import java.util.ArrayList; 
/**
 * Created by leon on 1/29/18.
 */
public class StringArrayUtils {
    /**
     * @param array array of String objects
     * @return first element of specified array
     */ // TODO
    public static String getFirstElement(String[] array) {
        return array[0];
    }

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

    /**
     * @param array array of String objects
     * @return last element in specified array
     */ // TODO
    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
     */ // TODO
    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`
     */ // TODO
    public static boolean contains(String[] array, String value) {
        boolean match = false;
        for(int i = 1; i < array.length; i++){
            if(array[i] == value){
                match = true;
                break;
            } else {

                match = false;
            }
        }
        return match;
    }

    /**
     * @param array of String objectsjava object api
     * 
     * @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;
            }else {
                palindrome = false;
            }

        }
        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 pan = false;
        StringBuilder build = new StringBuilder();
        for (String s: array){
            build.append(s);
        }
            String ofArr = "";
            ofArr = build.toString();
        
        for(char i = 'A'; i <='Z'; i++){
            if((ofArr.indexOf(i) < 0) && (ofArr.indexOf((char)(i+32))<0)){
                pan = false;
            }else{
                pan = true;
            }

        }

        return pan;
    }

    /**
     * @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 occurrances = 0;
         
         for(String i : array) {
            if(value == i){
            occurrances++;
               }
            }
         
         return occurrances;
    }

    /**
     * @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;
}
}