function output = save(obj)
%SAVE Save a PricklyPear run
%   save(PP(0)) stores the unsaved run from experiment(PP) to the next
%   available irec. Storing already saved runs is not allowed.

    % The object must be the unsaved simulation (irec = 0)
    assert(~isempty(experiment(obj)), 'Please specify an experiment');
    assert(~isempty(obj.irec) && obj.irec == 0, 'Only the unsaved simulation (irec = 0) can be saved');
    
    % The unsaved experiment must exist
    assert(exist(obj) == true, 'No unsaved simulation found');
    
    % What is the next available irec?
    parobj = parent(obj);
    nextIrec = [];
    ii = 1;
    while isempty(nextIrec)
        if ~exist(child(parobj, ii), 'full', true)
            nextIrec = ii;
        else
            ii = ii + 1;
        end
    end
    
    % Move data
    [unused unused] = mkdir(obj.datadir());
    for ii = 1:numel(obj.sim_channels)
        movefile(fullfile(obj.datadir(), sprintf('run_unsaved__vm_%s.txt', obj.sim_channels{ii})),...
                 fullfile(obj.datadir(), sprintf('run_%05i__vm_%s.txt', nextIrec, obj.sim_channels{ii})));
    end
    movefile(fullfile(obj.datadir(), sprintf('run_unsaved__evt_contra.txt')),...
             fullfile(obj.datadir(), sprintf('run_%05i__evt_contra.txt', nextIrec)));
    movefile(fullfile(obj.datadir(), sprintf('run_unsaved__evt_ipsi.txt')),...
             fullfile(obj.datadir(), sprintf('run_%05i__evt_ipsi.txt', nextIrec)));
    movefile(fullfile(obj.datadir(), sprintf('run_unsaved__properties.ppbin')),...
             fullfile(obj.datadir(), sprintf('run_%05i__properties.ppbin', nextIrec)));
    
    % Notify the user or output the irec
    output = nextIrec;
    if nargout == 0
        fprintf('Run saved as run %i\n', nextIrec);
    end
    
end