package speiger.src.collections.PACKAGE.utils;

import java.util.Collection;
import java.util.Objects;
import java.util.Random;
import java.util.RandomAccess;
import java.util.function.Consumer;

import speiger.src.collections.PACKAGE.collections.COLLECTION;
#if !TYPE_OBJECT
import speiger.src.collections.PACKAGE.functions.CONSUMER;
#endif
import speiger.src.collections.PACKAGE.lists.ABSTRACT_LIST;
import speiger.src.collections.PACKAGE.lists.LIST;
import speiger.src.collections.PACKAGE.lists.LIST_ITERATOR;
import speiger.src.collections.PACKAGE.utils.ARRAYS;
import speiger.src.collections.utils.SanityChecks;

/**
 * A Helper class for Lists
 */
public class LISTS
{
	/**
	 * Empty List reference
	 */
	public static final EmptyList NO_GENERIC_TYPE EMPTY = new EmptyListBRACES();
	
	/**
	 * Returns a Immutable EmptyList instance that is automatically casted.
	 * @Type(T)
	 * @return an empty list
	 */
	public static GENERIC_KEY_BRACES EmptyList KEY_GENERIC_TYPE empty() {
#if TYPE_OBJECT
		return (EmptyList<KEY_TYPE>)EMPTY;
#else
		return EMPTY;
#endif
	}
	
	/**
	 * Returns a Immutable List instance based on the instance given.
	 * @param l that should be made immutable/unmodifiable
	 * @Type(T)
	 * @return a unmodifiable list wrapper. If the list is implementing RandomAccess that is also transferred. If the List already a unmodifiable wrapper then it just returns itself.
	 */
	public static GENERIC_KEY_BRACES LIST KEY_GENERIC_TYPE unmodifiable(LIST KEY_GENERIC_TYPE l) {
		return l instanceof UnmodifiableList ? l : l instanceof RandomAccess ? new UnmodifiableRandomListBRACES(l) : new UnmodifiableListBRACES(l);
	}
	
	/**
	 * Returns a synchronized List instance based on the instance given.
	 * @param l that should be synchronized
	 * @Type(T)
	 * @return a synchronized list wrapper. If the list is implementing RandomAccess or IARRAY that is also transferred. If the List already a synchronized wrapper then it just returns itself.
	 */
	public static GENERIC_KEY_BRACES LIST KEY_GENERIC_TYPE synchronize(LIST KEY_GENERIC_TYPE l) {
		return l instanceof SynchronizedList ? l : (l instanceof IARRAY ? new SynchronizedArrayListBRACES(l) : (l instanceof RandomAccess ? new SynchronizedRandomAccessListBRACES(l) : new SynchronizedListBRACES(l)));
	}
	
	/**
	 * Returns a synchronized List instance based on the instance given.
	 * @param l that should be synchronized
	 * @param mutex is the controller of the synchronization block.
	 * @Type(T)
	 * @return a synchronized list wrapper. If the list is implementing RandomAccess or IARRAY that is also transferred. If the List already a synchronized wrapper then it just returns itself.
	 */
	public static GENERIC_KEY_BRACES LIST KEY_GENERIC_TYPE synchronize(LIST KEY_GENERIC_TYPE l, Object mutex) {
		return l instanceof SynchronizedList ? l : (l instanceof IARRAY ? new SynchronizedArrayListBRACES(l, mutex) : (l instanceof RandomAccess ? new SynchronizedRandomAccessListBRACES(l, mutex) : new SynchronizedListBRACES(l, mutex)));
	}
	
	/**
	 * Creates a Unmodifiable Singleton list
	 * @param element that should be used in the Singleton
	 * @Type(T)
	 * @return a singleton list that is unmodifiable
	 */
	public static GENERIC_KEY_BRACES LIST KEY_GENERIC_TYPE singleton(KEY_TYPE element) {
		return new SingletonListBRACES(element);
	}
	
