function S = strpad(obj, S, varargin)
%STRPAD String rightpadding
%   S = strpad(CA) applies rightpadding of spaces to all elements of the
%   cell array CA so that all have the same length and returns the cell
%   array S.
%
%   S = strpad(CA, n) sets extra rules for the padding. If n = 0 (default),
%   the longest string determines the length. If n > 0, n will be the
%   length until which padding is added. Note that if a string is longer
%   than n, it will not be truncated. If n < 0, -n is a margin, a number of
%   spaces added to the longest string and that then decides the final
%   length for all elements.
%
%   S = strpad(CA, n, '-truncate') truncates string if their length
%   exceeds the value of n > 0 (see above).

    % Handle flags
    [flg varargin] = flagParser(varargin, 'truncate');

    % Handle input
    p = inputParser();
    p.addRequired('S');
    p.addOptional('n', 0);
    p.parse(S, varargin{:});
    p = p.Results;
    
    S = p.S;
    n = p.n;
    
    % If S is an array, make it a cell array
    if isnumeric(S)
        S = cellfun(@num2str, num2cell(S), 'UniformOutput', false);
    end
    
    % If S is a string, make it a cell array
    if ischar(S)
        S = {S};
    end
    
    % Padding method depends on n
    if n > 0
        maxLength = p.n;
    else
        maxLength = max(max(cellfun(@length, S))) - n;
    end
    
    % For each element, add padding
    S = cellfun(@(s)([s char(zeros(1, maxLength-numel(s))+32)]), S, 'UniformOutput', false);
    
    % Truncation
    if flg.truncate
        S = cellfun(@(s)(s(1:maxLength)), S, 'UniformOutput', false);
    end
    
    % Display mode TODO
    if nargout > 0
        return;
    end

end