#!/bin/bash

# MYP Backend Installation Script for Debian
# This script installs and configures the MYP backend on a Debian-based system

set -e  # Exit immediately if a command exits with non-zero status
SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
LOG_FILE="$SCRIPT_DIR/backend-install.log"

# Function for logging with timestamps
log() {
    local timestamp=$(date +"%Y-%m-%d %H:%M:%S")
    echo -e "[$timestamp] $1" | tee -a "$LOG_FILE"
}

# Function to check if a command exists
command_exists() {
    command -v "$1" >/dev/null 2>&1
}

# Clear log file
> "$LOG_FILE"

log "===== Starting MYP Backend Installation ====="
log "Installation directory: $SCRIPT_DIR"

# Check for root privileges
if [ "$EUID" -ne 0 ]; then
    log "ERROR: This script must be run as root"
    exit 1
fi

# System update
log "Updating system packages..."
apt update -y >> "$LOG_FILE" 2>&1
apt upgrade -y >> "$LOG_FILE" 2>&1

# Install required packages
log "Installing required packages..."
apt install -y python3 python3-venv python3-pip sqlite3 >> "$LOG_FILE" 2>&1

# Create Python virtual environment
log "Creating Python virtual environment..."
cd "$SCRIPT_DIR"
if [ -d "venv" ]; then
    log "Found existing virtual environment, removing..."
    rm -rf venv
fi

python3 -m venv venv >> "$LOG_FILE" 2>&1
source venv/bin/activate
log "Upgrading pip..."
pip install --upgrade pip >> "$LOG_FILE" 2>&1

# Install Python dependencies
log "Installing Python dependencies..."
if [ -f "requirements.txt" ]; then
    pip install -r requirements.txt >> "$LOG_FILE" 2>&1
else
    log "ERROR: requirements.txt not found"
    exit 1
fi

# Setup Bootstrap for offline usage
log "Setting up Bootstrap for offline usage..."
mkdir -p "$SCRIPT_DIR/static/css" "$SCRIPT_DIR/static/js"

# Download non-minified Bootstrap CSS and JS files
log "Downloading Bootstrap files for offline usage..."
wget -q -O "$SCRIPT_DIR/static/css/bootstrap.css" "https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.css" || {
    log "WARNING: Could not download Bootstrap CSS. Creating placeholder..."
    echo "/* Bootstrap 5.3.2 offline placeholder */" > "$SCRIPT_DIR/static/css/bootstrap.css"
    echo "/* Please manually download the full unminified version from: */" >> "$SCRIPT_DIR/static/css/bootstrap.css"
    echo "/* https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.css */" >> "$SCRIPT_DIR/static/css/bootstrap.css"
}

wget -q -O "$SCRIPT_DIR/static/js/bootstrap.bundle.js" "https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/js/bootstrap.bundle.js" || {
    log "WARNING: Could not download Bootstrap JS. Creating placeholder..."
    echo "/* Bootstrap 5.3.2 bundle offline placeholder */" > "$SCRIPT_DIR/static/js/bootstrap.bundle.js"
    echo "/* Please manually download the full unminified version from: */" >> "$SCRIPT_DIR/static/js/bootstrap.bundle.js"
    echo "/* https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/js/bootstrap.bundle.js */" >> "$SCRIPT_DIR/static/js/bootstrap.bundle.js"
}

# Create database directory if it doesn't exist
log "Setting up database directories..."
mkdir -p instance/backups

# Check if .env file exists
if [ ! -f "$SCRIPT_DIR/.env" ]; then
    log "Creating .env file template (IMPORTANT: Edit with your configuration)..."
    cat > "$SCRIPT_DIR/.env" << EOF
# MYP Backend Environment Configuration
# IMPORTANT: Replace these values with your actual configuration!

SECRET_KEY=generate_a_secure_random_key
DATABASE_PATH=instance/myp_backend.db

# Tapo P115 Smart Plug credentials
TAPO_USERNAME=your_tapo_email
TAPO_PASSWORD=your_tapo_password

# Printer to Smart Plug mapping (JSON format)
# Format: {"Printer Name": "192.168.x.x", "Another Printer": "192.168.x.y"}
PRINTERS={"Example Printer": "192.168.1.100"}
EOF
    log "ATTENTION: .env file has been created with placeholder values"
    log "           Please edit .env with your actual configuration before continuing"
    read -p "Press Enter to continue after editing .env..."
fi

# Initialize the database
log "Initializing database..."
if [ -f "$SCRIPT_DIR/development/initialize_myp_database.sh" ]; then
    bash "$SCRIPT_DIR/development/initialize_myp_database.sh" >> "$LOG_FILE" 2>&1
    log "Database initialized successfully"
else
    log "WARNING: initialize_myp_database.sh not found, manual setup may be required"
    # Create empty database
    touch instance/myp_backend.db
    log "Created empty database file"
fi

# Setup cron job
log "Setting up cron job for maintenance tasks..."
CURRENT_USER=$(who am i | awk '{print $1}')
CRON_JOB="*/5 * * * * cd $SCRIPT_DIR && source venv/bin/activate && flask check-jobs"

# Create a temporary file with the current crontab plus our new job
TEMP_CRON=$(mktemp)
crontab -l 2>/dev/null | grep -v "$SCRIPT_DIR.*check-jobs" > "$TEMP_CRON" || true
echo "$CRON_JOB" >> "$TEMP_CRON"
crontab "$TEMP_CRON"
rm "$TEMP_CRON"

log "Cron job installed. Maintenance tasks will run every 5 minutes"

# Test the application
log "Testing backend application..."
source venv/bin/activate
cd "$SCRIPT_DIR"
if python -c "import app" 2>> "$LOG_FILE"; then
    log "Import test successful"
else
    log "WARNING: Import test failed, check the log file for details"
fi

# Generate systemd service file
log "Creating systemd service..."
cat > /etc/systemd/system/myp-backend.service << EOF
[Unit]
Description=MYP Backend Service
After=network.target

[Service]
User=$CURRENT_USER
WorkingDirectory=$SCRIPT_DIR
ExecStart=$SCRIPT_DIR/venv/bin/gunicorn --bind 0.0.0.0:5000 app:app
Restart=always
RestartSec=10

[Install]
WantedBy=multi-user.target
EOF

# Reload systemd and enable the service
systemctl daemon-reload
systemctl enable myp-backend.service

log "Installation complete!"
log ""
log "To start the backend service, run: systemctl start myp-backend"
log "To check service status, run: systemctl status myp-backend"
log "To view logs, run: journalctl -u myp-backend -f"
log ""
log "Configuration file is at: $SCRIPT_DIR/.env"
log "Make sure to configure your Tapo smart plug credentials and printer mapping in this file"
log ""
log "For development mode, run: cd $SCRIPT_DIR && source venv/bin/activate && python app.py"
log ""
log "To run tests, use: cd $SCRIPT_DIR && source venv/bin/activate && python -m unittest development/tests/tests.py"
log ""
log "For issues, check the log file at: $LOG_FILE"