function [Data,han] = roms_bview(file,varname,time,bndy,grd,xcoord)
% $Id: roms_bview.m 358 2008-04-07 14:15:03Z zhang $
% [data,han] = roms_bview(file,var,time,bndy,grd,xcoord)
%
% file   = roms his/avg/rst etc nc file
% var    = variable to plot
% time   = time index into nc file
% bndy   = 'north','south','east','west'
% grd can be 
%       grd structure (from roms_get_grid)
%       grd_file name
%       [] (will attempt to get grid from roms file)
% xcoord = 'lon','lat', or 'dist' (default) to specify plot abscissa
%
% John Wilkin

if nargin < 5
  grd = [];
end
if nargin < 6
  xcoord = 'dist';
end

if isempty(grd)
  try
    grd = roms_get_grid(file,file);
  catch
    error([ 'Unable to generate grd structure from ' file])
  end
end

% trap case that varname was given with boundary included
nsew_check = findstr(varname,'_');
if ~isempty (nsew_check)
    bndy = varname((nsew_check+1):end);
else    
    varname = [varname '_' bndy];
end

% get appropriate z data for u, v or rho points
switch varname(1)
  case 'u'
    pos = '_u';
  case 'v'
    pos = '_v';
  otherwise
    pos = '_rho';
end
z = getfield(grd,[ 'z' pos(1:2)]);
lon = getfield(grd,[ 'lon' pos]);
lat = getfield(grd,[ 'lat' pos]);
m = getfield(grd,[ 'mask' pos]);

% choose z data for correct boundary
switch bndy(1)
  case 'w'
    z = z(:,:,1);
    lon = lon(:,1);
    lat = lat(:,1);
    m = m(:,1);
  case 'e'
    z = z(:,:,end);
    lon = lon(:,end);
    lat = lat(:,end);
    m = m(:,end);
  case 's'
    z = z(:,1,:);
    lon = lon(1,:);
    lat = lat(1,:);
    m = m(1,:);
  case 'n'
    z = z(:,end,:);
    lon = lon(end,:);
    lat = lat(end,:);
    m = m(end,:);
end
z = squeeze(z);
lon = lon(:);
lat = lat(:);
m = m(:);
m(find(m==0)) = NaN;
dist = cumsum([0; sw_dist(lat,lon,'km')]);

dist = repmat(dist',[size(z,1) 1]);
lon = repmat(lon',[size(z,1) 1]);
lat = repmat(lat',[size(z,1) 1]);
m = repmat(m',[size(z,1) 1]);

data = nc_varget(file,varname,[time-1 0 0],[1 -1 -1]);
% data = m.*data;

t = nc_varget(file,nc_attget(file,varname,'time'),[time-1],[1]);
tunits = nc_attget(file,nc_attget(file,varname,'time'),'units');
sec2day = 1;
if tunits(1:3) == 'sec'
  sec2day = 1/86400;
end
jday = julian(parsetnc(tunits))+t*sec2day;

if nargout > 0
  Data.var = data;
  Data.lon = lon;
  Data.lat = lat;
  Data.dist = dist;
  Data.mask = m;
  Data.z = z;
  Data.t = t;
  Data.tunits = tunits;
  Data.jday = jday;
end

% pcolor plot of the variable
titlestr = ...
  {['file: ' strrep_(file) ],...
  [upper(strrep_(varname)) ' - ' greg2str(jday)]};

switch xcoord
  case 'lon'
    hant = pcolorjw(lon,z,m.*data);
    xlabel('longitude')
  case 'lat'
    hant = pcolorjw(lat,z,m.*data);
    xlabel('latitude')
  otherwise
    hant = pcolorjw(dist,z,m.*data);
    xlabel('distance (m)')
end
title(titlestr)

if nargout > 1
  han = hant;
end