import gdb
from teachos import TeachOSBasePrinter


class KstdUniquePtrPrinter(TeachOSBasePrinter):
    def __init__(self, val):
        super().__init__(val)
        self.__type = val.type.template_argument(0)

    def to_string(self):
        pointer = self.value["pointer"]
        if int(pointer) == 0:
            return f"kstd::unique_ptr<{self.__type}> (empty)"
        return f"kstd::unique_ptr<{self.__type}>"

    def children(self):
        pointer = self.value["pointer"]
        if int(pointer) != 0:
            yield ("get()", pointer.dereference())

        yield from super().children()


class KstdSharedPtrPrinter(TeachOSBasePrinter):
    def __init__(self, val):
        super().__init__(val)
        self.__type = val.type.template_argument(0)

    def to_string(self):
        pointer = self.value["pointer"]
        control_block = self.value["control"]

        if int(pointer) == 0 or int(control_block) == 0:
            return f"shared_ptr<{self.__type}> (empty)"

        strong_refs = int(control_block["shared_count"]["_M_i"])
        weak_refs = int(control_block["weak_count"]["_M_i"])

        return (
            f"shared_ptr<{self.__type}> use count {strong_refs}, weak count {weak_refs}"
        )

    def children(self):
        pointer = self.value["pointer"]
        control_block = self.value["control"]

        if int(pointer) != 0:
            yield ("get()", pointer.dereference())

        yield from super().children()