package de.vanitasvitae.imi.codes;

import java.util.regex.Pattern;

public class InputValidator {

    // Allowed characters
    private static final String ALPHABET = "[a-zA-Z0-9]";

    /*
    REGEX pattern for study numbers. Allowed are all 3-letter numbers from the alphabet [a-zA-Z0-9].
     */
    private static final Pattern STUDY_NUMBER_MATCHER = Pattern.compile(ALPHABET+"{3}");

    /*
    REGEX pattern for sample numbers. Allowed are four-letter numbers from the alphabet [a-zA-Z0-9].
     */
    private static final Pattern SAMPLE_NUMBER_MATCHER = Pattern.compile(ALPHABET+"{4}");

    /**
     * Validate a given study number. Valid study numbers are 3-letter codes from the alphabet [a-zA-Z0-9].
     *
     * @param in input String
     * @return unmodified input String if it matches.
     * @throws IllegalArgumentException if the input String doesn't match the regex.
     */
    public static String validateStudyNumber(String in) {
        if (!STUDY_NUMBER_MATCHER.matcher(in).matches()) {
            throw new IllegalArgumentException("Study number does not match REGEX.");
        }

        return in;
    }

    /**
     * Validate a given sample type. Valid types are found in {@link SampleType}.#
     *
     * @param in input String
     * @return parsed {@link SampleType}.
     *
     * @throws IllegalArgumentException if the given String doesn't match a {@link SampleType}.
     * @throws NullPointerException in case the given String is {@code null}.
     */
    public static SampleType validateSampleType(String in) {
        return SampleType.valueOf(in);
    }
}