	/**
	 * Reverses the list
	 * @param list that should be reversed.
	 * @Type(T)
	 * @return the input list
	 */
	public static GENERIC_KEY_BRACES LIST KEY_GENERIC_TYPE reverse(LIST KEY_GENERIC_TYPE list) {
		int size = list.size();
		if(list instanceof IARRAY) {
			IARRAY KEY_GENERIC_TYPE array = (IARRAY KEY_GENERIC_TYPE)list;
#if TYPE_OBJECT
			if(array.isCastable()) {
				if(list instanceof SynchronizedArrayList) array.elements(T -> ARRAYS.reverse(T, size));
				else ARRAYS.reverse(array.elements(), size);
				return list;
			}
#else
			if(list instanceof SynchronizedArrayList) array.elements(T -> ARRAYS.reverse(T, size));
			else ARRAYS.reverse(array.elements(), size);
			return list;
#endif
		}
		if(list instanceof RandomAccess) {
			for (int i = 0, mid = size >> 1, j = size - 1; i < mid; i++, j--) {
				KEY_TYPE t = list.GET_KEY(i);
				list.set(i, list.GET_KEY(j));
				list.set(j, t);
			}
			return list;
		}
		LIST_ITERATOR KEY_GENERIC_TYPE fwd = list.listIterator();
		LIST_ITERATOR KEY_GENERIC_TYPE rev = list.listIterator(size);
		for(int i = 0, mid = size >> 1; i < mid; i++) {
			KEY_TYPE tmp = fwd.NEXT();
			fwd.set(rev.PREVIOUS());
			rev.set(tmp);
		}
		return list;
	}
	
	/**
	 * Shuffles the list
	 * @param list that should be Shuffled.
	 * @Type(T)
	 * @return the input list
	 */
	public static GENERIC_KEY_BRACES LIST KEY_GENERIC_TYPE shuffle(LIST KEY_GENERIC_TYPE list) {
		return shuffle(list, SanityChecks.getRandom());
	}
	
	/**
	 * Shuffles the list
	 * @param list that should be Shuffled.
	 * @param random the random that should be used
	 * @Type(T)
	 * @return the input list
	 */
	public static GENERIC_KEY_BRACES LIST KEY_GENERIC_TYPE shuffle(LIST KEY_GENERIC_TYPE list, Random random) {
		int size = list.size();
		if(list instanceof IARRAY) {
			IARRAY KEY_GENERIC_TYPE array = (IARRAY KEY_GENERIC_TYPE)list;
#if TYPE_OBJECT
			if(array.isCastable()) {
				if(list instanceof SynchronizedArrayList) array.elements(T -> ARRAYS.shuffle(T, size, random));
				else ARRAYS.shuffle(array.elements(), size, random);
			}
			else {
				for(int i = list.size(); i-- != 0;) {
					int p = random.nextInt(i + 1);
					KEY_TYPE t = list.GET_KEY(i);
					list.set(i, list.GET_KEY(p));
					list.set(p, t);
				}
			}
#else
			if(list instanceof SynchronizedArrayList)  array.elements(T -> ARRAYS.shuffle(T, size, random));
			else ARRAYS.shuffle(array.elements(), size, random);
#endif
			return list;
		}
		for(int i = list.size(); i-- != 0;) {
			int p = random.nextInt(i + 1);
			KEY_TYPE t = list.GET_KEY(i);
			list.set(i, list.GET_KEY(p));
			list.set(p, t);
		}
		return list;
	}
	
	private static class SingletonList KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_TYPE
	{
		KEY_TYPE element;
		
		SingletonList(KEY_TYPE element)
		{
			this.element = element;
		}
		@Override
		public void add(int index, KEY_TYPE e) { throw new UnsupportedOperationException(); }
		@Override
		public boolean addAll(int index, Collection<? extends CLASS_TYPE> c) { throw new UnsupportedOperationException(); }
		@Override
		public boolean addAll(int index, COLLECTION KEY_GENERIC_TYPE c) { throw new UnsupportedOperationException(); }
		@Override
		public boolean addAll(int index, LIST KEY_GENERIC_TYPE c) { throw new UnsupportedOperationException(); }

		@Override
		public KEY_TYPE GET_KEY(int index) {
			if(index == 0) return element;
			throw new IndexOutOfBoundsException();
		}
		
		@Override
		public KEY_TYPE set(int index, KEY_TYPE e) { throw new UnsupportedOperationException(); }
		@Override
		public KEY_TYPE REMOVE(int index) { throw new UnsupportedOperationException(); }
		@Override
		public void addElements(int from, KEY_TYPE[] a, int offset, int length) { throw new UnsupportedOperationException(); }
		@Override
		public KEY_TYPE[] getElements(int from, KEY_TYPE[] a, int offset, int length) {
			if(from != 0 || length != 1) throw new IndexOutOfBoundsException();
			a[offset] = element;
			return a;
		}

