src/node.hpp

   1 #ifndef MENUPP_NODE_HPP_
   2 #define MENUPP_NODE_HPP_
   3
   4 #include "common.hpp"
   5
   6 namespace Menu
   7 {
   8
   9     struct INode;
  10
  11     class NodeId
  12     {
  13         INode* _ptr = nullptr;
  14         int _n_child = -1;
  15
  16     public:
  17         NodeId() {}
  18         NodeId(INode* ptr, size_t n_child)
  19         : _ptr(ptr), _n_child(static_cast<int>(n_child))
  20         {}
  21
  22         static const NodeId ROOT;
  23
  24         bool is_valid() const { return _n_child >= 0; }
  25
  26         bool is_root() const { return is_valid() && !_ptr; }
  27
  28         INode* addr() const { return _ptr; }
  29
  30         int n() const { return _n_child; }
  31
  32         NodeId parent() const;
  33
  34         INode* get(INode& root);
  35
  36         friend std::ostream& operator<<(std::ostream& os, const NodeId& nid)
  37         { return os << '(' << nid._ptr << ", " << nid._n_child << ')'; }
  38
  39         friend bool operator==(const NodeId& x, const NodeId& y)
  40         { return x._ptr == y._ptr && x._n_child == y._n_child; }
  41
  42         friend bool operator!=(const NodeId& x, const NodeId& y)
  43         { return !(x == y); }
  44     };
  45
  46     const NodeId NodeId::ROOT { nullptr, 0 };
  47
  48     struct INode
  49     {
  50         virtual ~INode() = default;
  51         virtual void set_id(NodeId id) = 0;
  52         virtual NodeId id() const = 0;
  53         virtual void dump(std::ostream& os, size_t indent = 4, size_t total_indent = 0) const = 0;
  54         virtual NodeId move(Move m) = 0;
  55         virtual INode* get(size_t n) = 0;
  56         virtual const char* label() const = 0;
  57
  58         friend std::ostream& operator<<(std::ostream& os, const INode& node);
  59     };
  60
  61     NodeId NodeId::parent() const
  62     {
  63         return (_ptr
  64             ? _ptr->id()
  65             : (is_valid()
  66                 ? (is_root() ? NodeId() : ROOT)
  67                 : NodeId()));
  68     }
  69
  70     INode* NodeId::get(INode& root)
  71     {
  72         return is_valid()
  73             ? (is_root()
  74                 ? &root
  75                 : _ptr->get(static_cast<size_t>(_n_child)))
  76             : nullptr;
  77     }
  78
  79     std::ostream& operator<<(std::ostream& os, const INode& node)
  80     { node.dump(os, 4); return os; }
  81
  82 }
  83
  84 #endif // MENUPP_NODE_HPP_