/**
 * Created by leon on 1/29/18.
 */

import java.util.Collections;

public class StringArrayUtils {
    /**
     * @param array array of String objects
     * @return first element of specified array
     */ // TODO
    public static String getFirstElement(String[] array) {
        String firstElement = array[0];
        
        return firstElement;
    }

    /**
     * @param array array of String objects
     * @return second element in specified array
     */
    public static String getSecondElement(String[] array) {
        String secondElement = array[1];
        
        return secondElement;
    }

    /**
     * @param array array of String objects
     * @return last element in specified array
     */ // TODO
    public static String getLastElement(String[] array) {
        String lastElement = array[array.length-1];
        
        return lastElement;
    }

    /**
     * @param array array of String objects
     * @return second to last element in specified array
     */ // TODO
    public static String getSecondToLastElement(String[] array) {
        String secondToLast = array[array.length-2];
        return secondToLast;
    }

    /**
     * @param array array of String objects
     * @param value value to check array for
     * @return true if the array contains the specified `value`
     */ // TODO
    public static boolean contains(String[] array, String value) {
        boolean contains = false;
        
        for (int i = 0; i < array.length; i++) {
            if (array[i].equalsIgnoreCase(value)) {
                contains = true;
        }
    }
        return contains;
    }

    /**
     * @param array of String objects
     * @return an array with identical contents in reverse order
     */ // TODO
    public static String[] reverse(String[] array) {
        
        String temp;
        for (int i = 0; i <= array.length/2; i++) {
            temp = array[i];
            array[i] = array[array.length -1 -i];
            array[array.length -1 -i] = temp;
            
        }
        return array;
    }

    /**
     * @param array array of String objects
     * @return true if the order of the array is the same backwards and forwards
     */ // TODO
    public static boolean isPalindromic(String[] array) {
        boolean palindrome = false;
        for (int i = 0; i <= array.length/2; i++) {
            if (array[i] == array[array.length -1 -i]) {
                palindrome = true;
        }
        
        
        }
        return palindrome;
    }

    /**
     * @param array array of String objects
     * @return true if each letter in the alphabet has been used in the array
     */ // TODO
    public static boolean isPangramic(String[] array) {
        boolean pangram = false;
        
        StringBuilder build = new StringBuilder();
        
        for (String s : array){
            build.append(s);
        }
        
        String ofArr = "";
        ofArr = build.toString();
            for (char a = 'A'; a <= 'Z'; a++) {
                if ((ofArr.indexOf(a) < 0) && (ofArr.indexOf((char)(a + 32)) < 0)) {
                    pangram = false;
            } else {
                    pangram = true;
                    
            }
        }
        return pangram;
    }

    /**
     * @param array array of String objects
     * @param value value to check array for
     * @return number of occurrences the specified `value` has occurred
     */ // TODO
    public static int getNumberOfOccurrences(String[] array, String value) {
        int count = 0;
        
        for (int i = 0; i < array.length; i++) {
            if (array[i] == value) {
                count++;
            }
        }
        
        
        return count;
    }

    /**
     * @param array         array of String objects
     * @param valueToRemove value to remove from array
     * @return array with identical contents excluding values of `value`
     */ // TODO
    public static String[] removeValue(String[] array, String valueToRemove) {
        int index = 0;
        int count = getNumberOfOccurrences(array, valueToRemove);
        String [] newArr = new String [array.length - count] ;
        
        for (int i = 0; i < array.length; i++) {
           if (array[i] != valueToRemove) {
               
               newArr[index] = array[i];
               index++;
            }
        }
        return newArr;
        
        
    }

    /**
     * @param array array of chars
     * @return array of Strings with consecutive duplicates removes
     */ // TODO
    public static String[] removeConsecutiveDuplicates(String[] array) {
        String last = null;
        int index = 0;
        int count = 0; 
        
        
        for (int i = 0; i < array.length - 1; i++) {
            if (array[i].equals(array[i + 1])) {
                count++;
            }
        }
        
        String [] newArr = new String [array.length - count];
        
        for (int i = 0; i < array.length; i++) {
            
            
            if (!array[i].equals(last)){
                newArr[index] = array[i];
                last = array[i];
                index++;
            }
        }
        
        return newArr;
    }

    /**
     * @param array array of chars
     * @return array of Strings with each consecutive duplicate occurrence concatenated as a single string in an array of Strings
     */ // TODO
    public static String[] packConsecutiveDuplicates(String[] array) {
        int getCounting = getCount(array);
        String [] savedArr = new String [array.length - getCounting];
        String last = array[0];
        savedArr[0] = array[0];
        int index = 0;
        
        for (int i = 1; i < array.length; i++) {
            if (array[i].equals(last)) {
                savedArr[index] += array[i];
            }
            else {
                index++;
                savedArr[index] = array[i];
                last = array[i];
        }
        
    }
        
        return savedArr;
    
    }

    private static int getCount (String[] array){
        int count = 0; 
        
        
        for (int i = 0; i < array.length - 1; i++) {
            if (array[i].equals(array[i + 1])) {
                count++;
            }
        }
        return count;
    }
}