#!/usr/bin/env python3
"""Build a portable v1 article package for the DWW11 userscript (standard library only)."""
from __future__ import annotations

import argparse
import base64
import json
import mimetypes
from pathlib import Path


def make_package(directory: str | Path, markdown: str | None = None) -> dict:
    """Return JSON-serializable data; no network access or publishing side effects."""
    root = Path(directory).expanduser().resolve(strict=True)
    if not root.is_dir():
        raise ValueError("文章目录不存在")
    choices = sorted(path for path in root.rglob("*") if path.is_file() and path.suffix.lower() == ".md")
    if markdown:
        selected = (root / markdown).resolve(strict=True)
    elif len(choices) == 1:
        selected = choices[0].resolve()
    else:
        raise ValueError("目录必须包含一个 Markdown 文件，或通过 --markdown 指定目录内相对路径")
    if not selected.is_relative_to(root) or selected.suffix.lower() != ".md" or not selected.is_file():
        raise ValueError("Markdown 必须位于所选文章目录内")
    images = []
    # Package local supported images. The importer uploads only those referenced by Markdown.
    for path in sorted(root.rglob("*")):
        if not path.is_file() or path.suffix.lower() not in {".jpg", ".jpeg", ".png", ".gif"}:
            continue
        if not path.resolve().is_relative_to(root):
            raise ValueError(f"图片符号链接指向目录外：{path.name}")
        if not 0 < path.stat().st_size < 20 * 1024 * 1024:
            raise ValueError(f"图片为空或达到 20 MB：{path.name}")
        images.append({"path": path.relative_to(root).as_posix(),
                       "mime": mimetypes.guess_type(path.name)[0] or "application/octet-stream",
                       "base64": base64.b64encode(path.read_bytes()).decode("ascii")})
    return {"schemaVersion": 1, "markdownPath": selected.relative_to(root).as_posix(),
            "markdown": selected.read_text(encoding="utf-8-sig"), "images": images}


def main() -> None:
    parser = argparse.ArgumentParser(description="把文章目录打包为油猴脚本可导入的 JSON；不上传或发布")
    parser.add_argument("directory", help="包含 Markdown 和图片的目录")
    parser.add_argument("--markdown", help="多个 Markdown 时指定目录内的相对路径")
    parser.add_argument("-o", "--output", help="输出文件路径；未指定时输出到标准输出")
    args = parser.parse_args()
    try:
        content = json.dumps(make_package(args.directory, args.markdown), ensure_ascii=False, indent=2)
        if args.output:
            output = Path(args.output).expanduser()
            # Never silently overwrite an article or an existing package.
            with output.open("x", encoding="utf-8") as handle:
                handle.write(content + "\n")
            print(json.dumps({"ok": True, "package": str(output.resolve())}, ensure_ascii=False))
        else:
            print(content)
    except (OSError, ValueError) as error:
        parser.exit(1, f"打包失败：{error}\n")


if __name__ == "__main__":
    main()