package speiger.src.collections.chars.collections;

import java.util.Collection;
import java.util.function.Supplier;
import java.util.Objects;
import java.util.AbstractCollection;

import speiger.src.collections.chars.lists.CharListIterator;
import speiger.src.collections.chars.functions.CharConsumer;
import speiger.src.collections.chars.utils.CharIterators;
import speiger.src.collections.chars.utils.CharArrays;

/**
 * Abstract Type Specific Collection that reduces boxing/unboxing
 */
public abstract class AbstractCharCollection extends AbstractCollection<Character> implements CharCollection
{
	@Override
	public abstract CharIterator iterator();
	
	/** {@inheritDoc}
	 * <p>This default implementation delegates to the corresponding type-specific function.
	 * @deprecated Please use the corresponding type-specific function instead. 
	 */
	@Override
	@Deprecated
	public boolean add(Character e) { return CharCollection.super.add(e); }

	@Override
	public boolean addAll(CharCollection c) {
		boolean modified = false;
		for(CharIterator iter = c.iterator();iter.hasNext();modified |= add(iter.nextChar()));
		return modified;
	}
	
	@Override
	public CharCollection copy() { throw new UnsupportedOperationException(); }
	
	/** {@inheritDoc}
	 * <p>This default implementation delegates to the corresponding type-specific function.
	 * @deprecated Please use the corresponding type-specific function instead. 
	 */
	@Override
	@Deprecated
	public boolean contains(Object e) { return CharCollection.super.contains(e); }
	
	/**
	 * A Type-Specific implementation of contains. This implementation iterates over the elements and returns true if the value match.
	 * @param e the element that should be searched for.
	 * @return true if the value was found.
	 */
	@Override
	public boolean contains(char e) {
		for(CharIterator iter = iterator();iter.hasNext();) { if(iter.nextChar() == e) return true; }
		return false;
	}
	
	/** {@inheritDoc}
	 * <p>This default implementation delegates to the corresponding type-specific function.
	 * @deprecated Please use the corresponding type-specific function instead. 
	 */
	@Override
	@Deprecated
	public boolean addAll(Collection<? extends Character> c)
	{
		return c instanceof CharCollection ? addAll((CharCollection)c) : super.addAll(c);
	}
	
	/**
	 * A Type-Specific implementation of containsAll. This implementation iterates over all elements and checks all elements are present in the other collection.
	 * @param c the collection that should be checked if it contains all elements.
	 * @return true if all elements were found in the collection
	 * @throws java.lang.NullPointerException if the collection is null
	 */
	@Override
	public boolean containsAll(CharCollection c) {
		Objects.requireNonNull(c);
		if(c.isEmpty()) return true;
		for(CharIterator iter = c.iterator();iter.hasNext();)
			if(!contains(iter.nextChar()))
				return false;
		return true;
	}
	
	@Override
	public boolean containsAll(Collection<?> c) {
		Objects.requireNonNull(c);
		return c instanceof CharCollection ? containsAll((CharCollection)c) : super.containsAll(c);
	}
	
	/**
	 * This implementation iterates over the elements of the collection and checks if they are stored in this collection
	 * @param c the elements that should be checked for
	 * @return true if any element is in this collection
	 * @throws java.lang.NullPointerException if the collection is null
	 */
	@Override
	@Deprecated
	public boolean containsAny(Collection<?> c) {
		Objects.requireNonNull(c);
		if(c.isEmpty()) return false;
		for(Object e : c) 
			if(contains(e))
				return true;
		return false;
	}
	
	/**
	 * This implementation iterates over the elements of the collection and checks if they are stored in this collection.
	 * @param c the elements that should be checked for
	 * @return true if any element is in this collection
 	 * @throws java.lang.NullPointerException if the collection is null
	 */
	@Override
	public boolean containsAny(CharCollection c) {
		Objects.requireNonNull(c);
		if(c.isEmpty()) return false;
		for(CharIterator iter = c.iterator();iter.hasNext();) 
			if(contains(iter.nextChar()))
				return true;
		return false;
	}
		
	/** {@inheritDoc}
	 * <p>This default implementation delegates to the corresponding type-specific function.
	 * @deprecated Please use the corresponding type-specific function instead. 
	 */
	@Override
	@Deprecated
	public boolean remove(Object e) { return CharCollection.super.remove(e); }
	
	/**
	 * A Type-Specific implementation of remove. This implementation iterates over the elements until it finds the element that is searched for or it runs out of elements.
	 * It stops after finding the first element
	 * @param e the element that is searched for
	 * @return true if the element was found and removed.
	 */
	@Override
	public boolean remChar(char e) {
		for(CharIterator iter = iterator();iter.hasNext();) {
			if(iter.nextChar() == e) {
				iter.remove();
				return true;
			}
		}
		return false;
	}
	
