refactor(diagnostics): enhance MagicDateDiagnostic with improved patterns and constants

- Introduced a new digitsPattern for better date validation in the isValidDateString method, enhancing clarity and maintainability.
- Replaced hardcoded navigation levels with constants for method calls and assignments, improving code readability and reducing magic numbers.
- Updated variable declarations to use 'var' for better type inference and cleaner code.

Author: johnnyshut

src/main/java/com/github/_1c_syntax/bsl/languageserver/diagnostics/MagicDateDiagnostic.java

@@ -22,7 +22,6 @@
 package com.github._1c_syntax.bsl.languageserver.diagnostics;
 
 import com.github._1c_syntax.bsl.languageserver.context.symbol.SymbolTree;
-import com.github._1c_syntax.bsl.languageserver.context.symbol.VariableSymbol;
 import com.github._1c_syntax.bsl.languageserver.diagnostics.metadata.DiagnosticMetadata;
 import com.github._1c_syntax.bsl.languageserver.diagnostics.metadata.DiagnosticParameter;
 import com.github._1c_syntax.bsl.languageserver.diagnostics.metadata.DiagnosticSeverity;
@@ -36,6 +35,7 @@
 
 import java.util.Arrays;
 import java.util.HashSet;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
@@ -91,6 +91,8 @@ public class MagicDateDiagnostic extends AbstractVisitorDiagnostic {
     "\\D"
   );
 
+  private static final Pattern digitsPattern = Pattern.compile("\\d+");
+  
   private static final Pattern STRUCTURE_METHOD_PATTERN = CaseInsensitivePattern.compile(
     "(?i)Вставить|Insert"
   );
@@ -106,6 +108,8 @@ public class MagicDateDiagnostic extends AbstractVisitorDiagnostic {
   private static final int MAX_SECOND = 59;
   private static final int DATE_LENGTH = 8;
   private static final int DATETIME_LENGTH = 14;
+  private static final int NAVIGATION_LEVELS_TO_METHOD_CALL = 4;
+  private static final int NAVIGATION_LEVELS_TO_ASSIGNMENT = 4;
 
   @DiagnosticParameter(
     type = String.class,
@@ -146,7 +150,7 @@ public void configure(Map<String, Object> configuration) {
    * @return true, если строка является валидной датой, иначе false
    */
   private static boolean isValidDateString(String dateString) {
-    return dateString.matches("\\d+") && (dateString.length() == DATE_LENGTH || dateString.length() == DATETIME_LENGTH);
+    return digitsPattern.matcher(dateString).matches() && (dateString.length() == DATE_LENGTH || dateString.length() == DATETIME_LENGTH);
   }
 
 
@@ -331,7 +335,7 @@ private static boolean insideReturnSimpleDate(BSLParser.ExpressionContext expres
    * @return true, если выражение находится внутри присваивания с методом Дата(), иначе false
    */
   private static boolean insideAssignmentWithDateMethodForSimpleDate(BSLParser.ExpressionContext expression) {
-    BSLParserRuleContext current = navigateToParent(expression, 4);
+    BSLParserRuleContext current = navigateToParent(expression, NAVIGATION_LEVELS_TO_METHOD_CALL);
     if (!(current instanceof BSLParser.GlobalMethodCallContext)) {
       return false;
     }
@@ -341,7 +345,7 @@ private static boolean insideAssignmentWithDateMethodForSimpleDate(BSLParser.Exp
       return false;
     }
 
-    current = navigateToParent(current, 4);
+    current = navigateToParent(current, NAVIGATION_LEVELS_TO_ASSIGNMENT);
     return current instanceof BSLParser.AssignmentContext;
   }
 
@@ -353,7 +357,7 @@ private static boolean insideAssignmentWithDateMethodForSimpleDate(BSLParser.Exp
    * @return родительский контекст или null, если навигация невозможна
    */
   private static BSLParserRuleContext navigateToParent(BSLParserRuleContext context, int levels) {
-    BSLParserRuleContext current = context;
+    var current = context;
     for (int i = 0; i < levels; i++) {
       if (current == null) {
         return null;
@@ -413,7 +417,7 @@ private boolean isStructureMethodCall(BSLParser.ExpressionContext expr) {
       return false;
     }
 
-    String callText = callStatement.getText();
+    var callText = callStatement.getText();
     if (!isValidCallText(callText)) {
       return false;
     }
@@ -432,14 +436,14 @@ private boolean isStructureMethodCall(BSLParser.ExpressionContext expr) {
    * @return true, если это вызов метода структуры, иначе false
    */
   private boolean isStructureObjectCall(String callText) {
-    int dotIndex = callText.indexOf('.');
-    String objectName = callText.substring(0, dotIndex).trim();
-    String methodPart = callText.substring(dotIndex + 1);
+    var dotIndex = callText.indexOf('.');
+    var methodPart = callText.substring(dotIndex + 1);
 
     if (!STRUCTURE_METHOD_PATTERN.matcher(methodPart).find()) {
       return false;
     }
 
+    var objectName = callText.substring(0, dotIndex).trim();
     return isVariableOfStructureType(objectName);
   }
 
@@ -450,7 +454,7 @@ private boolean isStructureObjectCall(String callText) {
    * @return true, если текст валиден, иначе false
    */
   private static boolean isValidCallText(String callText) {
-    int dotIndex = callText.indexOf('.');
+    var dotIndex = callText.indexOf('.');
     return dotIndex > 0 && callText.contains("(");
   }
 
@@ -470,8 +474,8 @@ private boolean isVariableOfStructureType(String variableName) {
 
     return variableSymbol.get().getDescription()
       .map(description -> description.getDescription())
-      .map(description -> {
-        var lowerDescription = description.toLowerCase();
+      .map((String description) -> {
+        var lowerDescription = description.toLowerCase(Locale.ROOT);
         return lowerDescription.contains("структура") || lowerDescription.contains("structure");
       })
       .orElse(false);