package Manager;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import Utility.User.UserPermission;
import Utility.chat.Chat;
import Utility.chat.ChatCategory;
import Utility.jsonUtils;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class ChatManager {

    private static Logger log = LoggerFactory.getLogger(ChatManager.class);

    private static final String CHATS_FILENAME = "chats.json";

    /**
     * Load All chats to look ak
     * @return list of Chats
     */
    public static Set<Long> loadWatch(){
        log.debug("Load WhatchChats");

        Set<Long> ret = new HashSet<>();
        for (Object o : jsonUtils.loadJson("WatchChats.json")){
            JSONObject x = (JSONObject) o;

            ret.add(Long.parseLong(x.get("ID").toString()));
        }
        return ret;
    }

    /**
     * Safe list of chats to look at
     * @param list list of chats to save
     */
    public static void saveWatch(Set<Long> list){
        log.debug("Save WhatchChats");

        JSONArray save = new JSONArray();

        for (long x : list){
            JSONObject tmp = new JSONObject();
            tmp.put("ID", Long.toString(x));
            save.add(tmp);
        }

        jsonUtils.saveJson(save, "WatchChats.json");
    }

    /**
     * Add a new Chat Category
     * @param category new Category
     */
    public static void addCategory(ChatCategory category) {
        log.info("Adding Utility.chat category " + category.getName());

        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);

        //Check if the uid is actually unique
        if (checkCategoryUID(category.getUid())) {
            log.debug("no unique Chat ID");
            return;
        }

        JSONObject newCategory = new JSONObject();
        newCategory.put("uid", category.getUid());
        newCategory.put("name", category.getName());
        newCategory.put("chats", new JSONArray());

        categories.add(newCategory);

        jsonUtils.saveJson(categories, CHATS_FILENAME);
    }

    /**
     * Load a List with all Chat Categories
     * @return List of ChatCategories
     */
    public static List<ChatCategory> loadCategories() {
        log.debug("Loading chat categories from file");

        JSONArray categoriesJson = jsonUtils.loadJson(CHATS_FILENAME);
        List<ChatCategory> categories = new ArrayList<>();

        for (Object o : categoriesJson) {
            JSONObject category = (JSONObject) o;
            long uid = (long) category.get("uid");

            categories.add(loadCategory(uid));
        }

        return categories;
    }

    /**
     * Load singe Chat Category by ID
     * @param uid id of Categoriy
     * @return ChatCategory
     */
    public static ChatCategory loadCategory(long uid) {
        log.debug("Loading chat category by uid " + uid);
        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);

        for (Object o : categories) {
            JSONObject category = (JSONObject) o;
            long searchUid = (long) category.get("uid");

            if (searchUid == uid) {
                String name = (String) category.get("name");
                JSONArray chatsJson = (JSONArray) category.get("chats");
                List<Chat> chats = new ArrayList<>();

                for (Object c : chatsJson) {
                    JSONObject chatJson = (JSONObject) c;
                    long chatUid = (long) chatJson.get("uid");
                    String chatName = (String) chatJson.get("name");
                    String chatUrl = (String) chatJson.get("url");
                    String permissionJson = (String) chatJson.get("permissionNeeded");
                    UserPermission permissionNeeded = UserPermission.valueOf(permissionJson);

                    chats.add(new Chat(chatUid, chatName, chatUrl, permissionNeeded));
                }

                ChatCategory found = new ChatCategory(uid, name);
                found.setChatList(chats);

                return found;
            }
        }
        return null;
    }

    /**
     * Delete existing Category
     * @param uid id of Category to delete
     */
    public static void deleteCategory(long uid) {
        log.info("delete Category: " + uid);

        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);

        for (Object o : categories) {
            JSONObject category = (JSONObject)o;
            long searchUid = (Long) category.get("uid");

            if (searchUid == uid) {
                categories.remove(o);
                break;
            }
        }

        jsonUtils.saveJson(categories, CHATS_FILENAME);
    }

    /**
     * Check if a ChatCategory uid already exists
     * @param uid ID to check
     * @return boolean true if exists
     */
    public static boolean checkCategoryUID(long uid) {
        log.debug("Checking if Utility.chat category " + uid + " already exists");
        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);

        for (Object o : categories) {
            JSONObject category = (JSONObject) o;
            long searchUid = (long) category.get("uid");

            if (uid == searchUid) {
                return true;
            }
        }
        return false;
    }

    /**
     * Check if a Chat uid already exists
     * @param uid ID to check
     * @return boolean true if exists
     */
    public static boolean checkChatUID(long uid) {
        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);

        for (Object o : categories) {
            JSONObject category = (JSONObject)o;
            JSONArray chats = (JSONArray)category.get("chats");

            for (Object c : chats) {
                JSONObject chat = (JSONObject) c;
                long chatUid = (long) chat.get("uid");

                if (uid == chatUid)
                    return true;
            }
        }
        return false;
    }

