#!/usr/bin/env python3
"""
homelab — single-binary CLI for managing the hubris homelab from any client.

Reads /opt/homelab-context/inventory.yaml as the source of truth, resolves
hostnames to mesh addresses, and wraps the common ops (ssh, pct, logs, restart,
status, open, secret, client add/remove, sync, mcp).

Mutating subcommands prompt unless -y / --yes is passed.

Run `homelab --help` or `homelab <subcommand> --help` for usage.
"""

from __future__ import annotations

import argparse
import json
import os
import shutil
import subprocess
import sys
import urllib.request
from pathlib import Path

try:
    import yaml
except ImportError:
    print("PyYAML required (apt install python3-yaml or pip install pyyaml)", file=sys.stderr)
    sys.exit(2)

CONTEXT = Path(os.environ.get("HOMELAB_CONTEXT_DIR", "/opt/homelab-context"))
INVENTORY = CONTEXT / "inventory.yaml"
HOSTS_DIR = CONTEXT / "hosts"
AGE_KEY = Path(os.environ.get("SOPS_AGE_KEY_FILE", "/etc/age/key.txt"))


# ---------- helpers ----------

def die(msg: str, code: int = 1) -> None:
    print(f"homelab: {msg}", file=sys.stderr)
    sys.exit(code)


def inventory() -> dict:
    if not INVENTORY.exists():
        die(f"no inventory at {INVENTORY} — has bootstrap run?")
    return yaml.safe_load(INVENTORY.read_text())


def host(name: str) -> dict:
    inv = inventory()
    if name not in inv.get("hosts", {}):
        die(f"unknown host: {name}")
    return inv["hosts"][name]


def host_address(name: str, prefer_lan: bool = False) -> str:
    h = host(name)
    mesh = h.get("mesh", {})
    candidates = []
    if prefer_lan and h.get("lan_ip"):
        candidates.append(h["lan_ip"])
    candidates.extend([
        mesh.get("netbird", {}).get("fqdn") if isinstance(mesh.get("netbird"), dict) else None,
        mesh.get("netbird", {}).get("ip") if isinstance(mesh.get("netbird"), dict) else None,
        h.get("lan_ip"),
        mesh.get("tailscale", {}).get("fqdn") if isinstance(mesh.get("tailscale"), dict) else None,
        mesh.get("tailscale", {}).get("ip") if isinstance(mesh.get("tailscale"), dict) else None,
    ])
    for c in candidates:
        if c:
            return c
    die(f"no reachable address for host {name}")


def hubris_ssh() -> list[str]:
    """SSH base command for hubris, honoring its non-default Netbird SSH port."""
    h = host("hubris")
    port = h.get("ssh", {}).get("netbird_port", 22)
    return ["ssh", "-p", str(port), f"root@{host_address('hubris')}"]


def confirm(question: str, default_no: bool = True) -> bool:
    suffix = "[y/N]" if default_no else "[Y/n]"
    try:
        answer = input(f"{question} {suffix} ").strip().lower()
    except (EOFError, KeyboardInterrupt):
        return False
    if not answer:
        return not default_no
    return answer in ("y", "yes")


def service(name: str) -> dict:
    inv = inventory()
    svc = inv.get("services", {}).get(name)
    if not svc:
        die(f"unknown service: {name}")
    return svc


def service_backend_host(name: str) -> str:
    return service(name)["backend"]


def push_inventory(message: str) -> None:
    """Stage + commit + push inventory + regenerated hosts/."""
    subprocess.run(["python3", str(CONTEXT / "mcp" / "build_host_files.py")],
                   check=True, cwd=CONTEXT)
    subprocess.run(["git", "add", "inventory.yaml", "hosts/"], check=True, cwd=CONTEXT)
    if subprocess.run(["git", "diff", "--cached", "--quiet"], cwd=CONTEXT).returncode == 0:
        print("(no changes to commit)")
        return
    subprocess.run(["git", "commit", "-m", message], check=True, cwd=CONTEXT)
    subprocess.run(["git", "push"], check=True, cwd=CONTEXT)


