function sconfounds = spm_eeg_read_bsa(bsa)
% This function reads a definition of spatial confounds from a BESA
% *.bsa file and returns an sconfounds struct with the following fields
% .label - labels of channels
% .coeff - matrix of coefficients (channels x components)
% .bad - logical vector - channels marked as bad.
% _______________________________________________________________________
% Copyright (C) 2008 Wellcome Trust Centre for Neuroimaging

% Vladimir Litvak

sconfounds = [];
sconfounds.coeff = [];

bsain=fopen(bsa, 'r');

for i=1:3
    fgetl(bsain);
end

i = 1;
while ~feof(bsain)
    line=fgetl(bsain);
    startind= findstr(line, 'CVecOrig|')+9;
    endind= findstr(line, 'CVecChanLabels')-1;

    coeffstr=line(startind:endind);
    coeffs=sscanf(strrep(coeffstr, '|', ' '), '%f');
    coeffs=coeffs(2:end);

    startind= endind+15;
    endind= findstr(line, 'CVec|')-1;

    bsalabel=deblank(tokenize(line(startind:endind), '|'));
    
    sconfounds.label = bsalabel;
    sconfounds.coeff = [sconfounds.coeff coeffs(:)];
    
    i = i+1;
end

sconfounds.label = sconfounds.label(:);

sconfounds.bad = zeros(size(sconfounds.label));
sconfounds.bad(strmatch('*', sconfounds.label)) = 1;

badind = find(sconfounds.bad);

for i = 1:length(badind)
  sconfounds.label{badind(i)} = sconfounds.label{badind(i)}(2:end);
end

fclose(bsain);


function [tok] = tokenize(str, sep, rep)

% TOKENIZE cuts a string into pieces, returning a cell array
%
% Use as
%   t = tokenize(str, sep)
%   t = tokenize(str, sep, rep)
% where str is a string and sep is the separator at which you want
% to cut it into pieces.
%
% Using the optional boolean flag rep you can specify whether repeated
% seperator characters should be squeezed together (e.g. multiple
% spaces between two words). The default is rep=1, i.e. repeated
% seperators are treated as one.

% Copyright (C) 2003-2006, Robert Oostenveld
%
% $Log: tokenize.m,v $
% Revision 1.5  2006/05/10 07:15:22  roboos
% allow for squeezing multiple separators into one
%
% Revision 1.4  2006/01/30 14:56:41  roboos
% fixed another stupid bug in previous cvs commit
%
% Revision 1.3  2006/01/30 14:55:44  roboos
% fixed stupid bug in previous cvs commit
%
% Revision 1.2  2006/01/30 13:38:18  roboos
% replaced dependency on strtok by more simple code
% changed from dos to unix
%
% Revision 1.1  2005/05/23 13:47:51  roboos
% old implementation, new addition to CVS for fieldtrip release
%

tok = {};
f = find(str==sep);
f = [0, f, length(str)+1];
for i=1:(length(f)-1)
  tok{i} = str((f(i)+1):(f(i+1)-1));
end

if nargin<3 || rep
  % remove empty cells, which occur if the separator is repeated (e.g. multiple spaces)
  tok(find(cellfun('isempty', tok)))=[];
end