/*------------------------------------------------------------------------------
 *	Copyright (c) 2023 by Bai Bing (seread@163.com)
 *	S++ COPYING file for copying and redistribution conditions.
 *
 *  Alians IT Studio.
 *----------------------------------------------------------------------------*/

#pragma once

#include <algorithm>
#include <iostream>
#include <string>

#include "_Define.h"

namespace ais
{
    //================================================================================
    /// A Class for slicing
    class AIS_EXPORT Slice
    {
    public:
        //====================================Attributes==============================
        size_t start{0};
        size_t stop{1};
        size_t step{1};

        //============================================================================
        /// Constructor
        ///
        constexpr Slice() = default;

        //============================================================================
        /// Constructor
        ///
        /// @param stop (index not included)
        ///
        constexpr explicit Slice(size_t stop) noexcept : stop(stop) {}

        //============================================================================
        /// Constructor
        ///
        /// @param start
        /// @param stop (index not included)
        ///
        constexpr Slice(size_t start, size_t stop) noexcept : start(start), stop(stop) {}

        //============================================================================
        /// Constructor
        ///
        /// @param start
        /// @param stop (not included)
        /// @param step
        ///
        constexpr Slice(size_t start, size_t stop, size_t step) noexcept : start(start), stop(stop), step(step) {}

        //============================================================================
        /// Equality operator
        ///
        /// @param otherSlice
        ///
        /// @return bool
        ///
        bool operator==(const Slice &otherSlice) const noexcept;

        //============================================================================
        /// Not equality operator
        ///
        /// @param otherSlice
        ///
        /// @return bool
        ///
        bool operator!=(const Slice &otherSlice) const noexcept;

        //============================================================================
        /// Prints the shape to the console
        ///
        /// @return std::string
        ///
        std::string str() const;

        //============================================================================
        /// Prints the shape to the console
        ///
        void print() const;

        //============================================================================
        /// Make the slice all positive and does some error checking
        ///
        /// @param arraySize
        ///
        void make_positive_and_validate(size_t arraySize);

        //============================================================================
        /// Returns the number of elements that the slice contains.
        /// be aware that this method will also make the slice all
        /// positive!
        ///
        /// @param arraySize
        ///
        size_t element_number(size_t arraySize);

        //============================================================================
        /// IO operator for the Slice class
        ///
        /// @param stream
        /// @param slice
        ///
        /// @return std::ostream
        ///
        friend std::ostream &operator<<(std::ostream &stream, const Slice &slice)
        {
            stream << slice.str();
            return stream;
        }
    };
} // namespace ais