Datastream bug fixes w/ not recognizing bytes

j3270/src/main/java/haus/nightmare/j3270/J3270App.java

@@ -1070,8 +1070,47 @@ public class J3270App extends JFrame implements ConnectionListener, ScreenUpdate
         }
     }
 
-    // ========== Main ==========
+    private static void applyProxyUrl(ConnectionConfig config, String proxyUrl) {
+        if (config == null || proxyUrl == null || proxyUrl.trim().isEmpty()) return;
+        try {
+            java.net.URI uri = new java.net.URI(proxyUrl.trim());
+            String scheme = uri.getScheme() != null ? uri.getScheme().toLowerCase() : "http";
+            ConnectionConfig.ProxyType pType;
+            int pPort;
+            if (scheme.equals("http") || scheme.equals("https")) {
+                pType = ConnectionConfig.ProxyType.HTTP;
+                pPort = uri.getPort() > 0 ? uri.getPort() : 8080;
+            } else if (scheme.equals("socks4") || scheme.equals("socks4a")) {
+                pType = ConnectionConfig.ProxyType.SOCKS4;
+                pPort = uri.getPort() > 0 ? uri.getPort() : 1080;
+            } else if (scheme.equals("socks5") || scheme.equals("socks")) {
+                pType = ConnectionConfig.ProxyType.SOCKS5;
+                pPort = uri.getPort() > 0 ? uri.getPort() : 1080;
+            } else {
+                return;
+            }
+            String pHost = uri.getHost();
+            String pUser = null;
+            String pPass = null;
+            String userInfo = uri.getUserInfo();
+            if (userInfo != null) {
+                int colon = userInfo.indexOf(':');
+                if (colon >= 0) {
+                    pUser = userInfo.substring(0, colon);
+                    pPass = userInfo.substring(colon + 1);
+                } else {
+                    pUser = userInfo;
+                }
+            }
+            if (pHost != null && !pHost.isEmpty()) {
+                config.setProxy(pType, pHost, pPort, pUser, pPass);
+            }
+        } catch (Exception e) {
+            log.warning("Failed to parse CLI proxy URL: " + proxyUrl);
+        }
+    }
 
+    // ========== Main ==========
 
     public static void main(String[] args) {
         boolean debug = false;
@@ -1081,6 +1120,8 @@ public class J3270App extends JFrame implements ConnectionListener, ScreenUpdate
         Boolean cliAutoSysUnlock = null;
         GraphicsMode cliGraphicsMode = null;
         String configFile = null;
+        String cliProxyUrl = null;
+        String cliProfileName = null;
 
         java.util.List<String> remainingArgs = new java.util.ArrayList<>();
         for (int i = 0; i < args.length; i++) {
@@ -1107,6 +1148,14 @@ public class J3270App extends JFrame implements ConnectionListener, ScreenUpdate
                 cliGraphicsMode = GraphicsMode.NONE;
             } else if (("-c".equals(arg) || "--config".equals(arg)) && i + 1 < args.length) {
                 configFile = args[++i];
+            } else if (arg.startsWith("--proxy=") || arg.startsWith("-proxy=")) {
+                cliProxyUrl = arg.substring(arg.indexOf('=') + 1).trim();
+            } else if (("--proxy".equals(arg) || "-proxy".equals(arg)) && i + 1 < args.length && !args[i + 1].startsWith("-")) {
+                cliProxyUrl = args[++i].trim();
+            } else if (arg.startsWith("--profile=")) {
+                cliProfileName = arg.substring(arg.indexOf('=') + 1).trim();
+            } else if ("--profile".equals(arg) && i + 1 < args.length && !args[i + 1].startsWith("-")) {
+                cliProfileName = args[++i].trim();
             } else if (arg.startsWith("-")) {
                 System.err.println("Unknown option: " + arg);
             } else {
@@ -1143,11 +1192,33 @@ public class J3270App extends JFrame implements ConnectionListener, ScreenUpdate
         final Boolean finalTn3270e = cliTn3270e;
         final Boolean finalAutoSysUnlock = cliAutoSysUnlock;
         final GraphicsMode finalGraphicsMode = cliGraphicsMode;
+        final String finalProxyUrl = cliProxyUrl;
+        final String finalProfileName = cliProfileName;
 
         SwingUtilities.invokeLater(() -> {
             J3270App app = new J3270App();
             app.setVisible(true);
 
+            if (finalProfileName != null) {
+                haus.nightmare.j3270.storage.SavedHost profile = haus.nightmare.j3270.storage.HostStorage.findByName(finalProfileName);
+                if (profile == null) {
+                    profile = haus.nightmare.j3270.storage.HostStorage.findById(finalProfileName);
+                }
+                if (profile != null) {
+                    ConnectionConfig config = profile.toConnectionConfig();
+                    if (finalTls) config.setUseTls(true);
+                    if (finalNoVerify) config.setTlsVerifyCert(false);
+                    if (finalTn3270e != null) config.setTn3270eEnabled(finalTn3270e);
+                    if (finalAutoSysUnlock != null) config.setAutoSysUnlock(finalAutoSysUnlock);
+                    if (finalGraphicsMode != null) config.setGraphicsMode(finalGraphicsMode);
+                    if (finalProxyUrl != null) applyProxyUrl(config, finalProxyUrl);
+                    app.connect(config);
+                    return;
+                } else {
+                    System.err.println("Profile not found: " + finalProfileName);
+                }
+            }
+
             if (!remainingArgs.isEmpty()) {
                 String hostArg = remainingArgs.get(0);
                 int port = finalTls ? 992 : 23;
@@ -1188,6 +1259,9 @@ public class J3270App extends JFrame implements ConnectionListener, ScreenUpdate
                 } else {
                     config.setGraphicsMode(haus.nightmare.j3270.config.Settings.getGraphicsMode());
                 }
+                if (finalProxyUrl != null) {
+                    applyProxyUrl(config, finalProxyUrl);
+                }
                 app.connect(config);
             } else {
                 haus.nightmare.j3270.config.Settings.StartupBehavior behavior = haus.nightmare.j3270.config.Settings
@@ -1197,6 +1271,17 @@ public class J3270App extends JFrame implements ConnectionListener, ScreenUpdate
                         SwingUtilities.invokeLater(app::showConnectDialog);
                         break;
                     case AUTO_CONNECT:
+                        haus.nightmare.j3270.storage.SavedHost autoHost = haus.nightmare.j3270.storage.HostStorage.getAutoConnectHost();
+                        if (autoHost != null) {
+                            ConnectionConfig config = autoHost.toConnectionConfig();
+                            if (finalTls) config.setUseTls(true);
+                            if (finalNoVerify) config.setTlsVerifyCert(false);
+                            if (finalTn3270e != null) config.setTn3270eEnabled(finalTn3270e);
+                            if (finalAutoSysUnlock != null) config.setAutoSysUnlock(finalAutoSysUnlock);
+                            if (finalGraphicsMode != null) config.setGraphicsMode(finalGraphicsMode);
+                            if (finalProxyUrl != null) applyProxyUrl(config, finalProxyUrl);
+                            app.connect(config);
+                        } else {
                             String host = haus.nightmare.j3270.config.Settings.getAutoConnectHost();
                             int port = haus.nightmare.j3270.config.Settings.getAutoConnectPort();
                             boolean tls = haus.nightmare.j3270.config.Settings.getAutoConnectTls();
@@ -1214,10 +1299,14 @@ public class J3270App extends JFrame implements ConnectionListener, ScreenUpdate
                                 } else {
                                     config.setGraphicsMode(haus.nightmare.j3270.config.Settings.getGraphicsMode());
                                 }
+                                if (finalProxyUrl != null) {
+                                    applyProxyUrl(config, finalProxyUrl);
+                                }
                                 app.connect(config);
                             } else {
                                 SwingUtilities.invokeLater(app::showConnectDialog);
                             }
+                        }
                         break;
                     case DO_NOTHING:
                     default:

