% Check if the 'Communications Toolbox Library for the Bluetooth Protocol'
% support package is installed or not.
commSupportPackageCheck('BLUETOOTH');

% Create objects for GATT-server and GATT-client devices.
gattServer = helperBLEGATTServer;
gattClient = helperBLEGATTClient;

% Preallocate a variable to store the generated link layer packets.
pcapPackets = cell(1, 9);
count = 1;

% Configure a GATT client to discover services available at the server.
gattClient.SubProcedure = 'Discover all primary services';
serviceDiscReqPDU = generateATTPDU(gattClient);

% Transmit the application data (|serviceDiscReqPDU|) to the server through
% PHY.
[bleWaveform, pcapPackets{count}] = helperBLETransmitData(serviceDiscReqPDU);
count = count+1;

% Decode the received BLE waveform and retrieve the application data.
receivedPDU = helperBLEDecodeData(bleWaveform);

% Decode the received ATT PDU and generate response PDU, if applicable.
[attServerRespPDU, serviceDiscReqCfg, gattServer] = receiveData(gattServer, receivedPDU);

fprintf("Received service discovery request at the server:\n")
serviceDiscReqCfg

% Transmit the application response data (|attServerRespPDU|) to the client
% through PHY.
[bleWaveform, pcapPackets{count}] = helperBLETransmitData(attServerRespPDU);
count = count+1;

% Decode the received BLE waveform and retrieve the application data.
receivedPDU = helperBLEDecodeData(bleWaveform);

% Decode received ATT PDU and generate response PDU, if applicable.
[~, serviceDiscRespCfg] = receiveData(gattClient, receivedPDU);
gattClient.StartHandle = serviceDiscRespCfg.StartHandle;
gattClient.EndHandle = serviceDiscRespCfg.EndHandle;

% Expected response from the server: |'Read by group type response'| or
% |'Error response'|.
if strcmp(serviceDiscRespCfg.Opcode, 'Error response')
    fprintf("Received error response at the client:\n")
    serviceDiscRespCfg
    serviceDiscRespMsg = ['Error response(''' serviceDiscRespCfg.ErrorMessage ''')'];
else
    fprintf("Received service discovery response at the client:\n")
    serviceDiscRespCfg
    service = helperBluetoothID.getBluetoothName(serviceDiscRespCfg.AttributeValue);
    serviceDiscRespMsg = ['Service discovery response(''' service ''')'];
end

% Configure a GATT client to discover all the available characteristics at
% the server.
gattClient.SubProcedure = 'Discover all characteristics of service';
chrsticDiscReqPDU = generateATTPDU(gattClient);

% Transmit the application data (|chrsticDiscReqPDU|) to the server through
% PHY.
[bleWaveform, pcapPackets{count}] = helperBLETransmitData(chrsticDiscReqPDU);
count = count+1;

% Decode the received BLE waveform and retrieve the application data.
receivedPDU = helperBLEDecodeData(bleWaveform);

% Decode received ATT PDU and generate response PDU, if applicable.
[chrsticDiscRespPDU, chrsticDiscReqCfg, gattServer] = receiveData(gattServer, receivedPDU);

fprintf("Received characteristic discovery request at the server:\n")
chrsticDiscReqCfg

% Transmit the application response data (|chrsticDiscRespPDU|) to the
% client through PHY.
[bleWaveform, pcapPackets{count}] = helperBLETransmitData(chrsticDiscRespPDU);
count = count+1;

% Decode the received BLE waveform and retrieve the application data.
receivedPDU = helperBLEDecodeData(bleWaveform);

% Decode received ATT PDU and generate response PDU, if applicable.
[~, chrsticDiscRespCfg] = receiveData(gattClient, receivedPDU);

% Expected response from the server: |'Read by type response'| or |'Error
% response'|.
if strcmp(chrsticDiscRespCfg.Opcode, 'Error response')
    fprintf("Received error response at the client:\n")
    chrsticDiscRespCfg
    chrsticDescRespMsg = ['Error response(''' chrsticDiscRespCfg.ErrorMessage ''')'];
else
    fprintf("Received characteristic discovery response at the client:\n")
    attributeValueCfg = helperBLEDecodeAttributeValue(...
        chrsticDiscRespCfg.AttributeValue, 'Characteristic');
    attributeValueCfg
    chrsticDescRespMsg = ['Characteristic discovery response(''' attributeValueCfg.CharacteristicType ''')'];
end

% Configure a GATT client to discover all the available characteristic
% descriptors at the server.
gattClient.SubProcedure = 'Discover all descriptors';
gattClient.StartHandle = dec2hex(hex2dec(chrsticDiscRespCfg.AttributeHandle)+1, 4);
chrsticDescDiscReqPDU = generateATTPDU(gattClient);

% Transmit the application data (|chrsticDescDiscReqPDU|) to the client
% through PHY.
[bleWaveform, pcapPackets{count}] = helperBLETransmitData(chrsticDescDiscReqPDU);
count = count+1;

% Decode the received BLE waveform and retrieve the application data.
receivedPDU = helperBLEDecodeData(bleWaveform);

