#include <math.h>
#include "globals.h"
#include <grass/raster.h>

static View *pick_view, *zoom_view, *main_view;
static int target_flag;
static int zoom1(int,int);
static int cancel(void);

int 
zoom_point (void)
{
    static int use = 1;

    static Objects objects[]=
    {
	MENU("CANCEL",cancel,&use),
	INFO(" Mark center of area to be zoomed ",&use),
	OTHER(zoom1, &use),
	{0}
    };

    Input_pointer (objects);
    return 1;
}

static int zoom1(int x,int y)	/* called by Input_pointer */
{
    int top, bottom, left, right;
    int n,row,col;
    int nrows, ncols;
    struct Cell_head cellhd;
    int mag;
    double magnification();
    double north, south, east, west;
    double ns_range, ew_range, pnt_north, pnt_east,x_range,y_range;

    if (In_view (pick_view = VIEW_MAP1, x, y))
    {
	main_view = VIEW_MAP1;
	zoom_view = VIEW_MAP1_ZOOM;
	target_flag = 0;
    }
    else if (In_view (pick_view = VIEW_MAP2, x, y))
    {
	if (!pick_view->cell.configured)
	    return 0;	/* ignore the mouse event */
	main_view = VIEW_MAP2;
	zoom_view = VIEW_MAP2_ZOOM;
	target_flag = 1;
    }
    else if (In_view (pick_view = VIEW_MAP1_ZOOM, x, y))
    {
	if (!pick_view->cell.configured)
	    return 0;	/* ignore the mouse event */
	main_view = VIEW_MAP1;
	zoom_view = VIEW_MAP1_ZOOM;
	target_flag = 0;
    }
    else if (In_view (pick_view = VIEW_MAP2_ZOOM, x, y))
    {
	if (!pick_view->cell.configured)
	    return 0;	/* ignore the mouse event */
	main_view = VIEW_MAP2;
	zoom_view = VIEW_MAP2_ZOOM;
	target_flag = 1;
    }
    else
	return 0;	/* ignore the mouse event */
    if (!pick_view->cell.configured) return 0;	/* just to be sure */
/*
 * make sure point is within edges of image as well
 */
    if (x <= pick_view->cell.left) return 0;
    if (x >= pick_view->cell.right) return 0;
    if (y <= pick_view->cell.top) return 0;
    if (y >= pick_view->cell.bottom) return 0;

/*
 *
 ok, erase menu messages
*/
    Menu_msg("");

/* determine magnification of zoom */
    if (zoom_view->cell.configured)
    {
	if (zoom_view == pick_view)
	    mag = floor(magnification (zoom_view) + 1.0) + .1;
	else
	    mag = ceil(magnification (zoom_view)) + .1;
    }
    else
    {
	mag = floor(magnification (main_view) + 1.0) + .1;
    }
    if(!ask_magnification (&mag))
	return 1;
/* 
 * Determine the zoom window (ie, cellhd)
 */

    G_copy (&cellhd, &main_view->cell.head, sizeof(cellhd));

    if(target_flag == 0)
    {
        cellhd.ns_res = main_view->cell.ns_res / mag;
        cellhd.ew_res = main_view->cell.ew_res / mag;
    }

    cellhd.cols   = (cellhd.east - cellhd.west) / cellhd.ew_res;
    cellhd.rows   = (cellhd.north - cellhd.south) / cellhd.ns_res;

/* convert x,y to col,row */

    col  = view_to_col(pick_view,x);
    east = col_to_easting (&pick_view->cell.head, col, 0.5);
    col  = easting_to_col (&cellhd, east);

    row   = view_to_row(pick_view,y);
    north = row_to_northing (&pick_view->cell.head, row, 0.5);
    row   = northing_to_row (&cellhd, north);

if(target_flag == 0)
{
    ncols = zoom_view->ncols ;
    nrows = zoom_view->nrows ;

    n = cellhd.cols - col;
    if (n > col)
	n = col;
    if (n+n+1 >= ncols)
    {
	n = ncols/2;
	if (n+n+1 >= ncols) n--;
    }
    left = col - n;
    right = col + n;