		@Override
		public void removeElements(int from, int to) { throw new UnsupportedOperationException(); }
#if TYPE_OBJECT
		@Override
		public <K> K[] extractElements(int from, int to, Class<K> type) { throw new UnsupportedOperationException(); }
#else
		@Override
		public KEY_TYPE[] extractElements(int from, int to) { throw new UnsupportedOperationException(); }
#endif
		@Override
		public int size() { return 1; }
	}
	
	private static class SynchronizedArrayList KEY_GENERIC_TYPE extends SynchronizedList KEY_GENERIC_TYPE implements IARRAY KEY_GENERIC_TYPE
	{
		IARRAY KEY_GENERIC_TYPE l;
		
		SynchronizedArrayList(LIST KEY_GENERIC_TYPE l) {
			super(l);
			this.l = (IARRAY KEY_GENERIC_TYPE)l;
		}
		
		SynchronizedArrayList(LIST KEY_GENERIC_TYPE l, Object mutex) {
			super(l, mutex);
			this.l = (IARRAY KEY_GENERIC_TYPE)l;
		}
		
		@Override
		public void ensureCapacity(int size) { synchronized(mutex) { l.ensureCapacity(size); } }
		
		@Override
		public boolean trim(int size) { synchronized(mutex) { return l.trim(size); } }
		
		@Override
		public void clearAndTrim(int size) { synchronized(mutex) { l.clearAndTrim(size); } }
		
		@Override
		public KEY_TYPE[] elements() { synchronized(mutex) { return l.elements(); } }
		
#if TYPE_OBJECT
		@Override
		public boolean isCastable() { synchronized(mutex) { return l.isCastable(); } }
		
#endif		
		@Override
		public void elements(Consumer<KEY_TYPE[]> action) { 
			Objects.requireNonNull(action);
			synchronized(mutex) {
				l.elements(action);
			}
		}
	}
	
	private static class SynchronizedRandomAccessList KEY_GENERIC_TYPE extends SynchronizedList KEY_GENERIC_TYPE implements RandomAccess 
	{
		SynchronizedRandomAccessList(LIST KEY_GENERIC_TYPE l) {
			super(l);
		}
		
		SynchronizedRandomAccessList(LIST KEY_GENERIC_TYPE l, Object mutex) {
			super(l, mutex);
		}
	}
	
	private static class SynchronizedList KEY_GENERIC_TYPE extends COLLECTIONS.SynchronizedCollection KEY_GENERIC_TYPE implements LIST KEY_GENERIC_TYPE
	{
		LIST KEY_GENERIC_TYPE l;
		
		SynchronizedList(LIST KEY_GENERIC_TYPE l) {
			super(l);
			this.l = l;
		}
		
		SynchronizedList(LIST KEY_GENERIC_TYPE l, Object mutex) {
			super(l, mutex);
			this.l = l;
		}
		
		@Override
		public boolean addAll(int index, Collection<? extends CLASS_TYPE> c) { synchronized(mutex) { return l.addAll(index, c); } }
		
		@Override
		public void add(int index, CLASS_TYPE element) { synchronized(mutex) { l.add(index, element); } }
		
#if !TYPE_OBJECT
		@Override
		public void add(int index, KEY_TYPE e) { synchronized(mutex) { l.add(index, e); } }
		
#endif
		@Override
		public boolean addAll(int index, COLLECTION KEY_GENERIC_TYPE c) { synchronized(mutex) { return l.addAll(index, c); } }
		
		@Override
		public boolean addAll(LIST KEY_GENERIC_TYPE c) { synchronized(mutex) { return l.addAll(c); } }
		
		@Override
		public boolean addAll(int index, LIST KEY_GENERIC_TYPE c) { synchronized(mutex) { return l.addAll(index, c); } }
		
		@Override
		public KEY_TYPE GET_KEY(int index) { synchronized(mutex) { return l.GET_KEY(index); } }
		
#if !TYPE_OBJECT
		@Override
		public void forEach(CONSUMER action) { synchronized(mutex) { l.forEach(action); } }
		
#else 
		@Override
		public void forEach(Consumer<? super KEY_TYPE> action) { synchronized(mutex) { l.forEach(action); } }
		
#endif
		@Override
		public KEY_TYPE set(int index, KEY_TYPE e) { synchronized(mutex) { return l.set(index, e); } }
		
		@Override
		public KEY_TYPE REMOVE(int index) { synchronized(mutex) { return l.REMOVE(index); } }
		
