MCP initial files

src/main/java/com/elphel/imagej/mcp/McpDialogField.java

+package com.elphel.imagej.mcp;
+
+public class McpDialogField {
+    public enum Type {
+        MESSAGE,
+        BOOLEAN,
+        NUMBER,
+        STRING,
+        CHOICE
+    }
+
+    public final Type type;
+    public final String label;
+    public final String tooltip;
+    public final String tab;
+    public final String units;
+    public final String[] choices;
+    public final String defaultValue;
+
+    public McpDialogField(Type type,
+                          String label,
+                          String tooltip,
+                          String tab,
+                          String units,
+                          String[] choices,
+                          String defaultValue) {
+        this.type = type;
+        this.label = label;
+        this.tooltip = tooltip;
+        this.tab = tab;
+        this.units = units;
+        this.choices = choices;
+        this.defaultValue = defaultValue;
+    }
+}

src/main/java/com/elphel/imagej/mcp/McpDialogRegistry.java

+package com.elphel.imagej.mcp;
+
+import java.util.concurrent.atomic.AtomicReference;
+
+public class McpDialogRegistry {
+    private static final AtomicReference<McpDialogSession> CURRENT = new AtomicReference<McpDialogSession>(null);
+
+    private McpDialogRegistry() {
+    }
+
+    public static void setCurrent(McpDialogSession session) {
+        CURRENT.set(session);
+    }
+
+    public static McpDialogSession getCurrent() {
+        return CURRENT.get();
+    }
+
+    public static void setValue(String label, String value) {
+        McpDialogSession session = CURRENT.get();
+        if (session == null) {
+            return;
+        }
+        session.setValue(label, value);
+    }
+}

src/main/java/com/elphel/imagej/mcp/McpDialogSession.java

+package com.elphel.imagej.mcp;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+public class McpDialogSession {
+    private final String id;
+    private final String title;
+    private final List<McpDialogField> fields;
+    private final Map<String, String> valuesByLabel;
+
+    public McpDialogSession(String title, List<McpDialogField> fields) {
+        this.id = UUID.randomUUID().toString();
+        this.title = title;
+        this.fields = new ArrayList<McpDialogField>(fields);
+        this.valuesByLabel = new HashMap<String, String>();
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public List<McpDialogField> getFields() {
+        return Collections.unmodifiableList(fields);
+    }
+
+    public void setValue(String label, String value) {
+        if (label == null) {
+            return;
+        }
+        valuesByLabel.put(label, value);
+    }
+
+    public String getValue(String label) {
+        if (label == null) {
+            return null;
+        }
+        return valuesByLabel.get(label);
+    }
+}