// Copyright {Jagger Software Limited} 2003

#ifndef CONTAINER_LINE_VIEW_INCLUDED
#define CONTAINER_LINE_VIEW_INCLUDED

#include "container/range_view.hpp"
#include <cstddef>
#include <vector>

namespace container
{
    template<typename iterator>
    class line_view // <<concrete>>
    {
    public: // 'tors
 
        line_view(iterator, iterator);
        // compiler generated copy c'tor ok
        // compiler generated non virtual d'tor ok

    public: // limits

        iterator begin() const;
        iterator end() const;

    public: // iterator --> line/row/col
    
        range_view<iterator> to_line(iterator) const; // [begin(), end())

        size_t   line_number(iterator) const;
        size_t column_number(iterator) const;

    public: // line# --> line

        size_t last_line_number() const;
   
        range_view<iterator> operator[](size_t) const; // [1, last_line_number()]

    private: // implementation

        size_t    distance_to(iterator) const;
        
        size_t       iterator_to_line_number(iterator) const;
        iterator  line_number_to_line_start(size_t) const;

    private: // validation 

        void range_check(size_t) const;

    private: // inappropriate

        line_view & operator=(const line_view &);

    private: // state

        const range_view<iterator> source;
        ::std::vector<size_t> line_starts;

    };
    
    // convenience
    
    template<typename iterator>
    line_view<iterator> make_line_view(iterator, iterator);
}

#include "container/line_view-template.hpp"

#endif