/*
    * 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.ExpandableProperty;
  import com.atlassian.jira.rest.client.RestClientException;
  import com.atlassian.jira.rest.client.domain.BasicUser;
  import org.codehaus.jettison.json.JSONArray;
  import org.codehaus.jettison.json.JSONException;
  import org.codehaus.jettison.json.JSONObject;
  import org.joda.time.DateTime;
  import org.joda.time.format.DateTimeFormatter;
  import org.joda.time.format.ISODateTimeFormat;
  
  import javax.annotation.Nullable;
  import java.net.URI;
  import java.net.URISyntaxException;
  import java.util.ArrayList;
  import java.util.Collection;
  
  public class JsonParseUtil {
  	private static final DateTimeFormatter DATE_TIME_FORMATTER = ISODateTimeFormat.dateTime();
  	private static final DateTimeFormatter DATE_FORMATTER = ISODateTimeFormat.date();
      public static final String VALUE_KEY = "value";
  	public static final String SELF_ATTR = "self";
  
  //	public interface ExpandablePropertyBuilder<T> {
  //		T parse(JSONObject json) throws JSONException;
  //	}
  
      public static <T> Collection<T> parseJsonArray(JSONArray jsonArray, JsonParser<T> jsonParser) throws JSONException {
          final Collection<T> res = new ArrayList<T>(jsonArray.length());
          for (int i = 0; i < jsonArray.length(); i++) {
              res.add(jsonParser.parse(jsonArray.getJSONObject(i)));
          }
          return res;
      }
      
  	public static <T> ExpandableProperty<T> parseExpandableProperty(JSONObject json, JsonParser<T> expandablePropertyBuilder)
  			throws JSONException {
  		final int numItems = json.getInt("size");
  		final Collection<T> items;
  		JSONArray itemsJa = json.getJSONArray("items");
  
  		if (itemsJa.length() > 0) {
  			items = new ArrayList<T>(numItems);
  			for (int i = 0; i < itemsJa.length(); i++) {
  				final T item = expandablePropertyBuilder.parse(itemsJa.getJSONObject(i));
  				items.add(item);
  			}
  		} else {
  			items = null;
  		}
  
  		return new ExpandableProperty<T>(numItems, items);
  	}
  
  
  
  	public static URI getSelfUri(JSONObject jsonObject) throws JSONException {
  		return parseURI(jsonObject.getString(SELF_ATTR));
  	}
  
  	public static JSONObject getNestedObject(JSONObject json, String... path) throws JSONException {
  		for (String s : path) {
  			json = json.getJSONObject(s);
  		}
  		return json;
  	}
  
      @Nullable
      public static JSONObject getNestedOptionalObject(JSONObject json, String... path) throws JSONException {
          for (int i = 0; i < path.length - 1; i++) {
              String s = path[i];
              json = json.getJSONObject(s);
          }
          return json.optJSONObject(path[path.length - 1]);
      }
  
  
  	public static JSONArray getNestedArray(JSONObject json, String... path) throws JSONException {
  		for (int i = 0; i < path.length - 1; i++) {
  			String s = path[i];
  			json = json.getJSONObject(s);
  		}
 		return json.getJSONArray(path[path.length - 1]);
 	}
 
     public static JSONArray getNestedOptionalArray(JSONObject json, String... path) throws JSONException {
         for (int i = 0; i < path.length - 1; i++) {
             String s = path[i];
             json = json.getJSONObject(s);
         }
         return json.optJSONArray(path[path.length - 1]);
     }
 
 
 	public static String getNestedString(JSONObject json, String... path) throws JSONException {
 
 		for (int i = 0; i < path.length - 1; i++) {
 			String s = path[i];
 			json = json.getJSONObject(s);
 		}
 		return json.getString(path[path.length - 1]);
 	}
 
     public static boolean getNestedBoolean(JSONObject json, String... path) throws JSONException {
 
         for (int i = 0; i < path.length - 1; i++) {
             String s = path[i];
             json = json.getJSONObject(s);
         }
         return json.getBoolean(path[path.length - 1]);
     }
 
 
 	public static URI parseURI(String str) {
 		try {
 			return new URI(str);
 		} catch (URISyntaxException e) {
 			throw new RestClientException(e);
 		}
 	}
 
 	@Nullable
 	public static URI parseOptionalURI(JSONObject jsonObject, String attributeName) {
 		final String s = getOptionalString(jsonObject, attributeName);
 		return s != null ? parseURI(s) : null;
 	}
 
 	@Nullable
 	public static BasicUser parseBasicUser(@Nullable JSONObject json) throws JSONException {
 		if (json == null) {
 			return null;
 		}
 		final String username = json.getString("name");
 		if (!json.has(JsonParseUtil.SELF_ATTR) && "Anonymous".equals(username)) {
 			return null; // insane representation for unassigned user - JRADEV-4262
 		}
 		return new BasicUser(getSelfUri(json), username, json.optString("displayName", null));
 	}
 
 	public static DateTime parseDateTime(JSONObject jsonObject, String attributeName) throws JSONException {
 		return parseDateTime(jsonObject.getString(attributeName));
 	}
 
 	@Nullable
 	public static DateTime parseOptionalDateTime(JSONObject jsonObject, String attributeName) throws JSONException {
 		final String s = getOptionalString(jsonObject, attributeName);
 		return s != null ? parseDateTime(s) : null;
 	}
 
 	public static DateTime parseDateTime(String str) {
 		try {
 			return DATE_TIME_FORMATTER.parseDateTime(str);
 		} catch (Exception e) {
 			throw new RestClientException(e);
 		}
 	}
 
 	public static DateTime parseDate(String str) {
 		try {
 			return DATE_FORMATTER.parseDateTime(str);
 		} catch (Exception e) {
 			throw new RestClientException(e);
 		}
 	}
 
 	public static String format(DateTime dateTime) {
 		return DATE_FORMATTER.print(dateTime);
 	}
 
 
 	@Nullable
 	public static String getNullableString(JSONObject jsonObject, String attributeName) throws JSONException {
 		final Object o = jsonObject.get(attributeName);
 		if (o == JSONObject.NULL) {
 			return null;
 		}
 		return o.toString();
 	}
 
 
     @Nullable
     public static String getOptionalString(JSONObject jsonObject, String attributeName) {
 		final Object res = jsonObject.opt(attributeName);
 		if (res == JSONObject.NULL || res == null) {
 			return null;
 		}
 		return res.toString();
     }
 
 	@Nullable
 	public static JSONObject getOptionalJsonObject(JSONObject jsonObject, String attributeName) {
 		final JSONObject res = jsonObject.optJSONObject(attributeName);
 		if (res == JSONObject.NULL || res == null) {
 			return null;
 		}
 		return res;
 	}
 
 
 	public static Collection<String> toStringCollection(JSONArray jsonArray) throws JSONException {
 		final ArrayList<String> res = new ArrayList<String>(jsonArray.length());
 		for (int i = 0; i < jsonArray.length(); i++) {
 			res.add(jsonArray.getString(i));
 		}
 		return res;
 	}
 
 	public static Integer parseOptionInteger(JSONObject json, final String attributeName) throws JSONException {
 		return json.has(attributeName) ? json.getInt(attributeName) : null;
 	}
 }