j3270/src/main/java/haus/nightmare/j3270/storage/HostStorage.java

@@ -0,0 +1,434 @@
+package haus.nightmare.j3270.storage;
+
+import java.util.*;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import java.util.prefs.Preferences;
+
+/**
+ * Storage manager for saved host profiles, maintaining 1:1 format compatibility with a3270.
+ * Persists profiles in Java user preferences with JSON serialization.
+ */
+public class HostStorage {
+
+    private static final Logger log = Logger.getLogger(HostStorage.class.getName());
+    private static final Preferences prefs = Preferences.userNodeForPackage(HostStorage.class);
+    public static final String KEY_SAVED_HOSTS = "saved_hosts";
+
+    public static synchronized List<SavedHost> getSavedHosts() {
+        String jsonStr = prefs.get(KEY_SAVED_HOSTS, null);
+        if (jsonStr == null || jsonStr.trim().isEmpty()) {
+            return new ArrayList<>();
+        }
+        try {
+            return parseHostsJson(jsonStr);
+        } catch (Exception e) {
+            log.log(Level.WARNING, "Failed to parse saved hosts JSON", e);
+            return new ArrayList<>();
+        }
+    }
+
+    public static synchronized void saveHost(SavedHost host) {
+        if (host == null) return;
+        List<SavedHost> current = new ArrayList<>(getSavedHosts());
+        int index = -1;
+        for (int i = 0; i < current.size(); i++) {
+            if (Objects.equals(current.get(i).getId(), host.getId())) {
+                index = i;
+                break;
+            }
+        }
+
+        // If this host is set to autoConnect, clear autoConnect on all others
+        SavedHost hostToSave = host.copy();
+        if (hostToSave.isAutoConnect()) {
+            for (int i = 0; i < current.size(); i++) {
+                current.get(i).setAutoConnect(false);
+            }
+        }
+
+        if (index >= 0) {
+            current.set(index, hostToSave);
+        } else {
+            current.add(hostToSave);
+        }
+        saveAll(current);
+    }
+
+    public static synchronized void deleteHost(String hostId) {
+        if (hostId == null) return;
+        List<SavedHost> current = new ArrayList<>(getSavedHosts());
+        current.removeIf(h -> Objects.equals(h.getId(), hostId));
+        saveAll(current);
+    }
+
+    public static synchronized SavedHost getAutoConnectHost() {
+        for (SavedHost h : getSavedHosts()) {
+            if (h.isAutoConnect()) {
+                return h;
+            }
+        }
+        return null;
+    }
+
+    public static synchronized SavedHost findById(String id) {
+        if (id == null) return null;
+        for (SavedHost h : getSavedHosts()) {
+            if (id.equals(h.getId())) {
+                return h;
+            }
+        }
+        return null;
+    }
+
+    public static synchronized SavedHost findByName(String name) {
+        if (name == null) return null;
+        for (SavedHost h : getSavedHosts()) {
+            if (name.equalsIgnoreCase(h.getName())) {
+                return h;
+            }
+        }
+        return null;
+    }
+
+    public static synchronized void saveAll(List<SavedHost> hosts) {
+        if (hosts == null) return;
+        String json = serializeHostsJson(hosts);
+        prefs.put(KEY_SAVED_HOSTS, json);
+        try {
+            prefs.flush();
+        } catch (Exception ignored) {
+        }
+    }
+
+    public static synchronized void clearAll() {
+        prefs.remove(KEY_SAVED_HOSTS);
+        try {
+            prefs.flush();
+        } catch (Exception ignored) {
+        }
+    }
+
+    // ================= JSON Serialization =================
+
+    public static String serializeHostsJson(List<SavedHost> hosts) {
+        StringBuilder sb = new StringBuilder();
+        sb.append("[\n");
+        for (int i = 0; i < hosts.size(); i++) {
+            SavedHost h = hosts.get(i);
+            sb.append("  ").append(serializeHostJson(h));
+            if (i < hosts.size() - 1) {
+                sb.append(",");
+            }
+            sb.append("\n");
+        }
+        sb.append("]");
+        return sb.toString();
+    }
+
+    public static String serializeHostJson(SavedHost h) {
+        StringBuilder sb = new StringBuilder();
+        sb.append("{");
+        appendField(sb, "id", h.getId(), true);
+        appendField(sb, "name", h.getName(), true);
+        appendField(sb, "host", h.getHost(), true);
+        appendField(sb, "port", h.getPort(), true);
+        appendField(sb, "model", h.getModel(), true);
+        appendField(sb, "dynamicRows", h.getDynamicRows(), true);
+        appendField(sb, "dynamicCols", h.getDynamicCols(), true);
+        appendField(sb, "luName", h.getLuName(), true);
+        appendField(sb, "autoConnect", h.isAutoConnect(), true);
+        appendField(sb, "hostType", h.getHostType(), true);
+        appendField(sb, "useTls", h.isUseTls(), true);
+        appendField(sb, "tlsVerifyCert", h.isTlsVerifyCert(), true);
+        appendField(sb, "tn3270e", h.isTn3270e(), true);
+        appendField(sb, "graphicsMode", h.getGraphicsMode(), true);
+        appendField(sb, "codePage", h.getCodePage(), true);
+        appendField(sb, "proxyType", h.getProxyType(), true);
+        appendField(sb, "proxyHost", h.getProxyHost(), true);
+        appendField(sb, "proxyPort", h.getProxyPort(), true);
+        appendField(sb, "proxyUsername", h.getProxyUsername(), true);
+        appendField(sb, "proxyPassword", h.getProxyPassword(), false);
+        sb.append("}");
+        return sb.toString();
+    }
+
+    private static void appendField(StringBuilder sb, String key, String val, boolean comma) {
+        sb.append("\"").append(key).append("\":\"").append(escapeJson(val != null ? val : "")).append("\"");
+        if (comma) sb.append(",");
+    }
+
+    private static void appendField(StringBuilder sb, String key, int val, boolean comma) {
+        sb.append("\"").append(key).append("\":").append(val);
+        if (comma) sb.append(",");
+    }
+
+    private static void appendField(StringBuilder sb, String key, boolean val, boolean comma) {
+        sb.append("\"").append(key).append("\":").append(val);
+        if (comma) sb.append(",");
+    }
+
+    private static String escapeJson(String s) {
+        if (s == null) return "";
+        StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < s.length(); i++) {
+            char c = s.charAt(i);
+            switch (c) {
+                case '"': sb.append("\\\""); break;
+                case '\\': sb.append("\\\\"); break;
+                case '\b': sb.append("\\b"); break;
+                case '\f': sb.append("\\f"); break;
+                case '\n': sb.append("\\n"); break;
+                case '\r': sb.append("\\r"); break;
+                case '\t': sb.append("\\t"); break;
+                default:
+                    if (c < 32) {
+                        sb.append(String.format("\\u%04x", (int) c));
+                    } else {
+                        sb.append(c);
+                    }
+                    break;
+            }
+        }
+        return sb.toString();
+    }
+
+    // ================= JSON Deserialization =================
+
+    public static List<SavedHost> parseHostsJson(String json) {
+        List<SavedHost> list = new ArrayList<>();
+        if (json == null || json.trim().isEmpty()) return list;
+
+        SimpleJsonParser parser = new SimpleJsonParser(json);
+        Object root = parser.parseValue();
+        if (root instanceof List) {
+            for (Object item : (List<?>) root) {
+                if (item instanceof Map) {
+                    @SuppressWarnings("unchecked")
+                    Map<String, Object> map = (Map<String, Object>) item;
+                    list.add(fromMap(map));
+                }
+            }
+        } else if (root instanceof Map) {
+            @SuppressWarnings("unchecked")
+            Map<String, Object> map = (Map<String, Object>) root;
+            list.add(fromMap(map));
+        }
+        return list;
+    }
+
+    public static SavedHost fromMap(Map<String, Object> map) {
+        SavedHost h = new SavedHost();
+        if (map.containsKey("id")) h.setId(String.valueOf(map.get("id")));
+        if (map.containsKey("name")) h.setName(String.valueOf(map.get("name")));
+        if (map.containsKey("host")) h.setHost(String.valueOf(map.get("host")));
+        if (map.containsKey("port")) h.setPort(parseInt(map.get("port"), 23));
+        if (map.containsKey("model")) h.setModel(parseInt(map.get("model"), 4));
+        if (map.containsKey("dynamicRows")) h.setDynamicRows(parseInt(map.get("dynamicRows"), 62));
+        if (map.containsKey("dynamicCols")) h.setDynamicCols(parseInt(map.get("dynamicCols"), 160));
+        if (map.containsKey("luName")) h.setLuName(String.valueOf(map.get("luName")));
+        if (map.containsKey("autoConnect")) h.setAutoConnect(parseBool(map.get("autoConnect"), false));
+        if (map.containsKey("hostType")) h.setHostType(String.valueOf(map.get("hostType")));
+        if (map.containsKey("useTls")) h.setUseTls(parseBool(map.get("useTls"), false));
+        if (map.containsKey("tlsVerifyCert")) h.setTlsVerifyCert(parseBool(map.get("tlsVerifyCert"), true));
+        if (map.containsKey("tn3270e")) h.setTn3270e(parseBool(map.get("tn3270e"), true));
+        if (map.containsKey("graphicsMode")) {
+            String gm = String.valueOf(map.get("graphicsMode"));
+            if ("PROGRAMMED_SYMBOLS".equalsIgnoreCase(gm)) gm = "BOTH";
+            h.setGraphicsMode(gm);
+        }
+        if (map.containsKey("codePage")) h.setCodePage(String.valueOf(map.get("codePage")));
+        if (map.containsKey("proxyType")) h.setProxyType(String.valueOf(map.get("proxyType")));
+        if (map.containsKey("proxyHost")) h.setProxyHost(String.valueOf(map.get("proxyHost")));
+        if (map.containsKey("proxyPort")) h.setProxyPort(parseInt(map.get("proxyPort"), 0));
+        if (map.containsKey("proxyUsername")) h.setProxyUsername(String.valueOf(map.get("proxyUsername")));
+        if (map.containsKey("proxyPassword")) h.setProxyPassword(String.valueOf(map.get("proxyPassword")));
+        return h;
+    }
+
+    private static int parseInt(Object obj, int def) {
+        if (obj == null) return def;
+        if (obj instanceof Number) return ((Number) obj).intValue();
+        try {
+            return Integer.parseInt(String.valueOf(obj).trim());
+        } catch (Exception e) {
+            return def;
+        }
+    }
+
+    private static boolean parseBool(Object obj, boolean def) {
+        if (obj == null) return def;
+        if (obj instanceof Boolean) return (Boolean) obj;
+        return Boolean.parseBoolean(String.valueOf(obj).trim());
+    }
+
+    /**
+     * Minimal pure-Java JSON parser for nested Maps, Lists, Strings, Numbers, and Booleans.
+     */
+    static class SimpleJsonParser {
+        private final String src;
+        private int pos = 0;
+
+        SimpleJsonParser(String src) {
+            this.src = src;
+        }
+
+        Object parseValue() {
+            skipWhitespace();
+            if (pos >= src.length()) return null;
+            char c = src.charAt(pos);
+            if (c == '{') return parseObject();
+            if (c == '[') return parseArray();
+            if (c == '"') return parseString();
+            if (c == 't' || c == 'f') return parseBoolean();
+            if (c == 'n') return parseNull();
+            if (c == '-' || Character.isDigit(c)) return parseNumber();
+            throw new IllegalArgumentException("Unexpected char '" + c + "' at position " + pos);
+        }
+
+        private Map<String, Object> parseObject() {
+            match('{');
+            Map<String, Object> map = new LinkedHashMap<>();
+            skipWhitespace();
+            if (peek() == '}') {
+                pos++;
+                return map;
+            }
+            while (true) {
+                skipWhitespace();
+                String key = parseString();
+                skipWhitespace();
+                match(':');
+                Object val = parseValue();
+                map.put(key, val);
+                skipWhitespace();
+                char c = peek();
+                if (c == ',') {
+                    pos++;
+                } else if (c == '}') {
+                    pos++;
+                    break;
+                } else {
+                    break;
+                }
+            }
+            return map;
+        }
+
+        private List<Object> parseArray() {
+            match('[');
+            List<Object> list = new ArrayList<>();
+            skipWhitespace();
+            if (peek() == ']') {
+                pos++;
+                return list;
+            }
+            while (true) {
+                Object val = parseValue();
+                list.add(val);
+                skipWhitespace();
+                char c = peek();
+                if (c == ',') {
+                    pos++;
+                } else if (c == ']') {
+                    pos++;
+                    break;
+                } else {
+                    break;
+                }
+            }
+            return list;
+        }
+
+        private String parseString() {
+            match('"');
+            StringBuilder sb = new StringBuilder();
+            while (pos < src.length()) {
+                char c = src.charAt(pos++);
+                if (c == '"') {
+                    return sb.toString();
+                } else if (c == '\\') {
+                    if (pos >= src.length()) break;
+                    char esc = src.charAt(pos++);
+                    switch (esc) {
+                        case '"': sb.append('"'); break;
+                        case '\\': sb.append('\\'); break;
+                        case '/': sb.append('/'); break;
+                        case 'b': sb.append('\b'); break;
+                        case 'f': sb.append('\f'); break;
+                        case 'n': sb.append('\n'); break;
+                        case 'r': sb.append('\r'); break;
+                        case 't': sb.append('\t'); break;
+                        case 'u':
+                            if (pos + 4 <= src.length()) {
+                                String hex = src.substring(pos, pos + 4);
+                                pos += 4;
+                                try {
+                                    sb.append((char) Integer.parseInt(hex, 16));
+                                } catch (NumberFormatException e) {
+                                    sb.append("?");
+                                }
+                            }
+                            break;
+                        default:
+                            sb.append(esc);
+                            break;
+                    }
+                } else {
+                    sb.append(c);
+                }
+            }
+            return sb.toString();
+        }
+
+        private Boolean parseBoolean() {
+            if (src.startsWith("true", pos)) {
+                pos += 4;
+                return true;
+            } else if (src.startsWith("false", pos)) {
+                pos += 5;
+                return false;
+            }
+            throw new IllegalArgumentException("Expected boolean at " + pos);
+        }
+
+        private Object parseNull() {
+            if (src.startsWith("null", pos)) {
+                pos += 4;
+                return null;
+            }
+            throw new IllegalArgumentException("Expected null at " + pos);
+        }
+
+        private Number parseNumber() {
+            int start = pos;
+            if (src.charAt(pos) == '-') pos++;
+            while (pos < src.length() && (Character.isDigit(src.charAt(pos)) || src.charAt(pos) == '.' || src.charAt(pos) == 'e' || src.charAt(pos) == 'E' || src.charAt(pos) == '+' || src.charAt(pos) == '-')) {
+                pos++;
+            }
+            String numStr = src.substring(start, pos);
+            if (numStr.contains(".")) {
+                return Double.parseDouble(numStr);
+            }
+            return Long.parseLong(numStr);
+        }
+
+        private void skipWhitespace() {
+            while (pos < src.length() && Character.isWhitespace(src.charAt(pos))) {
+                pos++;
+            }
+        }
+
+        private char peek() {
+            return pos < src.length() ? src.charAt(pos) : '\0';
+        }
+
+        private void match(char expected) {
+            skipWhitespace();
+            if (pos >= src.length() || src.charAt(pos) != expected) {
+                throw new IllegalArgumentException("Expected '" + expected + "' at " + pos);
+            }
+            pos++;
+        }
+    }
+}

