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#pragma once

#include <utils/smallstringview.h>

namespace Sqlite {

constexpr int compare(Utils::SmallStringView first, Utils::SmallStringView second) noexcept
{
    auto difference = std::char_traits<char>::compare(first.data(),
                                                      second.data(),
                                                      std::min(first.size(), second.size()));

    if (difference == 0)
        return int(first.size() - second.size());

    return difference;
}

template<typename SqliteRange,
         typename Range,
         typename CompareKey,
         typename InsertCallback,
         typename UpdateCallback,
         typename DeleteCallback>
void insertUpdateDelete(SqliteRange &&sqliteRange,
                        Range &&values,
                        CompareKey compareKey,
                        InsertCallback insertCallback,
                        UpdateCallback updateCallback,
                        DeleteCallback deleteCallback)
{
    auto currentSqliteIterator = sqliteRange.begin();
    auto endSqliteIterator = sqliteRange.end();
    auto currentValueIterator = values.begin();
    auto endValueIterator = values.end();

    while (true) {
        bool hasMoreValues = currentValueIterator != endValueIterator;
        bool hasMoreSqliteValues = currentSqliteIterator != endSqliteIterator;
        if (hasMoreValues && hasMoreSqliteValues) {
            auto &&sqliteValue = *currentSqliteIterator;
            auto &&value = *currentValueIterator;
            auto compare = compareKey(sqliteValue, value);
            if (compare == 0) {
                updateCallback(sqliteValue, value);
                ++currentValueIterator;
                ++currentSqliteIterator;
            } else if (compare > 0) {
                insertCallback(value);
                ++currentValueIterator;
            } else if (compare < 0) {
                deleteCallback(sqliteValue);
                ++currentSqliteIterator;
            }
        } else if (hasMoreValues) {
            insertCallback(*currentValueIterator);
            ++currentValueIterator;
        } else if (hasMoreSqliteValues) {
            deleteCallback(*currentSqliteIterator);
            ++currentSqliteIterator;
        } else {
            break;
        }
    }
}

} // namespace Sqlite
