/*
    * 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.OptionalIterable;
  import com.atlassian.jira.rest.client.RestClientException;
  import com.atlassian.jira.rest.client.domain.BasicUser;
  import com.google.common.base.Optional;
  import com.google.common.collect.Maps;
  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.DateTimeFormat;
  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;
  import java.util.Iterator;
  import java.util.Map;
  
  public class JsonParseUtil {
  	public static final String JIRA_DATE_TIME_PATTERN = "yyyy-MM-dd'T'HH:mm:ss.SSSZ";
  	public static final DateTimeFormatter JIRA_DATE_TIME_FORMATTER = DateTimeFormat.forPattern(JIRA_DATE_TIME_PATTERN);
  	public static final DateTimeFormatter JIRA_DATE_FORMATTER = ISODateTimeFormat.date();
  	public static final String SELF_ATTR = "self";
  
      public static <T> Collection<T> parseJsonArray(JSONArray jsonArray, JsonObjectParser<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> OptionalIterable<T> parseOptionalJsonArray(JSONArray jsonArray, JsonObjectParser<T> jsonParser)
  			throws JSONException {
  		if (jsonArray == null) {
  			return OptionalIterable.absent();
  		}
  		else {
  			return new OptionalIterable<T>(JsonParseUtil.<T>parseJsonArray(jsonArray, jsonParser));
  		}
  	}
      
  	public static <T> ExpandableProperty<T> parseExpandableProperty(JSONObject json, JsonObjectParser<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 URI optSelfUri(JSONObject jsonObject, URI defaultUri) throws JSONException {
  		final String selfUri = jsonObject.optString(SELF_ATTR, null);
  		return selfUri != null ? parseURI(selfUri) : defaultUri;
  	}
  
  	@SuppressWarnings("unused")
  	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]);
     }
 
 	@SuppressWarnings("unused")
 	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; json != null && i < path.length - 1; i++) {
             String s = path[i];
             json = json.optJSONObject(s);
         }
         return json == null ? null : 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]);
 	}
 
 	@SuppressWarnings("unused")
     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
 		}
 
 		// deleted user? BUG in REST API: JRA-30263
 		final URI selfUri = optSelfUri(json, BasicUser.INCOMPLETE_URI);
 		return new BasicUser(selfUri, 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 JIRA_DATE_TIME_FORMATTER.parseDateTime(str);
 		} catch (Exception e) {
 			throw new RestClientException(e);
 		}
 	}
 
 	/**
 	 * Tries to parse date and time and return that. If fails then tries to parse date only.
 	 * @param str String contains either date and time or date only
 	 * @return date and time or date only
 	 */
 	public static DateTime parseDateTimeOrDate(String str) {
 		try {
 			return JIRA_DATE_TIME_FORMATTER.parseDateTime(str);
 		} catch (Exception ignored) {
 			try {
 				return JIRA_DATE_FORMATTER.parseDateTime(str);
 			} catch (Exception e) {
 				throw new RestClientException(e);
 			}
 		}
 	}
 
 	public static DateTime parseDate(String str) {
 		try {
 			return JIRA_DATE_FORMATTER.parseDateTime(str);
 		} catch (Exception e) {
 			throw new RestClientException(e);
 		}
 	}
 
 	public static String formatDate(DateTime dateTime) {
 		return JIRA_DATE_FORMATTER.print(dateTime);
 	}
 
 	@SuppressWarnings("unused")
 	public static String formatDateTime(DateTime dateTime) {
 		return JIRA_DATE_TIME_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();
     }
 
 	@SuppressWarnings("unused")
 	@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;
 	}
 
 	@Nullable
 	public static Long getOptionalLong(JSONObject jsonObject, String attributeName) throws JSONException {
 		return jsonObject.has(attributeName) ? jsonObject.getLong(attributeName) : null;
 	}
 
 	public static Optional<JSONArray> getOptionalArray(JSONObject jsonObject, String attributeName) throws JSONException {
 		return jsonObject.has(attributeName) ?
 				Optional.of(jsonObject.getJSONArray(attributeName)) : Optional.<JSONArray>absent();
 	}
 	
 	public static Map<String, URI> getAvatarUris(JSONObject jsonObject) throws JSONException {
 		Map<String, URI> uris = Maps.newHashMap();
 		
 		final Iterator iterator = jsonObject.keys();
 		while (iterator.hasNext()) {
 			final Object o = iterator.next();
 			if (!(o instanceof String)) {
 				throw new JSONException("Cannot parse URIs: key is expected to be valid String. Got " + (o == null ? "null" : o.getClass()) + " instead.");
 			}
 			final String key = (String) o;
 			uris.put(key, JsonParseUtil.parseURI(jsonObject.getString(key)));
 		}
 		return uris;
 	}
 
 	@SuppressWarnings("unchecked")
 	public static Iterator<String> getStringKeys(JSONObject json) {
 		return json.keys();
 	}
 }