#!/bin/bash

# CUDA Quantum MCP Server - Build and Deployment Script
# Automates the complete setup and deployment process

set -e  # Exit on any error

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m' # No Color

# Logging functions
log_info() {
    echo -e "${BLUE}ℹ️  $1${NC}"
}

log_success() {
    echo -e "${GREEN}✅ $1${NC}"
}

log_warning() {
    echo -e "${YELLOW}⚠️  $1${NC}"
}

log_error() {
    echo -e "${RED}❌ $1${NC}"
}

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

# System requirements check
check_requirements() {
    log_info "Checking system requirements..."
    
    # Check Node.js
    if command_exists node; then
        NODE_VERSION=$(node --version)
        log_success "Node.js found: $NODE_VERSION"
    else
        log_error "Node.js not found. Please install Node.js 18 or later."
        exit 1
    fi
    
    # Check Python
    if command_exists python3; then
        PYTHON_VERSION=$(python3 --version)
        log_success "Python found: $PYTHON_VERSION"
    else
        log_error "Python 3 not found. Please install Python 3.8 or later."
        exit 1
    fi
    
    # Check npm
    if command_exists npm; then
        NPM_VERSION=$(npm --version)
        log_success "npm found: $NPM_VERSION"
    else
        log_error "npm not found. Please install npm."
        exit 1
    fi
    
    # Check for GPU (optional)
    if command_exists nvidia-smi; then
        log_success "NVIDIA GPU detected"
        nvidia-smi --query-gpu=name --format=csv,noheader,nounits | head -1
    else
        log_warning "No NVIDIA GPU detected. GPU acceleration will not be available."
    fi
    
    log_success "System requirements check completed"
}

# Install CUDA Quantum
install_cudaq() {
    log_info "Installing CUDA Quantum..."
    
    # Check if CUDA Quantum is already installed
    if python3 -c "import cudaq" 2>/dev/null; then
        log_success "CUDA Quantum already installed"
        return 0
    fi
    
    # Install CUDA Quantum
    log_info "Installing CUDA Quantum via pip..."
    python3 -m pip install cudaq --user
    
    # Verify installation
    if python3 -c "import cudaq" 2>/dev/null; then
        log_success "CUDA Quantum installed successfully"
    else
        log_error "Failed to install CUDA Quantum"
        exit 1
    fi
}

# Install Node.js dependencies
install_node_deps() {
    log_info "Installing Node.js dependencies..."
    
    if [ ! -f "package.json" ]; then
        log_error "package.json not found. Are you in the right directory?"
        exit 1
    fi
    
    npm install
    
    log_success "Node.js dependencies installed"
}

# Install Python dependencies
install_python_deps() {
    log_info "Installing additional Python dependencies..."
    
    # Install common scientific computing packages
    python3 -m pip install --user numpy scipy matplotlib jupyter notebook
    
    log_success "Python dependencies installed"
}

# Build TypeScript
build_typescript() {
    log_info "Building TypeScript..."
    
    npm run build
    
    if [ -d "dist" ]; then
        log_success "TypeScript build completed"
    else
        log_error "TypeScript build failed"
        exit 1
    fi
}

# Set up environment
setup_environment() {
    log_info "Setting up environment..."
    
    # Copy environment template if .env doesn't exist
    if [ ! -f ".env" ]; then
        if [ -f ".env.example" ]; then
            cp .env.example .env
            log_info "Created .env from .env.example"
            log_warning "Please edit .env file with your configuration"
        else
            log_warning ".env.example not found, creating minimal .env"
            cat > .env << EOF
# CUDA Quantum MCP Server Configuration
NODE_ENV=development
CUDAQ_DEFAULT_TARGET=qpp-cpu
LOG_LEVEL=info
CUDAQ_PYTHON_PATH=$(which python3)
EOF
        fi
    else
        log_success "Environment file .env already exists"
    fi
    
    # Create logs directory
    mkdir -p logs
    log_success "Environment setup completed"
}

# Run tests
run_tests() {
    log_info "Running tests..."
    
    if [ "$1" = "--skip-tests" ]; then
        log_warning "Skipping tests as requested"
        return 0
    fi
    
    # Run unit tests
    if npm test 2>/dev/null; then
        log_success "All tests passed"
    else
        log_warning "Some tests failed or no tests configured"
    fi
}

# Validate installation
validate_installation() {
    log_info "Validating installation..."
    
    # Check if main files exist
    if [ -f "dist/index.js" ]; then
        log_success "Main server file found"
    else
        log_error "Main server file not found"
        exit 1
    fi
    
    # Test CUDA Quantum import
    if python3 -c "import cudaq; print('CUDA Quantum version:', cudaq.__version__ if hasattr(cudaq, '__version__') else 'unknown')" 2>/dev/null; then
        log_success "CUDA Quantum validation passed"
    else
        log_warning "CUDA Quantum validation failed"
    fi
    