j3270/src/main/java/haus/nightmare/j3270/storage/SavedHost.java

@@ -0,0 +1,222 @@
+package haus.nightmare.j3270.storage;
+
+import haus.nightmare.lib3270j.ConnectionConfig;
+import haus.nightmare.lib3270j.TerminalModel;
+import haus.nightmare.lib3270j.graphics.GraphicsMode;
+
+import java.util.Objects;
+import java.util.UUID;
+
+/**
+ * Data model for a saved 3270 connection profile, matching the schema of a3270 SavedHost.
+ * Includes per-connection host, model, protocol, and proxy configuration.
+ */
+public class SavedHost {
+
+    private String id;
+    private String name;
+    private String host;
+    private int port;
+    private int model;
+    private int dynamicRows;
+    private int dynamicCols;
+    private String luName;
+    private boolean autoConnect;
+    private String hostType;
+    private boolean useTls;
+    private boolean tlsVerifyCert;
+    private boolean tn3270e;
+    private String graphicsMode;
+    private String codePage;
+
+    // Per-connection proxy configuration
+    private String proxyType;
+    private String proxyHost;
+    private int proxyPort;
+    private String proxyUsername;
+    private String proxyPassword;
+
+    public SavedHost() {
+        this.id = UUID.randomUUID().toString();
+        this.name = "Mainframe";
+        this.host = "127.0.0.1";
+        this.port = 23;
+        this.model = 4;
+        this.dynamicRows = 62;
+        this.dynamicCols = 160;
+        this.luName = "";
+        this.autoConnect = false;
+        this.hostType = "TSO";
+        this.useTls = false;
+        this.tlsVerifyCert = true;
+        this.tn3270e = true;
+        this.graphicsMode = "BOTH";
+        this.codePage = "037";
+        this.proxyType = "NONE";
+        this.proxyHost = "";
+        this.proxyPort = 0;
+        this.proxyUsername = "";
+        this.proxyPassword = "";
+    }
+
+    public SavedHost(String id, String name, String host, int port, int model,
+                     int dynamicRows, int dynamicCols, String luName, boolean autoConnect,
+                     String hostType, boolean useTls, boolean tlsVerifyCert, boolean tn3270e,
+                     String graphicsMode, String codePage, String proxyType, String proxyHost,
+                     int proxyPort, String proxyUsername, String proxyPassword) {
+        this.id = (id != null && !id.trim().isEmpty()) ? id : UUID.randomUUID().toString();
+        this.name = name != null ? name : "";
+        this.host = host != null ? host : "127.0.0.1";
+        this.port = port > 0 ? port : 23;
+        this.model = model;
+        this.dynamicRows = dynamicRows > 0 ? dynamicRows : 62;
+        this.dynamicCols = dynamicCols > 0 ? dynamicCols : 160;
+        this.luName = luName != null ? luName : "";
+        this.autoConnect = autoConnect;
+        this.hostType = hostType != null ? hostType : "TSO";
+        this.useTls = useTls;
+        this.tlsVerifyCert = tlsVerifyCert;
+        this.tn3270e = tn3270e;
+        this.graphicsMode = graphicsMode != null ? graphicsMode : "BOTH";
+        this.codePage = codePage != null ? codePage : "037";
+        this.proxyType = (proxyType != null && !proxyType.trim().isEmpty()) ? proxyType.toUpperCase() : "NONE";
+        this.proxyHost = proxyHost != null ? proxyHost : "";
+        this.proxyPort = proxyPort;
+        this.proxyUsername = proxyUsername != null ? proxyUsername : "";
+        this.proxyPassword = proxyPassword != null ? proxyPassword : "";
+    }
+
+    public SavedHost copy() {
+        return new SavedHost(id, name, host, port, model, dynamicRows, dynamicCols, luName,
+                autoConnect, hostType, useTls, tlsVerifyCert, tn3270e, graphicsMode, codePage,
+                proxyType, proxyHost, proxyPort, proxyUsername, proxyPassword);
+    }
+
+    /**
+     * Converts this saved host profile into an active ConnectionConfig.
+     */
+    public ConnectionConfig toConnectionConfig() {
+        TerminalModel tm;
+        if (model == 0) {
+            tm = TerminalModel.IBM_DYNAMIC;
+        } else {
+            try {
+                tm = TerminalModel.forModel(model, true);
+            } catch (Exception e) {
+                tm = TerminalModel.IBM_3279_4;
+            }
+        }
+
+        ConnectionConfig config = new ConnectionConfig(host, port, tm, useTls);
+        if (model == 0 || tm.isDynamic()) {
+            config.setDynamicDimensions(dynamicRows, dynamicCols);
+        }
+        if (luName != null && !luName.trim().isEmpty()) {
+            config.setLuName(luName.trim());
+        }
+        config.setTlsVerifyCert(tlsVerifyCert);
+        config.setTn3270eEnabled(tn3270e);
+        if (graphicsMode != null && !graphicsMode.isEmpty()) {
+            config.setGraphicsMode(GraphicsMode.fromString(graphicsMode));
+        }
+        if (codePage != null && !codePage.isEmpty()) {
+            config.setCodePage(codePage);
+        }
+
+        // Apply per-connection proxy if configured
+        if (proxyType != null && !proxyType.equalsIgnoreCase("NONE") && proxyHost != null && !proxyHost.trim().isEmpty()) {
+            try {
+                ConnectionConfig.ProxyType pt = ConnectionConfig.ProxyType.valueOf(proxyType.toUpperCase());
+                int pPort = proxyPort > 0 ? proxyPort : (pt == ConnectionConfig.ProxyType.HTTP ? 8080 : 1080);
+                config.setProxy(pt, proxyHost.trim(), pPort,
+                        (proxyUsername != null && !proxyUsername.trim().isEmpty()) ? proxyUsername.trim() : null,
+                        (proxyPassword != null && !proxyPassword.isEmpty()) ? proxyPassword : null);
+            } catch (IllegalArgumentException ignored) {
+            }
+        }
+        return config;
+    }
+
+    // Getters and Setters
+
+    public String getId() { return id; }
+    public void setId(String id) { this.id = id; }
+
+    public String getName() { return name; }
+    public void setName(String name) { this.name = name; }
+
+    public String getHost() { return host; }
+    public void setHost(String host) { this.host = host; }
+
+    public int getPort() { return port; }
+    public void setPort(int port) { this.port = port; }
+
+    public int getModel() { return model; }
+    public void setModel(int model) { this.model = model; }
+
+    public int getDynamicRows() { return dynamicRows; }
+    public void setDynamicRows(int dynamicRows) { this.dynamicRows = dynamicRows; }
+
+    public int getDynamicCols() { return dynamicCols; }
+    public void setDynamicCols(int dynamicCols) { this.dynamicCols = dynamicCols; }
+
+    public String getLuName() { return luName; }
+    public void setLuName(String luName) { this.luName = luName; }
+
+    public boolean isAutoConnect() { return autoConnect; }
+    public void setAutoConnect(boolean autoConnect) { this.autoConnect = autoConnect; }
+
+    public String getHostType() { return hostType; }
+    public void setHostType(String hostType) { this.hostType = hostType; }
+
+    public boolean isUseTls() { return useTls; }
+    public void setUseTls(boolean useTls) { this.useTls = useTls; }
+
+    public boolean isTlsVerifyCert() { return tlsVerifyCert; }
+    public void setTlsVerifyCert(boolean tlsVerifyCert) { this.tlsVerifyCert = tlsVerifyCert; }
+
+    public boolean isTn3270e() { return tn3270e; }
+    public void setTn3270e(boolean tn3270e) { this.tn3270e = tn3270e; }
+
+    public String getGraphicsMode() { return graphicsMode; }
+    public void setGraphicsMode(String graphicsMode) { this.graphicsMode = graphicsMode; }
+
+    public String getCodePage() { return codePage; }
+    public void setCodePage(String codePage) { this.codePage = codePage; }
+
+    public String getProxyType() { return proxyType != null ? proxyType : "NONE"; }
+    public void setProxyType(String proxyType) { this.proxyType = (proxyType != null) ? proxyType.toUpperCase() : "NONE"; }
+
+    public String getProxyHost() { return proxyHost != null ? proxyHost : ""; }
+    public void setProxyHost(String proxyHost) { this.proxyHost = proxyHost; }
+
+    public int getProxyPort() { return proxyPort; }
+    public void setProxyPort(int proxyPort) { this.proxyPort = proxyPort; }
+
+    public String getProxyUsername() { return proxyUsername != null ? proxyUsername : ""; }
+    public void setProxyUsername(String proxyUsername) { this.proxyUsername = proxyUsername; }
+
+    public String getProxyPassword() { return proxyPassword != null ? proxyPassword : ""; }
+    public void setProxyPassword(String proxyPassword) { this.proxyPassword = proxyPassword; }
+
+    @Override
+    public String toString() {
+        if (name != null && !name.trim().isEmpty()) {
+            return name;
+        }
+        return host + (port > 0 ? ":" + port : "");
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        SavedHost savedHost = (SavedHost) o;
+        return Objects.equals(id, savedHost.id);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(id);
+    }
+}

j3270/src/main/java/haus/nightmare/j3270/ui/ConnectDialog.java

@@ -1,16 +1,30 @@
 package haus.nightmare.j3270.ui;
 
