#include "caching/metadata.h"
#include "persistent-data/space-maps/core.h"

using namespace caching;

//----------------------------------------------------------------

namespace {
	using namespace superblock_detail;

	unsigned const METADATA_CACHE_SIZE = 1024;

	// FIXME: duplication
	transaction_manager::ptr
	open_tm(block_manager<>::ptr bm) {
		space_map::ptr sm(new core_map(bm->get_nr_blocks()));
		sm->inc(SUPERBLOCK_LOCATION);
		transaction_manager::ptr tm(new transaction_manager(bm, sm));
		return tm;
	}

	void
	copy_space_maps(space_map::ptr lhs, space_map::ptr rhs) {
		for (block_address b = 0; b < rhs->get_nr_blocks(); b++) {
			uint32_t count = rhs->get_count(b);
			if (count > 0)
				lhs->set_count(b, rhs->get_count(b));
		}
	}

	void init_superblock(superblock &sb) {
#if 0
		sb.magic_ = SUPERBLOCK_MAGIC;
		sb.version_ = 1;
		sb.data_mapping_root_ = mappings_->get_root();
		sb.device_details_root_ = details_->get_root();
		sb.data_block_size_ = data_block_size;
		sb.metadata_block_size_ = MD_BLOCK_SIZE;
		sb.metadata_nr_blocks_ = tm_->get_bm()->get_nr_blocks();
#endif
	}
}

//----------------------------------------------------------------

metadata::metadata(block_manager<>::ptr bm, open_type ot)
{
	switch (ot) {
	case OPEN:
		throw runtime_error("not implemented");
		break;

	case CREATE:
		tm_ = open_tm(bm);
		space_map::ptr core = tm_->get_sm();
		metadata_sm_ = create_metadata_sm(tm_, tm_->get_bm()->get_nr_blocks());
		copy_space_maps(metadata_sm_, core);
		tm_->set_sm(metadata_sm_);

		mappings_ = mapping_array::ptr(new mapping_array(tm_, mapping_array::ref_counter()));
//		hints_ = hint_array::ptr(new hint_array(tm_));

		::memset(&sb_, 0, sizeof(sb_));
		init_superblock(sb_);
	}
}

void
metadata::commit()
{
	metadata_sm_->commit();
	metadata_sm_->copy_root(&sb_.metadata_space_map_root, sizeof(sb_.metadata_space_map_root));
	sb_.mapping_root = mappings_->get_root();

	write_ref superblock = tm_->get_bm()->superblock_zero(SUPERBLOCK_LOCATION, superblock_validator());
	superblock_disk *disk = reinterpret_cast<superblock_disk *>(superblock.data().raw());
	superblock_traits::pack(sb_, *disk);
}

//----------------------------------------------------------------