/**
 * Copyright (c) 2017-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */

package com.facebook.litho.specmodels.model;

import java.util.ArrayList;
import java.util.List;

import com.facebook.litho.annotations.OnCreateTreeProp;

import com.squareup.javapoet.TypeName;

class TreePropValidation {

  static List<SpecModelValidationError> validate(SpecModel specModel) {
    List<SpecModelValidationError> validationErrors = new ArrayList<>();

    final List<DelegateMethodModel> onCreateTreePropMethods =
        SpecModelUtils.getMethodModelsWithAnnotation(specModel, OnCreateTreeProp.class);
    for (DelegateMethodModel onCreateTreePropMethod : onCreateTreePropMethods) {
      if (onCreateTreePropMethod.returnType.equals(TypeName.VOID)) {
        validationErrors.add(
            new SpecModelValidationError(
                onCreateTreePropMethod.representedObject,
                "@OnCreateTreeProp methods cannot return void."));
      }

      if (onCreateTreePropMethod.returnType.isPrimitive() ||
          onCreateTreePropMethod.returnType.toString().startsWith("java.lang.") ||
          onCreateTreePropMethod.returnType.toString().startsWith("java.util.")) {
        validationErrors.add(
            new SpecModelValidationError(
                onCreateTreePropMethod.representedObject,
                "Returning a common JAVA class or a primitive is against the design" +
                    "of tree props, as they will be keyed on their specific types. Consider " +
                    "creating your own wrapper classes instead."));
      }

      if (onCreateTreePropMethod.methodParams.isEmpty() ||
          !onCreateTreePropMethod.methodParams.get(0).getType()
              .equals(specModel.getContextClass())) {
        validationErrors.add(
            new SpecModelValidationError(
                onCreateTreePropMethod.representedObject,
                "The first argument of an @OnCreateTreeProp method should be " +
                    specModel.getComponentClass() + "."));
      }
    }

    return validationErrors;
  }
}