"""Fixer for 'import exceptions'.

exceptions.X -> X"""

# Local imports
from lib2to3 import fixer_base
from lib2to3.pytree import Leaf
from lib2to3.fixes.fix_imports import FixImports


class FixImportExceptions(FixImports):
    mapping = {'exceptions': None}

    def transform(self, node, results):
        import_mod = results.get("module_name")
        if import_mod:
            mod_name = import_mod.value
            new_name = self.mapping[mod_name]
            if "multiple_imports" in results:
                results = self.match(node)
                if results:
                    self.transform(node, results)
            else:
                node.remove()
        else:
            # Replace usage of the module.
            to_remove = []
            for (i, child) in enumerate(node.children):
                if isinstance(child, Leaf) and child.value in self.mapping:
                    to_remove.append(i)
            for i in reversed(to_remove):
                assert node.children[i+1].children[0].value == '.'
                del node.children[i+1].children[0] # delete the dot
                del node.children[i] # delete the module