// Copyright (c) 2023, the R8 project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

package com.android.tools.r8.graph.lens;

import com.android.tools.r8.errors.Unreachable;
import com.android.tools.r8.graph.DexField;
import com.android.tools.r8.graph.DexItemFactory;
import com.android.tools.r8.graph.DexMethod;
import com.android.tools.r8.graph.DexType;
import com.android.tools.r8.graph.proto.RewrittenPrototypeDescription;
import com.android.tools.r8.ir.code.InvokeType;

// This lens clears all code rewriting (lookup methods mimics identity lens behavior) but still
// relies on the previous lens for names (getRenamed/Original methods).
public class ClearCodeRewritingGraphLens extends NonIdentityGraphLens {

  public ClearCodeRewritingGraphLens(DexItemFactory dexItemFactory, GraphLens previousLens) {
    super(dexItemFactory, previousLens);
  }

  @Override
  public DexType getOriginalType(DexType type) {
    return getPrevious().getOriginalType(type);
  }

  @Override
  public Iterable<DexType> getOriginalTypes(DexType type) {
    return getPrevious().getOriginalTypes(type);
  }

  @Override
  public DexField getOriginalFieldSignature(DexField field) {
    return getPrevious().getOriginalFieldSignature(field);
  }

  @Override
  public DexField getRenamedFieldSignature(DexField originalField, GraphLens codeLens) {
    return this != codeLens ? getPrevious().getRenamedFieldSignature(originalField) : originalField;
  }

  @Override
  public DexMethod getRenamedMethodSignature(DexMethod originalMethod, GraphLens applied) {
    return this != applied
        ? getPrevious().getRenamedMethodSignature(originalMethod, applied)
        : originalMethod;
  }

  @Override
  public boolean isClearCodeRewritingLens() {
    return true;
  }

  @Override
  public RewrittenPrototypeDescription lookupPrototypeChangesForMethodDefinition(
      DexMethod method, GraphLens codeLens) {
    return getIdentityLens().lookupPrototypeChangesForMethodDefinition(method, codeLens);
  }

  @Override
  public final DexType internalDescribeLookupClassType(DexType previous) {
    return previous;
  }

  @Override
  protected FieldLookupResult internalLookupField(
      DexField reference, GraphLens codeLens, LookupFieldContinuation continuation) {
    return getIdentityLens().internalLookupField(reference, codeLens, continuation);
  }

  @Override
  protected FieldLookupResult internalDescribeLookupField(FieldLookupResult previous) {
    throw new Unreachable();
  }

  @Override
  protected MethodLookupResult internalLookupMethod(
      DexMethod reference,
      DexMethod context,
      InvokeType type,
      GraphLens codeLens,
      LookupMethodContinuation continuation) {
    assert codeLens == null || codeLens == this;
    GraphLens identityLens = getIdentityLens();
    return identityLens.internalLookupMethod(reference, context, type, identityLens, continuation);
  }

  @Override
  public MethodLookupResult internalDescribeLookupMethod(
      MethodLookupResult previous, DexMethod context) {
    throw new Unreachable();
  }

  @Override
  public DexMethod getPreviousMethodSignature(DexMethod method) {
    return method;
  }

  @Override
  public DexMethod getNextMethodSignature(DexMethod method) {
    return method;
  }

  @Override
  public boolean isContextFreeForMethods() {
    return getIdentityLens().isContextFreeForMethods();
  }
}