package comp.pos.main;

import java.util.ArrayList;
import java.util.HashMap;

import comp.pos.client.A4Client;
import comp.pos.server.*;
import comp.pos.server.A4POSServer.*;

/*
* Main class which launches server and calls clients to run program
*/
public class Main {

// Main method for program execution
public static void main(String[] args) {
A4Server server = A4Server.getInstance();
HashMap<Integer, String> transactionIDs = new HashMap<Integer, String>();
// Get commands in a loop
while (true) {
String cmd = A4Client.nextCommand();
if (cmd == null)
break;
String[] params = cmd.split(",");
int client = Integer.parseInt(params[0]);
if (params.length >= 3) {
long time = Long.parseLong(params[2]);
// Process purchase command
if (params[1].equals("PURCHASE")) {
String transactionID = server.createTransaction(TransactionType.PURCHASE, time, client);
if (transactionID == null) {
System.out.println("Error - Could not create PURCHASE transaction");
} else {
transactionIDs.put(client, transactionID);
System.out.println("Successfully created PURCHASE transaction " + transactionID);
}
// Process backorder command
} else if (params[1].equals("BACKORDER")) {
String transactionID = server.createTransaction(TransactionType.BACKORDER, time, client);
if (transactionID == null) {
System.out.println("Error - Could not create BACKORDER transaction");
} else {
transactionIDs.put(client, transactionID);
System.out.println("Successfully created BACKORDER transaction " + transactionID);
}
// Process return command
} else if (params[1].equals("RETURN")) {
String transactionID = server.createTransaction(TransactionType.RETURN, time, client);
if (transactionID == null) {
System.out.println("Error - Could not create RETURN transaction");
} else {
transactionIDs.put(client, transactionID);
System.out.println("Successfully created RETURN transaction " + transactionID);
}
// Process add item to transaction command
} else if (params[1].equals("ADD")) {
if (params.length == 4 && transactionIDs.containsKey(client)) {
String itemID = params[3];
String transactionID = transactionIDs.get(client);
String result = server.addItemToTransaction(transactionID, itemID, 1);
if (result != null) {
System.out.println("Error - " + result);
} else {
System.out.println("Successfully added " + itemID + " to transaction " + transactionID);
System.out.println("Current transaction:\n" + server.toString(transactionID));
}
} else {
System.out.println("Error - Could not add to transaction");
}
// Process complete transaction command
} else if (params[1].equals("COMPLETE")) {
if (transactionIDs.containsKey(client)) {
String transactionID = transactionIDs.get(client);
String result = server.completeTransaction(transactionID);
if (result != null) {
System.out.println("Error - " + result);
} else {
System.out.println("Successfully completed transaction " + transactionID);
System.out.println("Current transaction:\n" + server.toString(transactionID));
transactionIDs.remove(client);
}
} else {
System.out.println("Error - Could not complete transaction");
}
// Process search inventory command
} else if (params[1].equals("SEARCH")) {
if (params.length == 4) {
String pattern = params[3];
String iteratorID = server.search(pattern, ItemField.CODE);
int count = 0;
while (server.next(iteratorID)) {
count++;
if (count == 1)
System.out.println("Results:");
String itemID = server.queryMatch(iteratorID, ItemField.CODE);
String itemDescription = server.queryMatch(iteratorID, ItemField.DESCRIPTION);
System.out.println(itemID + " - " + itemDescription);
}
if (count == 0)
System.out.println("No items found found");
} else {
System.out.println("Error - Could not search transactions");
}
// Process summary of transactions command
} else if (params[1].equals("SUMMARY")) {
if (transactionIDs.containsKey(client)) {
String transactionID = transactionIDs.get(client);
String result = server.toString(transactionID);
if (result == null) {
System.out.println("Error - cannot summarize current transaction");
} else {
System.out.println(result);
}
} else {
ArrayList<String> clientTransactionIDs = server.getClientTransactions(client);
if (clientTransactionIDs.isEmpty()) {
System.out.println("No transactions found");
} else {
for (int i = 0; i < clientTransactionIDs.size(); i++) {
String transactionID = clientTransactionIDs.get(i);
String result = server.toString(transactionID);
if (result == null) {
System.out.println("Error - cannot summarize current transaction");
} else {
System.out.println(result);
}
}
}
}

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