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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 org.apache.commons.lang3.StringUtils;
import org.sonar.check.Rule;
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.Type;
import org.sonar.plugins.java.api.tree.ExpressionTree;
import org.sonar.plugins.java.api.tree.IdentifierTree;
import org.sonar.plugins.java.api.tree.MemberSelectExpressionTree;
import org.sonar.plugins.java.api.tree.MethodInvocationTree;
import org.sonar.plugins.java.api.tree.NewClassTree;
import org.sonar.plugins.java.api.tree.Tree;
import org.sonar.plugins.java.api.tree.VariableTree;

import java.util.Arrays;
import java.util.List;

@Rule(key = "S2130")
public class StringToPrimitiveConversionCheck extends IssuableSubscriptionVisitor {

  private final List primitiveChecks = buildPrimitiveChecks();

  @Override
  public List nodesToVisit() {
    return Arrays.asList(Tree.Kind.VARIABLE, Tree.Kind.METHOD_INVOCATION);
  }

  @Override
  public void visitNode(Tree tree) {
    if (tree.is(Tree.Kind.VARIABLE)) {
      VariableTree variableTree = (VariableTree) tree;
      Type variableType = variableTree.type().symbolType();
      PrimitiveCheck primitiveCheck = getPrimitiveCheck(variableType);
      ExpressionTree initializer = variableTree.initializer();
      if (primitiveCheck != null && initializer != null) {
        primitiveCheck.checkInstantiation(initializer);
      }
    } else {
      MethodInvocationTree methodInvocationTree = (MethodInvocationTree) tree;
      for (PrimitiveCheck primitiveCheck : primitiveChecks) {
        primitiveCheck.checkMethodInvocation(methodInvocationTree);
      }
    }
  }

  private PrimitiveCheck getPrimitiveCheck(Type type) {
    if (!type.isPrimitive()) {
      return null;
    }
    for (PrimitiveCheck primitiveCheck : primitiveChecks) {
      if (type.isPrimitive(primitiveCheck.tag)) {
        return primitiveCheck;
      }
    }
    return null;
  }

  private List buildPrimitiveChecks() {
    return Arrays.asList(
      new PrimitiveCheck("int", "Integer", Type.Primitives.INT),
      new PrimitiveCheck("boolean", "Boolean", Type.Primitives.BOOLEAN),
      new PrimitiveCheck("byte", "Byte", Type.Primitives.BYTE),
      new PrimitiveCheck("double", "Double", Type.Primitives.DOUBLE),
      new PrimitiveCheck("float", "Float", Type.Primitives.FLOAT),
      new PrimitiveCheck("long", "Long", Type.Primitives.LONG),
      new PrimitiveCheck("short", "Short", Type.Primitives.SHORT));
  }

  private class PrimitiveCheck {
    private final String primitiveName;
    private final String className;
    private final Type.Primitives tag;
    private final String message;
    private final MethodMatchers unboxingInvocationMatcher;
    private final MethodMatchers valueOfInvocationMatcher;

    private PrimitiveCheck(String primitiveName, String className, Type.Primitives tag) {
      this.primitiveName = primitiveName;
      this.className = className;
      this.tag = tag;
      this.message = "Use \"" + parseMethodName() + "\" for this string-to-" + primitiveName + " conversion.";
      this.unboxingInvocationMatcher = MethodMatchers.create()
        .ofTypes("java.lang." + className)
        .names(primitiveName + "Value")
        .addWithoutParametersMatcher()
        .build();
      this.valueOfInvocationMatcher = MethodMatchers.create()
        .ofTypes("java.lang." + className)
        .names("valueOf")
        .addParametersMatcher("java.lang.String")
        .build();
    }

    private void checkMethodInvocation(MethodInvocationTree methodInvocationTree) {
      if (unboxingInvocationMatcher.matches(methodInvocationTree)) {
        MemberSelectExpressionTree methodSelect = (MemberSelectExpressionTree) methodInvocationTree.methodSelect();
        checkInstantiation(methodSelect.expression());
      }
    }

    private void checkInstantiation(ExpressionTree expression) {
      if (isBadlyInstantiated(expression)) {
        reportIssue(expression, message);
      }
    }

    private boolean isBadlyInstantiated(ExpressionTree expression) {
      boolean result = false;
      if (expression.is(Tree.Kind.NEW_CLASS)) {
        result = isStringBasedConstructor((NewClassTree) expression);
      } else if (expression.is(Tree.Kind.METHOD_INVOCATION)) {
        result = valueOfInvocationMatcher.matches((MethodInvocationTree) expression);
      } else if (expression.is(Tree.Kind.IDENTIFIER)) {
        IdentifierTree identifier = (IdentifierTree) expression;
        Symbol reference = identifier.symbol();
        if (reference.isVariableSymbol() && reference.usages().size() == 1) {
          Symbol.VariableSymbol variableSymbol = (Symbol.VariableSymbol) reference;
          result = isBadlyInstantiatedVariable(variableSymbol);
        }
      }
      return result;
    }

    private boolean isBadlyInstantiatedVariable(Symbol.VariableSymbol variableSymbol) {
      VariableTree variableTree = variableSymbol.declaration();
      if (variableTree != null) {
        ExpressionTree initializer = variableTree.initializer();
        if (initializer != null) {
          return isBadlyInstantiated(initializer);
        }
      }
      return false;
    }

    private boolean isStringBasedConstructor(NewClassTree newClassTree) {
      List arguments = newClassTree.arguments();
      return arguments.get(0).symbolType().is("java.lang.String");
    }

    private String parseMethodName() {
      return className + ".parse" + StringUtils.capitalize(primitiveName);
    }
  }

}