+import haus.nightmare.j3270.storage.HostStorage;
+import haus.nightmare.j3270.storage.SavedHost;
 import haus.nightmare.lib3270j.ConnectionConfig;
 import haus.nightmare.lib3270j.TerminalModel;
 
 import javax.swing.*;
+import javax.swing.border.TitledBorder;
 import java.awt.*;
+import java.util.List;
 
 /**
- * Connection dialog for entering host, port, model, and LU name.
+ * Connection dialog for entering host, port, model, LU name, and per-connection proxy configuration.
+ * Supports loading and saving host profiles matching the a3270 schema.
  */
 public class ConnectDialog extends JDialog {
 
+    private static final String NEW_PROFILE_LABEL = "<New / Custom Connection>";
+
+    // Profile selector
+    private JComboBox<Object> profileCombo;
+    private JButton saveProfileBtn;
+    private JButton deleteProfileBtn;
+    private String selectedProfileId = null;
+
+    // Connection parameters
     private JTextField hostField;
     private JTextField portField;
     private JComboBox<TerminalModel> modelCombo;
@@ -26,6 +40,14 @@ public class ConnectDialog extends JDialog {
     private JCheckBox tn3270eCheckBox;
     private JCheckBox keepAliveCheckBox;
     private JCheckBox autoReconnectCheckBox;
+
+    // Per-connection proxy configuration
+    private JComboBox<ConnectionConfig.ProxyType> proxyTypeCombo;
+    private JTextField proxyHostField;
+    private JTextField proxyPortField;
+    private JTextField proxyUserField;
+    private JPasswordField proxyPassField;
+
     private boolean confirmed;
     private ConnectionConfig result;
 
@@ -35,64 +57,114 @@ public class ConnectDialog extends JDialog {
         buildUI();
         pack();
         setLocationRelativeTo(parent);
-        setResizable(false);
+        setResizable(true);
     }
 
     private void buildUI() {
-        JPanel mainPanel = new JPanel(new GridBagLayout());
+        JPanel contentPanel = new JPanel(new GridBagLayout());
-        mainPanel.setBorder(BorderFactory.createEmptyBorder(16, 16, 16, 16));
+        contentPanel.setBorder(BorderFactory.createEmptyBorder(12, 14, 12, 14));
         GridBagConstraints gbc = new GridBagConstraints();
-        gbc.insets = new Insets(5, 6, 5, 6);
+        gbc.insets = new Insets(4, 5, 4, 5);
         gbc.fill = GridBagConstraints.HORIZONTAL;
 
         Font labelFont = ThemeManager.getUiFont();
 
-        // Host
+        int gridy = 0;
+
+        // 0. Profile Row
         gbc.gridx = 0;
-        gbc.gridy = 0;
+        gbc.gridy = gridy;
+        gbc.weightx = 0;
+        JLabel profileLabel = new JLabel("Profile:");
+        profileLabel.setFont(labelFont);
+        contentPanel.add(profileLabel, gbc);
+
+        gbc.gridx = 1;
+        gbc.weightx = 1.0;
+        JPanel profileBar = new JPanel(new BorderLayout(6, 0));
+        profileBar.setOpaque(false);
+
+        profileCombo = new JComboBox<>();
+        profileCombo.setFont(ThemeManager.getUiFont());
+        ThemeManager.styleComboBox(profileCombo);
+        refreshProfileCombo();
+        profileCombo.addActionListener(e -> onProfileSelectionChanged());
+        profileBar.add(profileCombo, BorderLayout.CENTER);
+
+        JPanel profileBtnBar = new JPanel(new FlowLayout(FlowLayout.RIGHT, 4, 0));
+        profileBtnBar.setOpaque(false);
+
+        saveProfileBtn = new JButton("Save Profile...");
+        ThemeManager.styleButton(saveProfileBtn, ThemeManager.ButtonVariant.DEFAULT);
+        saveProfileBtn.setFont(labelFont);
+        saveProfileBtn.addActionListener(e -> onSaveProfile());
+
+        deleteProfileBtn = new JButton("Delete");
+        ThemeManager.styleButton(deleteProfileBtn, ThemeManager.ButtonVariant.CANCEL);
+        deleteProfileBtn.setFont(labelFont);
+        deleteProfileBtn.setEnabled(false);
+        deleteProfileBtn.addActionListener(e -> onDeleteProfile());
+
+        profileBtnBar.add(saveProfileBtn);
+        profileBtnBar.add(deleteProfileBtn);
+        profileBar.add(profileBtnBar, BorderLayout.EAST);
+        contentPanel.add(profileBar, gbc);
+
+        gridy++;
+
+        // 1. Host
+        gbc.gridx = 0;
+        gbc.gridy = gridy;
+        gbc.weightx = 0;
         JLabel hostLabel = new JLabel("Host:");
         hostLabel.setFont(labelFont);
-        mainPanel.add(hostLabel, gbc);
+        contentPanel.add(hostLabel, gbc);
         gbc.gridx = 1;
         gbc.weightx = 1.0;
         hostField = createField(20);
-        mainPanel.add(hostField, gbc);
+        contentPanel.add(hostField, gbc);
 
-        // Port
+        gridy++;
+
+        // 2. Port
         gbc.gridx = 0;
-        gbc.gridy = 1;
+        gbc.gridy = gridy;
         gbc.weightx = 0;
         JLabel portLabel = new JLabel("Port:");
         portLabel.setFont(labelFont);
-        mainPanel.add(portLabel, gbc);
+        contentPanel.add(portLabel, gbc);
         gbc.gridx = 1;
         gbc.weightx = 1.0;
         portField = createField(6);
         portField.setText("23");
-        mainPanel.add(portField, gbc);
+        contentPanel.add(portField, gbc);
 
-        // Model
+        gridy++;
+
+        // 3. Model
         gbc.gridx = 0;
-        gbc.gridy = 2;
+        gbc.gridy = gridy;
         gbc.weightx = 0;
         JLabel modelLabel = new JLabel("Model:");
         modelLabel.setFont(labelFont);
-        mainPanel.add(modelLabel, gbc);
+        contentPanel.add(modelLabel, gbc);
         gbc.gridx = 1;
         gbc.weightx = 1.0;
         modelCombo = new JComboBox<>(TerminalModel.values());
         modelCombo.setSelectedItem(TerminalModel.IBM_3279_4);
         modelCombo.setFont(ThemeManager.getMonospacedUiFont());
         ThemeManager.styleComboBox(modelCombo);
-        mainPanel.add(modelCombo, gbc);
+        contentPanel.add(modelCombo, gbc);
 
-        // Dynamic Dimensions (shown when IBM-DYNAMIC is selected)
+        gridy++;
+
+        // 4. Dynamic Dimensions
         gbc.gridx = 0;
-        gbc.gridy = 3;
+        gbc.gridy = gridy;
         gbc.weightx = 0;
         dynamicDimLabel = new JLabel("Screen Size:");
         dynamicDimLabel.setFont(labelFont);
-        mainPanel.add(dynamicDimLabel, gbc);
+        contentPanel.add(dynamicDimLabel, gbc);
 
         gbc.gridx = 1;
         gbc.weightx = 1.0;
@@ -113,7 +185,7 @@ public class ConnectDialog extends JDialog {
         dynamicDimPanel.add(dynamicRowsSpinner);
         dynamicDimPanel.add(colsLabel);
         dynamicDimPanel.add(dynamicColsSpinner);
-        mainPanel.add(dynamicDimPanel, gbc);
+        contentPanel.add(dynamicDimPanel, gbc);
 
         Runnable updateDynamicVisibility = () -> {
             TerminalModel m = (TerminalModel) modelCombo.getSelectedItem();
@@ -125,40 +197,46 @@ public class ConnectDialog extends JDialog {
         modelCombo.addActionListener(e -> updateDynamicVisibility.run());
         updateDynamicVisibility.run();
 
-        // LU Name
+        gridy++;
+
+        // 5. LU Name
         gbc.gridx = 0;
-        gbc.gridy = 4;
+        gbc.gridy = gridy;
         gbc.weightx = 0;
         JLabel luLabel = new JLabel("LU Name:");
         luLabel.setFont(labelFont);
-        mainPanel.add(luLabel, gbc);
+        contentPanel.add(luLabel, gbc);
         gbc.gridx = 1;
         gbc.weightx = 1.0;
         luField = createField(12);
-        mainPanel.add(luField, gbc);
+        contentPanel.add(luField, gbc);
 
