/**
 *
 * @author Casey Jackson
 */
public class HydraList{

    private letterNode h; //list Header
    private dataNode g; //dataList header
    public HydraList()
    {
        h = new letterNode();
        //g = new dataNode();
        //g.next = null;
        //g.data = null;
        //g.partNum = null;
        h.letter = ' ';
        h.next = null;
        h.data = null;
    }

    public void insert(AutoPart newPart)
    {
        letterNode p = h.next;
        letterNode q = h;
        char x =  newPart.getPartNumber().charAt(0);
        while(p != null && p.letter != x)
        {
            q = p;
            p = p.next;
        }
        if (p != null)
        {
           dataNode b = q.data;
           if(b != null)
           {
               dataNode a = b.next;
               while(q.data != null)
               {
                   b = a;
                   a = a.next;
               }
               if (a != null)
               {
                   dataNode z = new dataNode();
                   z = a.next;
                   a.next = z;
                   z.data = newPart.deepCopy();
                   z.partNum = newPart.getPartNumber();
               }
               else
               {
                    dataNode z = new dataNode();
                    z = a.next;                               // this line throws the null pointer exception, because a==null (ref: if-condition)
                    a.next = z;
                    z.data = newPart.deepCopy();
                    z.partNum = newPart.getPartNumber();
               }
            }
        }
        else
        {
            p = h.next;                           // what is this for?
            letterNode n = new letterNode();
            n.next = q.next;                      // will not sort. just building a list
            q.next = n;                           // at least it's a 'pure' insert (always at beginning)
            n.letter = x;
            dataNode z = new dataNode();
            z.next = n.data;                      // also will not sort...
            z.data = newPart.deepCopy();
            z.partNum = newPart.getPartNumber();
            n.data = z;                           // above commented line + this one will always insert at beginning
        }
}

//

//    public void insert(AutoPart newPart)
//    {
//        letterNode p = new letterNode();
//        letterNode q = new letterNode();
//        q = h;
//        p = h.next;
//        dataNode o = new dataNode();
//        char x =  newPart.getPartNumber().charAt(0);
//        if(letterIsEmpty())
//        {
//            letterNode n = new letterNode();
//            n.next = h.next;
//            h.next = n;
//            n.letter = newPart.getPartNumber().charAt(0);
//            o.next = n.data;
//            n.data = o;
//            o.partNum = newPart.getPartNumber();
//            o.data = newPart.deepCopy();
//        }
//        else
//        {
//            while(p != null && p.letter != x)
//            {
//                q = p;
//                p = p.next;
//            }
//            if(p != null)
//            {
//                if(p.data == null)
//                {
//                    o.next = p.data;
//                    p.data = o;
//                    o.data = newPart.deepCopy();
//                    o.partNum = newPart.getPartNumber();
//                }
//            else
//                {
//                    //dataNode z = new dataNode();
//                    dataNode z = q.data;
//                    while(g!= null && !(g.partNum.compareTo
//                            (newPart.getPartNumber()) == 0))
//                    {
//                        g = g.next;
//                    }
//                    if(g != null)
//                    {
//                        o.next = g.next;
//                        g.next = o;
//                        o.data = newPart.deepCopy();
//                        o.partNum = newPart.getPartNumber();
//                    }
//                }
//            }
//        }
//    }



    public AutoPart fetch(String targetPart)
    {
        letterNode a = h.next;
        while(a != null && a.letter != targetPart.charAt(0))
        {
            a = a.next;
        }
        if (a != null)
        {
            dataNode b = h.data;
            while(b != null && !(b.partNum.compareTo(targetPart) == 0))
            {
                b = b.next;
            }
            if (b != null)
            {
                return b.data.deepCopy();
            }
            else
                return null;
        }
        else
        {
            return null;
        }
    }

    public boolean delete(String targetPart)
    {
        letterNode b = h;
        letterNode a = h.next;
        while( a != null && a.letter != targetPart.charAt(0))
        {
            b = a;
            a = a.next;
        }
        if( a != null)
        {
            dataNode d = a.data;
            dataNode c = d.next;
            while(c != null && !(c.partNum.compareTo(targetPart) == 0))
            {
                d = c;
                c = c.next;
            }
            if (c != null)
            {
                d.next = c.next;
                if (a.data == null)
                {
                    b.next = a.next;
                }
                return true;
            }
            else
                return false;
        }
        else
            return false;
        }

    public boolean update(String targetPart, float newPrice, int inStock)
    {
        AutoPart x = fetch(targetPart);
        if(x == null)
        {
            return false;
        }
        else
        {
            x.setPrice(newPrice);
            x.setNumInStock(inStock);
            return true;
        }
    }


//    public void print()
//    {
//        letterNode p = h.next;
//        dataNode q = p.data;
//        while(p != null)
//        {
//            while(q != null)
//            {
//                System.out.println(q.data);
//                q = q.next;
//            }
//            p = p.next;
//        }
//    }


    public void print()
    {
        letterNode q = h;
        letterNode p = h.next;
        //dataNode a = p.data;
        while(p != null)
        {
            dataNode a = p.data;
            while(q != null)
            {
                System.out.println(q.data);
                q = q.next;
            }
            p = p.next;
        }
    }


    public boolean letterIsEmpty()
    {
        boolean empty = false;
        if(h.next == null){
            empty = true;
        }
        return empty;
    }

    public class letterNode{
        private char letter;
        private letterNode next;
        private dataNode data;
        public letterNode(){

        }

    }

    public class dataNode{
        private AutoPart data;
        private String partNum;
        private dataNode next;
        public dataNode()
        {
        }
    }
}