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package pl.jalokim.utils.string;

import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.function.Function;
import java.util.stream.Collectors;

import static java.util.Collections.nCopies;
import static pl.jalokim.utils.constants.Constants.EMPTY;
import static pl.jalokim.utils.constants.Constants.NEW_LINE;
import static pl.jalokim.utils.constants.Constants.TAB;

public final class StringUtils {

    private StringUtils() {

    }
    /**
     * Check that text is empty or null.
     * @param text to check.
     * @return boolean value
     */
    public static boolean isEmpty(String text) {
        return text == null || text.isEmpty();
    }

    /**
     * Check that text is not empty.
     * @param text to check.
     * @return boolean value
     */
    public static boolean isNotEmpty(String text) {
        return !isEmpty(text);
    }

    /**
     * If whole text contains only white signs then return true
     * @param text to check.
     * @return boolean value
     */
    public static boolean isBlank(String text) {
        return text == null || isBlank(text.toCharArray());
    }

    /**
     * If whole text doesn't contain only white signs then return true
     * @param text to check.
     * @return boolean value
     */
    public static boolean isNotBlank(String text) {
        return !isBlank(text);
    }

    private static boolean isBlank(char... chars) {
        boolean result = true;
        for(char aChar : chars) {
            result = result && Character.isWhitespace(aChar);
            if(!result) {
                break;
            }
        }
        return result;
    }

    /**
     * Return concatenated text all list elements as new lines.
     * @param elements to concatenate
     * @return concatenated text.
     */
    public static  String concatElementsAsLines(List elements) {
        return concatElements(elements,
                              NEW_LINE);
    }

    /**
     * Return concatenated text all list elements as new lines.
     * @param elements to concatenate
     * @param mapper for from E type to string
     * @param  generic type for
     * @return concatenated text.
     */
    public static  String concatElementsAsLines(List elements, Function mapper) {
        return concatElements(elements,
                              mapper,
                              NEW_LINE);
    }

    /**
     * It return N times of tabulator
     * @param tabsNumber number of Tabs
     * @return created n times tabs.
     */
    public static String tabsNTimes(int tabsNumber) {
        return repeatTextNTimes(tabsNumber, TAB);
    }

    /**
     * It create text with n times repeated text
     * @param nTimes number to repeat
     * @param text value to repeat
     * @return created n times text.
     */
    public static String repeatTextNTimes(int nTimes, String text) {
        return String.join(EMPTY, nCopies(nTimes, text));
    }

    /**
     * Concatenate elements with empty text. On every object will be called toString().
     * @param collection elements to concatenate
     * @param  generic type of collection.
     * @return concatenated text.
     */
    public static  String concatElements(Collection collection) {
        return concatElements(collection, EMPTY);
    }

    /**
     * Concatenate elements with empty text with mapper from E type to String.
     * @param collection elements to concatenate
     * @param mapper from some type to String
     * @param  generic type of collection.
     * @return concatenated text.
     */
    public static  String concatElements(Collection collection, Function mapper) {
        return concatElements(collection, mapper, EMPTY);
    }

    /**
     * Concatenate elements with joinText value.
     * @param collection elements to concatenate
     * @param joinText value between all texts.
     * @param  generic type of collection.
     * @return concatenated text.
     */
    public static  String concatElements(Collection collection, String joinText) {
        return concatElements(collection, Object::toString, joinText);
    }

    /**
     * Concatenate elements with joinText value with mapper from E type to String
     * @param collection elements to concatenate
     * @param mapper from some type to String
     * @param joinText value between all texts.
     * @param  generic type of collection.
     * @return concatenated text.
     */
    public static  String concatElements(Collection collection, Function mapper, String joinText) {
        return concatElements(EMPTY, collection, mapper, joinText, EMPTY);
    }

    /**
     * Concatenate elements with prefix, join text between all elements and with suffix value with mapper from E type to String
     * @param textPrefix text before all concatenated text
     * @param collection elements to concatenate
     * @param mapper from some type to String
     * @param joinText value between all texts.
     * @param textSuffix text after all concatenated text
     * @param  generic type of collection.
     * @return concatenated text with empty text.
     */
    public static  String concatElements(String textPrefix, Collection collection, Function mapper,
                                                 String joinText, String textSuffix) {
        return textPrefix.concat(collection.stream()
                                           .map(mapper)
                                           .collect(Collectors.joining(joinText))
                                ).concat(textSuffix);
    }

    /**
     * This method concatenate all texts from array with join Text
     * @param joinText between all varargs.
     * @param texts varargs for text.
     * @return concatenated text
     */
    public static String concatElements(String joinText, String... texts) {
        return concatElements(Arrays.asList(texts), joinText);
    }

    /**
     * concatenate all elements with empty string value.
     * @param texts to concatenate
     * @return concatenated text
     */
    public static String concat(String... texts) {
        return concatElements(Arrays.asList(texts), EMPTY);
    }
}