#!/bin/bash
# Detect system type on remote host
# Usage: ./detect-system.sh <hostname>

TARGET_HOST="$1"
SSH_USER="${SSH_USER:-root}"
SSH_PASSWORD="${SSH_PASSWORD:-}"

if [ -z "$TARGET_HOST" ]; then
    echo "Usage: $0 <hostname>" >&2
    exit 1
fi

# SSH options for faster connection
SSH_OPTS="-o ConnectTimeout=10 -o StrictHostKeyChecking=no"

# Add BatchMode only if no password is provided
if [ -z "$SSH_PASSWORD" ]; then
    SSH_OPTS="$SSH_OPTS -o BatchMode=yes"
fi

# Function to try SSH command
try_ssh() {
    local user="$1"
    local command="$2"
    
    # Add small delay to avoid SSH rate limiting
    sleep 0.5
    
    if [ -n "$SSH_PASSWORD" ]; then
        # Use sshpass if password is provided
        if command -v sshpass >/dev/null 2>&1; then
            sshpass -p "$SSH_PASSWORD" ssh $SSH_OPTS ${user}@${TARGET_HOST} "$command" 2>/dev/null
        else
            # Fallback: try without sshpass (will fail if password needed)
            ssh $SSH_OPTS ${user}@${TARGET_HOST} "$command" 2>/dev/null
        fi
    else
        ssh $SSH_OPTS ${user}@${TARGET_HOST} "$command" 2>/dev/null
    fi
}

# Try to detect system type
# If SSH_USER is specified and not root, try Home Assistant first
if [ "$SSH_USER" != "root" ] && [ -n "$SSH_USER" ]; then
    if try_ssh "$SSH_USER" "test -f /usr/bin/ha || (docker ps 2>/dev/null | grep -q homeassistant)" >/dev/null 2>&1; then
        echo "homeassistant:${SSH_USER}"
        exit 0
    fi
fi

# Try root for standard systems
if try_ssh "root" "test -f /usr/bin/pvesh" >/dev/null 2>&1; then
    echo "proxmox"
    exit 0
elif try_ssh "root" "test -f /usr/local/bin/freenas-version || test -f /usr/local/bin/truenas-version" >/dev/null 2>&1; then
    echo "truenas"
    exit 0
elif try_ssh "root" "test -f /usr/local/sbin/pfSsh.php" >/dev/null 2>&1; then
    echo "pfsense"
    exit 0
elif try_ssh "root" "test -f /usr/sbin/univention-config-registry" >/dev/null 2>&1; then
    echo "ucs"
    exit 0
fi

# Try non-root users for Home Assistant if not already tried
for user in icke homeassistant; do
    if [ "$user" = "$SSH_USER" ]; then
        continue  # Already tried above
    fi
    
    if try_ssh "$user" "test -f /usr/bin/ha || (docker ps 2>/dev/null | grep -q homeassistant)" >/dev/null 2>&1; then
        echo "homeassistant:${user}"
        exit 0
    fi
done

echo "unknown"
exit 0