Replace print/println keywords with generic function call mechanism

- Add NODE_CALL with name, args, and arg_count to parser
- Add TOK_COMMA token and tokenize (, ), , in lexer
- Remove TOK_PRINT/TOK_PRINTLN keywords; print/println are now regular
  identifiers resolved as built-in functions in the evaluator
- Add NODE_CALL debug output in ast_print

src/frontend/parser.h

@@ -17,6 +17,7 @@ typedef enum {
   NODE_IF,    // if cond: bloque
   NODE_WHILE, // while cond: bloque
   NODE_BLOCK, // secuencia de statements
+  NODE_CALL,
 } NodeType;
 
 typedef struct ASTNode {
@@ -48,6 +49,11 @@ typedef struct ASTNode {
       struct ASTNode *cond;
       struct ASTNode *body;
     } if_statement; // NODE_IF
+    struct {
+      char *name;
+      struct ASTNode **args;
+      int arg_count;
+    } call;
   } data;
 } ASTNode;
 
@@ -71,10 +77,13 @@ ASTNode *parse_term(Token *tokens) {
     pos++;
     return node;
   } else if (tokens[pos].type == TOK_ID) {
+    printf("Parsing token: %s\n", tokens[pos].value);
+
     ASTNode *node = make_node(NODE_VAR);
     node->data.string_val = tokens[pos].value;
     pos++;
     return node;
+
   } else if (tokens[pos].type == TOK_MINUS) {
     pos++; // consumir '-'
     ASTNode *term = parse_term(tokens);
@@ -85,7 +94,9 @@ ASTNode *parse_term(Token *tokens) {
     neg->data.binop.right = term;
     return neg;
   }
-  printf("ERROR: esperaba INT o ID, encontre tipo %d\n", tokens[pos].type);
+
+  printf("ERROR: esperaba INT o ID, encontre tipo %d value: %s\n",
+         tokens[pos].type, tokens[pos].value);
   exit(1);
 }
 
@@ -110,6 +121,32 @@ ASTNode *parse_expr(Token *tokens) {
 
 ASTNode *parse_statement(Token *tokens) {
   if (tokens[pos].type == TOK_ID) {
+    if (tokens[pos + 1].type == TOK_LPAREN) {
+      // Es una funcion
+      char *name = tokens[pos].value;
+      pos++; // consumir ID
+      pos++; // consumir "("
+
+      // Parsear argumentos
+      ASTNode **args =
+          (ASTNode **)malloc(sizeof(ASTNode *) * 16); // Max 16 parametros
+      int arg_count = 0;
+
+      if (tokens[pos].type != TOK_RPAREN) {
+        args[arg_count++] = parse_expr(tokens);
+        while (tokens[pos].type == TOK_COMMA) {
+          pos++; // Consumir ","
+          args[arg_count++] = parse_expr(tokens);
+        }
+      }
+      pos++; // consumir ")"
+      ASTNode *node = make_node(NODE_CALL);
+      node->data.call.name = name;
+      node->data.call.args = args;
+      node->data.call.arg_count = arg_count;
+      return node;
+    }
+
     char *name = tokens[pos].value;
     pos++; // consumir ID
     pos++; // consumir "="
@@ -120,23 +157,6 @@ ASTNode *parse_statement(Token *tokens) {
     node->data.assign.value = value;
     return node;
   }
-  if (tokens[pos].type == TOK_PRINT) {
-    pos++; // consumir "print"
-    ASTNode *expr = parse_expr(tokens);
-
-    ASTNode *node = make_node(NODE_PRINT);
-    node->data.print.expr = expr;
-    return node;
-  }
-
-  if (tokens[pos].type == TOK_PRINTLN) {
-    pos++; // consumir "println"
-    ASTNode *expr = parse_expr(tokens);
-
-    ASTNode *node = make_node(NODE_PRINTLN);
-    node->data.print.expr = expr;
-    return node;
-  }
 
   if (tokens[pos].type == TOK_WHILE) {
     pos++; // consumir while
@@ -257,16 +277,6 @@ void ast_print(ASTNode *node, const char *prefix, int is_last) {
     ast_print(node->data.binop.right, new_prefix, 1);
     break;
 
-  case NODE_PRINT:
-    printf("NODE_PRINT\n");
-    ast_print(node->data.print.expr, new_prefix, 1);
-    break;
-
-  case NODE_PRINTLN:
-    printf("NODE_PRINTLN\n");
-    ast_print(node->data.print.expr, new_prefix, 1);
-    break;
-
   case NODE_BLOCK:
     printf("NODE_BLOCK\n");
     for (int i = 0; i < node->data.block.count; i++) {
@@ -281,6 +291,14 @@ void ast_print(ASTNode *node, const char *prefix, int is_last) {
     ast_print(node->data.while_loop.body, new_prefix, 1);
     break;
 
+  case NODE_CALL:
+    printf("NODE_CALL(\"%s\")\n", node->data.call.name);
+    for (int i = 0; i < node->data.call.arg_count; i++) {
+      ast_print(node->data.call.args[i], new_prefix,
+                i == node->data.call.arg_count - 1);
+    }
+    break;
+
   default:
     printf("UNKNOWN\n");
     break;