#!/usr/bin/python3

import btrfs
import sys

load_data_refs = True
load_metadata_refs = True

if len(sys.argv) < 3:
    print("Usage: {} <vaddr> <mountpoint>".format(sys.argv[0]))
    sys.exit(1)

vaddr = int(sys.argv[1])
with btrfs.FileSystem(sys.argv[2]) as fs:
    block_group = fs.block_group(vaddr)
    print(block_group)
    for extent in fs.extents(vaddr, vaddr + block_group.length - 1,
                             load_data_refs, load_metadata_refs):
        print(extent)
        if isinstance(extent, btrfs.ctree.ExtentItem):
            if extent.flags & btrfs.ctree.EXTENT_FLAG_DATA and load_data_refs:
                for data_ref in extent.extent_data_refs:
                    print("    " + str(data_ref))
                for shared_ref in extent.shared_data_refs:
                    print("    " + str(shared_ref))
            elif extent.flags & btrfs.ctree.EXTENT_FLAG_TREE_BLOCK and load_metadata_refs:
                print("    " + str(extent.tree_block_info))
                for tree_block_backref in extent.tree_block_refs:
                    print("    " + str(tree_block_backref))
                for shared_block_backref in extent.shared_block_refs:
                    print("    " + str(shared_block_backref))
        elif isinstance(extent, btrfs.ctree.MetaDataItem) and load_metadata_refs:
            for tree_block_backref in extent.tree_block_refs:
                print("    " + str(tree_block_backref))
            for shared_block_backref in extent.shared_block_refs:
                print("    " + str(shared_block_backref))