-        // Graphics Mode
+        gridy++;
+
+        // 6. Graphics Mode
         gbc.gridx = 0;
-        gbc.gridy = 5;
+        gbc.gridy = gridy;
         gbc.weightx = 0;
         JLabel graphicsLabel = new JLabel("Graphics:");
         graphicsLabel.setFont(labelFont);
-        mainPanel.add(graphicsLabel, gbc);
+        contentPanel.add(graphicsLabel, gbc);
         gbc.gridx = 1;
         gbc.weightx = 1.0;
         graphicsCombo = new JComboBox<>(haus.nightmare.lib3270j.graphics.GraphicsMode.values());
         graphicsCombo.setSelectedItem(haus.nightmare.j3270.config.Settings.getGraphicsMode());
         graphicsCombo.setFont(ThemeManager.getUiFont());
         ThemeManager.styleComboBox(graphicsCombo);
-        mainPanel.add(graphicsCombo, gbc);
+        contentPanel.add(graphicsCombo, gbc);
 
-        // Code Page
+        gridy++;
+
+        // 7. Code Page
         gbc.gridx = 0;
-        gbc.gridy = 6;
+        gbc.gridy = gridy;
         gbc.weightx = 0;
         JLabel cpLabel = new JLabel("Code Page:");
         cpLabel.setFont(labelFont);
-        mainPanel.add(cpLabel, gbc);
+        contentPanel.add(cpLabel, gbc);
         gbc.gridx = 1;
         gbc.weightx = 1.0;
         String[] commonCodePages = {
@@ -179,43 +257,44 @@ public class ConnectDialog extends JDialog {
             "1155 - Turkey (Turkish Latin-5 Euro \u20AC)",
             "905 - Turkey (Turkish Latin-3)",
             "420 - Arabic Bilingual",
-            "424 - Hebrew (with Lowercase)",
+            "424 - Hebrew (with Latin)",
-            "803 - Hebrew Old / Standard",
+            "803 - Hebrew Character Set",
-            "838 - Thai",
+            "838 - Thai Extended",
-            "1160 - Thai (Euro \u20AC)",
+            "1160 - Thai Euro \u20AC",
             "1025 - Cyrillic Multilingual",
             "1123 - Cyrillic Ukraine",
-            "1154 - Cyrillic Multilingual (Euro \u20AC)",
+            "1154 - Cyrillic Euro \u20AC",
-            "880 - Cyrillic Russian",
+            "880 - Cyrillic (Russian)",
             "1140 - US / Canada (Euro \u20AC)",
             "1141 - Germany / Austria (Euro \u20AC)",
+            "1142 - Denmark / Norway (Euro \u20AC)",
+            "1143 - Sweden / Finland (Euro \u20AC)",
+            "1144 - Italy (Euro \u20AC)",
+            "1145 - Spain / Latin America (Euro \u20AC)",
+            "1146 - United Kingdom (Euro \u20AC)",
+            "1147 - France (Euro \u20AC)",
             "1148 - International (Euro \u20AC)",
+            "1149 - Iceland (Euro \u20AC)",
             "930 - Japanese Katakana Mixed DBCS",
             "939 - Japanese Latin Mixed DBCS",
             "935 - Simplified Chinese Mixed DBCS",
-            "1388 - Simplified Chinese Extended Mixed DBCS",
             "937 - Traditional Chinese Mixed DBCS",
-            "1371 - Traditional Chinese Extended Mixed DBCS",
+            "1388 - Simplified Chinese Extended DBCS",
+            "1371 - Traditional Chinese Extended DBCS",
             "933 - Korean Mixed DBCS"
         };
         codePageCombo = new JComboBox<>(commonCodePages);
-        codePageCombo.setEditable(true);
+        codePageCombo.setFont(ThemeManager.getMonospacedUiFont());
-        String currentCp = haus.nightmare.j3270.config.Settings.getCodePage();
-        for (String item : commonCodePages) {
-            if (item.startsWith(currentCp + " ") || item.equals(currentCp)) {
-                codePageCombo.setSelectedItem(item);
-                break;
-            }
-        }
-        codePageCombo.setFont(ThemeManager.getUiFont());
         ThemeManager.styleComboBox(codePageCombo);
-        mainPanel.add(codePageCombo, gbc);
+        setInitialCodePage(haus.nightmare.j3270.config.Settings.getCodePage());
+        contentPanel.add(codePageCombo, gbc);
 
-        // TLS / SSL Checkbox
+        gridy++;
+
+        // 8. TLS Checkbox
         gbc.gridx = 1;
-        gbc.gridy = 7;
+        gbc.gridy = gridy;
-        gbc.weightx = 1.0;
+        tlsCheckBox = new JCheckBox("Use TLS / SSL Encryption");
-        tlsCheckBox = new JCheckBox("Enable TLS/SSL");
         ThemeManager.styleCheckBox(tlsCheckBox);
         tlsCheckBox.setFont(labelFont);
         tlsCheckBox.addActionListener(e -> {
@@ -228,46 +307,169 @@ public class ConnectDialog extends JDialog {
                 portField.setText("23");
             }
         });
-        mainPanel.add(tlsCheckBox, gbc);
+        contentPanel.add(tlsCheckBox, gbc);
 
-        // Verify Certificate Checkbox
+        gridy++;
+
+        // 9. Verify Cert Checkbox
         gbc.gridx = 1;
-        gbc.gridy = 8;
+        gbc.gridy = gridy;
         verifyCertCheckBox = new JCheckBox("Verify Server Certificate");
         ThemeManager.styleCheckBox(verifyCertCheckBox);
         verifyCertCheckBox.setFont(ThemeManager.getUiFont());
         verifyCertCheckBox.setSelected(true);
         verifyCertCheckBox.setEnabled(false);
-        mainPanel.add(verifyCertCheckBox, gbc);
+        contentPanel.add(verifyCertCheckBox, gbc);
 
-        // TN3270E Checkbox
+        gridy++;
+
+        // 10. TN3270E Checkbox
         gbc.gridx = 1;
-        gbc.gridy = 9;
+        gbc.gridy = gridy;
         tn3270eCheckBox = new JCheckBox("Enable TN3270E (Extended 3270)");
         ThemeManager.styleCheckBox(tn3270eCheckBox);
         tn3270eCheckBox.setFont(ThemeManager.getUiFont());
         tn3270eCheckBox.setSelected(haus.nightmare.j3270.config.Settings.getAutoConnectTn3270e());
-        mainPanel.add(tn3270eCheckBox, gbc);
+        contentPanel.add(tn3270eCheckBox, gbc);
 
-        // Keep-Alive Checkbox
+        gridy++;
+
+        // 11. Keep-Alive Checkbox
         gbc.gridx = 1;
-        gbc.gridy = 10;
+        gbc.gridy = gridy;
         keepAliveCheckBox = new JCheckBox("Enable Keep-Alive Heartbeat (NOP)");
         ThemeManager.styleCheckBox(keepAliveCheckBox);
         keepAliveCheckBox.setFont(ThemeManager.getUiFont());
         keepAliveCheckBox.setSelected(haus.nightmare.j3270.config.Settings.getAutoConnectKeepAlive());
-        mainPanel.add(keepAliveCheckBox, gbc);
+        contentPanel.add(keepAliveCheckBox, gbc);
 
-        // Auto-Reconnect Checkbox
+        gridy++;
+
+        // 12. Auto-Reconnect Checkbox
         gbc.gridx = 1;
-        gbc.gridy = 11;
+        gbc.gridy = gridy;
         autoReconnectCheckBox = new JCheckBox("Auto-Reconnect on Disconnect");
         ThemeManager.styleCheckBox(autoReconnectCheckBox);
         autoReconnectCheckBox.setFont(ThemeManager.getUiFont());
         autoReconnectCheckBox.setSelected(haus.nightmare.j3270.config.Settings.getAutoConnectAutoReconnect());
-        mainPanel.add(autoReconnectCheckBox, gbc);
+        contentPanel.add(autoReconnectCheckBox, gbc);
+
+        gridy++;
+
+        // 13. PER-CONNECTION PROXY CONFIGURATION PANEL
+        gbc.gridx = 0;
+        gbc.gridy = gridy;
+        gbc.gridwidth = 2;
+        gbc.weightx = 1.0;
+
+        JPanel proxyGroup = new JPanel(new GridBagLayout());
+        proxyGroup.setBorder(BorderFactory.createTitledBorder(
+                BorderFactory.createEtchedBorder(),
+                "Proxy Configuration (This Connection)",
+                TitledBorder.LEFT,
+                TitledBorder.TOP,
+                labelFont
+        ));
+        GridBagConstraints pgbc = new GridBagConstraints();
+        pgbc.insets = new Insets(3, 6, 3, 6);
+        pgbc.fill = GridBagConstraints.HORIZONTAL;
+
+        // Proxy Type
+        pgbc.gridx = 0;
+        pgbc.gridy = 0;
+        pgbc.weightx = 0;
+        JLabel ptLabel = new JLabel("Proxy Type:");
+        ptLabel.setFont(labelFont);
+        proxyGroup.add(ptLabel, pgbc);
+
+        pgbc.gridx = 1;
+        pgbc.gridwidth = 3;
+        pgbc.weightx = 1.0;
+        proxyTypeCombo = new JComboBox<>(ConnectionConfig.ProxyType.values());
+        proxyTypeCombo.setSelectedItem(ConnectionConfig.ProxyType.NONE);
+        proxyTypeCombo.setFont(ThemeManager.getUiFont());
+        ThemeManager.styleComboBox(proxyTypeCombo);
+        proxyGroup.add(proxyTypeCombo, pgbc);
+
+        // Proxy Host & Port
+        pgbc.gridx = 0;
+        pgbc.gridy = 1;
+        pgbc.gridwidth = 1;
+        pgbc.weightx = 0;
+        JLabel phLabel = new JLabel("Proxy Host:");
+        phLabel.setFont(labelFont);
+        proxyGroup.add(phLabel, pgbc);
+
+        pgbc.gridx = 1;
+        pgbc.weightx = 1.0;
+        proxyHostField = createField(14);
+        proxyGroup.add(proxyHostField, pgbc);
+
+        pgbc.gridx = 2;
+        pgbc.weightx = 0;
+        JLabel ppLabel = new JLabel("Port:");
+        ppLabel.setFont(labelFont);
+        proxyGroup.add(ppLabel, pgbc);
+
+        pgbc.gridx = 3;
+        pgbc.weightx = 0.4;
+        proxyPortField = createField(5);
+        proxyGroup.add(proxyPortField, pgbc);
+
+        // Proxy User & Password
+        pgbc.gridx = 0;
+        pgbc.gridy = 2;
+        pgbc.gridwidth = 1;
+        pgbc.weightx = 0;
+        JLabel puLabel = new JLabel("Username:");
+        puLabel.setFont(labelFont);
+        proxyGroup.add(puLabel, pgbc);
+
+        pgbc.gridx = 1;
+        pgbc.weightx = 1.0;
+        proxyUserField = createField(12);
+        proxyGroup.add(proxyUserField, pgbc);
+
+        pgbc.gridx = 2;
+        pgbc.weightx = 0;
+        JLabel pwLabel = new JLabel("Password:");
+        pwLabel.setFont(labelFont);
+        proxyGroup.add(pwLabel, pgbc);
+
+        pgbc.gridx = 3;
+        pgbc.weightx = 0.4;
+        proxyPassField = createPasswordField(10);
+        proxyGroup.add(proxyPassField, pgbc);
+
+        // Dynamic enable/disable based on Proxy Type
+        Runnable updateProxyFields = () -> {
+            ConnectionConfig.ProxyType pt = (ConnectionConfig.ProxyType) proxyTypeCombo.getSelectedItem();
+            boolean active = (pt != null && pt != ConnectionConfig.ProxyType.NONE);
+            proxyHostField.setEnabled(active);
+            proxyPortField.setEnabled(active);
+            proxyUserField.setEnabled(active);
+            proxyPassField.setEnabled(active && pt != ConnectionConfig.ProxyType.SOCKS4);
+
+            if (active) {
+                String currentPPort = proxyPortField.getText().trim();
+                if (currentPPort.isEmpty() || "0".equals(currentPPort)) {
+                    proxyPortField.setText(pt == ConnectionConfig.ProxyType.HTTP ? "8080" : "1080");
+                }
+            }
+        };
+        proxyTypeCombo.addActionListener(e -> updateProxyFields.run());
+        updateProxyFields.run();
+
+        contentPanel.add(proxyGroup, gbc);
+
+        gridy++;
+
+        // 14. Action Buttons
+        gbc.gridx = 0;
+        gbc.gridy = gridy;
+        gbc.gridwidth = 2;
+        gbc.weightx = 1.0;
 
