#!/usr/bin/env bash
set -Eeuo pipefail

# -------------------------
# Logging helpers (stderr!)
# -------------------------
_is_tty() { [[ -t 2 ]]; }
_ts() { date '+%F %T'; }

log()  { echo "[$(_ts)] $*" >&2; }
info() { log "INFO: $*"; }
warn() { log "WARN: $*"; }
die()  { log "ERROR: $*"; exit 1; }

need_cmd() {
  local c
  for c in "$@"; do
    command -v "$c" >/dev/null 2>&1 || die "Missing command: $c"
  done
}

on_error() {
  local lineno="$1" cmd="$2" code="$3"
  die "Failed at line ${lineno}: ${cmd} (exit=${code})"
}

setup_traps() {
  trap 'on_error "${LINENO}" "${BASH_COMMAND}" "$?"' ERR
}

# -------------------------
# Proxmox helpers
# -------------------------
pve_storage_exists() {
  local st="$1"
  pvesm status --storage "$st" >/dev/null 2>&1
}

pve_bridge_exists() {
  local br="$1"
  [[ -d "/sys/class/net/${br}/bridge" ]]
}

# Return a list of all VMIDs in the cluster (VM + CT)
# Output: one vmid per line (stdout only)
pve_cluster_vmids() {
  need_cmd pvesh python3
  pvesh get /cluster/resources --type vm --output-format json \
  | python3 - <<'PY'
import json,sys
data=json.load(sys.stdin)
ids=sorted({int(x["vmid"]) for x in data if "vmid" in x})
for i in ids:
    print(i)
PY
}

# Pick a free CTID cluster-wide. Default start=2000 to avoid collisions with "classic" ranges.
pve_next_free_ctid() {
  need_cmd python3
  local start="${1:-2000}"
  local end="${2:-9999}"

  local used
  used="$(pve_cluster_vmids || true)"

  python3 - <<PY
used=set()
for line in """$used""".splitlines():
    line=line.strip()
    if not line: 
        continue
    try:
        used.add(int(line))
    except:
        pass

start=int("$start"); end=int("$end")
for vmid in range(start, end+1):
    if vmid not in used:
        print(vmid)
        raise SystemExit(0)
raise SystemExit(1)
PY
}

# Ensure Debian 12 CT template is available.
# Returns template ref like: local:vztmpl/debian-12-standard_12.12-1_amd64.tar.zst (stdout only)
pve_template_ensure_debian12() {
  need_cmd pveam awk grep

  local store="$1"
  local tpl="debian-12-standard_12.12-1_amd64.tar.zst"

  # pveam templates are usually on "local" (dir storage). If chosen storage doesn't support templates -> fallback.
  if ! pveam list "$store" >/dev/null 2>&1; then
    warn "pveam storage '$store' not available for templates; falling back to 'local'"
    store="local"
  fi

  # Update template list (quietly)
  pveam update >/dev/null 2>&1 || true

  # Download if missing
  if ! pveam list "$store" 2>/dev/null | awk '{print $2}' | grep -qx "$tpl"; then
    info "Downloading CT template to ${store}: ${tpl}"
    pveam download "$store" "$tpl" >/dev/null
  fi

  # Print template ref for pct create
  echo "${store}:vztmpl/${tpl}"
}

pve_build_net0() {
  local bridge="$1"
  local ip="$2"
  if [[ "$ip" == "dhcp" ]]; then
    echo "name=eth0,bridge=${bridge},ip=dhcp"
  else
    # expects CIDR e.g. 192.168.45.171/24 (no gateway here; can be set later if needed)
    echo "name=eth0,bridge=${bridge},ip=${ip}"
  fi
}

pve_create_ct() {
  need_cmd pct
  local ctid="$1" template="$2" hostname="$3"
  local cores="$4" memory="$5" swap="$6"
  local storage="$7" disk="$8"
  local bridge="$9" ip="${10}" unpriv="${11}"

  local net0 rootfs features
  net0="$(pve_build_net0 "$bridge" "$ip")"
  rootfs="${storage}:${disk}"
  features="nesting=1,keyctl=1,fuse=1"

  info "Creating CT ${ctid} (${hostname}) from ${template}"
  pct create "$ctid" "$template" \
    --hostname "$hostname" \
    --cores "$cores" \
    --memory "$memory" \
    --swap "$swap" \
    --net0 "$net0" \
    --rootfs "$rootfs" \
    --unprivileged "$unpriv" \
    --features "$features" \
    --start 0
}

pve_start_ct() {
  need_cmd pct
  local ctid="$1"
  info "Starting CT ${ctid}"
  pct start "$ctid" >/dev/null
}

# Wait for an IPv4 (non-empty) from pct exec "hostname -I"
pve_wait_ct_ip() {
  need_cmd pct awk
  local ctid="$1"
  local timeout="${2:-120}"
  local slept=0

  while (( slept < timeout )); do
    # hostname -I may return multiple; pick first IPv4
    local ip
    ip="$(pct exec "$ctid" -- bash -lc "hostname -I 2>/dev/null | awk '{print \$1}'" || true)"
    ip="${ip//$'\r'/}"
    ip="${ip//$'\n'/}"
    if [[ -n "$ip" ]]; then
      echo "$ip"
      return 0
    fi
    sleep 2
    slept=$((slept+2))
  done
  return 1
}

# Execute a command inside CT with proper shell
ct_exec() {
  need_cmd pct
  local ctid="$1"; shift
  pct exec "$ctid" -- bash -lc "$*"
}

# Upload a local file/stream into CT (uses pct push)
ct_push() {
  need_cmd pct
  local ctid="$1" src="$2" dst="$3"
  pct push "$ctid" "$src" "$dst"
}