"""
The ssh client wrapper system contains the routines that are used to alter
how executions are run in the salt-ssh system, this allows for state routines
to be easily rewritten to execute in a way that makes them do the same tasks
as ZeroMQ salt, but via ssh.
"""


import copy

import salt.client.ssh
import salt.loader
import salt.utils.data
import salt.utils.json


class FunctionWrapper:
    """
    Create an object that acts like the salt function dict and makes function
    calls remotely via the SSH shell system
    """

    def __init__(
        self,
        opts,
        id_,
        host,
        wfuncs=None,
        mods=None,
        fsclient=None,
        cmd_prefix=None,
        aliases=None,
        minion_opts=None,
        **kwargs
    ):
        super().__init__()
        self.cmd_prefix = cmd_prefix
        self.wfuncs = wfuncs if isinstance(wfuncs, dict) else {}
        self.opts = opts
        self.mods = mods if isinstance(mods, dict) else {}
        self.kwargs = {"id_": id_, "host": host}
        self.fsclient = fsclient
        self.kwargs.update(kwargs)
        self.aliases = aliases
        if self.aliases is None:
            self.aliases = {}
        self.minion_opts = minion_opts

    def __contains__(self, key):
        """
        We need to implement a __contains__ method, othwerwise when someone
        does a contains comparison python assumes this is a sequence, and does
        __getitem__ keys 0 and up until IndexError
        """
        try:
            self[key]  # pylint: disable=W0104
            return True
        except KeyError:
            return False

    def __getitem__(self, cmd):
        """
        Return the function call to simulate the salt local lookup system
        """
        if "." not in cmd and not self.cmd_prefix:
            # Form of salt.cmd.run in Jinja -- it's expecting a subdictionary
            # containing only 'cmd' module calls, in that case. Create a new
            # FunctionWrapper which contains the prefix 'cmd' (again, for the
            # salt.cmd.run example)
            kwargs = copy.deepcopy(self.kwargs)
            id_ = kwargs.pop("id_")
            host = kwargs.pop("host")
            return FunctionWrapper(
                self.opts,
                id_,
                host,
                wfuncs=self.wfuncs,
                mods=self.mods,
                fsclient=self.fsclient,
                cmd_prefix=cmd,
                aliases=self.aliases,
                minion_opts=self.minion_opts,
                **kwargs
            )

        if self.cmd_prefix:
            # We're in an inner FunctionWrapper as created by the code block
            # above. Reconstruct the original cmd in the form 'cmd.run' and
            # then evaluate as normal
            cmd = "{}.{}".format(self.cmd_prefix, cmd)

        if cmd in self.wfuncs:
            return self.wfuncs[cmd]

        if cmd in self.aliases:
            return self.aliases[cmd]

        def caller(*args, **kwargs):
            """
            The remote execution function
            """
            argv = [cmd]
            argv.extend([salt.utils.json.dumps(arg) for arg in args])
            argv.extend(
                [
                    "{}={}".format(
                        salt.utils.stringutils.to_str(key), salt.utils.json.dumps(val)
                    )
                    for key, val in kwargs.items()
                ]
            )
            single = salt.client.ssh.Single(
                self.opts,
                argv,
                mods=self.mods,
                disable_wipe=True,
                fsclient=self.fsclient,
                minion_opts=self.minion_opts,
                **self.kwargs
            )
            stdout, stderr, retcode = single.cmd_block()
            if stderr.count("Permission Denied"):
                return {
                    "_error": "Permission Denied",
                    "stdout": stdout,
                    "stderr": stderr,
                    "retcode": retcode,
                }
            try:
                ret = salt.utils.json.loads(stdout)
                if len(ret) < 2 and "local" in ret:
                    ret = ret["local"]
                ret = ret.get("return", {})
            except ValueError:
                ret = {
                    "_error": "Failed to return clean data",
                    "stderr": stderr,
                    "stdout": stdout,
                    "retcode": retcode,
                }
            return ret

        return caller

    def __setitem__(self, cmd, value):
        """
        Set aliases for functions
        """
        if "." not in cmd and not self.cmd_prefix:
            # Form of salt.cmd.run in Jinja -- it's expecting a subdictionary
            # containing only 'cmd' module calls, in that case. We don't
            # support assigning directly to prefixes in this way
            raise KeyError(
                "Cannot assign to module key {} in the FunctionWrapper".format(cmd)
            )

        if self.cmd_prefix:
            # We're in an inner FunctionWrapper as created by the first code
            # block in __getitem__. Reconstruct the original cmd in the form
            # 'cmd.run' and then evaluate as normal
            cmd = "{}.{}".format(self.cmd_prefix, cmd)

        if cmd in self.wfuncs:
            self.wfuncs[cmd] = value

        # Here was assume `value` is a `caller` function from __getitem__.
        # We save it as an alias and then can return it when referenced
        # later in __getitem__
        self.aliases[cmd] = value

    def get(self, cmd, default):
        """
        Mirrors behavior of dict.get
        """
        if cmd in self:
            return self[cmd]
        else:
            return default