-        // Buttons
         JPanel buttonPanel = new JPanel(new FlowLayout(FlowLayout.RIGHT, 8, 4));
 
         JButton connectBtn = new JButton("Connect");
@@ -285,13 +487,14 @@ public class ConnectDialog extends JDialog {
 
         buttonPanel.add(cancelBtn);
         buttonPanel.add(connectBtn);
+        contentPanel.add(buttonPanel, gbc);
 
-        gbc.gridx = 0;
+        JScrollPane scrollPane = new JScrollPane(contentPanel);
-        gbc.gridy = 12;
+        scrollPane.setBorder(BorderFactory.createEmptyBorder());
-        gbc.gridwidth = 2;
+        scrollPane.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
-        mainPanel.add(buttonPanel, gbc);
+        scrollPane.getVerticalScrollBar().setUnitIncrement(14);
+        setContentPane(scrollPane);
 
-        setContentPane(mainPanel);
         ThemeManager.applyThemeToWindow(this);
 
         // Enter key triggers connect
@@ -305,6 +508,189 @@ public class ConnectDialog extends JDialog {
         return field;
     }
 
+    private JPasswordField createPasswordField(int cols) {
+        JPasswordField field = new JPasswordField(cols);
+        field.setFont(ThemeManager.getMonospacedUiFont());
+        ThemeManager.styleTextField(field);
+        return field;
+    }
+
+    // ================= Profile Management =================
+
+    private void refreshProfileCombo() {
+        profileCombo.removeAllItems();
+        profileCombo.addItem(NEW_PROFILE_LABEL);
+        List<SavedHost> saved = HostStorage.getSavedHosts();
+        for (SavedHost h : saved) {
+            profileCombo.addItem(h);
+        }
+        if (selectedProfileId != null) {
+            for (int i = 0; i < profileCombo.getItemCount(); i++) {
+                Object item = profileCombo.getItemAt(i);
+                if (item instanceof SavedHost && ((SavedHost) item).getId().equals(selectedProfileId)) {
+                    profileCombo.setSelectedIndex(i);
+                    return;
+                }
+            }
+        }
+        profileCombo.setSelectedIndex(0);
+    }
+
+    private void onProfileSelectionChanged() {
+        Object sel = profileCombo.getSelectedItem();
+        if (sel instanceof SavedHost) {
+            SavedHost h = (SavedHost) sel;
+            selectedProfileId = h.getId();
+            deleteProfileBtn.setEnabled(true);
+            loadProfileFields(h);
+        } else {
+            selectedProfileId = null;
+            deleteProfileBtn.setEnabled(false);
+        }
+    }
+
+    public void loadProfile(SavedHost h) {
+        if (h == null) return;
+        selectedProfileId = h.getId();
+        refreshProfileCombo();
+        loadProfileFields(h);
+    }
+
+    private void loadProfileFields(SavedHost h) {
+        if (h == null) return;
+        hostField.setText(h.getHost());
+        portField.setText(String.valueOf(h.getPort()));
+        if (h.getModel() == 0) {
+            modelCombo.setSelectedItem(TerminalModel.IBM_DYNAMIC);
+        } else {
+            try {
+                modelCombo.setSelectedItem(TerminalModel.forModel(h.getModel(), true));
+            } catch (Exception ignored) {
+            }
+        }
+        dynamicRowsSpinner.setValue(h.getDynamicRows() > 0 ? h.getDynamicRows() : 62);
+        dynamicColsSpinner.setValue(h.getDynamicCols() > 0 ? h.getDynamicCols() : 160);
+        luField.setText(h.getLuName() != null ? h.getLuName() : "");
+        tlsCheckBox.setSelected(h.isUseTls());
+        verifyCertCheckBox.setEnabled(h.isUseTls());
+        verifyCertCheckBox.setSelected(h.isTlsVerifyCert());
+        tn3270eCheckBox.setSelected(h.isTn3270e());
+        setInitialCodePage(h.getCodePage());
+
+        if (h.getGraphicsMode() != null) {
+            graphicsCombo.setSelectedItem(haus.nightmare.lib3270j.graphics.GraphicsMode.fromString(h.getGraphicsMode()));
+        }
+
+        // Per-connection proxy parameters
+        String ptStr = h.getProxyType();
+        try {
+            ConnectionConfig.ProxyType pt = (ptStr != null && !ptStr.trim().isEmpty())
+                    ? ConnectionConfig.ProxyType.valueOf(ptStr.toUpperCase())
+                    : ConnectionConfig.ProxyType.NONE;
+            proxyTypeCombo.setSelectedItem(pt);
+        } catch (IllegalArgumentException e) {
+            proxyTypeCombo.setSelectedItem(ConnectionConfig.ProxyType.NONE);
+        }
+        proxyHostField.setText(h.getProxyHost() != null ? h.getProxyHost() : "");
+        proxyPortField.setText(h.getProxyPort() > 0 ? String.valueOf(h.getProxyPort()) : "");
+        proxyUserField.setText(h.getProxyUsername() != null ? h.getProxyUsername() : "");
+        proxyPassField.setText(h.getProxyPassword() != null ? h.getProxyPassword() : "");
+    }
+
+    private void onSaveProfile() {
+        String hStr = hostField.getText().trim();
+        if (hStr.isEmpty()) {
+            hostField.requestFocus();
+            JOptionPane.showMessageDialog(this, "Please specify a host before saving profile.", "Missing Host", JOptionPane.WARNING_MESSAGE);
+            return;
+        }
+
+        String defaultName = hStr;
+        Object currentSel = profileCombo.getSelectedItem();
+        if (currentSel instanceof SavedHost) {
+            defaultName = ((SavedHost) currentSel).getName();
+        }
+
+        String profileName = (String) JOptionPane.showInputDialog(
+                this,
+                "Enter Host Profile Name:",
+                "Save Profile",
+                JOptionPane.PLAIN_MESSAGE,
+                null,
+                null,
+                defaultName
+        );
+
+        if (profileName == null || profileName.trim().isEmpty()) {
+            return;
+        }
+        profileName = profileName.trim();
+
+        SavedHost hostToSave = buildCurrentSavedHost(profileName);
+        HostStorage.saveHost(hostToSave);
+        selectedProfileId = hostToSave.getId();
+        refreshProfileCombo();
+    }
+
+    private void onDeleteProfile() {
+        if (selectedProfileId == null) return;
+        int opt = JOptionPane.showConfirmDialog(this,
+                "Are you sure you want to delete this host profile?",
+                "Delete Profile",
+                JOptionPane.YES_NO_OPTION);
+        if (opt == JOptionPane.YES_OPTION) {
+            HostStorage.deleteHost(selectedProfileId);
+            selectedProfileId = null;
+            refreshProfileCombo();
+        }
+    }
+
+    private SavedHost buildCurrentSavedHost(String profileName) {
+        String id = selectedProfileId != null ? selectedProfileId : java.util.UUID.randomUUID().toString();
+        String h = hostField.getText().trim();
+        int port = 23;
+        try {
+            port = Integer.parseInt(portField.getText().trim());
+        } catch (NumberFormatException ignored) {}
+
+        TerminalModel m = (TerminalModel) modelCombo.getSelectedItem();
+        int mNum = (m != null) ? m.getModelNumber() : 4;
+        int dRows = (Integer) dynamicRowsSpinner.getValue();
+        int dCols = (Integer) dynamicColsSpinner.getValue();
+        String lu = luField.getText().trim();
+        boolean tls = tlsCheckBox.isSelected();
+        boolean verify = verifyCertCheckBox.isSelected();
+        boolean tn3270e = tn3270eCheckBox.isSelected();
+
+        String gfx = "BOTH";
+        if (graphicsCombo.getSelectedItem() != null) {
+            gfx = graphicsCombo.getSelectedItem().toString();
+        }
+
+        String cp = "037";
+        Object cpSel = codePageCombo.getSelectedItem();
+        if (cpSel != null) {
+            String s = cpSel.toString().trim();
+            int dash = s.indexOf(" -");
+            cp = (dash > 0) ? s.substring(0, dash).trim() : s;
+        }
+
+        ConnectionConfig.ProxyType pt = (ConnectionConfig.ProxyType) proxyTypeCombo.getSelectedItem();
+        String ptStr = (pt != null) ? pt.name() : "NONE";
+        String pHost = proxyHostField.getText().trim();
+        int pPort = 0;
+        try {
+            pPort = Integer.parseInt(proxyPortField.getText().trim());
+        } catch (NumberFormatException ignored) {}
+        String pUser = proxyUserField.getText().trim();
+        String pPass = new String(proxyPassField.getPassword());
+
+        return new SavedHost(id, profileName, h, port, mNum, dRows, dCols, lu, false,
+                "TSO", tls, verify, tn3270e, gfx, cp, ptStr, pHost, pPort, pUser, pPass);
+    }
+
+    // ================= Connect Action =================
+
     private void onConnect() {
         String host = hostField.getText().trim();
         if (host.isEmpty()) {
@@ -321,19 +707,32 @@ public class ConnectDialog extends JDialog {
         }
 
