#!/bin/bash
# Startup script for Dissistant
# This script starts the Streamlit service and exposes it via Tailscale Serve

# Exit on error
set -e

# --- Configuration for Streamlit App ---
STREAMLIT_APP_FILE="app.py"
STREAMLIT_PORT="8502" 
STREAMLIT_PID_FILE="dissistant.pid"
STREAMLIT_LOG_FILE="dissistant.log"
# --- End Configuration ---

# Check if UV is installed
if ! command -v uv &> /dev/null; then
    echo "Error: UV is not installed. Please install UV first."
    echo "You can install UV with: pip install uv"
    exit 1
fi

# Create virtual environment if it doesn't exist
if [ ! -d ".venv" ]; then
    echo "Creating virtual environment..."
    uv venv
fi

# Activate virtual environment
echo "Activating virtual environment..."
source .venv/bin/activate

# Install dependencies
echo "Installing dependencies..."
uv pip install -r requirements.txt

# Kill any existing instances of the Streamlit app
echo "Stopping any existing instances of the Streamlit app..."
if [ -f "$STREAMLIT_PID_FILE" ]; then
    OLD_STREAMLIT_PID=$(cat $STREAMLIT_PID_FILE)
    if ps -p $OLD_STREAMLIT_PID > /dev/null; then
        kill $OLD_STREAMLIT_PID
        echo "Killed existing Streamlit app process with PID $OLD_STREAMLIT_PID"
        sleep 1 # Give it time to shut down
    else
        echo "No running Streamlit app process found with PID $OLD_STREAMLIT_PID"
    fi
fi
# Also try to kill any other streamlit processes for this specific app file and port
pkill -f "streamlit run $STREAMLIT_APP_FILE --server.port $STREAMLIT_PORT" || true
sleep 1

# Start the Streamlit app
echo "Starting Streamlit app on port $STREAMLIT_PORT..."
nohup streamlit run $STREAMLIT_APP_FILE --server.port $STREAMLIT_PORT --server.headless true > $STREAMLIT_LOG_FILE 2>&1 &
echo $! > $STREAMLIT_PID_FILE

# Check if the Streamlit service started successfully
sleep 3 # Give Streamlit a bit more time to start
if ! nc -z localhost $STREAMLIT_PORT; then
    echo "Error: Failed to start Streamlit app on port $STREAMLIT_PORT."
    cat $STREAMLIT_LOG_FILE # Output log file for debugging
    exit 1
else
    echo "Streamlit app started successfully on port $STREAMLIT_PORT."
fi

# Check if Tailscale is installed
if ! command -v tailscale &> /dev/null; then
    echo "Warning: Tailscale is not installed. The app will only be available locally."
    echo "Install Tailscale to expose the service over your tailnet."
else
    # Expose the service via Tailscale Serve
    echo "Exposing Streamlit app via Tailscale Serve on port $STREAMLIT_PORT..."
    echo "Setting up Funnel on port 10000..."
    tailscale funnel --https=10000 --bg localhost:$STREAMLIT_PORT
    
    # Get the Tailscale hostname
    HOSTNAME=$(tailscale status --json | jq -r '.Self.DNSName')
    if [ -n "$HOSTNAME" ]; then
        echo "App may be available at a Tailscale URL. Check 'tailscale status' for details."
        echo "If using a funnel, it might be https://$HOSTNAME/"
    else
        echo "App is exposed via Tailscale Serve, but couldn't determine the primary hostname."
        echo "Check 'tailscale status' for details."
    fi
fi

echo "Dissistant is now running!"
echo "Local URL: http://localhost:$STREAMLIT_PORT"
echo "Log file: $STREAMLIT_LOG_FILE"
echo "PID file: $STREAMLIT_PID_FILE"
echo ""
echo "If Tailscale is active, the app should be accessible via a Tailscale funnel URL."