package com.company;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Author 6543
 * Datum 2019-10-14
 * License GPL3
 */

public enum Version {
    UNKNOWN,
    SUPPORTED_LATEST,
    SUPPORTED_OLD,
    DEVELOPMENT,
    UNSUPPORTED_OLD,
    UNSUPPORTED_NEW;



    public static Version check(String min, String last, String value) {

        final Pattern pattern_stable_release = Pattern.compile("^(\\d)\\.(\\d+)\\.(\\d+)$");
        final Pattern pattern_dev_release = Pattern.compile("^(\\d).(\\d+).(\\d+)(\\D)(.+)");
        Matcher m ;

        if (!pattern_stable_release.matcher(min).find() || !pattern_stable_release.matcher(last).find()) {
            throw new Error("VersionCheck: wrong format for min or last version given");
        }

        m = pattern_stable_release.matcher(value);
        if (m.find()) {

            switch (correlate(min, last, m.group())){
                case 0:
                    return UNSUPPORTED_OLD;
                case 1:
                    return SUPPORTED_OLD;
                case 2:
                    return SUPPORTED_LATEST;
                default:
                    return UNSUPPORTED_NEW;
            }

        }
        m = pattern_dev_release.matcher(value);
        if (m.find()) {

            m = Pattern.compile("^(\\d)\\.(\\d+)\\.(\\d+)").matcher(value);
            m.find();

            if (correlate(min, last, m.group())>0) {
                return DEVELOPMENT;
            } else {
                return UNSUPPORTED_OLD;
            }

        }

        return UNKNOWN;

    }

    //helper
    // 0 to less
    // 1 in range
    // 2 at the top
    // 3 above
    private static int correlate(String min, String last, String value){
        //init
        int i_min = 0, i_last = 0, i_value = 0;

        //go down each integer (separated by points) until it is the last one
        while (value.contains(".")) {

            //prepare for checks
            i_min = Integer.parseInt(min.substring(0,min.indexOf(".")));
            i_last = Integer.parseInt(last.substring(0,last.indexOf(".")));
            i_value = Integer.parseInt(value.substring(0,value.indexOf(".")));

            if (i_value < i_min) return 0;
            if (i_value > i_last) return 3;

            //check in range correlation
            int result = correlate(min.substring(min.indexOf(".")+1),last.substring(last.indexOf(".")+1),value.substring(value.indexOf(".")+1));

            if (i_value == i_last) {
                switch (result){
                    case 0:
                        return 0;
                    case 1:
                        return 1;
                    case 2:
                        if (i_value < i_last ) return 1;
                        if (i_value == i_last) return 2;
                    case 3:
                        return 3;
                }
            } else { //value in range
                return 1;
            }
        }

        i_min = Integer.parseInt(min);
        i_last = Integer.parseInt(last);
        i_value = Integer.parseInt(value);

        //check last integer
        if (i_min > i_last){
            if (i_value == i_last) return 2;
            if (i_value < i_last) return 1;
        }
        if (i_value < i_min) return 0;
        if (i_value >= i_min && i_value < i_last) return 1;
        if (i_value == i_last) return 2;
        return 3;
    }


        return 0;
    }
}