         TerminalModel selectedModel = (TerminalModel) modelCombo.getSelectedItem();
+        if (selectedModel == null) {
+            selectedModel = TerminalModel.IBM_3279_4;
+        }
+
+        // Support full host string parsing if the user pasted flags or prefixes into host field
+        if (host.contains(" ") || host.startsWith("L:") || host.startsWith("P:") || host.startsWith("--proxy=") || host.startsWith("-proxy=")) {
+            result = ConnectionConfig.parseHostString(host, port, selectedModel);
+        } else {
             result = new ConnectionConfig(host, port, selectedModel);
-        if (selectedModel != null && selectedModel.isDynamic()) {
+        }
+
+        if (selectedModel.isDynamic()) {
             int dRows = (Integer) dynamicRowsSpinner.getValue();
             int dCols = (Integer) dynamicColsSpinner.getValue();
             result.setDynamicDimensions(dRows, dCols);
             haus.nightmare.j3270.config.Settings.setDynamicRows(dRows);
             haus.nightmare.j3270.config.Settings.setDynamicCols(dCols);
         }
+
         String lu = luField.getText().trim();
         if (!lu.isEmpty()) {
             result.setLuName(lu);
         }
+        if (graphicsCombo.getSelectedItem() != null) {
             result.setGraphicsMode((haus.nightmare.lib3270j.graphics.GraphicsMode) graphicsCombo.getSelectedItem());
+        }
 
         Object cpSelection = codePageCombo.getSelectedItem();
         if (cpSelection != null) {
@@ -361,6 +760,22 @@ public class ConnectDialog extends JDialog {
         result.setReconnectMaxRetries(haus.nightmare.j3270.config.Settings.getAutoConnectReconnectMaxRetries());
         haus.nightmare.j3270.config.Settings.setAutoConnectAutoReconnect(ar);
 
+        // Apply per-connection proxy parameters strictly to this connection
+        ConnectionConfig.ProxyType pType = (ConnectionConfig.ProxyType) proxyTypeCombo.getSelectedItem();
+        String pHost = proxyHostField.getText().trim();
+        if (pType != null && pType != ConnectionConfig.ProxyType.NONE && !pHost.isEmpty()) {
+            int pPort = 0;
+            try {
+                pPort = Integer.parseInt(proxyPortField.getText().trim());
+            } catch (NumberFormatException ignored) {}
+            if (pPort <= 0) {
+                pPort = (pType == ConnectionConfig.ProxyType.HTTP) ? 8080 : 1080;
+            }
+            String pUser = proxyUserField.getText().trim();
+            String pPass = new String(proxyPassField.getPassword());
+            result.setProxy(pType, pHost, pPort, pUser.isEmpty() ? null : pUser, pPass.isEmpty() ? null : pPass);
+        }
+
         confirmed = true;
         dispose();
     }
@@ -407,4 +822,49 @@ public class ConnectDialog extends JDialog {
             codePageCombo.setSelectedItem(cp);
         }
     }
+
+    /**
+     * Set initial proxy settings for this connection.
+     */
+    public void setInitialProxy(ConnectionConfig.ProxyType type, String host, int port, String user, String pass) {
+        if (proxyTypeCombo != null) {
+            proxyTypeCombo.setSelectedItem(type != null ? type : ConnectionConfig.ProxyType.NONE);
+        }
+        if (proxyHostField != null) {
+            proxyHostField.setText(host != null ? host : "");
+        }
+        if (proxyPortField != null) {
+            proxyPortField.setText(port > 0 ? String.valueOf(port) : "");
+        }
+        if (proxyUserField != null) {
+            proxyUserField.setText(user != null ? user : "");
+        }
+        if (proxyPassField != null) {
+            proxyPassField.setText(pass != null ? pass : "");
+        }
+    }
+
+    public ConnectionConfig.ProxyType getSelectedProxyType() {
+        return (ConnectionConfig.ProxyType) proxyTypeCombo.getSelectedItem();
+    }
+
+    public String getProxyHost() {
+        return proxyHostField.getText().trim();
+    }
+
+    public int getProxyPort() {
+        try {
+            return Integer.parseInt(proxyPortField.getText().trim());
+        } catch (Exception e) {
+            return 0;
+        }
+    }
+
+    public String getProxyUsername() {
+        return proxyUserField.getText().trim();
+    }
+
+    public String getProxyPassword() {
+        return new String(proxyPassField.getPassword());
+    }
 }