% Decode received ATT PDU and generate response PDU, if applicable.
[chrsticDescDiscRespPDU, chrsticDescDiscReqCfg, gattServer] = receiveData(gattServer, receivedPDU);

fprintf("Received characteristic descriptor discovery request at the server:\n")
chrsticDescDiscReqCfg

% Transmit the application response data (|chrsticDescDiscRespPDU|) to the
% client through PHY.
[bleWaveform, pcapPackets{count}] = helperBLETransmitData(chrsticDescDiscRespPDU);
count = count+1;

% Decode the received BLE waveform and retrieve the application data.
receivedPDU = helperBLEDecodeData(bleWaveform);

% Decode received ATT PDU and generate response PDU, if applicable.
[~, chrsticDescDiscRespCfg] = receiveData(gattClient, receivedPDU);

% Expected response from the server: |'Information response'| or |'Error
% response'|.
if strcmp(chrsticDescDiscRespCfg.Opcode, 'Error response')
    fprintf("Received error response at the client:\n")
    chrsticDescDiscRespCfg
    chrsticDescDiscRespMsg = ['Error response(''' chrsticDescDiscRespCfg.ErrorMessage ''')'];
else
    fprintf("Received characteristic descriptor discovery response at the client:\n")
    chrsticDescDiscRespCfg
    descriptor = helperBluetoothID.getBluetoothName(chrsticDescDiscRespCfg.AttributeType);
    chrsticDescDiscRespMsg = ['Characteristic descriptor discovery response(''' descriptor ''')'];
end

% Configure a GATT client to enable the notifications of Heart rate
% measurement characteristic.
gattClient.SubProcedure = 'Write characteristic value';
gattClient.AttributeHandle = chrsticDescDiscRespCfg.AttributeHandle;
gattClient.AttributeValue = '0100';
enableNotificationReqPDU = generateATTPDU(gattClient);

% Transmit the application data (|enableNotificationReqPDU|) to the client
% through PHY.
[bleWaveform, pcapPackets{count}] = helperBLETransmitData(enableNotificationReqPDU);
count = count+1;

% Decode the received BLE waveform and retrieve the application data.
receivedPDU = helperBLEDecodeData(bleWaveform);

% Decode received ATT PDU and generate response PDU, if applicable.
[enableNotificationRespPDU, enableNotificationReqCfg, gattServer] = receiveData(gattServer, receivedPDU);

fprintf("Received enable notification request at the server:\n")
enableNotificationReqCfg

% Transmit the application response data (|enableNotificationRespPDU|) to
% the client through PHY.
[bleWaveform, pcapPackets{count}] = helperBLETransmitData(enableNotificationRespPDU);
count = count+1;

% Decode the received BLE waveform and retrieve the application data.
receivedPDU = helperBLEDecodeData(bleWaveform);

% Decode received ATT PDU and generate response PDU, if applicable.
[~, enableNotificationRespCfg] = receiveData(gattClient, receivedPDU);

% Expected response from the server: |'Write response'| or |'Error
% response'|.
if strcmp(enableNotificationRespCfg.Opcode, 'Error response')
    fprintf("Received error response at the client:\n")
    enableNotificationRespCfg
    enableNotificRespMsg = ['Error response(''' enableNotificationRespCfg.ErrorMessage ''')'];
else
    fprintf("Received enable notification response at the client:\n")
    enableNotificationRespCfg
    enableNotificRespMsg = 'Notifications enabled(''Heart rate measurement '')';
end

% Reset the random number generator seed.
rng default

% Measure heart rate value using sensor (generate a random number for heart
% rate measurement value).
heartRateMeasurementValue = randi([65 95]);

% Notify the heart rate measurement.
[gattServer, notificationPDU] = notifyHeartRateMeasurement(gattServer, ...
    heartRateMeasurementValue);

% Transmit the application data (|notificationPDU|) to the client through
% PHY.
[bleWaveform, pcapPackets{count}] = helperBLETransmitData(notificationPDU);
count = count+1;

% Decode the received BLE waveform and retrieve the application data.
receivedPDU = helperBLEDecodeData(bleWaveform);

% Decode received ATT PDU and generate response PDU, if applicable.
[~, notificationCfg] = receiveData(gattClient, receivedPDU);

fprintf("Received notification at the client:\n")

% Decode the received heart rate measurement characteristic value.
heartRateCharacteristicValue = helperBLEDecodeAttributeValue(...
    notificationCfg.AttributeValue, 'Heart rate measurement');
heartRateCharacteristicValue

heartRateMeasurementValue = heartRateCharacteristicValue.HeartRateValue;

% Visualize the BLE GATT Client-Server model.
helperBLEVisualizeHRPFrame(serviceDiscRespMsg, chrsticDescRespMsg, ...
    chrsticDescDiscRespMsg, enableNotificRespMsg, heartRateMeasurementValue);

% Create the BLE PCAP Writer file object
pcapObj = blePCAPWriter("FileName", "bleHRP");

timestamp = 124800; % timestamp (in microseconds)

% Write all the LL PDUs to the PCAP file
for idx = 1:numel(pcapPackets)
    write(pcapObj, pcapPackets{idx}, timestamp, "PacketFormat", "bits");
end

% Clear the object
clear pcapObj;

fprintf("Open generated pcap file 'bleHRP.pcap' in a protocol analyzer to view the generated frames.\n")