//
// Viewport.cc for pekwm
// Copyright (C)  2003-2004 Claes Nasten <pekdon{@}pekdon{.}net>
//
// This program is licensed under the GNU GPL.
// See the LICENSE file for more information.
//

#include "../config.h"
#include "Viewport.hh"
#include "Atoms.hh"
#include "Config.hh"
#include "PScreen.hh"
#include "PWinObj.hh"
#include "PDecor.hh"
#include "ScreenResources.hh"
#include "Workspaces.hh"

#ifdef DEBUG
#include <iostream>
using std::cerr;
using std::endl;
#endif // DEBUG
using std::list;

//! @brief Viewport constructor
Viewport::Viewport(uint ws, const std::list<PWinObj*> &wo_list) :
_ws(ws), _wo_list(wo_list),
_x(0), _y(0), _cols(1), _rows(1)
{
	_scr = PScreen::instance();

	// init viewport
	reload();
}

//! @brief Viewport destructor
Viewport::~Viewport(void)
{
}

//! @brief Moves the viewport to x y, optionally warping the pointer
//! @param x X position to move to
//! @param y Y position to move to
//! @param warp Wheter or not to warp the pointer, defaults to false
//! @param wx Mouse warp x position, defaults to 0
//! @param wy Mouse warp y position, defaults to 0
bool
Viewport::move(int x, int y, bool warp, int wx, int wy)
{
	// validate position
	if (x < 0)
		x = 0;
	else if (x > _x_max)
		x = _x_max;
	if (y < 0)
		y = 0;
	else if (y > _y_max)
		y = _y_max;

	// if the position has changed, let's move all frames
	if ((_x != x) || (_y != y)) {

		// calculate relative offset
		int d_x = _x - x;
		int d_y = _y - y;

		_x = x;
		_y = y;

		// Update _NET_DESKTOP_VIEWPORT
		hintSetViewport();

		if (warp == true)
			XWarpPointer(_scr->getDpy(), None, _scr->getRoot(), 0, 0, 0, 0, wx, wy);

		list<PWinObj*>::const_iterator it = _wo_list.begin();
		for (; it != _wo_list.end(); ++it) {
			if (((*it)->getWorkspace() == _ws) && ((*it)->isSticky() != true)) {
				(*it)->move((*it)->getX() + d_x, (*it)->getY() + d_y);
				// FIXME: This won't send any configure requests to the client,
				// should we overload the Frame::move or add a special case?
			}
		}

		return true;
	}

	return false;
}

//! @brief Moves the viewport in direction dir, optionally warping the pointer
//! @param dir Direction to move
//! @param warp Wheter or not to warp the pointer, defaults to true
bool
Viewport::moveDirection(DirectionType dir, bool warp)
{
	int n_x = _x, n_y = _y;
	int warp_x, warp_y;
	uint warp_d = Config::instance()->getScreenEdgeSize() * 2;
	if (warp_d == 0)
		warp_d = 2;

	_scr->getMousePosition(warp_x, warp_y);

	switch (dir) {
	case DIRECTION_UP:
		n_y -= _v_height;

		if (n_y < 0) {
			warp_y = _v_height + n_y;
		} else {
			warp_y = _v_height - warp_d;
		}
		break;
	case DIRECTION_DOWN:
		n_y += _v_height;

		if (n_y > _y_max) {
			warp_y = _v_height + _y - _y_max;
		} else {
			warp_y = warp_d;
		}
		break;
	case DIRECTION_LEFT:
		n_x -= _v_width;

		if (n_x < 0) {
			warp_x = _v_width + n_x;
		} else {
			warp_x = _v_width - warp_d;
		}
		break;
	case DIRECTION_RIGHT:
		n_x += _v_width;

		if (n_x > _x_max) {
			warp_x = _v_width + _x - _x_max;
		} else {
			warp_x = warp_d;
		}
		break;
	default:
		// Do nothing
		break;
	};

	return (move(n_x, n_y, warp, warp_x, warp_y));
}

//! @brief Initiates moving of the viewport starting at x y
void
Viewport::moveDrag(int x, int y)
{
	int status =
		_scr->grabPointer(_scr->getRoot(), ButtonMotionMask|ButtonReleaseMask,
											ScreenResources::instance()->getCursor(ScreenResources::CURSOR_MOVE));

	if (status != true)
		return;

	// apply virtual desktop offset
	x -= _x;
	y -= _y;

	bool exit = false;

	XEvent ev;
	while (exit != true) {
		XMaskEvent(_scr->getDpy(), ButtonReleaseMask|ButtonMotionMask, &ev);

		switch (ev.type) {
		case MotionNotify:
			move(ev.xmotion.x_root - x, ev.xmotion.y_root - y);
			break;
		case ButtonRelease:
			exit = true;
			break;
		default:
			// Do nothing
			break;
		}
	}

	_scr->ungrabPointer();
}

//! @brief Moves the viewport to the column and row making the wo visible
//! @param wo PWinObj to make visible
bool
Viewport::moveToWO(PWinObj *wo)
{
	// make sure it is possible to move to the WO
	makeWOInsideVirtual(wo);

	return (move(getCol(wo) * _v_width, getRow(wo) * _v_height));
}

//! @brief Moves the viewport x_off and y_off pixels from current position
void
Viewport::scroll(int x_off, int y_off)
{
	move(_x + x_off, _y + y_off);
}