    # Test server startup (quick test)
    log_info "Testing server startup..."
    timeout 5s node dist/index.js --test 2>/dev/null || log_warning "Server startup test inconclusive"
    
    log_success "Installation validation completed"
}

# Start server
start_server() {
    log_info "Starting CUDA Quantum MCP Server..."
    
    if [ "$1" = "--daemon" ]; then
        nohup npm start > logs/server.log 2>&1 &
        SERVER_PID=$!
        echo $SERVER_PID > logs/server.pid
        log_success "Server started as daemon (PID: $SERVER_PID)"
        log_info "Logs: tail -f logs/server.log"
        log_info "Stop: kill $SERVER_PID"
    else
        log_success "Starting server in foreground..."
        npm start
    fi
}

# Stop server daemon
stop_server() {
    if [ -f "logs/server.pid" ]; then
        SERVER_PID=$(cat logs/server.pid)
        if kill -0 $SERVER_PID 2>/dev/null; then
            kill $SERVER_PID
            rm logs/server.pid
            log_success "Server stopped (PID: $SERVER_PID)"
        else
            log_warning "Server process not running"
            rm -f logs/server.pid
        fi
    else
        log_warning "No server PID file found"
    fi
}

# Run integration examples
run_examples() {
    log_info "Running integration examples..."
    
    if [ -f "examples/integration_example.py" ]; then
        python3 examples/integration_example.py
    else
        log_warning "Integration examples not found"
    fi
}

# Create Docker image
build_docker() {
    log_info "Building Docker image..."
    
    if command_exists docker; then
        docker build -t mcp-quantum:latest .
        log_success "Docker image built: mcp-quantum:latest"
    else
        log_error "Docker not found. Please install Docker to build image."
        exit 1
    fi
}

# Deploy to production
deploy_production() {
    log_info "Deploying to production..."
    
    # Set production environment
    export NODE_ENV=production
    
    # Build with production settings
    npm run build
    
    # Install only production dependencies
    npm ci --only=production
    
    # Set up production environment
    if [ ! -f ".env.production" ]; then
        cp .env.example .env.production
        log_warning "Created .env.production - please configure for production"
    fi
    
    log_success "Production deployment prepared"
    log_info "Configure .env.production and start with: NODE_ENV=production npm start"
}

# Help function
show_help() {
    echo "CUDA Quantum MCP Server - Build and Deployment Script"
    echo
    echo "Usage: $0 [COMMAND] [OPTIONS]"
    echo
    echo "Commands:"
    echo "  setup         Complete setup (install deps, build, configure)"
    echo "  install       Install all dependencies"
    echo "  build         Build TypeScript code"
    echo "  test          Run tests"
    echo "  start         Start the server"
    echo "  stop          Stop server daemon"
    echo "  restart       Restart server daemon"
    echo "  status        Check server status"
    echo "  examples      Run integration examples"
    echo "  docker        Build Docker image"
    echo "  deploy        Deploy to production"
    echo "  clean         Clean build artifacts"
    echo "  help          Show this help"
    echo
    echo "Options:"
    echo "  --skip-tests  Skip running tests"
    echo "  --daemon      Start server as daemon"
    echo "  --gpu         Enable GPU support check"
    echo
    echo "Examples:"
    echo "  $0 setup                 # Complete setup"
    echo "  $0 start --daemon        # Start as daemon"
    echo "  $0 test --skip-tests     # Build without tests"
    echo "  $0 deploy                # Production deployment"
}

# Main execution
main() {
    local command="${1:-help}"
    shift || true
    
    case "$command" in
        setup)
            log_info "🚀 Starting complete setup..."
            check_requirements
            install_cudaq
            install_node_deps
            install_python_deps
            setup_environment
            build_typescript
            run_tests "$@"
            validate_installation
            log_success "🎉 Setup completed successfully!"
            log_info "Start the server with: $0 start"
            ;;
        install)
            check_requirements
            install_cudaq
            install_node_deps
            install_python_deps
            ;;
        build)
            build_typescript
            ;;
        test)
            run_tests "$@"
            ;;
        start)
            start_server "$@"
            ;;
        stop)
            stop_server
            ;;
        restart)
            stop_server
            sleep 2
            start_server "$@"
            ;;
        status)
            if [ -f "logs/server.pid" ]; then
                SERVER_PID=$(cat logs/server.pid)
                if kill -0 $SERVER_PID 2>/dev/null; then
                    log_success "Server running (PID: $SERVER_PID)"
                else
                    log_warning "Server PID file exists but process not running"
                fi
            else
                log_info "Server not running"
            fi
            ;;
        examples)
            run_examples
            ;;
        docker)
            build_docker
            ;;
        deploy)
            deploy_production
            ;;
        clean)
            log_info "Cleaning build artifacts..."
            rm -rf dist/ node_modules/ logs/ coverage/
            log_success "Clean completed"
            ;;
        help|--help|-h)
            show_help
            ;;
        *)
            log_error "Unknown command: $command"
            show_help
            exit 1
            ;;
    esac
}

# Script entry point
if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
    main "$@"
fi