/**
 * @file BufferTop.c
 */

#include "cgds/BufferTop.h"

// NOTE: no _init() method here, since BufferTop has no specific initialization

BufferTop* _buffertop_new(size_t dataSize, UInt capacity, OrderType bType, UInt arity)
{
	BufferTop* bufferTop = (BufferTop*) safe_malloc(sizeof (BufferTop));
	bufferTop->capacity = capacity;
	bufferTop->bType = bType; //redondant, but facilitate understanding
	// WARNING: heap must have opposite type: "smallest" element first
	bufferTop->heap = _heap_new(dataSize, (bType == MAX_T ? MIN_T : MAX_T), arity);
	return bufferTop;
}

BufferTop* buffertop_copy(BufferTop* bufferTop)
{
	BufferTop* bufferTopCopy = _buffertop_new(
		bufferTop->heap->dataSize, bufferTop->capacity,
		bufferTop->heap->hType, bufferTop->heap->arity);
	heap_destroy(bufferTopCopy->heap); //TODO: bad style...
	bufferTopCopy->heap = heap_copy(bufferTop->heap);
	return bufferTopCopy;
}

List* buffertop_2list(BufferTop* bufferTop)
{
	// Copy the buffer, and then use the copy to build the list
	BufferTop* bufferTopCopy = buffertop_copy(bufferTop);
	List* bufferInList = _list_new(bufferTop->heap->array->dataSize);
	while (!buffertop_empty(bufferTopCopy))
	{
		void* topItem = buffertop_first_raw(bufferTopCopy)->item;
		// NOTE: list_insert_front(), to reverse (wrong) items order
		// ==> in the returned list, top element is at head.
		_list_insert_front(bufferInList, topItem);
		buffertop_pop(bufferTopCopy);
	}
	buffertop_destroy(bufferTopCopy);
	return bufferInList;
}

Bool buffertop_empty(BufferTop* bufferTop)
{
	return (heap_size(bufferTop->heap) == 0);
}

UInt buffertop_size(BufferTop* bufferTop)
{
	return heap_size(bufferTop->heap);
}

void _buffertop_tryadd(BufferTop* bufferTop, void* item, Real value)
{
	if (heap_size(bufferTop->heap) >= bufferTop->capacity &&
		((bufferTop->bType == MIN_T &&
		value >= ((ItemValue*) (bufferTop->heap->array->datas[0]))->value)
		||
		(bufferTop->bType == MAX_T &&
		value <= ((ItemValue*) (bufferTop->heap->array->datas[0]))->value)))
	{
		// shortcut : if value "worse" than top->value and buffer is full, skip
		return;
	}

	// insertion somewhere in the item-values heap
	_heap_insert(bufferTop->heap, item, value);

	if (heap_size(bufferTop->heap) > bufferTop->capacity)
		// we must remove current root
		heap_pop(bufferTop->heap);
}

ItemValue* buffertop_first_raw(BufferTop* bufferTop)
{
	return heap_top_raw(bufferTop->heap);
}

void buffertop_pop(BufferTop* bufferTop)
{
	heap_pop(bufferTop->heap);
}

void buffertop_clear(BufferTop* bufferTop)
{
	heap_clear(bufferTop->heap);
}

void buffertop_destroy(BufferTop* bufferTop)
{
	heap_destroy(bufferTop->heap);
	safe_free(bufferTop);
}