#include <stdint.h>
#include <kernel/fs/ata_pio.h>
#include <kernel/fs/marfs/marfs.h>
#include <kernel/memory/alloc.h>

static uint8_t last_max_level = 0;

void marfs_update_recursive(uint8_t level, uint32_t i, uint32_t rec_lba, uint32_t real_lba)
{
	if (level > last_max_level)
		last_max_level = level;
	uint32_t *contents = (uint32_t *)ata_read28(interface, rec_lba);

	uint32_t idx = i - 10;
	if (last_max_level > 1)
		idx -= 1 << 7;
	if (last_max_level > 2)
		idx -= 1 << (7 * 2);
	if (last_max_level > 3)
		idx -= 1 << (7 * 3);
	idx >>= 7 * (level - 1);

	if (level > 1) {
		if (!contents[idx]) {
			contents[idx] = marfs_get_free_lba_block();
			marfs_mark_block_as_used(contents[idx]);
		}
	} else {
		contents[idx] = real_lba;
	}

	ata_write28(interface, rec_lba, (uint8_t *)contents);

	uint32_t contents_idx = contents[idx];
	kfree(contents);
	if (level != 1) {
		marfs_update_recursive((uint8_t)(level - 1), i, contents_idx, real_lba);
	}
	last_max_level = 0;
}

uint32_t marfs_new_file(uint64_t size, uint8_t *data, uint32_t uid, uint8_t exec, uint8_t dir)
{
	struct marfs_inode *inode = (struct marfs_inode *)kmalloc(512);
	inode->size = size;
	inode->creation_time = inode->last_mod_time = inode->last_access_time =
		0; // TODO: POSIX time
	inode->n_blocks = (uint32_t)(size / 512);
	if (size % 512)
		inode->n_blocks++;
	inode->uid = uid;
	inode->is_app = exec;
	inode->is_dir = dir;
	inode->is_used = 1;

	uint32_t size_in_blocks = inode->n_blocks;

	uint32_t lba_singly, lba_doubly, lba_triply, lba_quadruply;
	lba_singly = lba_doubly = lba_triply = lba_quadruply = 0;
	for (uint32_t i = 0; i < size_in_blocks; i++) {
		uint32_t this_block = marfs_get_free_lba_block();
		if (i != size_in_blocks - 1) {
			ata_write28(interface, this_block, data);
		} else if (size % 512) {
			uint8_t contents[512] = { 0 };
			for (uint16_t i = 0; i < size % 512; i++)
				contents[i] = data[i];
			ata_write28(interface, this_block, contents);
		}
		data += 512;
		marfs_mark_block_as_used(this_block);

		if (i > 9 + (128 * 128 * 128)) {
			if (!lba_quadruply) {
				lba_quadruply = marfs_get_free_lba_block();
				marfs_mark_block_as_used(lba_quadruply);
				inode->ext_4 = lba_quadruply;
			}
			marfs_update_recursive(4, i, lba_quadruply, this_block);
		} else if (i > 9 + (128 * 128)) {
			if (!lba_triply) {
				lba_triply = marfs_get_free_lba_block();
				marfs_mark_block_as_used(lba_triply);
				inode->ext_3 = lba_triply;
			}
			marfs_update_recursive(3, i, lba_triply, this_block);
		} else if (i > 9 + 128) {
			if (!lba_doubly) {
				lba_doubly = marfs_get_free_lba_block();
				marfs_mark_block_as_used(lba_doubly);
				inode->ext_2 = lba_doubly;
			}
			marfs_update_recursive(2, i, lba_doubly, this_block);
		} else if (i > 9) {
			if (!lba_singly) {
				lba_singly = marfs_get_free_lba_block();
				marfs_mark_block_as_used(lba_singly);
				inode->ext_1 = lba_singly;
			}
			marfs_update_recursive(1, i, lba_singly, this_block);
		} else {
			inode->DBPs[i] = this_block;
		}
	}

	// Write the inode
	uint32_t inode_lba = marfs_get_free_lba_inode();
	ata_write28(interface, inode_lba, (uint8_t *)inode);

	return inode_lba;
}