#!/usr/bin/env bash
# claudebox — trust-less, isolated Incus VMs with Claude Code, creds-free.
#   claudebox new --name <box> [--from <src>[/<snap>]] [--remote r] [--vm|--container]
#   claudebox list [--json]            — all your boxes
#   claudebox info <box>               — one box: state, IP, snapshot labels
#   claudebox shell|down|start|rm <box>
#   claudebox exec <box> -- <cmd...>
#   claudebox snapshot <box> [label]
#   claudebox restore <box> <snapshot>
# Boxes carry NO secrets: log into Claude interactively inside ('claude' then
# /login). Reuse an authenticated box via 'snapshot' + 'new --from'.
set -euo pipefail

root="$(cd "$(dirname "$(readlink -f "${BASH_SOURCE[0]}")")/.." && pwd)"
remote=""; mode="auto"; name=""; from=""; force=0; json=0
cmd="${1:-help}"; shift || true
args=()
while [ $# -gt 0 ]; do
  case "$1" in
    --name) name="$2"; shift 2 ;;
    --from) from="$2"; shift 2 ;;
    --remote) remote="$2:"; shift 2 ;;
    --vm) mode=vm; shift ;;
    --container) mode=container; shift ;;
    --force) force=1; shift ;;
    --json) json=1; shift ;;
    --) shift; args+=("$@"); break ;;
    *) args+=("$1"); shift ;;
  esac
done

die() { echo "claudebox: $*" >&2; exit 1; }
iname_of() { echo "$remote$1"; }   # instance name = box name; claudebox tags them with user.claudebox=1
need_name() {
  [ "${#args[@]}" -ge 1 ] && [ -n "${args[0]}" ] || die "usage: claudebox $cmd <box>"
}

pick_mode() {
  if [ "$mode" != auto ]; then echo "$mode"; return; fi
  if [ -n "$remote" ] || [ -e /dev/kvm ]; then echo vm; else
    echo "claudebox: no /dev/kvm — using container mode (weaker isolation, dev/test only)" >&2
    echo container
  fi
}

wait_agent() {
  local n="$1" i
  echo "claudebox: waiting for instance agent..."
  for i in $(seq 1 90); do
    if incus exec "$n" -- true >/dev/null 2>&1; then return; fi
    [ "$i" -eq 90 ] && die "instance agent never came up (incus console $n to inspect)"
    sleep 2
  done
}

new() {
  [ -n "$name" ] || die "usage: claudebox new --name <box> [--from <src>[/<snap>]]"
  local instance; instance="$(iname_of "$name")"
  if [ -n "$from" ]; then
    local src="${from%%/*}" snap="" srcref
    case "$from" in */*) snap="${from#*/}" ;; esac
    srcref="$(iname_of "$src")"; [ -n "$snap" ] && srcref="$srcref/$snap"
    incus copy "$srcref" "$instance"
    incus start "$instance"
    wait_agent "$instance"
    echo "claudebox: cloned $srcref — isolation and Claude auth carry over from the source."
  else
    local m extra=(); m="$(pick_mode)"
    # shellcheck disable=SC2054 # "root,size=60GiB" is a single incus argument
    if [ "$m" = vm ]; then extra+=(--vm --device root,size=60GiB); else extra+=(--config security.nesting=true); fi
    incus launch images:debian/13/cloud "$instance" --profile claude-dev \
      --config user.claudebox=1 \
      --config cloud-init.user-data="$(cat "$root/cloud-init/user-data.yaml")" \
      "${extra[@]}"
    wait_agent "$instance"
    echo "claudebox: waiting for phase-1 (cloud-init)..."
    incus exec "$instance" -- cloud-init status --wait
  fi
  echo "claudebox: ready — 'claudebox shell $name'. Log into Claude inside: run 'claude' then /login."
}

# Boxes are ordinary Incus instances tagged user.claudebox=1 — that tag is the
# only thing that makes them ours, so every read below is filtered by it and we
# never report on (or touch) an instance claudebox didn't mint.
# Emits: name,state,type,snapshot-count — none of which can contain a comma or a
# newline, so a plain -F, split is safe. (IPv4 can: a box running docker has
# several addresses and Incus quotes them across lines. It's fetched separately.)
boxes_csv() {
  incus list ${remote:+"$remote"} "user.claudebox=1" --format csv --columns nstS
}

box_ipv4() {   # first address only; strips Incus's " (iface)" suffix. "-" if none.
  incus list "$(iname_of "$1")" --format csv --columns 4 2>/dev/null \
    | tr -d '"' | sed 's/ (.*//' | grep -v '^[[:space:]]*$' | head -n1 \
    | grep . || echo "-"
}

