/*
 * ExtLib
 * Copyright 2024 Dominick Allen
 *
 * 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 "memory.hpp"

#include <cstdint>

namespace fud {

FudStatus copyMem(void* destination, size_t destination_size, const void* source, size_t count)
{
    if (anyAreNull(destination, source)) {
        return FudStatus::NullPointer;
    }

    if (destination_size < count) {
        return FudStatus::InvalidInput;
    }

    auto* destPtr = static_cast<uint8_t*>(destination);
    const auto* sourcePtr = static_cast<const uint8_t*>(source);
    for (decltype(destination_size) idx = 0; idx < count; ++idx) {
        destPtr[idx] = sourcePtr[idx];
    }

    return FudStatus::Success;
}

FudStatus compareMem(const void* lhs, size_t destination_size, const void* rhs, size_t count, int* difference)
{
    if (anyAreNull(lhs, rhs, difference)) {
        return FudStatus::NullPointer;
    }

    if (destination_size < count) {
        return FudStatus::InvalidInput;
    }

    int localDifference = 0;
    // NOLINTBEGIN(readability-magic-numbers)
    for (decltype(destination_size) idx = 0; idx < count; idx++) {
        localDifference = static_cast<const uint8_t*>(lhs)[idx] - static_cast<const uint8_t*>(rhs)[idx];
        if (localDifference != 0) {
            *difference = localDifference;
            return FudStatus::Success;
        }
    }
    *difference = localDifference;

    return FudStatus::Success;
}

Result<int, FudStatus> compareMem(const void* lhs, size_t destination_size, const void* rhs, size_t count)
{
    int difference = 0;
    auto status = compareMem(lhs, destination_size, rhs, count, &difference);
    if (status != FudStatus::Success)
    {
        return Result<int, FudStatus>::error(status);
    }

    return Result<int, FudStatus>::okay(difference);
}

FudStatus setMemory(void* data, size_t dataSize, uint8_t pattern, size_t count)
{
    if (data == nullptr)
    {
        return FudStatus::NullPointer;
    }

    if (count > dataSize)
    {
        return FudStatus::InvalidInput;
    }

    for (size_t idx = 0; idx < count; ++idx)
    {
        static_cast<uint8_t*>(data)[idx] = pattern;
    }

    return FudStatus::Success;
}

FudStatus setMemory(
    void* data,
    size_t collectionCount,
    size_t eltOffset,
    size_t eltSize,
    uint8_t pattern,
    size_t eltCount)
{
    if (eltOffset >= collectionCount)
    {
        return FudStatus::InvalidInput;
    }

    if (eltOffset + eltCount > collectionCount)
    {
        return FudStatus::InvalidInput;
    }

    auto dataSize = collectionCount * eltSize;
    auto byteOffset = eltOffset * eltSize;
    auto byteCount = eltCount * eltSize;

    auto remainingSize = dataSize - byteOffset;

    auto* offsetData = static_cast<uint8_t*>(data) + byteOffset;
    return setMemory(offsetData, remainingSize, pattern, byteCount);
}

} // namespace fud