	/**
	 * A Type-Specific implementation of removeAll. This Implementation iterates over all elements and removes them as they were found in the other collection.
	 * @param c the elements that should be deleted
	 * @return true if the collection was modified.
	 * @throws java.lang.NullPointerException if the collection is null
	 */
	@Override
	public boolean removeAll(CharCollection c) {
		Objects.requireNonNull(c);
		if(c.isEmpty()) return false;
		boolean modified = false;
		for(CharIterator iter = iterator();iter.hasNext();) {
			if(c.contains(iter.nextChar())) {
				iter.remove();
				modified = true;
			}
		}
		return modified;
	}

	@Override
	public boolean removeAll(CharCollection c, CharConsumer r) {
		Objects.requireNonNull(c);
		if(c.isEmpty()) return false;
		Objects.requireNonNull(r);
		boolean modified = false;
		for(CharIterator iter = iterator();iter.hasNext();) {
			char e = iter.nextChar();
			if(c.contains(e)) {
				r.accept(e);
				iter.remove();
				modified = true;
			}
		}
		return modified;
	}
	
	/**
	 * A Type-Specific implementation of retainAll. This Implementation iterates over all elements and removes them as they were not found in the other collection.
	 * @param c the elements that should be kept
	 * @return true if the collection was modified.
	 * @throws java.lang.NullPointerException if the collection is null
	 */
	@Override
	public boolean retainAll(CharCollection c) {
		Objects.requireNonNull(c);
		if(c.isEmpty()) {
			boolean modified = !isEmpty();
			clear();
			return modified;
		}
		boolean modified = false;
		for(CharIterator iter = iterator();iter.hasNext();) {
			if(!c.contains(iter.nextChar())) {
				iter.remove();
				modified = true;
			}
		}
		return modified;
	}
	
	@Override
	public boolean retainAll(CharCollection c, CharConsumer r) {
		Objects.requireNonNull(c);
		Objects.requireNonNull(r);
		if(c.isEmpty()) {
			boolean modified = !isEmpty();
			forEach(r);
			clear();
			return modified;
		}
		boolean modified = false;
		for(CharIterator iter = iterator();iter.hasNext();) {
			char e = iter.nextChar();
			if(!c.contains(e)) {
				r.accept(e);
				iter.remove();
				modified = true;
			}
		}
		return modified;
	}
	
	/**
	 * A Type-Specific implementation of toArray that links to {@link #toCharArray(char[])} with a newly created array.
	 * @return an array containing all of the elements in this collection
	 */
	@Override
	public char[] toCharArray() {
		if(isEmpty()) return CharArrays.EMPTY_ARRAY;
		return toCharArray(new char[size()]);
	}
	
	/**
	 * A Type-Specific implementation of toArray. This implementation iterates over all elements and unwraps them into primitive type.
	 * @param a array that the elements should be injected to. If null or to small a new array with the right size is created
	 * @return an array containing all of the elements in this collection
	 */
	@Override
	public char[] toCharArray(char[] a) {
		if(a == null || a.length < size()) a = new char[size()];
		CharIterators.unwrap(a, iterator());
		if (a.length > size()) a[size()] = (char)0;
		return a;
	}

	public static class ReverseCharOrderedCollection extends AbstractCharCollection implements CharOrderedCollection {
		CharOrderedCollection collection;
		Supplier<CharIterator> reverseIterator;
		
		public ReverseCharOrderedCollection(CharOrderedCollection collection, Supplier<CharIterator> reverseIterator) {
			this.collection = collection;
			this.reverseIterator = reverseIterator;
		}
		
		@Override
		public boolean add(char o) { return collection.add(o); }
		@Override
		public CharOrderedCollection reversed() { return collection; }
		@Override
		public void addFirst(char e) { collection.addLast(e); }
		@Override
		public void addLast(char e) { collection.addFirst(e); }
		@Override
		public boolean contains(char e) { return collection.contains(e); }
		@Override
		public boolean remChar(char e) { return collection.remChar(e); }
		@Override
		public void clear() { collection.clear(); }
		@Override
		public char getFirstChar() { return collection.getLastChar(); }
		@Override
		public char removeFirstChar() { return collection.removeLastChar(); }
		@Override
		public char getLastChar() { return collection.getFirstChar(); }
		@Override
		public char removeLastChar() { return collection.removeFirstChar(); }
		@Override
		public CharIterator iterator() { return reverseIterator.get(); }
		@Override
		public int size() { return collection.size(); }
	}
	
	public static class ReverseBiIterator implements CharListIterator {
		CharListIterator it;
		
		public ReverseBiIterator(CharListIterator it) {
			this.it = it;
		}
		
		@Override
		public char nextChar() { return it.previousChar(); }
		@Override
		public boolean hasNext() { return it.hasPrevious(); }
		@Override
		public boolean hasPrevious() { return it.hasNext(); }
		@Override
		public char previousChar() { return it.nextChar(); }
		@Override
		public void remove() { it.remove(); }
		@Override
		public int nextIndex() { return it.previousIndex(); }
		@Override
		public int previousIndex() { return it.nextIndex(); }
		@Override
		public void set(char e) { it.set(e); }
		@Override
		public void add(char e) { it.add(e); }
	}
}