) {
            return std::nullopt;
        }
        auto result = BlobCompressor(std::move(compressor), std::move(compressed_blob));
        return std::make_optional(std::move(result));
    }
    default:
        return std::nullopt;
    }
}

BlobCompressor::BlobCompressor(fbl::unique_ptr<Compressor> compressor,
                               fzl::OwnedVmoMapper compressed_blob)
    : compressor_(std::move(compressor)), compressed_blob_(std::move(compressed_blob)) {}

BlobCompressor::~BlobCompressor() = default;

} // namespace blobfs