# ---------- subcommands ----------

def cmd_whoami(args: argparse.Namespace) -> int:
    name = args.hostname or os.uname().nodename.split(".")[0]
    path = HOSTS_DIR / f"{name}.yaml"
    if not path.exists():
        die(f"no hosts/{name}.yaml — has this client been enrolled?")
    print(path.read_text())
    return 0


def cmd_list(args: argparse.Namespace) -> int:
    inv = inventory()
    print(f"{'NAME':<22} {'KIND':<14} {'OS':<6} {'ROLE':<22} ADDRESS")
    for name, entry in inv.get("hosts", {}).items():
        addr = ""
        try:
            addr = host_address(name)
        except SystemExit:
            addr = "?"
        print(f"{name:<22} {entry.get('kind','?'):<14} {entry.get('os','?'):<6} "
              f"{entry.get('role','?'):<22} {addr}")
    print()
    print("Services:")
    for svc, entry in inv.get("services", {}).items():
        url = entry.get("url") or entry.get("endpoint") or ""
        backend = entry.get("backend", "?")
        print(f"  {svc:<22} backend={backend:<15} {url}")
    return 0


def cmd_ssh(args: argparse.Namespace) -> int:
    name = args.host
    h = host(name)
    addr = host_address(name)
    cmd = ["ssh"]
    # hubris uses a non-default Netbird SSH port for the mesh path
    if name == "hubris":
        port = h.get("ssh", {}).get("netbird_port", 22)
        cmd.extend(["-p", str(port)])
    user = args.user or "root"
    cmd.append(f"{user}@{addr}")
    if args.command:
        cmd.append(" ".join(args.command))
    os.execvp(cmd[0], cmd)


def cmd_pct(args: argparse.Namespace) -> int:
    lxc = args.lxc
    inv = inventory()
    entry = inv.get("hosts", {}).get(lxc)
    if not entry or entry.get("kind") != "lxc":
        die(f"{lxc} is not an LXC in inventory")
    pve_id = str(entry["pve_id"])
    action = args.action
    if action == "exec":
        if not args.rest:
            die("pct exec needs a command")
        remote_cmd = ["pct", "exec", pve_id, "--"] + args.rest
    elif action in ("status", "config", "start", "stop", "reboot", "shutdown"):
        remote_cmd = ["pct", action, pve_id]
    elif action == "enter":
        remote_cmd = ["pct", "enter", pve_id]
    else:
        die(f"unknown pct action: {action}")
    if action in ("stop", "reboot", "shutdown") and not args.yes:
        if not confirm(f"run 'pct {action} {pve_id}' (={lxc}) on hubris?"):
            return 1
    cmd = hubris_ssh() + ["--"] + remote_cmd
    return subprocess.call(cmd)


def cmd_logs(args: argparse.Namespace) -> int:
    svc = args.service
    host_name = service_backend_host(svc)
    unit = service(svc).get("systemd_unit", svc)
    if host_name == "hubris":
        base = hubris_ssh()
    else:
        base = ["ssh", f"root@{host_address(host_name)}"]
    remote = ["journalctl", "-u", unit, "-n", str(args.lines), "--no-pager"]
    if args.follow:
        remote.append("-f")
    return subprocess.call(base + ["--"] + remote)


def cmd_restart(args: argparse.Namespace) -> int:
    svc = args.service
    host_name = service_backend_host(svc)
    unit = service(svc).get("systemd_unit", svc)
    if not args.yes:
        if not confirm(f"restart systemd unit '{unit}' on {host_name}?"):
            return 1
    if host_name == "hubris":
        base = hubris_ssh()
    else:
        base = ["ssh", f"root@{host_address(host_name)}"]
    return subprocess.call(base + ["--", "systemctl", "restart", unit])


def cmd_open(args: argparse.Namespace) -> int:
    url = service(args.service).get("url")
    if not url:
        die(f"service {args.service} has no url in inventory")
    opener = "open" if sys.platform == "darwin" else "xdg-open"
    if shutil.which(opener) is None:
        print(url)
        return 0
    return subprocess.call([opener, url])