    /**
     * Get biggest chatCategory Uid
     * @return Greatest UID
     */
    public static long getBiggestChatCategoryUid() {
        log.debug("Get biggest Utility.chat category uid");
        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);
        long biggestUid = 0;

        for (Object o : categories) {
            JSONObject category = (JSONObject) o;
            long uid = (long) category.get("uid");
            if (uid > biggestUid) {
                biggestUid = uid;
            }
        }

        return biggestUid;
    }

    /**
     * Save Chat into Category
     * @param chat Chat to save
     * @param categoryUid Category to save chat into
     */
    public static void saveChat(Chat chat, long categoryUid)
    {
        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);

        //search for Category
        for (Object o : categories) {
            JSONObject category = (JSONObject)o;
            long searchCategoryUid = (Long) category.get("uid");

            //If found
            if (searchCategoryUid == categoryUid) {

                JSONArray chats = (JSONArray)category.get("chats");

                //search if chat already exist
                for (Object c : chats) {
                    JSONObject searchChat = (JSONObject)c;
                    long searchChatUid = (Long) searchChat.get("uid");

                    //if chat already exists, delete it
                    if (searchChatUid == chat.getUid()) {
                        chats.remove(c);
                        break;
                    }
                }

                //save chat
                JSONObject chatJson = new JSONObject();
                chatJson.put("uid", chat.getUid());
                chatJson.put("name", chat.getName());
                chatJson.put("url", chat.getUrl());
                chatJson.put("permissionNeeded", chat.getPermissionNeeded().toString());
                chats.add(chatJson);
            }
        }
        jsonUtils.saveJson(categories, CHATS_FILENAME);
    }

    /**
     * Loads specific chat out of specific category
     * @param chatUid chat id to load
     * @param categoryUid category id where chat is located
     * @return Chat
     */
    public static Chat loadChatFromCategory(long chatUid, long categoryUid)
    {
        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);

        for (Object o : categories) {
            JSONObject category = (JSONObject)o;
            long searchCategoryUid = (Long) category.get("uid");

            if (searchCategoryUid == categoryUid) {
                JSONArray chats = (JSONArray)category.get("chats");

                for (Object c : chats) {
                    JSONObject chat = (JSONObject)c;
                    long searchChatUid = (Long) chat.get("uid");

                    if (searchChatUid == chatUid) {
                        String name = (String)chat.get("name");
                        String url = (String)chat.get("url");
                        String permissionString = (String)chat.get("permissionNeeded");
                        UserPermission permissionNeeded = UserPermission.valueOf(permissionString);

                        return new Chat(chatUid, name, url, permissionNeeded);
                    }
                }
            }
        }
        return null;
    }

    /**
     * Delete Chat
     * @param chatUid ID of chat to delete
     */
    public static void deleteChat(long chatUid)
    {
        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);

        for (Object o : categories) {
            JSONObject category = (JSONObject)o;
            JSONArray chats = (JSONArray)category.get("chats");

            for (Object c : chats) {
                JSONObject searchChat = (JSONObject)c;
                long searchChatUid = (Long) searchChat.get("uid");

                if (searchChatUid == chatUid) {
                        chats.remove(c);
                    break;
                }
            }
            category.put("chats", chats);
        }
        jsonUtils.saveJson(categories, CHATS_FILENAME);
    }

    /**
     * Change UID of a Chat
     * @param chat new Chat
     * @param categoryUid Category ID where chat is located
     * @param oldUid ID of Chat to change
     */
    public static void changeUid(Chat chat, long categoryUid, long oldUid)
    {
        JSONArray categories = jsonUtils.loadJson(CHATS_FILENAME);

        for (Object o : categories) {

            JSONObject category = (JSONObject)o;

            long searchCategoryUid = (Long) category.get("uid");

            if (searchCategoryUid == categoryUid) {
                JSONArray chats = (JSONArray)category.get("chats");

                for (Object c : chats) {

                    JSONObject searchChat = (JSONObject)c;
                    long searchChatUid = (Long) searchChat.get("uid");

                    if (searchChatUid == oldUid) {
                        searchChat.put("uid", chat.getUid());
                        searchChat.put("name", chat.getName());
                        searchChat.put("url", chat.getUrl());
                        searchChat.put("permissionNeeded", chat.getPermissionNeeded().toString());
                    }
                }
            }
        }
        jsonUtils.saveJson(categories, CHATS_FILENAME);
    }
}