#!/bin/bash
set -uo pipefail

# hostinfo.sh - Gather hardware/system info from a remote host
#
# Output: JSON object with system information

# -- Helper to escape JSON strings --
json_escape() {
    local str="$1"
    str="${str//\\/\\\\}"
    str="${str//\"/\\\"}"
    str="${str//$'\n'/\\n}"
    str="${str//$'\r'/\\r}"
    str="${str//$'\t'/\\t}"
    echo -n "$str"
}

# -- Gather system info --

HOSTNAME=$(hostname 2>/dev/null || echo "Unknown")

CPU=$(grep -m1 'model name' /proc/cpuinfo 2>/dev/null | cut -d: -f2 | xargs || echo "Unknown")
CPU_CORES=$(nproc 2>/dev/null || grep -c '^processor' /proc/cpuinfo 2>/dev/null || echo "0")

MOTHERBOARD=$(cat /sys/devices/virtual/dmi/id/board_name 2>/dev/null || echo "Unknown")

# RAM from free -m (used = total - available)
RAM_TOTAL_MB=$(free -m 2>/dev/null | awk 'NR==2{print $2}' || echo "0")
RAM_AVAIL_MB=$(free -m 2>/dev/null | awk 'NR==2{print $7}' || echo "0")
RAM_USED_MB=$(( RAM_TOTAL_MB - RAM_AVAIL_MB ))

# Disk root (strip trailing G from df -BG output)
DISK_ROOT_USED_GB=$(df -BG / 2>/dev/null | awk 'NR==2{gsub(/G/,"",$3); print $3}' || echo "0")
DISK_ROOT_TOTAL_GB=$(df -BG / 2>/dev/null | awk 'NR==2{gsub(/G/,"",$2); print $2}' || echo "0")

# Disk /tank (only if mounted)
DISK_TANK_USED_GB=""
DISK_TANK_TOTAL_GB=""
if [ -d /tank ] && mountpoint -q /tank 2>/dev/null; then
    DISK_TANK_USED_GB=$(df -BG /tank 2>/dev/null | awk 'NR==2{gsub(/G/,"",$3); print $3}' || echo "")
    DISK_TANK_TOTAL_GB=$(df -BG /tank 2>/dev/null | awk 'NR==2{gsub(/G/,"",$2); print $2}' || echo "")
fi

# IP addresses
IP_LOCAL=$(hostname -I 2>/dev/null | awk '{print $1}' || echo "Unknown")

IP_TAILSCALE=""
if command -v tailscale &>/dev/null; then
    IP_TAILSCALE=$(tailscale ip -4 2>/dev/null || echo "")
fi

IP_PUBLIC=""
if command -v curl &>/dev/null; then
    IP_PUBLIC=$(curl -s --max-time 3 ifconfig.me 2>/dev/null || echo "")
elif command -v wget &>/dev/null; then
    IP_PUBLIC=$(wget -qO- --timeout=3 ifconfig.me 2>/dev/null || echo "")
fi

# OS info
OS=$(grep PRETTY_NAME /etc/os-release 2>/dev/null | cut -d= -f2 | tr -d '"' || uname -o 2>/dev/null || echo "Unknown")
KERNEL=$(uname -r 2>/dev/null || echo "Unknown")
UPTIME=$(uptime -p 2>/dev/null || uptime 2>/dev/null || echo "Unknown")

# Docker
DOCKER_VERSION=""
if command -v docker &>/dev/null; then
    DOCKER_VERSION=$(docker --version 2>/dev/null | awk '{print $3}' | tr -d ',' || echo "")
fi

# GPU list (may have 0, 1, or multiple)
GPU_JSON="[]"
if command -v lspci &>/dev/null; then
    GPU_LINES=$(lspci 2>/dev/null | grep -i 'vga\|3d\|display' | sed 's/^[^ ]* //; s/VGA compatible controller: //; s/3D controller: //; s/Display controller: //' || true)
    if [ -n "$GPU_LINES" ]; then
        GPU_JSON="["
        first=true
        while IFS= read -r line; do
            [ -z "$line" ] && continue
            if [ "$first" = "true" ]; then
                first=false
            else
                GPU_JSON+=","
            fi
            GPU_JSON+="\""
            GPU_JSON+=$(json_escape "$line")
            GPU_JSON+="\""
        done <<< "$GPU_LINES"
        GPU_JSON+="]"
    fi
fi

# -- Output JSON --
echo -n '{'
echo -n '"hostname":"'; json_escape "$HOSTNAME"; echo -n '"'
echo -n ',"cpu":"'; json_escape "$CPU"; echo -n '"'
echo -n ',"cpu_cores":"'; json_escape "$CPU_CORES"; echo -n '"'
echo -n ',"motherboard":"'; json_escape "$MOTHERBOARD"; echo -n '"'
echo -n ',"gpu":'"$GPU_JSON"
echo -n ',"ram_used_mb":"'; json_escape "$RAM_USED_MB"; echo -n '"'
echo -n ',"ram_total_mb":"'; json_escape "$RAM_TOTAL_MB"; echo -n '"'
echo -n ',"disk_root_used_gb":"'; json_escape "$DISK_ROOT_USED_GB"; echo -n '"'
echo -n ',"disk_root_total_gb":"'; json_escape "$DISK_ROOT_TOTAL_GB"; echo -n '"'
echo -n ',"disk_tank_used_gb":"'; json_escape "$DISK_TANK_USED_GB"; echo -n '"'
echo -n ',"disk_tank_total_gb":"'; json_escape "$DISK_TANK_TOTAL_GB"; echo -n '"'
echo -n ',"ip_local":"'; json_escape "$IP_LOCAL"; echo -n '"'
echo -n ',"ip_tailscale":"'; json_escape "$IP_TAILSCALE"; echo -n '"'
echo -n ',"ip_public":"'; json_escape "$IP_PUBLIC"; echo -n '"'
echo -n ',"os":"'; json_escape "$OS"; echo -n '"'
echo -n ',"kernel":"'; json_escape "$KERNEL"; echo -n '"'
echo -n ',"uptime":"'; json_escape "$UPTIME"; echo -n '"'
echo -n ',"docker_version":"'; json_escape "$DOCKER_VERSION"; echo -n '"'
echo '}'