//! @brief Moves the viewport to column col and row row
void
Viewport::gotoColRow(uint col, uint row)
{
	move(col * _v_width, row * _v_height);
}

//! @brief Updates the viewport related hints
void
Viewport::hintsUpdate(void)
{
	hintSetViewport();
	hintSetGeometry();
	hintSetWorkarea();
}

//! @brief Updates the _NET_DESKTOP_VIEWPORT hint
void
Viewport::hintSetViewport(void)
{
	AtomUtil::setPosition(_scr->getRoot(),
												EwmhAtoms::instance()->getAtom(NET_DESKTOP_VIEWPORT),
												_x, _y);
}

//! @brief Updates the _NET_DESKTOP_GEOMETRY hint
void
Viewport::hintSetGeometry(void)
{
	AtomUtil::setPosition(_scr->getRoot(),
												EwmhAtoms::instance()->getAtom(NET_DESKTOP_GEOMETRY),
												_width, _height);
}

//! @brief Updates the _NET_WORKAREA hint
void
Viewport::hintSetWorkarea(void)
{
	int x, y;
	uint width, height;

	// FIXME: Expected behaviour?
	x = _x + _scr->getStrut()->left;
	y = _y + _scr->getStrut()->top;
	width = _v_width - x - _scr->getStrut()->right;
	height = _v_height - y - _scr->getStrut()->bottom;

	CARD32 workarea[] = { x, y, width, height };

	XChangeProperty(_scr->getDpy(), _scr->getRoot(),
									EwmhAtoms::instance()->getAtom(NET_WORKAREA),
									XA_CARDINAL, 32, PropModeReplace, (uchar *) workarea, 4);
}

#ifdef HAVE_XRANDR
//! @brief Refetches the root-window size and takes appropriate actions.
void
Viewport::updateGeometry(void)
{
	reload();
}
#endif // HAVE_XRANDR

//! @brief Reloads confiuration
void
Viewport::reload(void)
{
	_cols = Config::instance()->getViewportCols();
	_rows = Config::instance()->getViewportRows();

	// setup boundaries
	_v_width = _scr->getWidth();
	_v_height = _scr->getHeight();

	_width = _cols * _v_width;
	_height = _rows * _v_height;

	_x_max = _width - _v_width;
	_y_max = _height - _v_height;

	makeAllInsideVirtual();

	hintsUpdate(); // make sure workarea is up to date
}

//! @brief Makes sure all PWinObjs are inside the real screen
void
Viewport::makeAllInsideReal(void)
{
	list<PWinObj*>::const_iterator it = _wo_list.begin();
	for (; it != _wo_list.end(); ++it) {
		if (((*it)->getType() == PWinObj::WO_FRAME) &&
				((*it)->getWorkspace() == _ws)) {

			makeWOInsideReal(*it);
		}
	}
}

//! @brief Make sure all PWinObjs are inside the virtual screen
void
Viewport::makeAllInsideVirtual(void)
{
	list<PWinObj*>::const_iterator it = _wo_list.begin();
	for (; it != _wo_list.end(); ++it) {
		if (((*it)->getType() == PWinObj::WO_FRAME) &&
				((*it)->getWorkspace() == _ws)) {

			makeWOInsideVirtual(*it);
		}
	}
}

//! @brief Make sure wo is inside the real screen
//! @param wo PWinObj to make inside real screen
void
Viewport::makeWOInsideReal(PWinObj *wo)
{
	// NOTE: passing false to move, we don't want to corrupt
	//  _PEKWM_FRAME_VPOS hint with invalid position information

	// fix horizontal
	if (wo->getRX() < 0) {
		wo->move(0, wo->getY(), false);
	} else if (wo->getX() > signed(_v_width)) {
		wo->move(_v_width - wo->getWidth(), wo->getY(), false);
	}

	// fix vertical
	if (wo->getBY() < 0) {
		wo->move(wo->getX(), 0, false);
	} else if (wo->getY() > signed(_v_height)) {
		wo->move(wo->getX(), _v_height - wo->getHeight(), false);
	}
}

//! @brief Make sure wo is inside the virtual screen
//! @param wo PWinObj to make inside virtual screen
void
Viewport::makeWOInsideVirtual(PWinObj *wo)
{
	// fix horizontal
	if ((wo->getRX() + _x) < 0) {
		wo->move(0, wo->getY());
		wo->moveVirtual(wo->getX() + _x, wo->getY() + _y);
	} else if ((wo->getX() + _x) > signed(_width)) {
		wo->move(_width - _x - wo->getWidth(), wo->getY());
		wo->moveVirtual(wo->getX() + _x, wo->getY() + _y);
	}

	// fix vertical
	if ((wo->getBY() + _y) < 0) {
		wo->move(wo->getX(), 0);
		wo->moveVirtual(wo->getX() + _x, wo->getY() + _y);
	} else if ((wo->getY() + _y) > signed(_height)) {
		wo->move(wo->getX(), _height - _y - wo->getHeight());
		wo->moveVirtual(wo->getX() + _x, wo->getY() + _y);
	}
}