		@Override
		@Primitive
		public int indexOf(Object e) { synchronized(mutex) { return l.indexOf(e); } }
		
		@Override
		@Primitive
		public int lastIndexOf(Object e) { synchronized(mutex) { return l.lastIndexOf(e); } }
				
#if !TYPE_OBJECT
		@Override
		public int indexOf(KEY_TYPE e) { synchronized(mutex) { return l.indexOf(e); } }
		
		@Override
		public int lastIndexOf(KEY_TYPE e) { synchronized(mutex) { return l.lastIndexOf(e); } }
		
#endif
		@Override
		public void addElements(int from, KEY_TYPE[] a, int offset, int length) { synchronized(mutex) { addElements(from, a, offset, length); } }
		
		@Override
		public KEY_TYPE[] getElements(int from, KEY_TYPE[] a, int offset, int length) { synchronized(mutex) { return l.getElements(from, a, offset, length); } }
		
		@Override
		public void removeElements(int from, int to) { synchronized(mutex) { l.removeElements(from, to); } }
		
#if !TYPE_OBJECT
		@Override
		public KEY_TYPE[] extractElements(int from, int to) { synchronized(mutex) { return l.extractElements(from, to); } }
		
#else
		@Override
		public <K> K[] extractElements(int from, int to, Class<K> clz) { synchronized(mutex) { return l.extractElements(from, to, clz); } }
		
#endif
		@Override
		public LIST_ITERATOR KEY_GENERIC_TYPE listIterator() {
			return l.listIterator();
		}
		
		@Override
		public LIST_ITERATOR KEY_GENERIC_TYPE listIterator(int index) {
			return l.listIterator(index);
		}
		
		@Override
		public LIST KEY_GENERIC_TYPE subList(int from, int to) {
			return synchronize(l.subList(from, to));
		}
		
		@Override
		public void size(int size) { synchronized(mutex) { l.size(size); } }
	}
	
	private static class UnmodifiableRandomList KEY_GENERIC_TYPE extends UnmodifiableList KEY_GENERIC_TYPE implements RandomAccess 
	{
		UnmodifiableRandomList(LIST KEY_GENERIC_TYPE l) {
			super(l);
		}
	}
	
	private static class UnmodifiableList KEY_GENERIC_TYPE extends COLLECTIONS.UnmodifiableCollection KEY_GENERIC_TYPE implements LIST KEY_GENERIC_TYPE
	{
		final LIST KEY_GENERIC_TYPE l;
		
		UnmodifiableList(LIST KEY_GENERIC_TYPE l) {
			super(l);
			this.l = l;
		}
		
		@Override
		public boolean addAll(int index, Collection<? extends CLASS_TYPE> c) { throw new UnsupportedOperationException(); }
		
		@Override
		public void add(int index, CLASS_TYPE element) { throw new UnsupportedOperationException(); }
		
#if !TYPE_OBJECT
		@Override
		public void add(int index, KEY_TYPE e) { throw new UnsupportedOperationException(); }
		
#endif
		@Override
		public boolean addAll(int index, COLLECTION KEY_GENERIC_TYPE c) { throw new UnsupportedOperationException(); }
		
		@Override
		public boolean addAll(LIST KEY_GENERIC_TYPE c) { throw new UnsupportedOperationException(); }
		
		@Override
		public boolean addAll(int index, LIST KEY_GENERIC_TYPE c) { throw new UnsupportedOperationException(); }
		
		@Override
		public KEY_TYPE GET_KEY(int index) { return l.GET_KEY(index); }
		
#if !TYPE_OBJECT
		@Override
		public void forEach(CONSUMER action) { l.forEach(action); }
		
#else 
		@Override
		public void forEach(Consumer<? super KEY_TYPE> action) { l.forEach(action); }
		
#endif
		@Override
		public KEY_TYPE set(int index, KEY_TYPE e) { throw new UnsupportedOperationException(); }
		
		@Override
		public KEY_TYPE REMOVE(int index) { throw new UnsupportedOperationException(); }
		
		@Override
		@Primitive
		public int indexOf(Object e) { return l.indexOf(e); }
		
		@Override
		@Primitive
		public int lastIndexOf(Object e) { return l.lastIndexOf(e); }
				
#if !TYPE_OBJECT
		@Override
		public int indexOf(KEY_TYPE e) { return l.indexOf(e); }
		
