// Copyright (c) 2020, 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.tracereferences;

import com.android.tools.r8.Diagnostic;
import com.android.tools.r8.Keep;
import com.android.tools.r8.origin.Origin;
import com.android.tools.r8.position.Position;
import com.android.tools.r8.references.ClassReference;
import com.android.tools.r8.references.FieldReference;
import com.android.tools.r8.references.MethodReference;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;

@Keep
public class MissingDefinitionsDiagnostic implements Diagnostic {

  private final Set<ClassReference> missingClasses;
  private final Set<FieldReference> missingFields;
  private final Set<MethodReference> missingMethods;

  MissingDefinitionsDiagnostic(
      Set<ClassReference> missingClasses,
      Set<FieldReference> missingFields,
      Set<MethodReference> missingMethods) {
    this.missingClasses = missingClasses;
    this.missingFields = missingFields;
    this.missingMethods = missingMethods;
  }

  @Override
  public Origin getOrigin() {
    return Origin.unknown();
  }

  @Override
  public Position getPosition() {
    return Position.UNKNOWN;
  }

  private <T> void appendSorted(StringBuilder builder, Set<T> missing) {
    missing.stream()
        .map(Object::toString)
        .sorted()
        .forEach(item -> builder.append("  ").append(item).append(System.lineSeparator()));
  }

  public Set<ClassReference> getMissingClasses() {
    return missingClasses;
  }

  public Set<FieldReference> getMissingFields() {
    return missingFields;
  }

  public Set<MethodReference> getMissingMethods() {
    return missingMethods;
  }

  @Override
  public String getDiagnosticMessage() {
    StringBuilder builder = new StringBuilder("Tracereferences found ");
    List<String> components = new ArrayList<>();
    if (missingClasses.size() > 0) {
      components.add("" + missingClasses.size() + " classe(s)");
    }
    if (missingFields.size() > 0) {
      components.add("" + missingFields.size() + " field(s)");
    }
    if (missingMethods.size() > 0) {
      components.add("" + missingMethods.size() + " method(s)");
    }
    assert components.size() > 0;
    for (int i = 0; i < components.size(); i++) {
      if (i != 0) {
        builder.append(i < components.size() - 1 ? ", " : " and ");
      }
      builder.append(components.get(i));
    }
    builder.append(" without definition");
    builder.append(System.lineSeparator());
    builder.append(System.lineSeparator());
    if (missingClasses.size() > 0) {
      builder.append("Classe(s) without definition:" + System.lineSeparator());
      appendSorted(builder, missingClasses);
    }
    if (missingFields.size() > 0) {
      builder.append("Field(s) without definition:" + System.lineSeparator());
      appendSorted(builder, missingFields);
    }
    if (missingMethods.size() > 0) {
      builder.append("Method(s) without definition:" + System.lineSeparator());
      appendSorted(builder, missingMethods);
    }
    return builder.toString();
  }
}