// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
package com.intellij.psi.impl.source.tree.java;

import com.intellij.lang.ASTNode;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.psi.*;
import com.intellij.psi.impl.source.Constants;
import com.intellij.psi.impl.source.tree.ChildRole;
import com.intellij.psi.tree.ChildRoleBase;
import com.intellij.psi.tree.IElementType;
import com.intellij.psi.util.PsiUtil;
import org.jetbrains.annotations.NotNull;

public class PsiArrayAccessExpressionImpl extends ExpressionPsiElement implements PsiArrayAccessExpression, Constants {
  private static final Logger LOG = Logger.getInstance(PsiArrayAccessExpressionImpl.class);

  public PsiArrayAccessExpressionImpl() {
    super(ARRAY_ACCESS_EXPRESSION);
  }

  @Override
  public @NotNull PsiExpression getArrayExpression() {
    return (PsiExpression)findChildByRoleAsPsiElement(ChildRole.ARRAY);
  }

  @Override
  public PsiExpression getIndexExpression() {
    return (PsiExpression)findChildByRoleAsPsiElement(ChildRole.INDEX);
  }

  @Override
  public PsiType getType() {
    PsiType arrayType = getArrayExpression().getType();
    if (!(arrayType instanceof PsiArrayType)) return null;
    final PsiType componentType = ((PsiArrayType)arrayType).getComponentType();
    if (PsiUtil.isAccessedForWriting(this)) return componentType;
    return PsiUtil.captureToplevelWildcards(componentType, this);
  }

  @Override
  public ASTNode findChildByRole(int role) {
    LOG.assertTrue(ChildRole.isUnique(role));
    switch(role){
      case ChildRole.ARRAY:
        return getFirstChildNode();

      case ChildRole.INDEX:
        {
          ASTNode lbracket = findChildByRole(ChildRole.LBRACKET);
          if (lbracket == null) return null;
          for(ASTNode child = lbracket.getTreeNext(); child != null; child = child.getTreeNext()){
            if (EXPRESSION_BIT_SET.contains(child.getElementType())){
              return child;
            }
          }
          return null;
        }

      case ChildRole.LBRACKET:
        return findChildByType(LBRACKET);

      case ChildRole.RBRACKET:
        return findChildByType(RBRACKET);

      default:
        return null;
    }
  }

  @Override
  public int getChildRole(@NotNull ASTNode child) {
    LOG.assertTrue(child.getTreeParent() == this);
    IElementType i = child.getElementType();
    if (i == LBRACKET) {
      return ChildRole.LBRACKET;
    }
    else if (i == RBRACKET) {
      return ChildRole.RBRACKET;
    }
    else {
      if (EXPRESSION_BIT_SET.contains(child.getElementType())) {
        return child == getFirstChildNode() ? ChildRole.ARRAY : ChildRole.INDEX;
      }
      else {
        return ChildRoleBase.NONE;
      }
    }
  }

  @Override
  public void accept(@NotNull PsiElementVisitor visitor) {
    if (visitor instanceof JavaElementVisitor) {
      ((JavaElementVisitor)visitor).visitArrayAccessExpression(this);
    }
    else {
      visitor.visitElement(this);
    }
  }

  @Override
  public String toString() {
    return "PsiArrayAccessExpression:" + getText();
  }
}

