/*
    * Copyright (C) 2010 Atlassian
    *
    * 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 com.atlassian.jira.rest.client.internal.json;
  
  import com.atlassian.jira.rest.client.api.domain.BasicUser;
  import com.atlassian.jira.rest.client.api.domain.IssueField;
  import org.codehaus.jettison.json.JSONException;
  import org.codehaus.jettison.json.JSONObject;
  
  import java.util.HashMap;
  import java.util.Map;
  
  public class IssueFieldJsonParser {
      private static final String VALUE_ATTRIBUTE = "value";
  
      private Map<String, JsonObjectParser> registeredValueParsers = new HashMap<String, JsonObjectParser>() {{
          put("com.atlassian.jira.plugin.system.customfieldtypes:float", new FloatingPointFieldValueParser());
          put("com.atlassian.jira.plugin.system.customfieldtypes:userpicker", new FieldValueJsonParser<BasicUser>(new BasicUserJsonParser()));
          put("java.lang.String", new StringFieldValueParser());
      }};
  
      @SuppressWarnings("unchecked")
      public IssueField parse(JSONObject jsonObject, String id) throws JSONException {
          String type = jsonObject.getString("type");
          final String name = jsonObject.getString("name");
          final Object valueObject = jsonObject.opt(VALUE_ATTRIBUTE);
          final Object value;
          // @todo ugly hack until https://jdog.atlassian.com/browse/JRADEV-3220 is fixed
          if ("comment".equals(name)) {
              type = "com.atlassian.jira.Comment";
          }
  
          if (valueObject == null) {
              value = null;
          } else {
              final JsonObjectParser valueParser = registeredValueParsers.get(type);
              if (valueParser != null) {
                  value = valueParser.parse(jsonObject);
              } else {
                  value = valueObject.toString();
              }
          }
          return new IssueField(id, name, type, value);
      }
  
      static class FieldValueJsonParser<T> implements JsonObjectParser<T> {
          private final JsonObjectParser<T> jsonParser;
  
          public FieldValueJsonParser(JsonObjectParser<T> jsonParser) {
              this.jsonParser = jsonParser;
          }
  
          @Override
          public T parse(JSONObject json) throws JSONException {
              final JSONObject valueObject = json.optJSONObject(VALUE_ATTRIBUTE);
              if (valueObject == null) {
                  throw new JSONException("Expected JSONObject with [" + VALUE_ATTRIBUTE + "] attribute present.");
              }
              return jsonParser.parse(valueObject);
          }
      }
  
  
      static class FloatingPointFieldValueParser implements JsonObjectParser<Double> {
  
          @Override
          public Double parse(JSONObject jsonObject) throws JSONException {
              final String s = JsonParseUtil.getNullableString(jsonObject, VALUE_ATTRIBUTE);
              if (s == null) {
                  return null;
              }
              try {
                  return Double.parseDouble(s);
              } catch (NumberFormatException e) {
                  throw new JSONException("[" + s + "] is not a valid floating point number");
              }
          }
      }
  
      static class StringFieldValueParser implements JsonObjectParser<String> {
  
          @Override
          public String parse(JSONObject jsonObject) throws JSONException {
              return JsonParseUtil.getNullableString(jsonObject, VALUE_ATTRIBUTE);
          }
     }
 
 
 }