uint32_t pstorage_clear_block(pstorage_handle_t * storage_handle, uint16_t size){
    static uint8_t page_swap[PAGE_SIZE];
    if((storage_handle->block_id % PAGE_SIZE) == 0) // this is a page start
        if(size == PAGE_SIZE) // this block fits the whole page
            return pstorage_clear(storage_handle, PAGE_SIZE);


    uint32_t retval, page_start, page_end, page, offset, storage_addr = storage_handle->block_id;
        page_start =  (storage_addr / PSTORAGE_FLASH_PAGE_SIZE);
    page_end =  ((storage_addr + size) / PSTORAGE_FLASH_PAGE_SIZE);
    for(page = page_start; page <= page_end; page++){
        storage_handle->block_id = page * PAGE_SIZE;
        // get page
        memcpy(page_swap, (uint32_t *)(page * PSTORAGE_FLASH_PAGE_SIZE), PSTORAGE_FLASH_PAGE_SIZE);
        // first page
        if(page == page_start){
            offset = (storage_addr - (page * PSTORAGE_FLASH_PAGE_SIZE)); // distance from page start
            if((size + offset) > PSTORAGE_FLASH_PAGE_SIZE){ // if it goes to another page, delete from this page to the end
            memset(page_swap + offset, 0xFF, PSTORAGE_FLASH_PAGE_SIZE - offset);
            }
            else // if not, delete from offset to size
                memset(page_swap + offset, 0xFF, size);
        } else if(page == page_end){ // second page
            memset(page_swap, 0xFF, size - (PSTORAGE_FLASH_PAGE_SIZE - offset)); // delete the remaining size
        }

        pstorage_clear(storage_handle, PAGE_SIZE);

        retval = pstorage_store(storage_handle,
        (uint8_t *) page_swap,
        PAGE_SIZE,
        0);
    }
    return retval;
}