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/*
 * SonarQube Java
 * Copyright (C) 2012-2025 SonarSource SA
 * mailto:info AT sonarsource DOT com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the Sonar Source-Available License Version 1, as published by SonarSource SA.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the Sonar Source-Available License for more details.
 *
 * You should have received a copy of the Sonar Source-Available License
 * along with this program; if not, see https://sonarsource.com/license/ssal/
 */
package org.sonar.java.checks;

import java.util.List;
import javax.annotation.Nullable;
import org.sonar.check.Rule;
import org.sonarsource.analyzer.commons.collections.ListUtils;
import org.sonar.plugins.java.api.IssuableSubscriptionVisitor;
import org.sonar.plugins.java.api.semantic.MethodMatchers;
import org.sonar.plugins.java.api.semantic.Symbol;
import org.sonar.plugins.java.api.semantic.Symbol.TypeSymbol;
import org.sonar.plugins.java.api.semantic.Type;
import org.sonar.plugins.java.api.tree.BaseTreeVisitor;
import org.sonar.plugins.java.api.tree.BlockTree;
import org.sonar.plugins.java.api.tree.ClassTree;
import org.sonar.plugins.java.api.tree.ExpressionStatementTree;
import org.sonar.plugins.java.api.tree.IdentifierTree;
import org.sonar.plugins.java.api.tree.LambdaExpressionTree;
import org.sonar.plugins.java.api.tree.MemberSelectExpressionTree;
import org.sonar.plugins.java.api.tree.MethodInvocationTree;
import org.sonar.plugins.java.api.tree.MethodTree;
import org.sonar.plugins.java.api.tree.StatementTree;
import org.sonar.plugins.java.api.tree.Tree;
import org.sonar.plugins.java.api.tree.TryStatementTree;
import org.sonarsource.analyzer.commons.annotations.DeprecatedRuleKey;

@DeprecatedRuleKey(ruleKey = "ObjectFinalizeOverridenCallsSuperFinalizeCheck", repositoryKey = "squid")
@Rule(key = "S1114")
public class ObjectFinalizeOverriddenCallsSuperFinalizeCheck extends IssuableSubscriptionVisitor {

  private static final String FINALIZE = "finalize";
  private static final MethodMatchers FINALIZE_MATCHER = MethodMatchers.create()
    .ofAnyType().names(FINALIZE).addWithoutParametersMatcher().build();

  @Override
  public List nodesToVisit() {
    return List.of(Tree.Kind.METHOD);
  }

  @Override
  public void visitNode(Tree tree) {

    MethodTree methodTree = (MethodTree) tree;
    if (isFinalizeOverriddenMethod(methodTree)) {
      BlockTree blockTree = methodTree.block();
      if (blockTree != null) {
        MethodInvocationTree lastSuperFinalizeInvocation = findLastSuperFinalizeInvocation(blockTree);
        if (lastSuperFinalizeInvocation == null) {
          reportIssue(methodTree.simpleName(), "Add a call to super.finalize() at the end of this Object.finalize() implementation.");
        } else if (!isLastStatement(blockTree, lastSuperFinalizeInvocation)) {
          reportIssue(lastSuperFinalizeInvocation, "Move this super.finalize() call to the end of this Object.finalize() implementation.");
        }
      }
    }
  }

  private static boolean isFinalizeOverriddenMethod(MethodTree methodTree) {
    return FINALIZE_MATCHER.matches(methodTree) && doesOverrideFinalize((TypeSymbol) methodTree.symbol().owner());
  }

  private static boolean doesOverrideFinalize(TypeSymbol typeSymbol) {
    Type superClassType = typeSymbol.superClass();
    while (superClassType != null && !superClassType.is("java.lang.Object")) {
      Symbol.TypeSymbol currentClass = superClassType.symbol();
      if (currentClass.lookupSymbols(FINALIZE).stream().anyMatch(FINALIZE_MATCHER::matches)) {
        return true;
      }
      superClassType = currentClass.superClass();
    }
    return false;
  }

  @Nullable
  private static MethodInvocationTree findLastSuperFinalizeInvocation(BlockTree blockTree) {
    FindLastSuperFinalizeInvocationVisitor visitor = new FindLastSuperFinalizeInvocationVisitor();
    blockTree.accept(visitor);
    return visitor.lastSuperFinalizeInvocation;
  }

  private static boolean isLastStatement(BlockTree blockTree, MethodInvocationTree lastStatementTree) {
    if (blockTree.body().stream().anyMatch(statement ->
      statement.is(Tree.Kind.TRY_STATEMENT) && isLastStatementInner(((TryStatementTree) statement).finallyBlock(), lastStatementTree)
    )) {
      return true;
    }
    return isLastStatementInner(blockTree, lastStatementTree);
  }

  private static boolean isLastStatementInner(@Nullable BlockTree blockTree, MethodInvocationTree lastStatementTree) {
    if (blockTree != null) {
      StatementTree last = ListUtils.getLast(blockTree.body());
      if (last.is(Tree.Kind.EXPRESSION_STATEMENT)) {
        return lastStatementTree.equals(((ExpressionStatementTree) last).expression());
      } else if (last.is(Tree.Kind.TRY_STATEMENT)) {
        return isLastStatementInner(((TryStatementTree) last).finallyBlock(), lastStatementTree);
      }
    }
    return false;
  }

  private static class FindLastSuperFinalizeInvocationVisitor extends BaseTreeVisitor {

    @Nullable
    public MethodInvocationTree lastSuperFinalizeInvocation;

    @Override
    public void visitMethodInvocation(MethodInvocationTree tree) {
      if (tree.methodSelect().is(Tree.Kind.MEMBER_SELECT)) {
        MemberSelectExpressionTree mset = (MemberSelectExpressionTree) tree.methodSelect();
        if (FINALIZE.equals(mset.identifier().name()) && mset.expression().is(Tree.Kind.IDENTIFIER) && "super".equals(((IdentifierTree) mset.expression()).name())) {
          lastSuperFinalizeInvocation = tree;
        }
      }
    }

    @Override
    public void visitClass(ClassTree tree) {
      // cut analysis on inner and anonymous classes, because we want to analyze actual control flow of finalize method only
    }

    @Override
    public void visitLambdaExpression(LambdaExpressionTree lambdaExpressionTree) {
      // cut analysis on lambda function bodies, because we want to analyze actual control flow of finalize method only
    }
  }
}