/*
    *    Copyright 2009-2023 the original author or authors.
    *
    *    Licensed under the Apache License, Version 2.0 (the "License");
    *    you may not use this file except in compliance with the License.
    *    You may obtain a copy of the License at
    *
    *       https://www.apache.org/licenses/LICENSE-2.0
    *
   *    Unless required by applicable law or agreed to in writing, software
   *    distributed under the License is distributed on an "AS IS" BASIS,
   *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *    See the License for the specific language governing permissions and
   *    limitations under the License.
   */
  package org.mybatis.guice.type;
  
  import com.google.inject.Injector;
  import com.google.inject.TypeLiteral;
  
  import jakarta.inject.Inject;
  import jakarta.inject.Provider;
  
  import java.lang.reflect.Constructor;
  import java.util.Objects;
  
  import org.apache.ibatis.type.TypeException;
  import org.apache.ibatis.type.TypeHandler;
  
  /**
   * A generic MyBatis type provider.
   */
  public final class TypeHandlerProvider<TH extends TypeHandler<? extends T>, T> implements Provider<TH> {
    private final TypeLiteral<TH> typeHandlerTypeLiteral;
    private final Class<T> handledType;
    @Inject
    private Injector injector;
  
    public TypeHandlerProvider(Class<TH> typeHandlerType, Class<T> handledType) {
      this.typeHandlerTypeLiteral = TypeLiteral.get(typeHandlerType);
      this.handledType = handledType;
    }
  
    public TypeHandlerProvider(TypeLiteral<TH> typeHandlerType, Class<T> handledType) {
      this.typeHandlerTypeLiteral = typeHandlerType;
      this.handledType = handledType;
    }
  
    TypeHandlerProvider(Injector injector, Class<TH> typeHandlerType, Class<T> handledType) {
      this(typeHandlerType, handledType);
      this.injector = injector;
    }
  
    TypeHandlerProvider(Injector injector, TypeLiteral<TH> typeHandlerType, Class<T> handledType) {
      this(typeHandlerType, handledType);
      this.injector = injector;
    }
  
    @Override
    @SuppressWarnings("unchecked")
    public TH get() {
      TH instance = null;
      if (handledType != null) {
        try {
          Constructor<?> c = typeHandlerTypeLiteral.getRawType().getConstructor(Class.class);
          instance = (TH) c.newInstance(handledType);
          injector.injectMembers(instance);
        } catch (NoSuchMethodException ignored) {
          // ignored
        } catch (Exception e) {
          throw new TypeException("Failed invoking constructor for handler " + typeHandlerTypeLiteral.getType(), e);
        }
      }
      if (instance == null) {
        try {
          instance = (TH) typeHandlerTypeLiteral.getRawType().newInstance();
          injector.injectMembers(instance);
        } catch (Exception e) {
          throw new TypeException("Failed invoking constructor for handler " + typeHandlerTypeLiteral.getType(), e);
        }
      }
      return instance;
    }
  
    @Override
    public int hashCode() {
      return Objects.hash(this.typeHandlerTypeLiteral, this.handledType);
    }
  
    @Override
    public boolean equals(Object obj) {
      if (obj == null) {
        return false;
      }
      if (this.getClass() != obj.getClass()) {
        return false;
      }
      TypeHandlerProvider other = (TypeHandlerProvider) obj;
      return Objects.equals(this.typeHandlerTypeLiteral, other.typeHandlerTypeLiteral)
         && Objects.equals(this.handledType, other.handledType);
   }
 }