/*
    * 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
    *
    * http://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.basepom.mojo.propertyhelper;
  
  import static com.google.common.base.Preconditions.checkNotNull;
  
  import org.basepom.mojo.propertyhelper.beans.IgnoreWarnFail;
  import org.basepom.mojo.propertyhelper.beans.StringDefinition;
  
  import java.io.IOException;
  import java.util.List;
  import java.util.Optional;
  
  import com.google.common.collect.ImmutableList;
  import com.google.common.collect.ImmutableList.Builder;
  import com.google.common.collect.Lists;
  
  public class StringField
          implements PropertyElement {
  
      private final StringDefinition stringDefinition;
      private final ValueProvider valueProvider;
  
      public StringField(final StringDefinition stringDefinition, final ValueProvider valueProvider) {
          this.stringDefinition = stringDefinition;
          this.valueProvider = valueProvider;
      }
  
      public static List<StringField> createStrings(final ValueCache valueCache, final StringDefinition... stringDefinitions)
              throws IOException {
          checkNotNull(valueCache, "valueCache is null");
  
          final Builder<StringField> result = ImmutableList.builder();
  
          for (StringDefinition stringDefinition : stringDefinitions) {
              stringDefinition.check();
              final ValueProvider stringValue = valueCache.getValueProvider(stringDefinition);
              final StringField stringField = new StringField(stringDefinition, stringValue);
              result.add(stringField);
          }
          return result.build();
      }
  
      @Override
      public String getPropertyName() {
          // This is not the property name (because many definitions can map onto one prop)
          // but the actual id.
          return stringDefinition.getId();
      }
  
      @Override
      public Optional<String> getPropertyValue() {
          final List<String> values = Lists.newArrayList();
  
          final Optional<String> propValue = valueProvider.getValue();
          final List<String> definedValues = stringDefinition.getValues();
  
          // Only add the value from the provider if it is not null.
          propValue.ifPresent(values::add);
  
          values.addAll(definedValues);
  
          for (String value : values) {
              if (stringDefinition.isBlankIsValid() || (value != null && !value.trim().isEmpty())) {
                  return stringDefinition.formatResult(value);
              }
          }
  
          IgnoreWarnFail.checkState(stringDefinition.getOnMissingValue(), false, "value");
  
          return Optional.empty();
      }
  
      @Override
      public boolean isExport() {
          return stringDefinition.isExport();
      }
  
      @Override
      public String toString() {
          return getPropertyValue().orElse("");
      }
  }