#!/usr/bin/env bash
# Snapshot RSS process groups inside a podman container + host-side CPU/PIDs.
# Usage: collect_container_resources.sh CONTAINER [OUT.json]
# Prints JSON to stdout (and writes OUT when given).
#
# Note: rootless podman often has no memory cgroup controller delegated
# (memory.current missing → podman stats shows 0B). We therefore use
# /proc VmRSS sums inside the container for memory, and podman stats for
# CPU% + PID count. /proc/loadavg inside the container is the *host* load.
set -euo pipefail

CTR="${1:-}"
OUT="${2:-}"
if [ -z "$CTR" ]; then
  echo "usage: $0 CONTAINER [OUT.json]" >&2
  exit 2
fi

ADMIN_LOG="${ADMIN_LOG:-${HOME}/koopa-admin-log}"
if [ ! -d "$ADMIN_LOG" ] && [ -d "${HOME}/src/koopa/koopa-admin-log" ]; then
  ADMIN_LOG="${HOME}/src/koopa/koopa-admin-log"
fi
MEM_SRC="${MEM_SNAPSHOT_SRC:-$ADMIN_LOG/scripts/taler-shared/mem-snapshot.sh}"
MEM_DST="${MEM_SNAPSHOT_DST:-/usr/local/lib/landing-mem-snapshot.sh}"

if ! podman inspect -f '{{.State.Running}}' "$CTR" 2>/dev/null | grep -qx true; then
  echo "{\"ok\":false,\"error\":\"container not running: $CTR\"}"
  exit 1
fi

if [ -f "$MEM_SRC" ]; then
  podman exec "$CTR" mkdir -p "$(dirname "$MEM_DST")" 2>/dev/null || true
  # Always refresh helper (fixes stale copies missing json_str / emit)
  podman cp "$MEM_SRC" "${CTR}:${MEM_DST}" 2>/dev/null || true
fi

set +e
raw=$(podman exec "$CTR" bash -c '
  set -e
  export PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
  if [ ! -f /usr/local/lib/landing-mem-snapshot.sh ]; then
    echo "{\"ok\":false,\"error\":\"mem-snapshot helper missing\"}"
    exit 1
  fi
  # shellcheck disable=SC1091
  . /usr/local/lib/landing-mem-snapshot.sh
  if ! declare -F mem_snapshot_emit >/dev/null 2>&1; then
    mem_snapshot_json
    loadavg=""
    [ -r /proc/loadavg ] && loadavg=$(awk "{print \$1\",\"\$2\",\"\$3}" /proc/loadavg)
    printf "{\"ok\":true,\"source\":\"mem-snapshot-legacy\",\"loadavg\":%s,\"memory\":{%s}}\n" \
      "\"$loadavg\"" "$MEM_JSON"
  else
    mem_snapshot_emit
  fi
' 2>/tmp/landing-mem-err.$$)
ec=$?
set -e

if [ "$ec" -ne 0 ] || [ -z "$raw" ]; then
  err=$(tr '\n' ' ' </tmp/landing-mem-err.$$ 2>/dev/null | head -c 200 || true)
  rm -f /tmp/landing-mem-err.$$
  printf '{"ok":false,"error":"podman exec failed: %s"}\n' "${err//\"/\'}"
  exit 1
fi
rm -f /tmp/landing-mem-err.$$

# Host-side: CPU% + PIDs via podman stats (works without memory controller)
stats_json=$(podman stats --no-stream --format json "$CTR" 2>/dev/null || true)