j3270/src/test/java/haus/nightmare/j3270/storage/HostStorageAndProxyTest.java

@@ -0,0 +1,307 @@
+package haus.nightmare.j3270.storage;
+
+import haus.nightmare.j3270.ui.ConnectDialog;
+import haus.nightmare.lib3270j.ConnectionConfig;
+import haus.nightmare.lib3270j.TerminalModel;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.awt.Frame;
+import java.awt.GraphicsEnvironment;
+import java.util.List;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class HostStorageAndProxyTest {
+
+    private List<SavedHost> originalHosts;
+
+    @BeforeEach
+    public void setUp() {
+        originalHosts = HostStorage.getSavedHosts();
+        HostStorage.clearAll();
+    }
+
+    @AfterEach
+    public void tearDown() {
+        HostStorage.clearAll();
+        HostStorage.saveAll(originalHosts);
+    }
+
+    @Test
+    @DisplayName("SavedHost correctly models per-connection proxy and converts to ConnectionConfig")
+    public void testSavedHostProxyToConnectionConfig() {
+        // 1. Host with SOCKS5 proxy and auth
+        SavedHost host1 = new SavedHost(
+                UUID.randomUUID().toString(),
+                "Prod Mainframe",
+                "mvs.corp.local",
+                2323,
+                4,
+                43,
+                80,
+                "TSO01",
+                false,
+                "TSO",
+                true,
+                true,
+                true,
+                "BOTH",
+                "037",
+                "SOCKS5",
+                "proxy.internal.corp",
+                1080,
+                "admin",
+                "secret123"
+        );
+
+        ConnectionConfig cfg1 = host1.toConnectionConfig();
+        assertEquals("mvs.corp.local", cfg1.getHost());
+        assertEquals(2323, cfg1.getPort());
+        assertTrue(cfg1.isUseTls());
+        assertEquals("TSO01", cfg1.getLuName());
+        assertEquals(ConnectionConfig.ProxyType.SOCKS5, cfg1.getProxyType());
+        assertEquals("proxy.internal.corp", cfg1.getProxyHost());
+        assertEquals(1080, cfg1.getProxyPort());
+        assertEquals("admin", cfg1.getProxyUsername());
+        assertEquals("secret123", cfg1.getProxyPassword());
+
+        // 2. Host with direct connection (NONE proxy)
+        SavedHost host2 = new SavedHost(
+                UUID.randomUUID().toString(),
+                "Local VM370",
+                "127.0.0.1",
+                23,
+                2,
+                24,
+                80,
+                "",
+                false,
+                "CMS",
+                false,
+                false,
+                false,
+                "BOTH",
+                "037",
+                "NONE",
+                "",
+                0,
+                "",
+                ""
+        );
+
+        ConnectionConfig cfg2 = host2.toConnectionConfig();
+        assertEquals("127.0.0.1", cfg2.getHost());
+        assertEquals(23, cfg2.getPort());
+        assertFalse(cfg2.isUseTls());
+        assertEquals(ConnectionConfig.ProxyType.NONE, cfg2.getProxyType());
+        assertNull(cfg2.getProxyHost());
+    }
+
+    @Test
+    @DisplayName("HostStorage persists and restores multiple host profiles with isolated per-connection proxies")
+    public void testHostStoragePersistenceAndIsolation() {
+        SavedHost h1 = new SavedHost(
+                "id-1",
+                "System A (SOCKS5)",
+                "sysa.corp",
+                23,
+                4,
+                62,
+                160,
+                "",
+                false,
+                "TSO",
+                false,
+                true,
+                true,
+                "BOTH",
+                "037",
+                "SOCKS5",
+                "socks.gateway.net",
+                1080,
+                "alice",
+                "passA"
+        );
+
+        SavedHost h2 = new SavedHost(
+                "id-2",
+                "System B (HTTP CONNECT)",
+                "sysb.dmz",
+                992,
+                5,
+                27,
+                132,
+                "LU99",
+                false,
+                "TSO",
+                true,
+                true,
+                true,
+                "BOTH",
+                "1047",
+                "HTTP",
+                "squid.proxy.org",
+                3128,
+                "bob",
+                "passB"
+        );
+
+        SavedHost h3 = new SavedHost(
+                "id-3",
+                "System C (Direct)",
+                "sysc.lan",
+                23,
+                2,
+                24,
+                80,
+                "",
+                true, // autoConnect
+                "CMS",
+                false,
+                true,
+                true,
+                "BOTH",
+                "500",
+                "NONE",
+                "",
+                0,
+                "",
+                ""
+        );
+
+        HostStorage.saveHost(h1);
+        HostStorage.saveHost(h2);
+        HostStorage.saveHost(h3);
+
+        List<SavedHost> loaded = HostStorage.getSavedHosts();
+        assertEquals(3, loaded.size());
+
+        SavedHost loadedA = HostStorage.findById("id-1");
+        assertNotNull(loadedA);
+        assertEquals("System A (SOCKS5)", loadedA.getName());
+        assertEquals("SOCKS5", loadedA.getProxyType());
+        assertEquals("socks.gateway.net", loadedA.getProxyHost());
+        assertEquals(1080, loadedA.getProxyPort());
+        assertEquals("alice", loadedA.getProxyUsername());
+        assertEquals("passA", loadedA.getProxyPassword());
+
+        SavedHost loadedB = HostStorage.findById("id-2");
+        assertNotNull(loadedB);
+        assertEquals("HTTP", loadedB.getProxyType());
+        assertEquals("squid.proxy.org", loadedB.getProxyHost());
+        assertEquals(3128, loadedB.getProxyPort());
+        assertEquals("bob", loadedB.getProxyUsername());
+        assertEquals("passB", loadedB.getProxyPassword());
+
+        SavedHost loadedC = HostStorage.findById("id-3");
+        assertNotNull(loadedC);
+        assertEquals("NONE", loadedC.getProxyType());
+        assertEquals("", loadedC.getProxyHost());
+        assertTrue(loadedC.isAutoConnect());
+
+        // Verify getAutoConnectHost returns System C with its own connection settings
+        SavedHost auto = HostStorage.getAutoConnectHost();
+        assertNotNull(auto);
+        assertEquals("id-3", auto.getId());
+        assertEquals(ConnectionConfig.ProxyType.NONE, auto.toConnectionConfig().getProxyType());
+
+        // Verify deleteHost
+        HostStorage.deleteHost("id-2");
+        assertEquals(2, HostStorage.getSavedHosts().size());
+        assertNull(HostStorage.findById("id-2"));
+    }
+
+    @Test
+    @DisplayName("HostStorage JSON matches a3270 format and parses a3270 JSON strings")
+    public void testA3270JsonFormatCompatibility() {
+        // String representative of a3270 saved_hosts preference JSON
+        String a3270Json = "[\n" +
+                "  {\n" +
+                "    \"id\": \"android-uuid-1\",\n" +
+                "    \"name\": \"Dallas Mainframe\",\n" +
+                "    \"host\": \"dallas.ibm.com\",\n" +
+                "    \"port\": 2323,\n" +
+                "    \"model\": 4,\n" +
+                "    \"dynamicRows\": 62,\n" +
+                "    \"dynamicCols\": 160,\n" +
+                "    \"luName\": \"DAL01\",\n" +
+                "    \"autoConnect\": false,\n" +
+                "    \"hostType\": \"TSO\",\n" +
+                "    \"useTls\": true,\n" +
+                "    \"tlsVerifyCert\": false,\n" +
+                "    \"tn3270e\": true,\n" +
+                "    \"graphicsMode\": \"BOTH\",\n" +
+                "    \"codePage\": \"037\",\n" +
+                "    \"proxyType\": \"SOCKS5\",\n" +
+                "    \"proxyHost\": \"10.20.30.40\",\n" +
+                "    \"proxyPort\": 9050,\n" +
+                "    \"proxyUsername\": \"dallasuser\",\n" +
+                "    \"proxyPassword\": \"dallaspass\"\n" +
+                "  }\n" +
+                "]";
+
+        List<SavedHost> parsed = HostStorage.parseHostsJson(a3270Json);
+        assertEquals(1, parsed.size());
+        SavedHost h = parsed.get(0);
+        assertEquals("android-uuid-1", h.getId());
+        assertEquals("Dallas Mainframe", h.getName());
+        assertEquals("dallas.ibm.com", h.getHost());
+        assertEquals(2323, h.getPort());
+        assertEquals(4, h.getModel());
+        assertTrue(h.isUseTls());
+        assertFalse(h.isTlsVerifyCert());
+        assertEquals("SOCKS5", h.getProxyType());
+        assertEquals("10.20.30.40", h.getProxyHost());
+        assertEquals(9050, h.getProxyPort());
+        assertEquals("dallasuser", h.getProxyUsername());
+        assertEquals("dallaspass", h.getProxyPassword());
+
+        // Roundtrip serialization
+        String serialized = HostStorage.serializeHostsJson(parsed);
+        List<SavedHost> roundtripped = HostStorage.parseHostsJson(serialized);
+        assertEquals(1, roundtripped.size());
+        SavedHost r = roundtripped.get(0);
+        assertEquals(h.getId(), r.getId());
+        assertEquals(h.getProxyType(), r.getProxyType());
+        assertEquals(h.getProxyHost(), r.getProxyHost());
+        assertEquals(h.getProxyPort(), r.getProxyPort());
+        assertEquals(h.getProxyUsername(), r.getProxyUsername());
+        assertEquals(h.getProxyPassword(), r.getProxyPassword());
+    }
+
+    @Test
+    @DisplayName("ConnectDialog loads profile proxy and applies per-connection proxy to ConnectionConfig")
+    public void testConnectDialogProxyHandling() {
+        if (!GraphicsEnvironment.isHeadless()) {
+            ConnectDialog dialog = new ConnectDialog((Frame) null);
+            dialog.setInitialHost("test.mainframe.com");
+            dialog.setInitialPort(23);
+            dialog.setInitialProxy(ConnectionConfig.ProxyType.SOCKS5, "127.0.0.1", 1080, "testuser", "testpass");
+
+            assertEquals(ConnectionConfig.ProxyType.SOCKS5, dialog.getSelectedProxyType());
+            assertEquals("127.0.0.1", dialog.getProxyHost());
+            assertEquals(1080, dialog.getProxyPort());
+            assertEquals("testuser", dialog.getProxyUsername());
+            assertEquals("testpass", dialog.getProxyPassword());
+
+            // Loading a profile updates dialog proxy fields
+            SavedHost profile = new SavedHost(
+                    "p1", "Profile 1", "prod.ibm.net", 992, 4, 43, 80, "", false,
+                    "TSO", true, true, true, "BOTH", "037",
+                    "HTTP", "proxy.corp.net", 8080, "corpuser", "corppass"
+            );
+            dialog.loadProfile(profile);
+
+            assertEquals(ConnectionConfig.ProxyType.HTTP, dialog.getSelectedProxyType());
+            assertEquals("proxy.corp.net", dialog.getProxyHost());
+            assertEquals(8080, dialog.getProxyPort());
+            assertEquals("corpuser", dialog.getProxyUsername());
+            assertEquals("corppass", dialog.getProxyPassword());
+            dialog.dispose();
+        }
+    }
+}

lib3270j/src/main/java/haus/nightmare/lib3270j/datastream/DataStreamProcessor.java

@@ -548,6 +548,8 @@ public class DataStreamProcessor {
                             applyExtendedAttribute(ea, attrType, attrValue);
                         }
                     }
+                    baddr = (baddr + 1) % size;
+                    screen.setBufferAddress(baddr);
                     pos += 2 + nPairs * 2;
                     lastWasOrder = true;
                     break;

lib3270j/src/test/java/haus/nightmare/lib3270j/datastream/DataStreamProcessorTest.java

@@ -198,4 +198,77 @@ public class DataStreamProcessorTest {
         processor.processRecord(ewStream.toByteArray(), 0, ewStream.size(), true);
         assertEquals((byte) 0, screen.getCell(0).fg);
     }
+
+    @Test
+    public void testModifyFieldAdvancesBufferAddressAndPreservesFieldAttributes() throws java.io.IOException {
+        // Step 1: Initialize screen with an Erase/Write defining two fields
+        java.io.ByteArrayOutputStream initStream = new java.io.ByteArrayOutputStream();
+        initStream.write(CMD_EW);
+        initStream.write(0xC3);
+        // Field 1 at pos 0: SFE with FA_PRINTABLE, text "ABC"
+        initStream.write(ORDER_SBA);
+        initStream.write(0x40); initStream.write(0x40); // pos 0
+        initStream.write(ORDER_SFE);
+        initStream.write(0x01); // 1 pair
+        initStream.write(XA_3270);
+        initStream.write(FA_PRINTABLE);
+        initStream.write(translator.stringToEbcdic("ABC"));
+
+        // Field 2 at pos 10: SFE with FA_PRINTABLE, text "XYZ"
+        initStream.write(ORDER_SBA);
+        byte[] addr10 = encodeAddress(10, screen.getRows(), screen.getCols());
+        initStream.write(addr10);
+        initStream.write(ORDER_SFE);
+        initStream.write(0x01);
+        initStream.write(XA_3270);
+        initStream.write(FA_PRINTABLE);
+        initStream.write(translator.stringToEbcdic("XYZ"));
+
+        processor.processRecord(initStream.toByteArray(), 0, initStream.size(), true);
+
+        assertTrue(screen.getCell(0).isFieldAttribute());
+        assertEquals('A', screen.getCell(1).ucs4);
+        assertTrue(screen.getCell(10).isFieldAttribute());
+        assertEquals('X', screen.getCell(11).ucs4);
+
+        // Step 2: Issue a Write command that uses ORDER_MF on Field 1 and Field 2
+        java.io.ByteArrayOutputStream updateStream = new java.io.ByteArrayOutputStream();
+        updateStream.write(CMD_W);
+        updateStream.write(0xC1);
+        // SBA to pos 0
+        updateStream.write(ORDER_SBA);
+        updateStream.write(0x40); updateStream.write(0x40);
+        // MF on pos 0: set foreground to green (0xF4)
+        updateStream.write(ORDER_MF);
+        updateStream.write(0x01); // 1 pair
+        updateStream.write(XA_FOREGROUND);
+        updateStream.write(0xF4);
+        // Data "123" following MF directly
+        updateStream.write(translator.stringToEbcdic("123"));
+
+        // MF on pos 10
+        updateStream.write(ORDER_SBA);
+        updateStream.write(addr10);
+        updateStream.write(ORDER_MF);
+        updateStream.write(0x01);
+        updateStream.write(XA_FOREGROUND);
+        updateStream.write(0xF5); // turquoise
+        updateStream.write(translator.stringToEbcdic("789"));
+
+        processor.processRecord(updateStream.toByteArray(), 0, updateStream.size(), false);
+
+        // Verify Field 1: pos 0 MUST still be a field attribute, NOT overwritten by '1'
+        assertTrue(screen.getCell(0).isFieldAttribute(), "Position 0 must remain a field attribute");
+        assertEquals((byte) 0xF4, screen.getCell(0).fg, "Position 0 field attribute must have updated fg");
+        assertEquals('1', screen.getCell(1).ucs4, "Data must start at pos 1, not overwrite pos 0");
+        assertEquals('2', screen.getCell(2).ucs4);
+        assertEquals('3', screen.getCell(3).ucs4);
+
+        // Verify Field 2: pos 10 MUST still be a field attribute, NOT overwritten by '7'
+        assertTrue(screen.getCell(10).isFieldAttribute(), "Position 10 must remain a field attribute");
+        assertEquals((byte) 0xF5, screen.getCell(10).fg, "Position 10 field attribute must have updated fg");
+        assertEquals('7', screen.getCell(11).ucs4, "Data must start at pos 11, not overwrite pos 10");
+        assertEquals('8', screen.getCell(12).ucs4);
+        assertEquals('9', screen.getCell(13).ucs4);
+    }
 }