#ifndef _DISPLAY_H
#define _DISPLAY_H

#include "CPstring.h"

// forward reference for tree....
struct TreeNode;

// Display Class: animates drawing of trees
//
// Display(ostream & OutputStream,           -- Constructor (stream and
//         displayColor defaultColor=black); -- color to draw)
// void InitializeTreeNode(TreeNode  * node) -- Initially Draws Node and
//                                              line to its parent
// void FlashNode(TreeNode * node );  -- turns node on and off with a delay
// void MoveNode(TreeNode * node);  -- Moves a node on the screen
// void ConnectNodeToParent(TreeNode * node); -- draws line from child to 
//                                               parent
// void DisconnectNodeFromParent (TreeNode * node); deletes line from child
//                                                  to parent
// void DeleteNode (TreeNode * node);  deletes node from animation
// void SetNodeDefaultColor(TreeNode * node);   sets node to the default color
// void SetNodeColor(TreeNode * node,           sets node to specifiec color
//                   displayColor color);
// void UpdateLevelCount(int maxLevel);         Update # of levels in tree
// void Stall(int delay);  -- causes a delay in samba


class Display
{
  public:
    static const int DELAY_TIME;  //Default time to stall
    enum displayColor {black, red, blue, orange, yellow, green, cyan};

    Display(ostream & OutputStream,             // constructor stream and
	    displayColor defaultColor=black);   // default color
    void InitializeTreeNode(TreeNode * node);   // Issue initial
                                                // samba display command
    void FlashNode(TreeNode *node);             // Have node flash
    void MoveNode(TreeNode * node);             // Node changes position
    void ConnectNodeToParent(TreeNode * node);  // draw line from node
                                                // to parent
    void DisconnectNodeFromParent               // delete line from node
	(TreeNode * node);                      // to parent
    void DeleteNode(TreeNode * node);           // delete node in samba
    void SetNodeColor(TreeNode * node,          // set color of node in
		      displayColor color);      // samba
    void SetNodeDefaultColor(TreeNode * node);  // set color of node
                                                // to default value
    void UpdateLevelCount(int maxLevel);        // update # of levels
                                                // in tree
    void Stall(int delay = DELAY_TIME);         // tell samba to stall
    
  private:
    double ComputeXPosition(int level, int id); // Compute x position
    double ComputeYPosition(int level);         // Compute y position
    string GetNodeColor(displayColor color);    // get string for color
    void DeleteLine(int fromLevel, int fromID,  // Delete line between
		    int toLevel, int toID);     // two nodes
    void DrawLine(int fromLevel, int fromID,    // draw line between 2 nodes
		  int toLevel, int toID);
    
    ostream & myOutputStream;	  // output stream for data
    int  myMaxLevel;              //  # of levels in tree
    double myLowLevelMaxNodes;    // # of nodes on bottom level
    int myID;                     // ID # of display
    displayColor myDefaultColor;  // Color for default use
};

#endif