def cmd_status(args: argparse.Namespace) -> int:
    inv = inventory()
    print(f"{'NAME':<22} REACH")
    for name, entry in inv.get("hosts", {}).items():
        try:
            addr = host_address(name)
        except SystemExit:
            print(f"{name:<22} no-address")
            continue
        # Quick ping-ish check via mesh.
        proc = subprocess.run(
            ["ping", "-c", "1", "-W", "2", addr],
            capture_output=True, text=True,
        )
        reach = "ok" if proc.returncode == 0 else "down"
        print(f"{name:<22} {reach:<5} {addr}")
    print()
    print(f"{'SERVICE':<22} URL HEALTH")
    for svc, entry in inv.get("services", {}).items():
        url = entry.get("url") or entry.get("endpoint")
        if not url:
            continue
        proc = subprocess.run(
            ["curl", "-sS", "-o", "/dev/null", "-w", "%{http_code}",
             "--max-time", "3", url],
            capture_output=True, text=True,
        )
        code = proc.stdout.strip() or "---"
        print(f"{svc:<22} {url:<50} {code}")
    return 0


def cmd_secret(args: argparse.Namespace) -> int:
    name = args.name
    path = CONTEXT / "secrets" / f"{name}.yaml"
    if not path.exists():
        die(f"no secret '{name}' (looked for {path})")
    if not AGE_KEY.exists():
        die(f"no age key at {AGE_KEY} — has bootstrap run?")
    env = {**os.environ, "SOPS_AGE_KEY_FILE": str(AGE_KEY)}
    return subprocess.call(["sops", "-d", str(path)], env=env)


def cmd_sync(args: argparse.Namespace) -> int:
    if sys.platform == "darwin":
        return subprocess.call(
            ["sudo", "launchctl", "kickstart", "-k",
             "system/network.hubris.homelab-context-sync"]
        )
    return subprocess.call(
        ["sudo", "systemctl", "start", "homelab-context-sync.service"]
    )


def cmd_mcp(args: argparse.Namespace) -> int:
    svc = service("homelab_mcp")
    endpoint = svc.get("endpoint")
    if not endpoint:
        die("no MCP endpoint in inventory")
    # Minimal SSE invocation via mcp-cli if available; otherwise instruct.
    if shutil.which("mcp"):
        return subprocess.call(["mcp", "call", endpoint, args.tool, *(args.args or [])])
    die("'mcp' CLI not installed. Install with: pip install 'mcp[cli]'")


def cmd_client_add(args: argparse.Namespace) -> int:
    name = args.name
    inv = inventory()
    if not args.finalize_pubkey:
        if name in inv["hosts"]:
            die(f"{name} already in inventory (use --finalize-pubkey to update age_pubkey)")
        print(f"Adding new client '{name}' to inventory.yaml.")
        kind = input("  kind [workstation/lxc/vm] (default: workstation): ").strip() or "workstation"
        os_name = input(f"  os [linux/macos] (default: linux): ").strip() or "linux"
        netbird_fqdn = input(f"  netbird FQDN (default: {name}.netbird.selfhosted): ").strip() \
            or f"{name}.netbird.selfhosted"
        role = input("  role (e.g. primary-dev, dev): ").strip() or "dev"
        entry = {
            "kind": kind,
            "os": os_name,
            "role": role,
            "mesh": {"netbird": {"fqdn": netbird_fqdn}},
            "age_pubkey": "",
        }
        inv["hosts"][name] = entry
        INVENTORY.write_text(yaml.safe_dump(inv, sort_keys=False))
        push_inventory(f"client-add: {name}")
        print()
        print("Next steps:")
        print(f"  1. Join {name} to Netbird (out-of-band, Netbird console / setup key).")
        print(f"  2. On {name}: curl -fsSL <gitea>/dtoro/Homelab-Docs/raw/main/bootstrap.sh | sudo bash")
        print(f"  3. bootstrap prints an age pubkey — bring it back here and run:")
        print(f"     homelab client add {name} --finalize-pubkey <age1...>")
        return 0

