function sts = match(item, spec)

% function sts = match(item, spec)
% This function is an implementation of find to search the cfg tree for
% certain entries.
%
% sts = match(item, spec)
% Spec must be a cell array of struct arrays with one or more fields. Each
% struct must contain two fields - 'name' and 'value'.
% An item matches, if it has a field with the specified field name and the
% contents of this field equals the contents of spec.value. If the field
% name is 'class', an item matches, if its class name is equal to
% spec.value.
% Matches within each struct array are OR-concatenated, while matches
% between struct arrays are AND-concatenated.
% An empty spec always matches.
% Special matching rules for cfg_files apply to the .filter field, if
% both item.filter and spec.value are one of the special types 'any',
% 'image', 'nifti', 'mat', 'xml', 'batch', 'dir':
% A .filter 'any' matches any spec.value. All other filters only match if
% strcmpi(item.filter,spec.value) is true. Currently, 'nifti' and 'image'
% filters are treated as equivalent.
% Checking the equivalence of two regular expressions is a demanding
% task. Therefore, no matching is performed if item.filter or spec.value
% are regular expressions and this match will always be true.
%
% This code is part of a batch job configuration system for MATLAB. See 
%      help matlabbatch
% for a general overview.
%_______________________________________________________________________
% Copyright (C) 2007 Freiburg Brain Imaging

% Volkmar Glauche
% $Id: match.m 4898 2012-09-05 13:40:16Z volkmar $

rev = '$Rev: 4898 $'; %#ok

% match an empty spec
sts = true;

for k = 1:numel(spec)
    % Assume no match
    sts = false;
    for l = 1:numel(spec{k})
        switch spec{k}(l).name,
            % don't try any matching of regexp filters
            case 'filter',
                specflt = cfg_getfile('regfilter');
                specflt = {specflt.typ};
                ifilter = item.filter;
                [ifilter{strcmpi(item.filter,'nifti')}] = deal('image');
                sfilter = cellstr(spec{k}(l).value);
                [sfilter{strcmpi(sfilter,'nifti')}] = deal('image');
                if isequal(ifilter, sfilter)
                    sts = true;
                elseif any(strcmpi(ifilter,'any'))
                    sts = any(~strcmpi(sfilter,'dir'));
                elseif ~isempty(intersect(sfilter,specflt)) && ~isempty(intersect(ifilter,specflt))
                    sts = ~isempty(intersect(sfilter,ifilter));
                else
                    sts = true;
                end;
            case 'ufilter',
                sts = true;
            case 'num',
                sts = true;
            case 'class'
                sts = strcmpi(spec{k}(l).value,class(item));
            otherwise
                spec1{1}(1) = spec{k}(l);
                sts = match(item.cfg_item, spec1);
        end;
        if sts
            % OR: success on first match
            break;
        end;
    end;
    if ~sts
        % AND: fail on first non-match
        break;
    end;
end;