async private Task LoadMessagesFromServer() //Function to create a Json object and send to server using a lambda function
{
try
{
UserInfoItem message = new UserInfoItem { Item = new MessageLst { ToFrom = Helpers.Settings.ToFromArn, Time = Constants.date.ToString("yyyy-MM-dd HH:mm:ss:ffff") } }; //Helpers.Settings.EndpointArnSetting
UserInfoJson messageJson = new UserInfoJson { operation = "read", tableName = "Message", payload = message };
string args = JsonConvert.SerializeObject(messageJson);
var ir = new InvokeRequest()
{
FunctionName = Constants.AWSLambdaID,
PayloadStream = AWSSDKUtils.GenerateMemoryStreamFromString(args),
InvocationType = InvocationType.RequestResponse
};
InvokeResponse resp = await AmazonUtils.LambdaClient.InvokeAsync(ir);
resp.Payload.Position = 0;
var sr = new StreamReader(resp.Payload);
var myStr = sr.ReadToEnd();
try
{
System.Diagnostics.Debug.WriteLine("Returned Messages : " + myStr);
var response = JsonConvert.DeserializeObject<ConversationResponse>(myStr);
if (response.Success == "true")
{
var messages = response.MessageList;
messagesFromServer(messages);
}
}
catch (Exception e)
{
}
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine("Error:" + e);
}
}
/**
* Generates or updates user account when the page is accessed or information is changed.
* Sends request to server which updates the user table.
*/
async private Task Handshake()
{
try
{
string operation;
if (!Helpers.Settings.HandShakeDone)
{
operation = "create";
Helpers.Settings.HandShakeDone = true;
}
else
{
operation = "update";
}
UserInfoItem message;
if (Helpers.Settings.IsVolunteer)
{
if(Helpers.Settings.ChatActiveSetting){
message = new UserInfoItem { Item = new UserInfo { Latitude = latitude, Longitude = longitude, Nickname = Helpers.Settings.UsernameSetting, Arn = Helpers.Settings.EndpointArnSetting, Available = true } };
}else{
message = new UserInfoItem { Item = new UserInfo { Latitude = latitude, Longitude = longitude, Nickname = Helpers.Settings.UsernameSetting, Arn = Helpers.Settings.EndpointArnSetting, Available = false } };
}
}
else{
message = new UserInfoItem { Item = new UserInfo { Latitude = latitude, Longitude = longitude, Nickname = this.nameEntry.Text, Arn = Helpers.Settings.EndpointArnSetting, Available = true } }; //Helpers.Settings.EndpointArnSetting
}
Helpers.Settings.UsernameSetting = this.nameEntry.Text;
UserInfoJson messageJson = new UserInfoJson { operation = operation, tableName = "User", payload = message };
string args = JsonConvert.SerializeObject(messageJson);
var ir = new InvokeRequest()
{
FunctionName = Constants.AWSLambdaID,
PayloadStream = AWSSDKUtils.GenerateMemoryStreamFromString(args),
InvocationType = InvocationType.RequestResponse
};
InvokeResponse resp = await AmazonUtils.LambdaClient.InvokeAsync(ir);
resp.Payload.Position = 0;
var sr = new StreamReader(resp.Payload);
var myStr = sr.ReadToEnd();
// System.Diagnostics.Debug.WriteLine("Status code: " + resp.StatusCode);
// System.Diagnostics.Debug.WriteLine("Response content: " + myStr);
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine("Error:" + e);
}
}
/**
* Called when the end conversation button is pressed by the user
* Generates request to server, which then terminates the conversation
* for both users.
*/
async private Task terminateConversation()
{
//ID = is from ToFrom Field
UserInfoItem message = new UserInfoItem { Item = new UserInfo { ID = Helpers.Settings.ToFromArn } }; //Helpers.Settings.EndpointArnSetting
UserInfoJson messageJson = new UserInfoJson { operation = "stopConversation", tableName = "User", payload = message };
string args = JsonConvert.SerializeObject(messageJson);
System.Diagnostics.Debug.WriteLine("stopConversation: " + args);
var ir = new InvokeRequest()
{
FunctionName = Constants.AWSLambdaID,
PayloadStream = AWSSDKUtils.GenerateMemoryStreamFromString(args),
InvocationType = InvocationType.RequestResponse
};
InvokeResponse resp = await AmazonUtils.LambdaClient.InvokeAsync(ir);
resp.Payload.Position = 0;
var sr = new StreamReader(resp.Payload);
var myStr = sr.ReadToEnd();
System.Diagnostics.Debug.WriteLine("stopConversation : " + myStr);
Helpers.Settings.ToFromArn = "";
Constants.conv.name = "";
Constants.conv.id = "";
}
/**
* Queries the server for active conversations, called when the page is loaded
* if there exists an active conversation, returns conversation information to
* user and activates continue conversation option.
