include/paimon/utils/range.h

/*
 * 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.
 */

#pragma once
#include <optional>
#include <string>
#include <vector>

#include "paimon/visibility.h"

namespace paimon {
/// Range represents from (inclusive) and to (inclusive).
struct PAIMON_EXPORT Range {
    Range(int64_t _from, int64_t _to);

    /// Returns the number of integers in the range [from, to].
    int64_t Count() const;

    /// Computes the intersection of two ranges.
    static std::optional<Range> Intersection(const Range& left, const Range& right);

    /// Checks whether two ranges have any overlap.
    static bool HasIntersection(const Range& left, const Range& right);

    /// Sorts a list of ranges by `from`, then merges overlapping or adjacent ranges.
    /// @param ranges Input vector of ranges to merge.
    /// @param adjacent If true, also merges ranges that are adjacent (e.g., [1,3] and [4,5] →
    /// [1,5]).
    ///                 If false, only merges strictly overlapping ranges.
    /// @return A new vector of non-overlapping, sorted ranges.
    static std::vector<Range> SortAndMergeOverlap(const std::vector<Range>& ranges, bool adjacent);

    /// Computes the set intersection of two collections of disjoint, sorted ranges.
    static std::vector<Range> And(const std::vector<Range>& left, const std::vector<Range>& right);

    /// Excludes the given ranges from this range and returns the remaining ranges.
    ///
    /// For example, if this range is [0, 10000] and ranges to exclude are [1000, 2000], [3000,
    /// 4000], [5000, 6000], then the result is [0, 999], [2001, 2999], [4001, 4999], [6001, 10000].
    ///
    /// @param ranges The ranges to exclude (can be unsorted and overlapping).
    /// @return The remaining ranges after exclusion.
    std::vector<Range> Exclude(const std::vector<Range>& ranges) const;

    bool operator==(const Range& other) const;
    bool operator<(const Range& other) const;

    std::string ToString() const;

    int64_t from;
    int64_t to;
};

}  // namespace paimon