#ifndef LAYOUT_H
#define LAYOUT_H

#include <windows.h>

#include "common.h"
#include "datalistview.h"
#include "pl.h"

void UpdateLayout(int w = 0, int h = 0);

/* Draggable portions of the client area, such as the split between
 * two list views, are implemented in Dragger singletons.
 *
 * HandleDown and HandleMove are called by the relevant window
 * procedures for WM_(NC)LBUTTONDOWN and WM_SETCURSOR. */

struct Dragger
{
	bool HandleDown();
	bool HandleMove();
protected:
	bool IsDown();
	bool IsDouble();
	virtual bool InDragArea(int x, int y);
	virtual void Drag(int x, int y);
	virtual void Reset();
	virtual void Done();
private:
	bool m_bActive = false;
	long m_time = 0;
};

/* Dragger for data list view (upper border). */

struct DlvDragger : public Dragger
{
private:
	bool InDragArea(int x, int y) override;
	void Drag(int x, int y) override;
	void Reset() override;
	void Done() override;
};

inline bool Dragger::IsDouble()
{
	const long time = GetMessageTime();
	const bool dbl = time-m_time <= static_cast<long>(GetDoubleClickTime());
	m_time = time;
	return dbl;
}

inline bool Dragger::IsDown()
{
	return GetKeyState(VK_LBUTTON) & 0x8000;
}

inline bool Dragger::HandleDown()
{
	extern HWND g_hWnd;
	POINT pt;
	require(GetRelativeCursorPos(g_hWnd, &pt));
	if (!InDragArea(pt.x, pt.y)) return false;

	if (IsDouble()) {
		m_bActive = false;
		Reset();
	} else
		m_bActive = true;

	return m_bActive;
}

inline bool Dragger::HandleMove()
{
	extern HWND g_hWnd;
	POINT pt;
	require(GetRelativeCursorPos(g_hWnd, &pt));

	extern HCURSOR g_hcSizeNs;
	bool r = true;
	if (InDragArea(pt.x, pt.y))
		SetCursor(g_hcSizeNs);
	else
		r = false;
	if (!m_bActive)
		return r;
	Drag(pt.x, pt.y);
	if (!IsDown()) {
		m_bActive = false;
		Done();
	}
	return r;
}

#endif