# Merge + normalize with Python
merged=$(
  RAW_JSON="$raw" STATS_JSON="$stats_json" CTR_NAME="$CTR" python3 - <<'PY'
import json, os, re

raw = os.environ.get("RAW_JSON") or ""
stats_raw = os.environ.get("STATS_JSON") or ""
ctr = os.environ.get("CTR_NAME") or ""

try:
    data = json.loads(raw)
except Exception as e:
    print(json.dumps({"ok": False, "error": f"invalid mem json: {e}"}))
    raise SystemExit(0)

if not isinstance(data, dict) or not data.get("ok"):
    print(json.dumps(data if isinstance(data, dict) else {"ok": False}))
    raise SystemExit(0)

mem = data.get("memory") if isinstance(data.get("memory"), dict) else {}
data["memory"] = mem

# Zero-group cleanup: UI should not show "0 B"
for key in ("taler", "java", "nginx", "postgres", "redis", "other"):
    n = mem.get(f"{key}_n")
    b = mem.get(f"{key}_rss_bytes")
    try:
        n = int(n) if n is not None else 0
    except Exception:
        n = 0
    try:
        b = int(b) if b is not None else 0
    except Exception:
        b = 0
    if n <= 0 or b <= 0:
        mem[f"{key}_n"] = 0
        mem[f"{key}_rss_bytes"] = 0
        mem[f"{key}_rss_human"] = None  # UI → "—"
        mem[f"{key}_rss_label"] = "—"

# Prefer process-sum label when cgroup missing
if not mem.get("cgroup_bytes") and mem.get("proc_sum_rss_human"):
    hum = mem.get("container_rss_human") or mem.get("proc_sum_rss_human")
    mem["container_rss_label"] = f"{hum} (proc)"
    mem["memory_basis"] = "proc_rss_sum"
elif mem.get("cgroup_limit_human") and mem.get("container_rss_human"):
    mem["container_rss_label"] = f"{mem['container_rss_human']} / {mem['cgroup_limit_human']}"
    mem["memory_basis"] = "cgroup"
else:
    mem["memory_basis"] = mem.get("memory_basis") or "proc_rss_sum"
    if mem.get("container_rss_human") and not mem.get("container_rss_label"):
        mem["container_rss_label"] = mem["container_rss_human"]

# loadavg inside rootless containers is usually the host's
data["loadavg_note"] = "host (shared; rootless container /proc/loadavg)"
data["loadavg_source"] = "host_via_container_proc"

# podman stats enrichment
cpu = None
pids = None
if stats_raw.strip():
    try:
        st = json.loads(stats_raw)
        if isinstance(st, list) and st:
            st = st[0]
        if isinstance(st, dict):
            cp = st.get("CPUPerc") or st.get("cpu_percent") or st.get("CPU")
            if cp is not None:
                s = str(cp).strip().rstrip("%")
                try:
                    cpu = float(s)
                except Exception:
                    cpu = None
            p = st.get("PIDs") or st.get("pids")
            if p is not None:
                try:
                    pids = int(str(p).strip())
                except Exception:
                    pids = None
            # mem from stats only if non-zero (usually 0B without memory controller)
            mu = st.get("MemUsage") or st.get("mem_usage") or ""
            m = re.match(r"^\s*([0-9.]+)\s*([KMGT]?i?B)\s*/\s*([0-9.]+)\s*([KMGT]?i?B)", str(mu), re.I)
            if m and float(m.group(1)) > 0:
                mem["podman_stats_mem"] = str(mu).strip()
    except Exception:
        pass

if cpu is not None:
    data["cpu_percent"] = cpu
    data["cpu_percent_label"] = f"{cpu:.2f}%"
if pids is not None:
    data["pids"] = pids
    mem["pids"] = pids

data["container"] = ctr
data["source"] = "mem-snapshot+podman-stats"
print(json.dumps(data, ensure_ascii=False))
PY
)

if ! printf '%s' "$merged" | python3 -c 'import json,sys; d=json.load(sys.stdin); assert d.get("ok")' 2>/dev/null; then
  # fall back to raw if merge failed
  merged="$raw"
fi

if [ -n "$OUT" ]; then
  printf '%s\n' "$merged" >"$OUT"
fi
printf '%s\n' "$merged"