package be.mentoringsystems.merke.helper;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;
import javax.annotation.Nullable;
import org.apache.commons.lang3.math.NumberUtils;

/**
 *
 * @author anthonyarents
 */
public final class ConversionHelper {

    private static final DateTimeFormatter LOCALDATEFORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd");
    private static final DateTimeFormatter LOCALDATETIMEFORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");

    private ConversionHelper() {
    }

    @SuppressWarnings("unchecked")
    public static List<Object> toObjectList(final Object obj) {
        List<Object> result = new ArrayList<Object>();
        if (obj == null) {
            return result;
        }
        if (obj instanceof List) {
            return (List<Object>) obj;
        } // assume it's always a list of string, this is done by spring automatically ...
        result.add(obj);
        return result;
    }

    @SuppressWarnings("unchecked")
    public static List<String> toStringList(final Object obj) {
        List<String> result = new ArrayList<String>();
        if (obj == null) {
            return result;
        }
        if (obj instanceof List) {
            return (List<String>) obj;
        } // assume it's always a list of string, this is done by spring automatically ...
        if (obj instanceof String) {
            result.add((String) obj);
        }
        return result;
    }

    @SuppressWarnings("unchecked")
    public static List<Integer> toIntegerList(final Object obj) {
        List<Integer> result = new ArrayList<Integer>();
        if (obj == null) {
            return result;
        }
        if (obj instanceof List) {
            return (List<Integer>) obj;
        } // assume it's always a list of integer, this is done by spring automatically ...
        if (obj instanceof Integer) {
            result.add((Integer) obj);
        }
        return result;
    }

    public static List<UUID> toUUIDList(final Object obj) {
        List<UUID> result = new ArrayList<UUID>();
        if (obj == null) {
            return result;
        }
        List<Object> start = toObjectList(obj);
        for (Object o : start) {
            UUID u = toUUID(o);
            if (u != null) {
                result.add(u);
            }
        }
        return result;
    }

    public static UUID toUUID(final Object obj) {
        if (obj == null) {
            return null;
        }
        if (obj instanceof UUID) {
            return (UUID) obj;
        }
        return UUID.fromString(toString(obj));
    }

    public static String toString(final Object obj) {
        if (obj == null) {
            return null;
        }
        if (obj instanceof String) {
            return (String) obj;
        }
        return obj.toString();
    }

    public static LocalDate toLocalDate(final Object obj) {
        if (obj == null) {
            return null;
        }
        if (obj instanceof LocalDate) {
            return (LocalDate) obj;
        }
        String dateString = toString(obj);
        if (dateString == null) {
            return null;
        } else {
            return (LocalDate) LOCALDATEFORMATTER.parse(dateString);
        }
    }

    public static LocalDateTime toLocalDateTime(final Object obj) {
        if (obj == null) {
            return null;
        }
        if (obj instanceof LocalDateTime) {
            return (LocalDateTime) obj;
        }
        String dateString = toString(obj);
        if (dateString == null) {
            return null;
        } else {
            return (LocalDateTime) LOCALDATETIMEFORMATTER.parse(dateString);
        }
    }

    public static Integer toInteger(final Object obj) {
        if (obj == null) {
            return null;
        }
        if (obj instanceof Integer) {
            return (Integer) obj;
        }
        return NumberUtils.toInt(toString(obj));
    }

    @Nullable
    public static Boolean toBoolean(final Object obj) {
        if (obj == null) {
            return null;
        }
        if (obj instanceof Boolean) {
            return (Boolean) obj;
        }
        String objString = toString(obj);
        if ("1".equals(objString) || "true".equals(objString)) {
            return Boolean.TRUE;
        }
        return Boolean.FALSE;
    }
}