		@Override
		public int lastIndexOf(KEY_TYPE e) { return l.lastIndexOf(e); }
		
#endif
		@Override
		public void addElements(int from, KEY_TYPE[] a, int offset, int length) { throw new UnsupportedOperationException(); }
		
		@Override
		public KEY_TYPE[] getElements(int from, KEY_TYPE[] a, int offset, int length) {
			return l.getElements(from, a, offset, length);
		}
		
		@Override
		public void removeElements(int from, int to) { throw new UnsupportedOperationException(); }
		
#if !TYPE_OBJECT
		@Override
		public KEY_TYPE[] extractElements(int from, int to) { throw new UnsupportedOperationException(); }
		
#else
		@Override
		public <K> K[] extractElements(int from, int to, Class<K> clz) { throw new UnsupportedOperationException(); }
		
#endif
		@Override
		public LIST_ITERATOR KEY_GENERIC_TYPE listIterator() {
			return ITERATORS.unmodifiable(l.listIterator());
		}
		
		@Override
		public LIST_ITERATOR KEY_GENERIC_TYPE listIterator(int index) {
			return ITERATORS.unmodifiable(l.listIterator(index));
		}
		
		@Override
		public LIST KEY_GENERIC_TYPE subList(int from, int to) {
			return unmodifiable(l.subList(from, to));
		}
		
		@Override
		public void size(int size) { throw new UnsupportedOperationException(); }
	}
	
	private static class EmptyList KEY_GENERIC_TYPE extends COLLECTIONS.EmptyCollection KEY_GENERIC_TYPE implements LIST KEY_GENERIC_TYPE
	{
		@Override
		public boolean addAll(int index, Collection<? extends CLASS_TYPE> c) { throw new UnsupportedOperationException(); }
		
		@Override
		public void add(int index, CLASS_TYPE element) { throw new UnsupportedOperationException(); }
		
#if !TYPE_OBJECT
		@Override
		public void add(int index, KEY_TYPE e) { throw new UnsupportedOperationException(); }
		
#endif
		@Override
		public boolean addAll(int index, COLLECTION KEY_GENERIC_TYPE c) { throw new UnsupportedOperationException(); }
		
		@Override
		public boolean addAll(LIST KEY_GENERIC_TYPE c) { throw new UnsupportedOperationException(); }
		
		@Override
		public boolean addAll(int index, LIST KEY_GENERIC_TYPE c) { throw new UnsupportedOperationException(); }
		
		@Override
		public KEY_TYPE GET_KEY(int index) { throw new IndexOutOfBoundsException(); }
		
		@Override
		public KEY_TYPE set(int index, KEY_TYPE e) { throw new UnsupportedOperationException(); }
		
		@Override
		public KEY_TYPE REMOVE(int index) { throw new UnsupportedOperationException(); }
		
		@Override
		public int indexOf(Object e) { return -1; }
		
		@Override
		public int lastIndexOf(Object e) { return -1; }
				
#if !TYPE_OBJECT
		@Override
		public int indexOf(KEY_TYPE e) { return -1; }
		
		@Override
		public int lastIndexOf(KEY_TYPE e) { return -1; }
		
#endif
		@Override
		public void addElements(int from, KEY_TYPE[] a, int offset, int length){ throw new UnsupportedOperationException(); }
		
		@Override
		public KEY_TYPE[] getElements(int from, KEY_TYPE[] a, int offset, int length) { throw new IndexOutOfBoundsException(); }
		
		@Override
		public void removeElements(int from, int to) { throw new UnsupportedOperationException(); }
		
#if !TYPE_OBJECT
		@Override
		public KEY_TYPE[] extractElements(int from, int to) { throw new UnsupportedOperationException(); }
		
#else
		@Override
		public <K> K[] extractElements(int from, int to, Class<K> clz) { throw new UnsupportedOperationException(); }

#endif
		@Override
		public LIST_ITERATOR KEY_GENERIC_TYPE listIterator() {
			return ITERATORS.empty();
		}
		
		@Override
		public LIST_ITERATOR KEY_GENERIC_TYPE listIterator(int index) {
			if(index != 0)
				throw new IndexOutOfBoundsException();
			return ITERATORS.empty();
		}
		
		@Override
		public LIST KEY_GENERIC_TYPE subList(int from, int to) { throw new UnsupportedOperationException(); }
		
		@Override
		public void size(int size) { throw new UnsupportedOperationException(); }
	}
}