#include "storage.h"
#include "bitset.h"

component_pair_t *
findPair(storage_t *this, const char *name)
{
	for (int i = 0; i < this->componentsStored; ++i)
	{
		component_pair_t *pair = &this->objects[i];
		if (strcmp(name, pair->name) == 0)
		{
			return pair;
		}
	}
	return NULL;
}

entity_t
createEntity(storage_t *this)
{
	entity_t idx = this->objectsStored++;
	for (int i = 0; i < this->componentsStored; ++i)
	{
		component_pair_t pair = this->objects[i];
		memset(&pair.objects[idx], 0, pair.objectSize);
	}
	return idx;
}

void
registerSystem(storage_t *storage, system_t system, bitset_t components)
{
	int idx = storage->systemsStored++;
	storage->systems[idx] = system;
	bitarena_copy(&storage->systemSignatures, components, idx);
}

bitset_t
createSignature(storage_t *storage, char **components)
{
	bitset_t bitset = bitset_create();

	for (int i = 0; components[i] != NULL; ++i)
	{
		const char *componentName = components[i];
		component_pair_t *pair = findPair(storage, componentName);
		if (pair == NULL)
		{
			return NULL;
		}
		else
		{
			bitset_set(bitset, pair->idx);
		}
	}
	return bitset;
}

// Not intended for use outside of macros
void
internal_registerComponent(storage_t *storage, const char *name, size_t size)
{
	unsigned int componentIdx = storage->componentsStored++;
	storage->objects[componentIdx] = (component_pair_t) {
		.idx = componentIdx,
		.name = name,
		.objectSize = size,
		.objects = malloc(sizeof(char) * size * MAX_OBJECTS)
	};
}

void * // NULL if component with such name is not found
internal_addComponent(storage_t *this, entity_t idx, const char *name)
{
	component_pair_t *pair = findPair(this, name);
	if (pair == NULL) 
	{
		return NULL;
	}

	// TODO: add bitset implementation
	bitset_t bitset = bitarena_at(&this->objectSignatures, idx);
	bitset_set(bitset, pair->idx);

	return &pair->objects[idx];
}

// Not intended for use outside of macros
void * // NULL if component is not found
internal_getComponent(storage_t *this, entity_t idx, const char *name)
{
	for (int i = 0; i < this->componentsStored; ++i)
	{
		component_pair_t *pair = &this->objects[i];
		if (strcmp(name, pair->name) == 0)
		{
			return &pair->objects[idx];
		}
	}
	return NULL;
}