wirelessnetworkSupportPackageCheck;

% Reset the random number generator
rng('default');

selectFTPTrafficModel = 'localFTPModel';

% Create an FTP application traffic pattern object with default properties
ftpObj = networkTrafficFTP;

if  strcmp(selectFTPTrafficModel, 'localFTPModel')
    % Set truncated log-normal distribution mu value for file size calculation
    ftpObj.LogNormalMu = 10; 

    % Set truncated log-normal distribution sigma value for file size calculation
    ftpObj.LogNormalSigma = 1;

    % Set truncated log-normal distribution upper limit in MB
    ftpObj.UpperLimit = 5;

    % Set exponential distribution mean value for reading time in milliseconds
    ftpObj.ExponentialMean = 100;
else
    % Set file size in MB
    ftpObj.FixedFileSize = 0.5;

    if strcmp(selectFTPTrafficModel, 'ftpModel2')
        % Set exponential distribution mean value for reading time in milliseconds
        ftpObj.ExponentialMean = 100;
    else % FTP Model 3
        % Set exponential distribution mean value for reading time in milliseconds
        ftpObj.PoissonMean = 100;
    end

end

% Set simulation time in milliseconds
simTime = 500;

% Simulation time left
remSimTime = simTime;

% Validate simulation time
validateattributes(simTime,{'numeric'},{'real','scalar','finite'});

% Generated packet count
packetCount = 0;

% Initialize arrays to store outputs for visualization
% Packet generation times in milliseconds
generationTime = zeros(5000,1);

% Initialize arrays to store outputs for visualization
% Packet generation times in milliseconds
sumPacketSizes = zeros(5000,1);

% Time between two consecutive packet transfers in milliseconds
packetIntervals = zeros(5000,1);

% Packet sizes in bytes
packetSizes = zeros(5000,1);

% TCP/IP header size
tcpIPHeaderSize = 40;

% FTP file size in bytes
fileSizes = zeros(simTime,1);

dt = 0; % Time remaining to generate next packet

% Loop over the simulation time, generating FTP application traffic
% pattern and saving the dt and packet size values for visualization.
while remSimTime > 0
    packetCount = packetCount+1; % Increment packet count
    % Call generate method and store outputs for visualization
    [dt, packetSizes(packetCount)] = generate(ftpObj, dt);
    packetIntervals(packetCount) = dt;
    % Remove the TCP/IP header
    packetSizes(packetCount) = packetSizes(packetCount) - tcpIPHeaderSize;
    % Store packet generation time for visualization
    generationTime(packetCount+1) = ...
        generationTime(packetCount) + packetIntervals(packetCount);
    sumPacketSizes(packetCount+1) = ...
        sumPacketSizes(packetCount) + packetSizes(packetCount);
    if dt > 0
        fileSizes(simTime-remSimTime+1) = sumPacketSizes(packetCount+1);
        sumPacketSizes(packetCount+1) = 0;
    end
    % Update simulation time
    remSimTime = remSimTime - dt;
end

% Packet Number Versus Packet Intervals (dt)
% Plot graph to see packet intervals
pktIntervalsFig = figure(Name='Packet intervals',NumberTitle='off');
pktIntervalsAxes = axes(pktIntervalsFig);
plot(pktIntervalsAxes,packetIntervals(1:packetCount));
grid on;
title(pktIntervalsAxes,'Packet Number Versus Reading Time');
xlabel(pktIntervalsAxes,'Packet Number');
ylabel(pktIntervalsAxes,'Reading Time in Milliseconds');

% Plot to see different packet sizes
pktSizesFig = figure(Name='Packet sizes',NumberTitle='off');
pktSizesAxes = axes(pktSizesFig);
plot(pktSizesAxes,packetSizes(1:packetCount));
grid on;
title(pktSizesAxes,'Packet Number Versus Packet Size');
xlabel(pktSizesAxes,'Packet Number');
ylabel(pktSizesAxes,'Packet Size in Bytes');

% To obtain a correct plot, configure offeredTraffic so that the reading
% time is greater than the transmission time.

% Offered traffic per user in bits per second
offeredTraffic = 40e6;

% Find all file sizes
[tIdx]=find(fileSizes>0);
% Calculate transmission times of the packet in milliseconds
txTime = ceil((fileSizes(tIdx)*8/(offeredTraffic))*1e3);

% Estimate step increment per millisecond
stepIncr = fileSizes(tIdx)./txTime;

% Update file size after each step increment
for i = 1:numel(tIdx)
    a=1:txTime(i);
    fileSizes(tIdx(i)+1:tIdx(i)+txTime(i)) = max(fileSizes(tIdx(i))-a*stepIncr(i),0);
end

% Stem graph of FTP application traffic pattern (Packet sizes
% different files at different packet generation times)
ftpPatternFig = figure(Name='FTP application traffic pattern', ...
    NumberTitle='off');
ftpPatternAxes = axes(ftpPatternFig);
stem(ftpPatternAxes, ...
    fileSizes,Marker='none');
grid on;
title(ftpPatternAxes,'Packet Generation Time Versus File Size');
ylim([0 1.5*max(fileSizes)]);
ylabel(ftpPatternAxes,'File Size in Bytes');
xlabel(ftpPatternAxes,'Time in milliseconds');