*/
async private Task queryServerActiveConversation()
{
UserInfoItem message = new UserInfoItem { Item = new UserInfo {} }; //Helpers.Settings.EndpointArnSetting
UserInfoJson messageJson = new UserInfoJson { operation = "currentConversations", tableName = "User", payload = message };
string args = JsonConvert.SerializeObject(messageJson);
System.Diagnostics.Debug.WriteLine("currentConversation: " + args);
var ir = new InvokeRequest()
{
FunctionName = Constants.AWSLambdaID,
PayloadStream = AWSSDKUtils.GenerateMemoryStreamFromString(args),
InvocationType = InvocationType.RequestResponse
};
InvokeResponse resp = await AmazonUtils.LambdaClient.InvokeAsync(ir);
resp.Payload.Position = 0;
var sr = new StreamReader(resp.Payload);
var myStr = sr.ReadToEnd();
Boolean failure = false;
try
{
var response = JsonConvert.DeserializeObject<ConversationResponse>(myStr);
System.Diagnostics.Debug.WriteLine("currentConversations : " + myStr);
if (response.Success == "true")
{
if (response.Conversations[0].ID != Helpers.Settings.ToFromArn)
{
Constants.conv.name = response.Conversations[0].Nickname;
Constants.conv.id = response.Conversations[0].ID;
Helpers.Settings.ToFromArn = response.Conversations[0].ID;
Constants.conv.msgs.Clear();
}
else
{
Constants.conv.name = response.Conversations[0].Nickname;
Constants.conv.id = response.Conversations[0].ID;
}
continueConversationPath();
}
else if (response.Success == "false")
{
Helpers.Settings.ToFromArn = "";
startConversationPath();
}
else
{
await DisplayAlert("Error", "No active conversations.", "OK");
}
}
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine(e);
failure = true;
}
if (failure) { await DisplayAlert("Error", "No active conversations", "OK"); }
}
/**
* Called when the start button is tapped, generates request to server
* checks response and either actives enter conversation mode or prompts
* user with failed to start message.
*/
async private Task initiateConversation(){
UserInfoItem message = new UserInfoItem { Item = new UserInfo { } }; //Helpers.Settings.EndpointArnSetting
UserInfoJson messageJson = new UserInfoJson { operation = "newConversation", tableName = "User", payload = message };
string args = JsonConvert.SerializeObject(messageJson);
System.Diagnostics.Debug.WriteLine("newConversation: " + args);
var ir = new InvokeRequest()
{
FunctionName = Constants.AWSLambdaID,
PayloadStream = AWSSDKUtils.GenerateMemoryStreamFromString(args),
InvocationType = InvocationType.RequestResponse
};
InvokeResponse resp = await AmazonUtils.LambdaClient.InvokeAsync(ir);
resp.Payload.Position = 0;
var sr = new StreamReader(resp.Payload);
var myStr = sr.ReadToEnd();
Boolean failure = false;
try {
System.Diagnostics.Debug.WriteLine("newConversations : " + myStr);
var response = JsonConvert.DeserializeObject<ConversationResponse>(myStr);
if (response.Success == "true")
{
Constants.conv.name = response.Nickname;
Constants.conv.id = response.ID;
Constants.conv.msgs.Clear();
Helpers.Settings.ToFromArn = response.ID;
continueConversationPath();
var stack = Navigation.NavigationStack;
if (stack[stack.Count - 1].GetType() != typeof(ChatPage))
await Navigation.PushAsync(new ChatPage(), false);
}
else
{
await DisplayAlert("Error", "No available volunteers, please try again later.", "OK");
}
}
catch(Exception e)
{
failure = true;
}
if (failure)
{
await DisplayAlert("Error", "No available volunteers, please try again later.", "OK");
}
}