package com.ufund.api.ufundapi.persistence;

import java.io.File;
import java.io.IOException;
import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.Map;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.ufund.api.ufundapi.model.UserAuth;

@Component
public class UserAuthFIleDAO implements UserAuthDAO {

    private final Map<String, UserAuth> userAuthMap;
    private final ObjectMapper objectMapper;
    private final String filename;

    public UserAuthFIleDAO(ObjectMapper objectMapper, @Value("${authKeys.file}") String filename) throws IOException {
        this.userAuthMap = new HashMap<>();
        this.objectMapper = objectMapper;
        this.filename = filename;
        load();
    }

    /**
     * Loads the data from the file into the map
     *
     * @throws IOException Thrown if there was an issue reading the file
     */
    private void load() throws IOException {
        userAuthMap.clear();

        UserAuth[] userAuthKeysArray = objectMapper.readValue(new File(filename), UserAuth[].class);

        for (UserAuth userAuth : userAuthKeysArray) {
            if (userAuth.getExpiration().isAfter(LocalDateTime.now())) {
                userAuthMap.put(userAuth.getKey(), userAuth);
            }
        }
    }

    /**
     * Saves the data from the map into the json file
     *
     * @throws IOException Thrown on any problem writing the file
     */
    private void save() throws IOException {
        objectMapper.writeValue(new File(filename), userAuthMap.values());
    }

    @Override
    public UserAuth getUserAuth(String key) {
        synchronized (userAuthMap) {
            return userAuthMap.get(key);
        }
    }

    @Override
    public void addUserAuth(UserAuth userAuth) throws IOException {
        synchronized (userAuthMap) {
            userAuthMap.put(userAuth.getKey(), userAuth);
            save();
        }
    }

    @Override
    public void removeUserAuth(String key) throws IOException {
        synchronized (userAuthMap) {
            userAuthMap.remove(key);
            save();
        }
    }
}