function build_svn_game(varargin)
    % build_svn_game svn_rev1 svn_rev2
    % when both svn_rev1 and svn_rev2 are NOT supplied:
    %          no backup software is build
    %          normal software from head revision is build
    % when svn_rev1 IS supplied and svn_rev2 is NOT supplied:
    %          backup software from svn_rev1 is build
    %          normal software from head revision is build
    % when both svn_rev1 and svn_rev2 ARE supplied:
    %          backup software from svn_rev2 is build
    %          normal software from svn_rev1 is build
    curdir = cd;
    
    svn_head = 0;
    [error,result] = system('sudo /etc/Robocup/robocup_network');
    [error,result] = system('timeout 4 svn info http://robocup.wtb.tue.nl/svn/techunited/ | grep Revision');
    if(error > 1)
        warning(result);
        return;
    end
    svn_head = getRevision(result);
    
    
    if(nargin == 0)
        % checkout latest svn version, no backup
        svn_rev = svn_head;
        svn_backup_rev = 0;
    elseif(nargin == 1)
        % checkout latest svn version, backup rev varargin(1)
        svn_rev = svn_head;
        if(ischar(varargin{1}))
            svn_backup_rev = str2num(varargin{1});
        else
            svn_backup_rev = varargin{1};
        end
    elseif(nargin == 2)
        % checkout svn rev varargin(1), backup rev varargin(2)
        if(ischar(varargin{1}))
            svn_rev = str2num(varargin{1});
        else
            svn_rev = varargin{1};
        end
        if(ischar(varargin{2}))
            svn_backup_rev = str2num(varargin{2});
        else
            svn_backup_rev = varargin{2};
        end
    else
        warning('Too many input arguments.');
        return;
    end
    
    cd /home/robocup/svn/
    [error,result] = system('svn st | grep ^M');
    if(error > 1)
        warning('Cannot get modified files, aborting');
        disp(result);
        return;
    else
        if(isempty(result))
            disp('No modified files.');
        else
            disp('Modified files:');
            disp(result);
        end
        [error,result] = system('timeout 4 svn info | grep Revision');
        if(error > 1)
            warning(result);
            return;
        end
        cur_rev = getRevision(result);
        disp(['Current revision: ' num2str(cur_rev)]);
        reply = input('Continue with update (all changes will be reverted)? Y/n: ', 's');
        if isempty(reply)
            reply = 'Y';
        end
        if(upper(reply) == 'N')
            return;
        end
        if(svn_rev == svn_head)
            disp('Continuing svn update to HEAD');
        else
            disp(['Continuing svn update to revision ' num2str(svn_rev)]);
        end
        [error,result] = system(['svn revert -R .']);
        if(error > 1)
            warning('Reverting changes failed.');
            disp(result);
            return;
        end
        [error,result] = system(['svn up -r ' num2str(svn_rev)]);
        if(error > 1)
            warning('Updating svn failed.');
            disp(result);
            return;
        end
        disp(result);
        
        % build normal software
        disp('');
        disp('Making all software...');
        save('build_game_settings');
%         make_all_install;
%         build_turtle_motion4W;
%         build_all;
        cd /home/robocup/svn/
        load('build_game_settings');
        disp('Done building the normal software');
        
        
        if(svn_backup_rev > 0)
            disp(['Svn update to revision ' num2str(svn_backup_rev)]);
            [error,result] = system(['svn up -r ' num2str(svn_backup_rev)]);
            if(error > 1)
                warning(['Updating svn to revision ' num2str(svn_backup_rev) ' failed.']);
                disp(result);
                return;
            end
            disp(result);
            % build backup software
            disp('');
            disp('Making all backup software...');
%             make_all_install;
%             build_turtle_motion4W('backup');
%             build_all('backup');
            cd /home/robocup/svn/
            load('build_game_settings');
            delete('build_game_settings.mat');
        end
    end
    
    cd(curdir);
    
    %% summary
    disp('');
    disp('');
    disp(['All software has been build, revision ' num2str(svn_rev) ':']);
    fprintf(['    motion_turtle',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/Motion/motion_turtle'),'\n']);
    fprintf(['    vision_turtle',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/Vision/vision_turtle'),'\n']);
    fprintf(['    worldmodel',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/WorldModel/worldmodel'),'\n']);
    fprintf(['    motion_keeper',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/Motion/motion_keeper'),'\n']);
    fprintf(['    motion_turtle_4W',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/Motion/motion_turtle_4W'),'\n']);
    if(svn_backup_rev > 0)
        disp(['Backup, revision ' num2str(svn_backup_rev) ':']);
        fprintf(['    motion_turtle_backup',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/Motion/motion_turtle_backup'),'\n']);
        fprintf(['    vision_turtle_backup',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/Vision/vision_turtle_backup'),'\n']);
        fprintf(['    worldmodel_backup',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/WorldModel/worldmodel_backup'),'\n']);
        fprintf(['    motion_keeper_backup',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/Motion/motion_keeper_backup'),'\n']);
        fprintf(['    motion_turtle_4W_backup',file_creation_date('/home/robocup/svn/trunk/src/Turtle2/Motion/motion_turtle_4W_backup'),'\n']);
    end
end

function rev = getRevision(string)
    [~,~,~,~,rev_str] = regexp(string, '.*: (\d+)');
    rev = str2num(rev_str{1}{1});
end

function str = file_creation_date(file)
    try
        ftime = dir(file);
        str=([', built on ',datestr(ftime.datenum,'dd-mmm, HH:MM')]);
    catch
        str = '';
    end
end