package com.roboclub.robobuggy.nodes.sensors;

import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.roboclub.robobuggy.main.RobobuggyConfigFile;
import com.roboclub.robobuggy.main.RobobuggyLogicNotification;
import com.roboclub.robobuggy.main.RobobuggyMessageLevel;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Map;
import java.util.Scanner;

/**
 * @author Trevor Decker
 *         An object for reading the header configuration file so that low level and high level are synchronized on the RBSM communication protocol
 */
public class RBSMConfigReader {
    private JsonObject headers;
    private static RBSMConfigReader instance;

    /**
     * evaluates to a reference of the only RBSMConfigReader on the system
     * allows for any object to access header information
     *
     * @return RBSMConfigReader reference
     */
    public static synchronized RBSMConfigReader getInstance() {
        if (instance == null) {
            instance = new RBSMConfigReader();
        }
        return instance;
    }

    /**
     * gets the headers json object
     *
     * @return the json object to lookup header values
     */
    public JsonObject getHeaders() {
        return headers;
    }

    /**
     * The constructor for the RBSMConfig reader, this file function is where the RBSM header file is read and its data is stored
     */
    public RBSMConfigReader() {
        headers = new JsonObject();
        try {
            Scanner fileIn = new Scanner(new File(RobobuggyConfigFile.RBSM_HEADER_FILE_LOCATION), "UTF-8");
            while (fileIn.hasNextLine()) {
                String line = fileIn.nextLine();
                if (!line.equals("") && !line.contains("//")) {
                    String[] lineContents = line.split(", ");
                    String headerName = lineContents[0];
                    int headerNumber = Integer.parseInt(lineContents[1]);

                    headers.addProperty(headerName, headerNumber);
                }
            }
        } catch (FileNotFoundException e) {
            new RobobuggyLogicNotification("rbsm header File not read correctly: " + e.getMessage(), RobobuggyMessageLevel.EXCEPTION);
        }
    }

    /**
     * Determines if the headerByte is a valid RBSM header
     *
     * @param headerByte header byte
     * @return true iff the headerByte is valid
     */
    public boolean isValidHeader(byte headerByte) {

        //see if that's a value in the headers object
        for (Map.Entry<String, JsonElement> object : headers.entrySet()) {
            if (object.getValue().getAsByte() == headerByte) {
                return true;
            }
        }

        return false;
    }

}