// This source code is property of the Computer Graphics and Visualization
// chair of the TU Dresden. Do not distribute in modified or unmodified form!
// Copyright (C) 2016 CGV TU Dresden - All Rights Reserved
//
/*************************************************************************
Abstract tool.
This class provides the basic superclass for all tools (pen, lines, circle...)
The constructor of the class takes a reference of a canvas_buffer as parameter
on which the pixels are changed.
The user of an instance of a derived class can use two different draw methods:
One version that operates only with the information of a single position
(e.g. the pen or the fill tools) and one that needs two pixel positions
(e.g. the line, circle or box). Also every tool maintains an element of
the enumerations of possible shapes (which are used for the preview tool).
For debugging purpose a method "set_text" is provided which modifies a
text stream that will be displayed in the main window.
*************************************************************************/
#pragma once

// needed for the set_text method
#include <sstream>
// declares the canvas_buffer
#include "canvas_buffer.h"

// Enumeration of possible shapes
enum ToolShape {
  TS_LINE,   // a line
  TS_BOX,    // a box
  TS_CIRCLE, // a circle
  TS_NONE    // no shape
};

class tool_base {
public:
  // Initialize the tool and store a reference of a canvas_buffer
  tool_base(canvas_buffer &canvas);

  // Draw with no point provided
  virtual void draw();
  // Draw with one point provided
  virtual void draw(int x, int y);
  // Draw with two points provided
  virtual void draw(int x0, int y0, int x1, int y1);
  // Draw with three points provided
  virtual void draw(int x0, int y0, int x1, int y1, int x2, int y2);

  // Get the shape that this tool will draw
  const ToolShape get_shape() const;

  // Put a text into the stream "stream" which will be displayed
  // in the main window
  virtual void set_text(std::stringstream &stream);

  // Return true if draw(x, y) is valid during dragging operations
  const bool is_tool_draggable() const;

protected:
  // The shape which is initialized in the constructor
  ToolShape shape;
  // A reference of the canvas store
  canvas_buffer &canvas;

  bool is_draggable;
};