package combinations;

import java.util.Vector;

public class Driver {
	
	int numberOfFields;
	
	int fieldLength;
	
	int bitsConstrained;
	
	int count;
	
	Vector<Integer> fieldLengthCollection;
	
	Vector<Integer> bitsConstrainedCollection;
	
	Vector<Integer> countCollection;
	
	public Driver(){
		
		numberOfFields = 5;
		
		fieldLength = -1;
		
		bitsConstrained = -1;
		
		count = -1;
		
		fieldLengthCollection = new Vector<Integer>();
		
		bitsConstrainedCollection = new Vector<Integer>();
		
		countCollection = new Vector<Integer>();
		
	}

	public Vector<String> getCombo_AllBitsConstrained( int fieldLength ){
		
		Vector<String> combos = new Vector<String>();
		
		String combo = "";
		
		for(int i=0; i<2; i++){
		
			for(int j=0; j<fieldLength; j++){
			
				if( i == 0 )
					combo += "0";
				else
					combo += "1";
			
			}
			
			combos.add( combo );
			combo = new String();
			
		}
		
		return combos;
		
	}
	
	public int getCount_AllBitsConstrained( int fieldLength ){
		
		Vector<String> combos = getCombo_AllBitsConstrained( fieldLength );
	
		return combos.size();
		
	}
	
	public int convertBinaryToInt( String binaryString ){
		
		double sum = 0.0d;
		
		int binaryStringLength = binaryString.length();
		
		int bitIndexStart = -1;
		int bitIndexEnd = -1;
		
		
		for(int i=0; i<binaryStringLength; i++){
			
			bitIndexEnd = binaryStringLength - i;
			bitIndexStart = binaryStringLength - (i+1);
			
			System.out.println( "binaryString.substring( start("+bitIndexStart+"), e("+bitIndexEnd+") ): " + binaryString.substring( i, i+1 ) );
			
			if( new Integer( binaryString.substring( bitIndexStart, bitIndexEnd ) ).intValue() > 0 )
				sum += Math.pow( 2.0, (double)i );
			
			System.out.println( "sum: " + sum );
			
			
		}
		
		return (int)sum;
		
	}
	
	public int getCount_SomeBitsConstrained( int fieldLength, int bitsConstrained ){
		
		Vector<String> combos = new Vector<String>();
		
		String combo = "";
		
		int numberRows = fieldLength - bitsConstrained + 1;
		
		int numberCombosPerRow = (int) Math.pow( 2.0, ((double)numberRows) );
		
		// generate the portion of the binary strings that are "unconstrained" ..
		int unconstainedCount = 0;
		Vector<String> unconstrainedStrings = new Vector<String>();
		for(int i=0; i<numberRows; i++){
			
			unconstrainedStrings.add( Integer.toBinaryString( unconstainedCount ) );
			
		}
		
		String unconstrainedBitsLeft = "";
		String constrainedBits = "";
		String unconstrainedBitsRight = "";
		
		int unconstrainedBitsIndexStart = -1;
		int unconstrainedBitsIndexEnd = -1;
		int unconstrainedStringIndex = -1;
		
		// number of "rows" ..
		for(int i=0; i<numberRows; i++){
		
			// number of combos per "row" ..
			for(int j=0; j<numberCombosPerRow; j++){
				
				// a single combo ..
				
				// 1st row, #left_bits = null, 2nd row, #left_bits = 1, etc ..
				// 1st row, #right_bits = total, 2nd row, #right_bits = total - 1, etc ..
				unconstrainedBitsIndexStart = 0;
				unconstrainedBitsIndexEnd = i;
				unconstrainedStringIndex = 0;
				unconstrainedBitsLeft = unconstrainedStrings.get( unconstrainedStringIndex ).substring( unconstrainedBitsIndexStart, unconstrainedBitsIndexEnd );

				unconstrainedBitsRight = unconstrainedStrings.get( unconstrainedStringIndex ).substring( unconstrainedBitsIndexEnd, unconstrainedStrings.size() );
				
				// generate a combination ..
				// combo = constrained bits + unconstrained bits
				// more specifically,
				// combo = unconstrained bits (left) + constrained bits + unconstrained bits (right)
				// (where "left" and "right" have 0 or more bits) ..
				constrainedBits += unconstrainedBitsLeft;
				
				for(int k=0; k<fieldLength; k++){

					constrainedBits += "";

				}
				
				constrainedBits += unconstrainedBitsRight;
			
			}
			

			
			combos.add( combo );
			combo = new String();
			
		}
		
		return -1;
		
	}
	
	public static void main(String[] args){
		
		Driver d = new Driver();
		
		int value = d.convertBinaryToInt( "10000" );
		
		System.out.println( "value: " + value );
		
	}

}
