#!/usr/bin/env python
"""
Python虚拟环境设置脚本

功能:
- 创建Python虚拟环境
- 安装项目依赖
- 生成激活脚本

用法:
    python setup_venv.py              # 创建venv并安装依赖
    python setup_venv.py --upgrade    # 升级已有依赖
    python setup_venv.py --clean      # 删除并重新创建venv
"""
import os
import sys
import subprocess
import argparse
from pathlib import Path


def run_command(cmd, cwd=None, check=True):
    """运行命令并显示输出"""
    print(f"执行: {' '.join(cmd) if isinstance(cmd, list) else cmd}")
    try:
        result = subprocess.run(
            cmd, 
            cwd=cwd, 
            check=check, 
            capture_output=True, 
            text=True,
            shell=True if isinstance(cmd, str) else False
        )
        if result.stdout:
            print(result.stdout)
        return result
    except subprocess.CalledProcessError as e:
        print(f"错误: {e}")
        if e.stderr:
            print(f"错误输出: {e.stderr}")
        if check:
            sys.exit(1)
        return e


def check_python():
    """检查Python版本"""
    version = sys.version_info
    print(f"Python版本: {version.major}.{version.minor}.{version.micro}")
    
    if version.major < 3 or (version.major == 3 and version.minor < 8):
        print("❌ 需要Python 3.8或更高版本")
        sys.exit(1)
    
    print("✓ Python版本符合要求")


def create_venv(venv_path, clean=False):
    """创建虚拟环境"""
    if clean and venv_path.exists():
        print(f"删除现有虚拟环境: {venv_path}")
        import shutil
        shutil.rmtree(venv_path)
    
    if venv_path.exists():
        print(f"✓ 虚拟环境已存在: {venv_path}")
        return
    
    print(f"创建虚拟环境: {venv_path}")
    run_command([sys.executable, "-m", "venv", str(venv_path)])
    print("✓ 虚拟环境创建成功")


def get_venv_python(venv_path):
    """获取虚拟环境中的Python路径"""
    if os.name == 'nt':  # Windows
        return venv_path / "Scripts" / "python.exe"
    else:  # Unix/Linux/macOS
        return venv_path / "bin" / "python"


def get_venv_pip(venv_path):
    """获取虚拟环境中的pip路径"""
    if os.name == 'nt':  # Windows
        return venv_path / "Scripts" / "pip.exe"
    else:  # Unix/Linux/macOS
        return venv_path / "bin" / "pip"


def install_dependencies(venv_path, upgrade=False):
    """安装项目依赖"""
    python_path = get_venv_python(venv_path)
    
    # 升级pip (使用python -m pip方式)
    print("升级pip...")
    run_command([str(python_path), "-m", "pip", "install", "--upgrade", "pip"])
    
    # 安装依赖
    requirements_file = Path("requirements.txt")
    if not requirements_file.exists():
        print("❌ requirements.txt文件不存在")
        return
    
    print("安装项目依赖...")
    cmd = [str(python_path), "-m", "pip", "install", "-r", "requirements.txt"]
    if upgrade:
        cmd.append("--upgrade")
    
    run_command(cmd)
    print("✓ 依赖安装完成")


def create_activation_scripts(venv_path):
    """创建激活脚本"""
    backend_dir = Path.cwd()
    
    # Windows批处理脚本
    activate_bat = backend_dir / "activate_venv.bat"
    with open(activate_bat, 'w', encoding='utf-8') as f:
        f.write(f"""@echo off
echo 激活Python虚拟环境...
call "{venv_path}\\Scripts\\activate.bat"
echo ✓ 虚拟环境已激活
echo.
echo 可用命令:
echo   python run.py          - 启动Flask应用
echo   python init_db.py      - 初始化数据库
echo   celery -A celery_worker worker - 启动Celery worker
echo   pytest                 - 运行测试
echo.
""")
    
    # Unix/Linux shell脚本
    activate_sh = backend_dir / "activate_venv.sh"
    with open(activate_sh, 'w', encoding='utf-8') as f:
        f.write(f"""#!/bin/bash
echo "激活Python虚拟环境..."
source "{venv_path}/bin/activate"
echo "✓ 虚拟环境已激活"
echo ""
echo "可用命令:"
echo "  python run.py          - 启动Flask应用"
echo "  python init_db.py      - 初始化数据库"
echo "  celery -A celery_worker worker - 启动Celery worker"
echo "  pytest                 - 运行测试"
echo ""
""")
    
    # 设置执行权限 (Unix/Linux)
    if os.name != 'nt':
        os.chmod(activate_sh, 0o755)
    
    print(f"✓ 激活脚本已创建:")
    print(f"  Windows: {activate_bat}")
    print(f"  Unix/Linux: {activate_sh}")


def main():
    parser = argparse.ArgumentParser(description='Python虚拟环境设置')
    parser.add_argument('--upgrade', action='store_true', help='升级依赖包')
    parser.add_argument('--clean', action='store_true', help='删除并重新创建虚拟环境')
    parser.add_argument('--venv-name', default='venv', help='虚拟环境目录名 (默认: venv)')
    args = parser.parse_args()
    
    print(f"\n{'='*50}")
    print("Python虚拟环境设置")
    print(f"{'='*50}\n")
    
    # 检查Python版本
    check_python()
    
    # 虚拟环境路径
    venv_path = Path.cwd() / args.venv_name
    
    # 创建虚拟环境
    create_venv(venv_path, clean=args.clean)
    
    # 安装依赖
    install_dependencies(venv_path, upgrade=args.upgrade)
    
    # 创建激活脚本
    create_activation_scripts(venv_path)
    
    print(f"\n{'='*50}")
    print("✓ 虚拟环境设置完成!")
    print(f"{'='*50}")
    
    print(f"\n激活虚拟环境:")
    if os.name == 'nt':  # Windows
        print(f"  activate_venv.bat")
        print(f"  或者: {venv_path}\\Scripts\\activate.bat")
    else:  # Unix/Linux
        print(f"  source activate_venv.sh")
        print(f"  或者: source {venv_path}/bin/activate")
    
    print(f"\n停用虚拟环境:")
    print(f"  deactivate")


if __name__ == '__main__':
    main()