    # finalize_pubkey path
    if name not in inv["hosts"]:
        die(f"{name} not in inventory — run 'homelab client add {name}' first (no --finalize-pubkey)")
    inv["hosts"][name]["age_pubkey"] = args.finalize_pubkey
    INVENTORY.write_text(yaml.safe_dump(inv, sort_keys=False))
    push_inventory(f"client-add: {name} (finalize age_pubkey)")
    print(f"finalized age_pubkey for {name}.")
    return 0


def cmd_client_remove(args: argparse.Namespace) -> int:
    name = args.name
    inv = inventory()
    if name not in inv["hosts"]:
        die(f"{name} not in inventory")
    if not args.yes:
        print(f"This will:")
        print(f"  1. Remove {name} from inventory.yaml and hosts/")
        print(f"  2. Re-encrypt every secret without {name} as recipient")
        print(f"  3. Revoke {name}'s age key on the issuance server (shred + denylist)")
        print(f"  4. Commit + push the change")
        print(f"After: rotate any credentials inside secrets {name} previously had access to,")
        print(f"       and revoke {name}'s Netbird peer in the console.")
        if not confirm(f"proceed removing {name}?"):
            return 1

    # 1. Inventory
    del inv["hosts"][name]
    INVENTORY.write_text(yaml.safe_dump(inv, sort_keys=False))

    # 2. SOPS — remove recipient. Requires `sops updatekeys` after we edit .sops.yaml.
    # We don't try to programmatically edit .sops.yaml because the recipient list
    # there is keyed by path-glob rules; the operator must remove the pubkey line
    # if it's listed by-name. We'll trigger updatekeys after the operator confirms.
    secrets_dir = CONTEXT / "secrets"
    if secrets_dir.exists():
        print()
        print("[remove] re-encrypting secrets without removed recipient (sops updatekeys)")
        sops_yaml = CONTEXT / ".sops.yaml"
        if sops_yaml.exists():
            print(f"  Note: review {sops_yaml} for hard-coded recipients of '{name}' "
                  "and remove them before sops updatekeys.")
        for f in sorted(secrets_dir.glob("*.yaml")):
            subprocess.run(["sops", "updatekeys", "-y", str(f)], check=False)

    # 3. Revoke on issuance server
    admin_token_url = inv["services"].get("secrets_issuance", {}).get("endpoint", "").replace("/issue", "")
    if admin_token_url:
        revoke_url = admin_token_url.rstrip("/") + "/revoke"
        token = os.environ.get("HOMELAB_ISSUANCE_ADMIN_TOKEN", "")
        if not token:
            print(f"  WARNING: set HOMELAB_ISSUANCE_ADMIN_TOKEN to call {revoke_url} — skipping revocation")
        else:
            req = urllib.request.Request(
                revoke_url, data=json.dumps({"hostname": name}).encode(),
                headers={"X-Admin-Token": token, "Content-Type": "application/json"},
                method="POST",
            )
            try:
                with urllib.request.urlopen(req, timeout=10) as resp:
                    print(f"  issuance revoke: {resp.status} {resp.read().decode().strip()}")
            except Exception as e:
                print(f"  issuance revoke failed: {e}")

    # 4. Commit + push
    push_inventory(f"client-remove: {name}")

    print()
    print("Follow-up checklist (the CLI cannot do these automatically):")
    print(f"  [ ] Revoke {name}'s Netbird peer in the Netbird console.")
    print(f"  [ ] Rotate any credentials whose ciphertext {name} already has on disk")
    print(f"      — the only real revocation for past-disclosed secrets is rotation.")
    print(f"  [ ] If the machine is reachable and decommissioned, run:")
    print(f"        homelab nuke {name}    (shreds /etc/age/key.txt, removes /opt/homelab-context)")
    return 0


