"""
`devices`: this account's devices on the node serving a group — what the
application's "Your devices on this node" shows and does.

Identities are per node, so a group names the node. `approve` admits the device
showing a code; `revoke` retires one, asked first (`--yes` for a script). A node
where this machine is the only linked device admits no other without this.
"""

import json
import sys

from ..client import devices
from ..client.groups import my_groups, open_group
from ..client.paths import group_arg, handle, resolve_group
from ..errors import REFUSED, USAGE, CliError
from ..output import confirm, err, safe, sentence
from .context import Context

HELP = "your devices on the node serving a group: list, approve a new one, revoke one"


def add_parser(sub, parent) -> None:
    p = sub.add_parser("devices", parents=[parent], help=HELP, description=sentence(HELP)
                       + ". A new device shows a code; approve it here, from a machine "
                         "already linked to that node.")
    p.add_argument("verb", choices=("list", "approve", "revoke"))
    p.add_argument("group", metavar="GROUP", help="the group, as `groups` lists it")
    p.add_argument("arg", nargs="?", metavar="CODE|DEVICE",
                   help="approve: the code the new device shows; revoke: the device, by "
                        "the first characters of its key as `devices list` shows it")
    p.add_argument("-y", "--yes", action="store_true",
                   help="revoke without asking for confirmation")


def _when(iso: str) -> str:
    return (iso or "")[:16].replace("T", " ")


async def run(ctx: Context) -> int:
    a = ctx.args
    if a.verb != "list" and not a.arg:
        raise CliError(USAGE, f"Name the {'code' if a.verb == 'approve' else 'device'}: "
                              f"meshbay-cli devices {a.verb} GROUP "
                              f"{'CODE' if a.verb == 'approve' else 'DEVICE'}")
    await ctx.hub.check_version()
    account = ctx.account()
    session = None
    try:
        group = resolve_group(await my_groups(account), group_arg(a.group))
        name = handle(group)
        session = await open_group(account, group)
        if a.verb == "list":
            return _print(ctx, name, await devices.list_devices(session))
        if a.verb == "approve":
            pk = await devices.approve(session, account, a.arg)
            print(json.dumps({"approved": pk}) if a.json else
                  f"Approved the device {pk[:16]} on the node serving {safe(name)}.")
            return 0
        device = devices.find_device((await devices.list_devices(session))["devices"],
                                     a.arg)
        if device.get("is_this_one"):
            raise CliError(REFUSED, "That is this machine. Revoke it from another of your "
                                    "devices.")
        label = device.get("label") or "no label"
        confirm(f"Revoke the device {device['pk_ed25519'][:16]} ({safe(label)}) on the "
                f"node serving {safe(name)}? It will no longer open this node's groups.",
                a.yes)
        await devices.revoke(session, account, device["pk_ed25519"])
        print(json.dumps({"revoked": device["pk_ed25519"]}) if a.json else
              f"Revoked the device {device['pk_ed25519'][:16]}.")
        return 0
    finally:
        if session is not None:
            await session.close()
        await account.close()


def _print(ctx: Context, name: str, listed: dict) -> int:
    rows = listed["devices"]
    if ctx.args.json:
        json.dump(listed, sys.stdout, indent=1)
        print()
        return 0
    print(f"  {'KEY':<18}{'ADDED':<18}{'VIA':<12}LABEL")
    for d in rows:
        mark = "*" if d.get("is_this_one") else " "
        print(f"{mark} {d['pk_ed25519'][:16]:<18}{_when(d.get('pinned_at')):<18}"
              f"{safe(d.get('pinned_via') or ''):<12}{safe(d.get('label') or '')}")
    if not ctx.args.quiet:
        err("* this machine")
        if listed["pending"]:
            n = listed["pending"]
            err(f"{n} device{'s' if n != 1 else ''} waiting for approval: "
                f"meshbay-cli devices approve {name} CODE")
    return 0