File indexing completed on 2022-11-29 12:54:59

0001 /*
0002     SPDX-FileCopyrightText: 2003-2006 Cies Breijs <cies AT kde DOT nl>
0003 
0004     SPDX-License-Identifier: GPL-2.0-or-later
0005 */
0006 
0007 #ifndef _TREENODE_H_
0008 #define _TREENODE_H_
0009 
0010 #include <QList>
0011 
0012 
0013 #include "token.h"
0014 #include "value.h"
0015 
0016 
0017 
0018 /**
0019  * @short A node in the pointer based node tree structure.
0020  *
0021  * The TreeNode object is a node in the node tree as created by the Parser.
0022  * It can be executed by the Executer.
0023  *
0024  * The list of pointers to the children of the TreeNode is only created
0025  * when it is needed.
0026  * Each TreeNode has a list of pointers to its children, a pointer to its
0027  * parent, a pointer to one Token, and can also have a pointer to a Value.
0028  *
0029  * @author Cies Breijs
0030  */
0031 class TreeNode
0032 {
0033     public:
0034         /**
0035          * @short Constructor.
0036          * Initialses the TreeNode.
0037          * @param token pointer to Token that the TreeNode is associated with.
0038          */
0039         explicit TreeNode(Token* token)                  { init(nullptr, token); }
0040 
0041         /**
0042          * @short Destructor.
0043          * This deletes the Value and the Token associated with this TreeNode.
0044          * The childList auto-deletes all the children, which means that deleting
0045          * the root node deletes the whole tree.
0046          */
0047         virtual ~TreeNode();
0048 
0049 
0050 
0051         /** @returns the pointer to the parent TreeNode. @see setParent() */
0052         TreeNode* parent()                      { return _parent; }
0053 
0054         /** @returns the pointer to associated Token. @see setToken() */
0055         Token*    token()                       { return _token; }
0056 
0057         /** @returns the pointer to associated Value. @see setValue() @see setNullValue() */
0058         Value*    value()                       { if (_value == nullptr) _value = new Value(); return _value; }
0059 
0060 
0061 
0062         /** Sets the pointer to the parent to @p parent. @see parent() */
0063         void      setParent(TreeNode* parent)   { _parent = parent; }
0064 
0065         /** Sets the pointer to the associated token to @p token. @see token() and @see TreeNode() */
0066         void      setToken(Token* token)        { _token = token; }
0067 
0068         /** Sets the pointer to the associated value to @p value. @see setNullValue() @see value() */
0069         void      setValue(Value value)         { delete _value; _value = new Value(value); }
0070 
0071         /** Sets the pointer to the associated value to zero. @see setValue() @see value() */
0072         void      setNullValue()                {  delete _value; _value = nullptr;  } // appears Empty (see value())
0073 
0074 
0075 
0076         /** @returns TRUE is the TreeNode has an associated Value. @see value @see setValue */
0077         bool      hasValue() const              { return _value != nullptr; }
0078 
0079         /** @returns TRUE is the TreeNode has children. @see childCount @see appendChild */
0080         bool      hasChildren() const           { if (childList == nullptr) return false; else return !childList->isEmpty(); }
0081 
0082         /** @returns the amount of children. @see appendChild @see hasChildren */
0083         uint      childCount() const            { if (childList == nullptr) return 0; else return childList->size(); }
0084 
0085         /**
0086          * Appends the pointer to the TreeNode @p newChild to the childList and
0087          * sets the child's parent to this. @see childCount @see hasChildren
0088          */
0089         void      appendChild(TreeNode* newChild);
0090 
0091 
0092 
0093         /** @returns the pointer to child number @p i (zero if the child does not exists). This does not change the current child. */
0094         TreeNode* child(int i);
0095 
0096         /** @returns the pointer to the first child (zero if the child does not exists), and set the current child to the first */
0097         TreeNode* firstChild();
0098 
0099         /** @returns the pointer to the next child (zero if the child does not exists), and set the current child to the next */
0100         TreeNode* nextChild();
0101 
0102 
0103         /** @returns the pointer to the next sibling; the next child of the parent (zero if the next sibling does not exists) */
0104         TreeNode* nextSibling();
0105 
0106 
0107         /** @returns the node tree, starting from 'this' node, as a multi line string */
0108         QString toString();
0109 
0110 
0111 
0112     private:
0113         /// Initializes a the TreeNode. Called by the constructor.
0114         void init(TreeNode* parent, Token* token);
0115 
0116         /** Calls itself, @ref show(), and @ref showTree() for each of the children */
0117         virtual void show(QString& str, int indent = 0) const;
0118 
0119         /** Prints an indented string describing itself to de debug info */
0120         void showTree(QString& str, int indent = 0);
0121 
0122         int findChildIndex(TreeNode* child);
0123     
0124         /// typedef for the ChildList.
0125         typedef QList<TreeNode*>         ChildList;
0126 
0127         /// The childList, contains pointers to the children of this node.
0128         ChildList                       *childList;
0129 
0130         /// Keeps track of the index of the current child. Zero when no child list is available.
0131         int                              currentChildIndex;
0132 
0133 
0134 
0135         /// The pointer to the parent of this TreeNode.
0136         TreeNode                        *_parent;
0137 
0138         /// The pointer to the token associated with this TreeNode (cannot be zero).
0139         Token                           *_token;
0140 
0141         /// The pointer to the value associated with this TreeNode (can be zero).
0142         Value                           *_value;
0143 };
0144 
0145 #endif  // _TREENODE_H_