/*-
 * ============LICENSE_START=======================================================
 * ONAP : APPC
 * ================================================================================
 * Copyright (C) 2017-2018 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * Copyright (C) 2017 Amdocs
 * =============================================================================
 * 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.
 * 
 * ============LICENSE_END=========================================================
 */

package org.onap.sdnc.config.generator.tool;

import com.att.eelf.configuration.EELFLogger;
import com.att.eelf.configuration.EELFManager;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.codehaus.jettison.json.JSONArray;
import org.codehaus.jettison.json.JSONException;
import org.codehaus.jettison.json.JSONObject;


public class JSONTool {

    private static final EELFLogger log = EELFManager.getInstance().getLogger(JSONTool.class);

    private JSONTool() {
    }

    public static Map<String, String> convertToProperties(String s) throws JSONException {
        return convertToProperties(s, null);
    }

    public static Map<String, String> convertToProperties(String s, List<String> blockKeys)
        throws JSONException {
        JSONObject json = new JSONObject(s);
        Map<String, String> mm = new HashMap<>();
        Map<String, Object> wm = new HashMap<>();

        Iterator<String> ii = json.keys();
        while (ii.hasNext()) {
            String key1 = ii.next();
            wm.put(key1, json.get(key1));
        }
        while (!wm.isEmpty()) {
            for (String key : new ArrayList<>(wm.keySet())) {
                Object o = wm.get(key);
                wm.remove(key);
                tryAddBlockKeys(blockKeys, mm, key, o);
                if (o instanceof Boolean || o instanceof Number || o instanceof String) {
                    String oString = o.toString();
                    //Add escape characters to the string in case it is a string representation
                    //of a json object.
                    oString = JSONObject.quote(oString, false);
                    //Remove the surrouding quotes added by the JSONObject.quote() method.
                    //JSONObject.quote() will always return, at minimum, a string with two quotes,
                    //even if a null string is passed to it. So this substring method does not
                    //need any checks.
                    oString = oString.substring(1, oString.length() - 1);
                    mm.put(key, oString);
                    log.info("Added property: " + key + ": " + oString);
                } else if (o instanceof JSONObject) {
                    fill(wm, key, (JSONObject) o);
                } else if (o instanceof JSONArray) {
                    fill(mm, wm, key, (JSONArray) o);
                }
            }
        }
        return mm;
    }

    //Finds json values which themselves contain String representations of json
    //data and adds escape characters to the quotes. Example:
    //Input: { "key1": "{"internalKey1": "internalValue1"}" }
    //Output: { "key1": "{\"internalKey1\": \"internalValue1\"}" }
    public static String escapeInternalJson(String jsonString) throws JSONException
    {
        StringBuilder sb = new StringBuilder();
        char lastChar = 0;
        boolean inJson = false;
        for(char c : jsonString.toCharArray()) {
            //If we see a { directly after a quote, it would mean that this string will contain json data
            //as a string.
            if(c == '{' && lastChar == '"') {
                inJson = true;
            }
            //Checks if we are currently in a json block and if the character we are looking at is
            //a quote. The quote is what needs to be escaped.
            if(inJson && c == '"') {
                //If a } precedes a quote, then this would signal the end of a string containing json
                if(lastChar == '}') {
                    inJson = false;
                    //since this quote we are looking at is outside the json string block, we should not escape it
                    sb.append("\"");
                } else {
                    //Else block for the case where the quote was preceded by anything other than a }
                    //We know we are still in the json string block
                    //If the last character was not a backslash, we know that the quote we are looking at has
                    //not been escaped.
                    if(lastChar != '\\') {
                        //un-escaped quote should be escaped
                        sb.append("\\\"");
                    } else {
                        //quote is already escaped, we can add it as it is
                        sb.append(c);
                    }
                }
            } else {
                //If we are not in a json block, or if the character is not a quote, it can be added as is
                sb.append(c);
            }
            if(!Character.isWhitespace(c)) {
                lastChar = c;
            }
        }
        if(inJson == true) {
            //We reached the end of the string, but the internal string containing
            //the json data to escape never ended.
            throw new JSONException("End of json data reached, but end of internal"
                    + "json string never reached.");
        }
        return sb.toString();
    }

    private static void tryAddBlockKeys(List<String> blockKeys, Map<String, String> mm, String key, Object o) {
        if (blockKeys != null && blockKeys.contains(key) && o != null) {
            mm.put("block_" + key, o.toString());
            log.info("Adding JSON Block Keys : " + key + "=" + o.toString());
        }
    }

    private static void fill(Map<String, String> mm, Map<String, Object> wm, String key, JSONArray array)
        throws JSONException {
        mm.put("size_" + key, String.valueOf(array.length()));
        log.info("Added property: " + key + "_length" + ": " + array.length());

        for (int i = 0; i < array.length(); i++) {
            wm.put(key + '[' + i + ']', array.get(i));
        }
    }

    private static void fill(Map<String, Object> wm, String key, JSONObject object) throws JSONException {

        Iterator<String> i = object.keys();
        while (i.hasNext()) {
            String key1 = i.next();
            wm.put(key + "." + key1, object.get(key1));
        }
    }
}