#ifndef DEFINITIONNODE_H
#define DEFINITIONNODE_H

#include "definition_global.h"

namespace paysages {
namespace definition {

/**
 * Base class for all nodes of the definition tree.
 */
class DEFINITIONSHARED_EXPORT DefinitionNode
{
public:
    DefinitionNode(DefinitionNode* parent, const std::string &name, const std::string &type_name = "");
    virtual ~DefinitionNode();

    virtual void save(PackStream* stream) const;
    virtual void load(PackStream* stream);

    virtual void copy(DefinitionNode* destination) const;
    virtual void validate();

    inline const std::string &getName() const {return name;}
    virtual void setName(const std::string &name);

    inline const std::string &getTypeName() const {return type_name;}

    virtual Scenery* getScenery();

    inline const DefinitionNode *getParent() const {return parent;}
    inline const DefinitionNode *getRoot() const {return root;}
    inline DiffManager *getDiffManager() const {return diffs;}
    inline int getChildrenCount() const {return children.size();}

    /**
     * Return a string representation of the tree (mainly for debugging purposes).
     */
    virtual std::string toString(int indent = 0) const;

    /**
     * Return the path to this node, using '/' delimited syntax, with the first '/' being the root node.
     */
    std::string getPath() const;

    /**
     * Find a node in this tree, by its path (as returned by getPath).
     *
     * Return NULL if the path does not exists.
     */
    DefinitionNode *findByPath(const std::string &path) const;

    /**
     * Apply a diff to the internal value of this node.
     *
     * All internal node modifications should be done using this method, to be reversible.
     *
     * If *backward* is true, the diff will be reversed, instead of applied.
     *
     * Return true if the diff could be applied.
     */
    virtual bool applyDiff(const DefinitionDiff *diff, bool backward=false);

    /**
     * Add a watcher over this node.
     *
     * The watcher will receive DefinitionDiff objects when this node changes.
     */
    void addWatcher(DefinitionWatcher *watcher);

protected:
    void addChild(DefinitionNode* child);
    void removeChild(DefinitionNode* child);
    virtual DefinitionNode *findChildByName(const std::string name);

    /**
     * Get the size in bytes this child will consume when serialized to a stream.
     *
     * Return -1 if it can't be known. In this case, the saving will be done in a temporary
     * stream to know the exact size, which will not be very efficient.
     */
    int getStreamSize() const;

    /**
     * Add a diff to the DiffManager of this definition tree, for the current node.
     *
     * The manager will take immediate ownership of the diff, handling its freeing.
     *
     * The manager will decide if the diff should be committed and will call *applyDiff* if needed.
     */
    void addDiff(const DefinitionDiff *diff);

private:
    DefinitionNode *parent;
    DefinitionNode *root;
    DiffManager *diffs;
    std::string type_name;
    std::string name;
    std::vector<DefinitionNode*> children;
};

}
}

#endif // DEFINITIONNODE_H