# VIRTUAL-MACHINE is a mouthful in a table; anything unexpected passes through.
short_type() {
  case "$(printf '%s' "$1" | tr '[:upper:]' '[:lower:]')" in
    virtual-machine|virtualmachine) echo VM ;;
    container) echo CT ;;
    *) echo "$1" ;;
  esac
}

list_all() {
  local rows; rows="$(boxes_csv)"
  if [ -z "$rows" ]; then
    echo "claudebox: no boxes yet — create one with: claudebox new --name work" >&2
    return 0
  fi
  {
    echo "NAME,STATE,TYPE,SNAPSHOTS"
    while IFS=, read -r n s t snaps; do
      [ -n "$n" ] || continue
      echo "$n,${s:--},$(short_type "$t"),${snaps:-0}"
    done <<<"$rows"
  } | awk -F, '
    { for (i = 1; i <= NF; i++) { cell[NR, i] = $i; if (length($i) > w[i]) w[i] = length($i) } n = NR }
    END { for (r = 1; r <= n; r++) { line = ""
            for (i = 1; i <= 4; i++) line = line sprintf("%-*s  ", w[i], cell[r, i])
            sub(/ +$/, "", line); print line } }'
}

info() {
  local box="$1" row
  # Same tagged set as list_all: an untagged instance is not a box, it's someone
  # else's VM, and we say "no such box" rather than reaching into it.
  row="$(boxes_csv | awk -F, -v b="$box" '$1 == b { print; exit }')"
  [ -n "$row" ] || die "no such box: $box (see 'claudebox list')"

  local state type snaps
  IFS=, read -r _ state type snaps <<<"$row"
  printf '%-11s%s\n' NAME "$box" STATE "${state:--}" TYPE "$(short_type "$type")" \
    IPV4 "$(box_ipv4 "$box")"

  echo
  case "${snaps:-0}" in
    ''|0)
      echo "SNAPSHOTS  (none)"
      echo
      echo "Take one:   claudebox snapshot $box authed"
      return 0 ;;
  esac
  echo "SNAPSHOTS"
  local first=""
  while IFS=, read -r sname taken _; do
    [ -n "$sname" ] || continue
    [ -n "$first" ] || first="$sname"
    printf '  %-14s%s\n' "$sname" "$taken"
  done < <(incus snapshot list "$(iname_of "$box")" --format csv 2>/dev/null)
  echo
  echo "Clone one:  claudebox new --name <new> --from $box/${first:-<snapshot>}"
}

# 'list' lists them all; 'info' shows one. A box name handed to 'list' is a wrong
# guess we can answer, not a surprise: point at the command that does want one.
list() {
  if [ "${#args[@]}" -ge 1 ] && [ -n "${args[0]}" ]; then
    die "list takes no box — for one box, use: claudebox info ${args[0]}"
  fi
  if [ "$json" -eq 1 ]; then
    incus list ${remote:+"$remote"} "user.claudebox=1" --format json
  else
    list_all
  fi
}

case "$cmd" in
  new)      new ;;
  snapshot) need_name; label="${args[1]:-manual-$(date +%s)}"; incus snapshot create "$(iname_of "${args[0]}")" "$label"; echo "$label" ;;
  restore)  need_name; [ -n "${args[1]:-}" ] || die "usage: claudebox restore <box> <snapshot>"; incus restore "$(iname_of "${args[0]}")" "${args[1]}" ;;
  shell)    need_name; incus exec "$(iname_of "${args[0]}")" -- sudo -u claude -i ;;
  exec)     need_name; incus exec "$(iname_of "${args[0]}")" -- sudo -u claude -i "${args[@]:1}" ;;
  down)     need_name; incus stop "$(iname_of "${args[0]}")" ;;
  start)    need_name; incus start "$(iname_of "${args[0]}")" ;;
  rm)       need_name; incus delete -f "$(iname_of "${args[0]}")"; echo "claudebox: removed $(iname_of "${args[0]}")" ;;
  list)     list ;;
  info)     need_name
            if [ "$json" -eq 1 ]; then incus list "$(iname_of "${args[0]}")" --format json; else info "${args[0]}"; fi ;;
  status)   echo "claudebox: 'status' is deprecated — use 'claudebox list'." >&2; list_all ;;
  help|*)   sed -n '2,11p' "$0" | sed 's/^# \{0,1\}//' ;;
esac