#!/bin/bash
set -e

# UnitForge Web Server Startup Script
# This script starts the FastAPI development server for UnitForge

# Load centralized color utility
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
source "${SCRIPT_DIR}/scripts/colors.sh"

# Configuration
DEFAULT_HOST="0.0.0.0"
DEFAULT_PORT="8000"
BACKEND_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/backend"

# Parse command line arguments
HOST=${DEFAULT_HOST}
PORT=${DEFAULT_PORT}
RELOAD=true
LOG_LEVEL="info"
USE_UV=true

usage() {
    echo "Usage: $0 [OPTIONS]"
    echo ""
    echo "Options:"
    echo "  -h, --host HOST        Host to bind to (default: ${DEFAULT_HOST})"
    echo "  -p, --port PORT        Port to bind to (default: ${DEFAULT_PORT})"
    echo "  --no-reload           Disable auto-reload"
    echo "  --log-level LEVEL     Log level (debug, info, warning, error, critical)"

    echo "  --help                Show this help message"
    echo ""
    echo "Examples:"
    echo "  $0                    # Start with default settings"
    echo "  $0 -h 127.0.0.1 -p 3000  # Custom host and port"
    echo "  $0 --no-reload        # Start without auto-reload"

}

while [[ $# -gt 0 ]]; do
    case $1 in
        -h|--host)
            HOST="$2"
            shift 2
            ;;
        -p|--port)
            PORT="$2"
            shift 2
            ;;
        --no-reload)
            RELOAD=false
            shift
            ;;
        --log-level)
            LOG_LEVEL="$2"
            shift 2
            ;;

        --help)
            usage
            exit 0
            ;;
        *)
            echo -e "${RED}Error: Unknown option $1${NC}"
            usage
            exit 1
            ;;
    esac
done

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

# Function to check if port is available
check_port() {
    if command_exists lsof; then
        if lsof -Pi :$1 -sTCP:LISTEN -t >/dev/null 2>&1; then
            return 1
        fi
    elif command_exists netstat; then
        if netstat -tuln 2>/dev/null | grep -q ":$1 "; then
            return 1
        fi
    fi
    return 0
}

# Print banner
echo -e "${BLUE}"
echo "╔══════════════════════════════════════════════╗"
echo "║              UnitForge Server                ║"
echo "║    Systemd Unit File Creator & Manager       ║"
echo "╚══════════════════════════════════════════════╝"
echo -e "${NC}"

# Check if we're in the right directory
if [[ ! -d "${BACKEND_DIR}" ]]; then
    echo -e "${RED}Error: Backend directory not found at ${BACKEND_DIR}${NC}"
    echo "Please run this script from the unitforge project root directory."
    exit 1
fi

# Check if Python is available
if ! command_exists python3; then
    echo -e "${RED}Error: Python 3 is not installed or not in PATH${NC}"
    exit 1
fi

# Check Python version
PYTHON_VERSION=$(python3 -c 'import sys; print(".".join(map(str, sys.version_info[:2])))')
REQUIRED_VERSION="3.8"

if ! python3 -c "import sys; exit(0 if sys.version_info >= (3, 8) else 1)"; then
    echo -e "${RED}Error: Python ${REQUIRED_VERSION}+ is required, but ${PYTHON_VERSION} is installed${NC}"
    exit 1
fi

echo -e "${GREEN}✓ Python ${PYTHON_VERSION} found${NC}"

# Check for uv
if ! command_exists uv; then
    echo -e "${RED}Error: uv package manager is required${NC}"
    echo "Install it with: curl -LsSf https://astral.sh/uv/install.sh | sh"
    exit 1
fi
echo -e "${GREEN}✓ uv package manager found${NC}"

# Change to backend directory
cd "${BACKEND_DIR}"

# Check if virtual environment is activated
if [[ -z "${VIRTUAL_ENV}" ]]; then
    # Check if .venv exists in parent directory
    if [[ -d "../.venv" ]]; then
        echo -e "${YELLOW}Activating virtual environment...${NC}"
        source ../.venv/bin/activate
        success "Virtual environment activated"
    else
        echo -e "${YELLOW}ℹ No virtual environment detected${NC}"
        echo -e "${YELLOW}Run 'make setup-dev' to create environment with uv${NC}"
    fi
fi

# Check if requirements are installed
info "Checking dependencies..."

MISSING_DEPS=()
REQUIRED_PACKAGES=("fastapi" "uvicorn" "click" "pydantic" "jinja2")

for package in "${REQUIRED_PACKAGES[@]}"; do
    if ! python3 -c "import ${package}" 2>/dev/null; then
        MISSING_DEPS+=("${package}")
    fi
done

if [[ ${#MISSING_DEPS[@]} -gt 0 ]]; then
    echo -e "${YELLOW}Missing dependencies: ${MISSING_DEPS[*]}${NC}"
    echo -e "${YELLOW}Installing dependencies with uv...${NC}"

    if ! uv pip install -r requirements.txt; then
        echo -e "${RED}Error: Failed to install dependencies with uv${NC}"
        echo "You may need to:"
        echo "1. Create a virtual environment: uv venv"
        echo "2. Activate it: source .venv/bin/activate"
        echo "3. Install dependencies: uv pip install -r requirements.txt"
        echo "4. Or run 'make setup-dev' for complete setup"
        exit 1
    fi
    success "Dependencies installed"
else
    success "Dependencies already installed"
fi

# Check if port is available
if ! check_port "${PORT}"; then
    echo -e "${YELLOW}Warning: Port ${PORT} appears to be in use${NC}"
    echo "The server may fail to start if another process is using this port."
    read -p "Continue anyway? (y/N): " -n 1 -r
    echo
    if [[ ! $REPLY =~ ^[Yy]$ ]]; then
        echo "Aborted."
        exit 1
    fi
fi

# Build uvicorn command
UVICORN_CMD="python3 -m uvicorn app.main:app --host ${HOST} --port ${PORT} --log-level ${LOG_LEVEL}"

if [[ "${RELOAD}" == "true" ]]; then
    UVICORN_CMD="${UVICORN_CMD} --reload"
fi

# Print server info
echo ""
echo -e "${GREEN}Starting UnitForge server...${NC}"
echo -e "${BLUE}Host:${NC} ${HOST}"
echo -e "${BLUE}Port:${NC} ${PORT}"
echo -e "${BLUE}Auto-reload:${NC} ${RELOAD}"
echo -e "${BLUE}Log level:${NC} ${LOG_LEVEL}"
echo -e "${BLUE}Package manager:${NC} uv"
echo ""
echo -e "${GREEN}Server will be available at:${NC}"
if [[ "${HOST}" == "0.0.0.0" ]]; then
    echo -e "  ${BLUE}http://localhost:${PORT}${NC}"
    echo -e "  ${BLUE}http://127.0.0.1:${PORT}${NC}"
else
    echo -e "  ${BLUE}http://${HOST}:${PORT}${NC}"
fi
echo ""
echo -e "${GREEN}API Documentation:${NC}"
if [[ "${HOST}" == "0.0.0.0" ]]; then
    echo -e "  ${BLUE}http://localhost:${PORT}/api/docs${NC}"
else
    echo -e "  ${BLUE}http://${HOST}:${PORT}/api/docs${NC}"
fi
echo ""
echo -e "${YELLOW}Press Ctrl+C to stop the server${NC}"
echo ""

# Set up signal handling for graceful shutdown
trap 'echo -e "\n${YELLOW}Shutting down UnitForge server...${NC}"; exit 0' INT TERM

# Start the server
exec ${UVICORN_CMD}