1 files changed, 38 insertions, 5 deletions

diff --git a/src/ast/nodes/AtomNode.java b/src/ast/nodes/AtomNode.java
index 4dcb926..ceafc07 100644
--- a/src/ast/nodes/AtomNode.java
+++ b/src/ast/nodes/AtomNode.java
@@ -1,30 +1,63 @@
 package ast.nodes;
 
+import ast.types.*;
 import java.util.ArrayList;
-
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import semanticanalysis.SemanticError;
 import semanticanalysis.SymbolTable;
-import ast.types.*;
 
 /**
  * Node for the `atom` statement of the grammar.
  */
 public class AtomNode implements Node {
+
     protected String val;
 
     public AtomNode(String val) {
         this.val = val;
     }
 
+    public String getId() {
+        return this.val;
+    }
+
     @Override
     public ArrayList<SemanticError> checkSemantics(SymbolTable ST, int _nesting) {
-        return new ArrayList<SemanticError>();
+        var errors = new ArrayList<SemanticError>();
+
+        if ((this.typeCheck() instanceof AtomType) && ST.nslookup(this.getId()) < 0) {
+            errors.add(new SemanticError("'" + this.getId() + "' is not defined."));
+        }
+
+        return errors;
     }
 
-    // FIXME: this type for atom
+    // ENHANCE: return more specific types
     @Override
     public Type typeCheck() {
-        return new AtomType();
+        Pattern booleanVariable = Pattern.compile("^(True|False)$");
+        Pattern continueBreakVariable = Pattern.compile("^(continue|break)$");
+        // this regex should match every possible atom name written in this format: CHAR (CHAR | DIGIT)*
+        Pattern simpleVariable = Pattern.compile("^[a-zA-Z][a-zA-Z0-9]*$", Pattern.CASE_INSENSITIVE);
+        
+        Matcher booleanVariableMatcher = booleanVariable.matcher(this.val);
+        Matcher continueBreakVariableMatcher = continueBreakVariable.matcher(this.val);
+        Matcher simpleVariableMatcher = simpleVariable.matcher(this.val);
+        
+        boolean matchFoundBoolean = booleanVariableMatcher.find();
+        boolean matchFoundContinueBreak = continueBreakVariableMatcher.find();
+        boolean matchFoundSimpleVariable = simpleVariableMatcher.find();
+
+        if (matchFoundBoolean) {
+            return new BoolType();
+        } else if (matchFoundContinueBreak) {
+            return new ContinueBreakType();
+        } else if (matchFoundSimpleVariable) {
+            return new AtomType(); // could be a variable or a fuction
+        } else {
+            return new VoidType(); // could be any type of data
+        }
     }
 
     // TODO: add code generation for atom node