#!/usr/bin/env bash
# update-system-status.sh — Writes system-status.json for the Nexus One AI portal.
# Run via cron every 30 seconds (cron minimum is 1 minute; use two entries offset by 30s).
#
# CRON SETUP (run as the portal server user):
#   crontab -e
#   Add these two lines:
#     * * * * * /opt/cezen-portal/update-system-status.sh
#     * * * * * sleep 30 && /opt/cezen-portal/update-system-status.sh
#
# OUTPUT: /opt/cezen-portal/system-status.json
# Adjust PORTAL_DIR below to match your actual portal directory.

PORTAL_DIR="/opt/cezen-portal"
OUT="$PORTAL_DIR/system-status.json"
TMP="$OUT.tmp"

# ── CPU load (1-minute average as a percentage of total cores) ──
CPU_CORES=$(nproc)
CPU_LOAD_RAW=$(awk '{print $1}' /proc/loadavg)
CPU_PCT=$(awk "BEGIN {v=$CPU_LOAD_RAW/$CPU_CORES*100; if(v>100)v=100; printf \"%d\", v}")

# ── RAM ──
read -r total used free shared buff cache available <<< $(free -b | awk 'NR==2{print $2,$3,$4,$5,$6,$7,$7}')
RAM_TOTAL_GB=$(awk "BEGIN {printf \"%.0f\", $total/1024/1024/1024}")
RAM_USED_GB=$(awk "BEGIN {printf \"%.0f\", ($total-$available)/1024/1024/1024}")
RAM_PCT=$(awk "BEGIN {printf \"%d\", ($total-$available)/$total*100}")

# ── Disk (root filesystem) ──
DISK_INFO=$(df -B1 / | awk 'NR==2{print $2,$3,$5}')
read -r DISK_TOTAL_B DISK_USED_B DISK_PCT_RAW <<< "$DISK_INFO"
DISK_PCT=${DISK_PCT_RAW/\%/}
DISK_TOTAL_GB=$(awk "BEGIN {printf \"%.1f\", $DISK_TOTAL_B/1024/1024/1024/1024}")
DISK_USED_GB=$(awk "BEGIN {printf \"%.0f\", $DISK_USED_B/1024/1024/1024}")

# ── GPU (NVIDIA) ──
if command -v nvidia-smi &>/dev/null; then
  GPU_INFO=$(nvidia-smi --query-gpu=utilization.gpu,temperature.gpu --format=csv,noheader,nounits 2>/dev/null | head -1)
  GPU_PCT=$(echo "$GPU_INFO" | awk -F', ' '{print $1}' | tr -d ' ')
  GPU_TEMP=$(echo "$GPU_INFO" | awk -F', ' '{print $2}' | tr -d ' ')
else
  GPU_PCT="null"
  GPU_TEMP="null"
fi

# ── Uptime ──
UPTIME_SEC=$(awk '{printf "%d", $1}' /proc/uptime)
UPTIME_DAYS=$((UPTIME_SEC / 86400))
UPTIME_HRS=$(( (UPTIME_SEC % 86400) / 3600 ))
UPTIME_MINS=$(( (UPTIME_SEC % 3600) / 60 ))
if [ "$UPTIME_DAYS" -gt 0 ]; then
  UPTIME_STR="${UPTIME_DAYS}d ${UPTIME_HRS}h ${UPTIME_MINS}m"
elif [ "$UPTIME_HRS" -gt 0 ]; then
  UPTIME_STR="${UPTIME_HRS}h ${UPTIME_MINS}m"
else
  UPTIME_STR="${UPTIME_MINS} minutes"
fi

# ── Write JSON atomically ──
TIMESTAMP=$(date -u +"%Y-%m-%dT%H:%M:%SZ")

cat > "$TMP" <<JSON
{
  "updated": "$TIMESTAMP",
  "cpu_pct": $CPU_PCT,
  "gpu_pct": $GPU_PCT,
  "gpu_temp": $GPU_TEMP,
  "ram_pct": $RAM_PCT,
  "ram_used": "${RAM_USED_GB} GB",
  "ram_total": "${RAM_TOTAL_GB} GB",
  "disk_pct": $DISK_PCT,
  "disk_used": "${DISK_USED_GB} GB",
  "disk_total": "${DISK_TOTAL_GB} TB",
  "uptime": "$UPTIME_STR"
}
JSON

mv "$TMP" "$OUT"