def cmd_nuke(args: argparse.Namespace) -> int:
    name = args.name
    if not args.yes:
        if not confirm(f"destroy /etc/age/key.txt + /opt/homelab-context on {name}?"):
            return 1
    addr = host_address(name)
    remote = ("set -euo pipefail; "
              "shred -u /etc/age/key.txt 2>/dev/null || true; "
              "rm -rf /opt/homelab-context; "
              "systemctl disable --now homelab-context-sync.timer 2>/dev/null || true; "
              "launchctl bootout system/network.hubris.homelab-context-sync 2>/dev/null || true; "
              "echo nuked")
    return subprocess.call(["ssh", f"root@{addr}", remote])


# ---------- argparse ----------

def main() -> int:
    p = argparse.ArgumentParser(prog="homelab", description=__doc__)
    sub = p.add_subparsers(dest="cmd", required=True)

    sp = sub.add_parser("whoami", help="print this host's hosts/<hostname>.yaml")
    sp.add_argument("hostname", nargs="?")
    sp.set_defaults(func=cmd_whoami)

    sp = sub.add_parser("list", help="list hosts and services from inventory")
    sp.set_defaults(func=cmd_list)

    sp = sub.add_parser("ssh", help="ssh to a host via mesh")
    sp.add_argument("host")
    sp.add_argument("--user", "-u", default=None)
    sp.add_argument("command", nargs=argparse.REMAINDER)
    sp.set_defaults(func=cmd_ssh)

    sp = sub.add_parser("pct", help="proxy pct commands via ssh to hubris")
    sp.add_argument("lxc")
    sp.add_argument("action")
    sp.add_argument("rest", nargs=argparse.REMAINDER)
    sp.add_argument("--yes", "-y", action="store_true")
    sp.set_defaults(func=cmd_pct)

    sp = sub.add_parser("logs", help="journalctl for a service")
    sp.add_argument("service")
    sp.add_argument("--lines", "-n", type=int, default=200)
    sp.add_argument("--follow", "-f", action="store_true")
    sp.set_defaults(func=cmd_logs)

    sp = sub.add_parser("restart", help="restart a service")
    sp.add_argument("service")
    sp.add_argument("--yes", "-y", action="store_true")
    sp.set_defaults(func=cmd_restart)

    sp = sub.add_parser("open", help="open a service's URL in browser")
    sp.add_argument("service")
    sp.set_defaults(func=cmd_open)

    sp = sub.add_parser("status", help="ping every host + HTTP-check every service")
    sp.set_defaults(func=cmd_status)

    sp = sub.add_parser("secret", help="decrypt a secret (sops -d wrapper)")
    sp.add_argument("name")
    sp.set_defaults(func=cmd_secret)

    sp = sub.add_parser("sync", help="manually trigger homelab-context-sync")
    sp.set_defaults(func=cmd_sync)

    sp = sub.add_parser("mcp", help="call an MCP tool (requires 'mcp' CLI installed)")
    sp.add_argument("tool")
    sp.add_argument("args", nargs=argparse.REMAINDER)
    sp.set_defaults(func=cmd_mcp)

    sp = sub.add_parser("nuke", help="shred /etc/age/key.txt + /opt/homelab-context on a host")
    sp.add_argument("name")
    sp.add_argument("--yes", "-y", action="store_true")
    sp.set_defaults(func=cmd_nuke)

    client = sub.add_parser("client", help="client lifecycle (add/remove)")
    csub = client.add_subparsers(dest="action", required=True)
    csub_add = csub.add_parser("add")
    csub_add.add_argument("name")
    csub_add.add_argument("--finalize-pubkey", default=None,
                          help="set/update age_pubkey for an already-added client")
    csub_add.set_defaults(func=cmd_client_add)
    csub_rm = csub.add_parser("remove")
    csub_rm.add_argument("name")
    csub_rm.add_argument("--yes", "-y", action="store_true")
    csub_rm.set_defaults(func=cmd_client_remove)

    args = p.parse_args()
    return args.func(args)


if __name__ == "__main__":
    sys.exit(main())