import os
import sys
import shutil
import subprocess
from modelscope.hub.snapshot_download import snapshot_download
from dotenv import load_dotenv

load_dotenv()


def discover_models():
    """从环境变量中发现所有模型"""
    models = {}
    for key, value in os.environ.items():
        if key.endswith('_MODEL_ID'):
            prefix = key[:-9]
            service_name = os.getenv(f'{prefix}_SERVICE_NAME', f'{prefix.lower()}_classifier')
            service_folder = service_name.replace('_classifier', '')
            model_type = os.getenv(f'{prefix}_TYPE', 'general')

            models[prefix.lower()] = {
                'prefix': prefix,
                'model_id': value,
                'port': os.getenv(f'{prefix}_PORT', '5002'),
                'service_name': service_name,
                'model_dir': os.getenv(f'{prefix}_MODEL_DIR', f'/app/services/{service_folder}/model'),
                'service_folder': service_folder,
                'model_type': model_type,
                'cache_dir': os.path.join('/app/model_cache', prefix.lower())
            }
    return models


def find_model_files(cache_dir):
    """查找实际的模型文件位置"""
    if os.path.exists(cache_dir):
        for root, dirs, files in os.walk(cache_dir):
            if any(f.endswith(('.safetensors', '.bin')) for f in files):
                return root
    return None


def download_model(name, config):
    """下载单个模型"""
    print("=" * 50)
    print(f"Processing {name} model...")
    print(f"Model ID: {config['model_id']}")
    print(f"Target: {config['model_dir']}")
    print(f"Cache: {config['cache_dir']}")
    print("=" * 50)

    try:
        # 确保目录存在
        os.makedirs(config['model_dir'], exist_ok=True)
        os.makedirs(config['cache_dir'], exist_ok=True)

        # 检查是否已有模型文件
        if os.path.exists(config['model_dir']):
            files = [f for f in os.listdir(config['model_dir']) if f.endswith(('.safetensors', '.bin'))]
            if files:
                print(f"✓ Model already exists in {config['model_dir']} (found {len(files)} files)")
                return True

        # 登录 ModelScope
        token = os.getenv('MODELSCOPE_TOKEN', '')
        if token:
            result = subprocess.run(
                ['modelscope', 'login', '--token', token],
                capture_output=True,
                text=True
            )
            if result.returncode == 0:
                print("✓ ModelScope login successful")
            else:
                print(f"⚠️  ModelScope login failed: {result.stderr}")

        # 下载模型
        print(f"Downloading model to {config['cache_dir']}...")
        snapshot_download(
            model_id=config['model_id'],
            cache_dir=config['cache_dir'],
            revision="master",
            ignore_file_pattern=[".git", ".gitattributes"]
        )

        # 查找实际模型文件
        src_dir = find_model_files(config['cache_dir'])

        if src_dir is None:
            print(f"✗ Could not find model files in downloaded content")
            return False

        print(f"✓ Found model files in: {src_dir}")

        # 复制文件到目标目录
        print(f"Copying files to {config['model_dir']}...")
        copied_count = 0
        for file in os.listdir(src_dir):
            src_file = os.path.join(src_dir, file)
            if os.path.isfile(src_file):
                dest_file = os.path.join(config['model_dir'], file)
                shutil.copy2(src_file, dest_file)
                copied_count += 1
                print(f"  Copied: {file}")

        if copied_count > 0:
            print(f"✓ {name} model downloaded successfully! ({copied_count} files)")
            return True
        else:
            print(f"✗ No files copied")
            return False

    except PermissionError as e:
        print(f"✗ Permission error: {e}")
        return False
    except Exception as e:
        print(f"✗ Failed to download {name} model: {e}")
        return False


def main():
    print("=" * 50)
    print("Model Download Script")
    print("=" * 50)

    import pwd
    current_user = pwd.getpwuid(os.getuid()).pw_name
    print(f"Running as user: {current_user}")
    print("=" * 50)

    models = discover_models()

    if not models:
        print("⚠️  No models found in .env file!")
        sys.exit(1)

    print(f"\nFound {len(models)} model(s):")
    for name, config in models.items():
        print(f"  {name}: {config['model_id']}")
        print(f"    Target: {config['model_dir']}")
        print(f"    Type:   {config['model_type']}")
    print("")

    print("=" * 50)
    print("Processing models...")
    print("=" * 50)

    success_count = 0
    for name, config in models.items():
        if download_model(name, config):
            success_count += 1
        print("")

    print("=" * 50)
    print(f"Processing completed: {success_count}/{len(models)} models")
    print("=" * 50)

    if success_count < len(models):
        sys.exit(1)


if __name__ == "__main__":
    main()