    n = cellhd.rows - row;
    if (n > row)
	n = row;
    if (n+n+1 >= nrows)
    {
	n = nrows/2;
	if (n+n+1 >= nrows) n--;
    }

    top    = row - n;
    bottom = row + n;

    n = cellhd.rows - row;
    north = row_to_northing (&cellhd, top,0.0);
    west  = col_to_easting  (&cellhd,left,0.0);
    south = row_to_northing (&cellhd,bottom,1.0);
    east  = col_to_easting  (&cellhd,right,1.0);

    cellhd.north = north;
    cellhd.south = south;
    cellhd.east  = east ;
    cellhd.west  = west ;

    cellhd.rows = (cellhd.north-cellhd.south)/cellhd.ns_res;
    cellhd.cols = (cellhd.east-cellhd.west)/cellhd.ew_res ;

/*
 * Outline the zoom window on the main map
 * Turn previous one to grey.
 */
    if (zoom_view->cell.configured)
    {
	R_standard_color (GREY);
	Outline_cellhd (main_view, &zoom_view->cell.head);
    }

    R_standard_color (YELLOW);
    Outline_cellhd (main_view, &cellhd);

}
else
{
    top    = pick_view->cell.top;
    bottom = pick_view->cell.bottom;
    left   = pick_view->cell.left;
    right  = pick_view->cell.right;

    north = cellhd.north;
    south = cellhd.south;
    east  = cellhd.east;
    west  = cellhd.west;

    ns_range = north - south;
    ew_range = east - west;
    y_range  = (double) (bottom - top);
    x_range  = (double) (right  - left);

    pnt_north = north - (ns_range / y_range) * (double) row;
    pnt_east  = east  - (ew_range / x_range) * (double) (x_range - col);

    north = pnt_north + ns_range / mag / 2.0;
    south = pnt_north - ns_range / mag / 2.0;
    east  = pnt_east  + ew_range / mag / 2.0;
    west  = pnt_east  - ew_range / mag / 2.0;

    cellhd.north = north;
    cellhd.south = south;
    cellhd.east  = east ;
    cellhd.west  = west ;

    cellhd.rows   = zoom_view->bottom - zoom_view->top + 1;
    cellhd.cols   = zoom_view->right - zoom_view->left + 1;
    cellhd.ns_res = (north - south) / cellhd.rows;
    cellhd.ew_res = (east  - west)  / cellhd.cols;

    if(cellhd.ns_res > cellhd.ew_res)
       cellhd.ew_res = cellhd.ns_res;
    else
       cellhd.ns_res = cellhd.ew_res;

/*
 * Outline the zoom window on the main map
 * Turn previous one to grey.
 */
    if (zoom_view->cell.configured)
    {
	R_standard_color (GREY);
	Outline_cellhd (main_view, &zoom_view->cell.head);
    }

}

/*
 * zoom
 */
    if (target_flag)
	select_target_env();

    G_copy (&zoom_view->cell.head, &cellhd, sizeof (cellhd));

    if(target_flag)
    {
        R_standard_color (YELLOW);
        Outline_cellhd ( VIEW_MAP2, &zoom_view->cell.head);

	zoom_view->cell.ns_res = cellhd.ns_res;
	zoom_view->cell.ew_res = cellhd.ew_res;

        G_adjust_window_to_box (&cellhd, &zoom_view->cell.head, zoom_view->nrows            , zoom_view->ncols);
    }

    Configure_view (zoom_view, pick_view->cell.name, pick_view->cell.mapset,
	pick_view->cell.ns_res, pick_view->cell.ew_res);

    if (target_flag)
    { 
	zoomvect (zoom_view);
        VIEW_MAP2_ZOOM->cell.configured = 1;
    }
    else
        drawcell (zoom_view,0);

    select_current_env();
    display_points(1);

    return 1;	/* pop back */
}


static int 
cancel (void)
{
    return -1;
}