#!/usr/bin/env python3
"""打包 Lambda 函数为 zip，跨平台 (Windows/Linux/Mac)。"""
import os
import sys
import shutil
import zipfile
import subprocess

SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
LAMBDAS_DIR = os.path.join(SCRIPT_DIR, '..', 'lambdas')
LAMBDAS_DIR = os.path.normpath(LAMBDAS_DIR)

FUNCTIONS = ['submit', 'download', 'transcribe_start', 'transcribe_check', 'summarize', 'notify']


def build_layer():
    """打包 Lambda Layer (requests + pycryptodome)"""
    print("Building Lambda layer...")
    layer_dir = os.path.join(LAMBDAS_DIR, 'layer_build', 'python')
    layer_zip = os.path.join(LAMBDAS_DIR, 'layer.zip')

    if os.path.exists(os.path.join(LAMBDAS_DIR, 'layer_build')):
        shutil.rmtree(os.path.join(LAMBDAS_DIR, 'layer_build'))
    os.makedirs(layer_dir)

    # 全部指定 Linux 平台安装，确保 native 包兼容 Lambda
    subprocess.check_call([
        sys.executable, '-m', 'pip', 'install',
        'requests', 'pycryptodome', 'openai', 'tiktoken',
        '--platform', 'manylinux2014_x86_64',
        '--implementation', 'cp',
        '--python-version', '3.12',
        '--only-binary=:all:',
        '-t', layer_dir, '-q',
    ])

    with zipfile.ZipFile(layer_zip, 'w', zipfile.ZIP_DEFLATED) as zf:
        for root, dirs, files in os.walk(os.path.join(LAMBDAS_DIR, 'layer_build')):
            for f in files:
                full = os.path.join(root, f)
                arcname = os.path.relpath(full, os.path.join(LAMBDAS_DIR, 'layer_build'))
                zf.write(full, arcname)

    shutil.rmtree(os.path.join(LAMBDAS_DIR, 'layer_build'))
    size = os.path.getsize(layer_zip) / 1024 / 1024
    print(f"  layer.zip ({size:.1f} MB)")


def build_function(name):
    """打包单个 Lambda 函数"""
    zip_path = os.path.join(LAMBDAS_DIR, f'{name}.zip')
    with zipfile.ZipFile(zip_path, 'w', zipfile.ZIP_DEFLATED) as zf:
        zf.write(os.path.join(LAMBDAS_DIR, f'{name}.py'), f'{name}.py')
        zf.write(os.path.join(LAMBDAS_DIR, 'shared.py'), 'shared.py')
    size = os.path.getsize(zip_path) / 1024
    print(f"  {name}.zip ({size:.1f} KB)")


def main():
    print(f"Lambda 目录: {LAMBDAS_DIR}\n")
    build_layer()
    print()
    for fn in FUNCTIONS:
        build_function(fn)
    print("\n完成!")


if __name__ == '__main__':
    main()