#!/bin/bash
# Installation script for ZMB Webui Backend on Raspberry Pi
# Run as root: sudo bash install.sh

set -e

echo "=== ZMB Webui Backend Installation ==="
echo ""

# Check if running as root
if [[ $EUID -ne 0 ]]; then
   echo "ERROR: This script must be run as root (use: sudo bash install.sh)"
   exit 1
fi

# Colors
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m'

# Configuration
INSTALL_PATH="/opt/zmb-webui"
VENV_PATH="${INSTALL_PATH}/venv"
SYSTEMD_USER="root"

echo -e "${YELLOW}Step 1: Checking prerequisites & architecture${NC}"

# Detect architecture
ARCH=$(uname -m)
echo "  - Architecture: $ARCH"
case $ARCH in
    aarch64) ARCH_NAME="ARM64 (Raspberry Pi)" ;;
    x86_64)  ARCH_NAME="AMD64 (64-bit)" ;;
    i686)    ARCH_NAME="x86 (32-bit)" ;;
    *)       ARCH_NAME="$ARCH (unknown)" ;;
esac
echo "    → $ARCH_NAME"

# Detect OS
if [ -f /etc/os-release ]; then
    . /etc/os-release
    OS_NAME="${NAME:-Unknown}"
    echo "  - OS: $OS_NAME"
else
    echo -e "${YELLOW}WARNING: Could not detect OS${NC}"
fi

echo "  - Python 3.11+"
python3 --version || { echo -e "${RED}ERROR: Python 3.11+ required${NC}"; exit 1; }

echo "  - ZFS tools"
which zpool > /dev/null || { echo -e "${RED}ERROR: zpool not found${NC}"; exit 1; }
which zfs > /dev/null || { echo -e "${RED}ERROR: zfs not found${NC}"; exit 1; }

echo "  - pip"
python3 -m pip --version > /dev/null || { echo -e "${RED}ERROR: pip not found${NC}"; exit 1; }

echo -e "${GREEN}✓ Prerequisites OK${NC}"
echo ""

echo -e "${YELLOW}Step 2: Creating installation directory${NC}"
mkdir -p "${INSTALL_PATH}"
cp -r . "${INSTALL_PATH}/backend"
echo -e "${GREEN}✓ Backend copied to ${INSTALL_PATH}/backend${NC}"
echo ""

echo -e "${YELLOW}Step 3: Creating Python virtual environment${NC}"
python3 -m venv "${VENV_PATH}"
source "${VENV_PATH}/bin/activate"
echo -e "${GREEN}✓ Virtual environment created${NC}"
echo ""

echo -e "${YELLOW}Step 4: Installing dependencies${NC}"
pip install --upgrade pip setuptools wheel > /dev/null
pip install -r "${INSTALL_PATH}/backend/requirements.txt"
echo -e "${GREEN}✓ Dependencies installed${NC}"
echo ""

echo -e "${YELLOW}Step 5: Setting up default admin user${NC}"
cd "${INSTALL_PATH}/backend"
python3 << EOF
import sys
sys.path.insert(0, '.')
from services.auth import auth_service

# Check if admin exists
if 'admin' not in auth_service.users:
    print("Creating default admin user...")
    auth_service.add_user('admin', 'admin123')
    print("✓ Admin user created (username: admin, password: admin123)")
    print("⚠️  CHANGE PASSWORD IMMEDIATELY!")
else:
    print("✓ Admin user already exists")
EOF
echo ""

echo -e "${YELLOW}Step 6: Installing systemd service${NC}"
cp deploy/zmb-webui-backend.service /etc/systemd/system/
systemctl daemon-reload
echo -e "${GREEN}✓ Systemd service installed${NC}"
echo ""

echo -e "${YELLOW}Step 7: Setting permissions${NC}"
chown -R root:root "${INSTALL_PATH}"
chmod 750 "${INSTALL_PATH}/backend"
chmod 640 "${INSTALL_PATH}/backend/config/users.json"
echo -e "${GREEN}✓ Permissions set${NC}"
echo ""

echo -e "${GREEN}=== Installation Complete ===${NC}"
echo ""
echo "Next steps:"
echo "  1. Review and update admin password:"
echo "     systemctl start zmb-webui-backend"
echo "     curl http://localhost:8000/health"
echo ""
echo "  2. Enable service to start on boot:"
echo "     systemctl enable zmb-webui-backend"
echo ""
echo "  3. Check logs:"
echo "     journalctl -u zmb-webui-backend -f"
echo ""
echo "  4. Test API:"
echo "     curl -X POST http://localhost:8000/api/auth/login \\"
echo "       -H 'Content-Type: application/json' \\"
echo "       -d '{\"username\":\"admin\",\"password\":\"admin123\"}'"
echo ""