classdef Equipment < handle
    %EQUIPMENT Summary of this class goes here
    %   Detailed explanation goes here
    
    properties (SetAccess=private)
        name
        tcp
        channel
        locked
    end
    properties (Dependent, SetAccess=private)
        error
    end
    
    methods
        function ecq = Equipment(ipAddress,port,channel)
            ecq.tcp = Equipment.getTCP(ipAddress,port);
            ecq.locked = false;
            ecq.channel = channel;
            ecq.name = ecq.idn();
        end
        function id = idn(ecq)
            id = ecq.query('*idn?');
        end
        
        function unlock(ecq)
        end
        
        function lock(ecq)
        end
        
        function delete(ecq)
            %zorgen dat het device geunlocked is!
            %ecq.unlock;
            Equipment.getTCP(ecq.tcp.RemoteHost,-1);
        end
        
        function write(ecq,message)
            if ecq.channel >= 0
                fprintf(ecq.tcp,['++addr ', num2str(ecq.channel)]);
            end
            fprintf(ecq.tcp, message);
        end
        
        function output = read(ecq)
            if ecq.channel >= 0
                fprintf(ecq.tcp,'++read');
            end
            output = fscanf(ecq.tcp);
        end
        
        function output = query(ecq,message)
            write(ecq,message);
            output = read(ecq);
        end
        
        function e = get.error(ecq)
            e = ecq.query('SYSTem:ERRor?');
        end
    end
    methods (Static)
        function tcpobject = getTCP(ipAddress,port)
            persistent tcpconnection;
            ipname = Equipment.ip2structname(ipAddress);
            if port > 0
                if isempty(tcpconnection)
                    tcpconnection = struct;
                end

                if ~isfield(tcpconnection, ipname)
                    tcpconnection.(ipname).tcp = tcpip(ipAddress,port);
                    tcpconnection.(ipname).nopen = 1;
                    fopen(tcpconnection.(ipname).tcp);
                else
                    tcpconnection.(ipname).nopen = tcpconnection.(ipname).nopen + 1;
                end
                tcpobject = tcpconnection.(ipname).tcp;
            elseif port == -1
                if tcpconnection.(ipname).nopen > 1
                    tcpconnection.(ipname).nopen = tcpconnection.(ipname).nopen - 1;
                else
                    fclose(tcpconnection.(ipname).tcp);
                    tcpconnection = rmfield(tcpconnection,ipname);
                end
            else
                error([num2str(port),' is not a valid port number try a value between 1 and 65535.']);
            end
        end
        
        function iptest(ipAddress)
            validip = regexp(ipAddress,'^(?:(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])\.(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])\.(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])\.(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9]))$', 'once');
            if isempty(validip)
                error('Invalid IP-address');
            end
        end
        function structname = ip2structname(ipAddress)
            Equipment.iptest(ipAddress);
            ipmatch = regexprep(ipAddress,'\.','_');
            structname = ['ip',ipmatch];
        end
    end
end