import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.*;
import java.lang.StringBuilder;
import java.lang.String;
/**
 * Created by leon on 1/29/18.
 */
public class StringArrayUtils {
    /**
     * @param array array of String objects
     * @return first element of specified array
     */ // DONE
    public static String getFirstElement(String[] array) {

        return array[0];
    }

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

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

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

    /**
     * @param array array of String objects
     * @param value value to check array for
     * @return true if the array contains the specified `value`
     */ // DONE
    public static boolean contains(String[] array, String value) {
        boolean check = false;

        for (int i = 0; i<array.length; i++){
            if (array[i] == value){
                check = true;}
        }
        return check;
    }

    /**
     * @param array of String objects
     * @return an array with identical contents in reverse order
     */ // DONE
    public static String[] reverse(String[] array) {

        for (int i = 0; i<array.length/2; i++){
            String 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
     */ // DONE
    public static boolean isPalindromic(String[] array) {
        boolean check = false;
        for (int i=0; i<array.length/2; i++){
            String temp = array[i];
            array[i] = array[array.length-1-i];
            array[array.length-1-i] = temp;

            if ( temp == array[i]){
                check = true;
            }
        }
        return check;
    }

    /**
     * @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) {

        String alphabet = "abcdefghijklmnopqrstuvwxyz";
        boolean pan = true;
        boolean check = false;
            
        for (int i = 0; i>26; i++){
            
            for(String string:array){
                
                if (string.contains(Character.toString(alphabet.charAt(i)))){    
                    check = true;
                }
                
                else{ check = false;
                }
            }
            if (check == false){
                pan = false;
                break;
            }
        }
        return pan;
    }
        /**
         * @param array array of String objects
         * @param value value to check array for
         * @return number of occurrences the specified `value` has occurred
         */ // Done
        public static int getNumberOfOccurrences(String[] array, String value) {
        int counter = 0;
        for (int i = 0; i<array.length; i++){
            if (array[i] == value){
                counter=counter+1;   
            }

        }

        return counter;
    }

    /**
     * @param array         array of String objects
     * @param valueToRemove value to remove from array
     * @return array with identical contents excluding values of `value`
     */ // Done
    public static String[] removeValue(String[] array, String valueToRemove) {

        String [] temp = new String[array.length-(getNumberOfOccurrences(array,valueToRemove))];

        for(int i = 0 ,j = 0;  i<array.length; i++){
            if(!array[i].equals(valueToRemove)){

                temp[j] = array[i];
                j++;
            }
        }

        return temp;
    }

    public static int duplicates(String[] array){
        String dupes = new String();
        int counter = 0;
        for (int i=0; i<array.length-1;i++){
            if (array[i] == array[i+1]){
                counter++;
                //dupes += (array[i]);
            }
        }
        return counter;
    }

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

    /**
     * @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) {
        String[] pack = new String[array.length-duplicates(array)];
        int j = 0;
        pack[0]=array[0];
        for(int i=1; i<array.length; i++){

            if (array[i] == array[i-1]){
                pack[j] += array[i];
            }
            else{
                j++;
                pack[j]=array[i];
            }
        }

        return pack;
    }

}