"""把 Gitea Wiki 任务归档人工按需导出到 docs/task。"""

from __future__ import annotations

import argparse
import re
from pathlib import Path
from typing import Any

from new_task_archive import safe_title
from wiki_docs import (
    DEFAULT_CONFIG,
    ROOT,
    WikiClient,
    WikiDocsError,
    dirty_paths,
    load_config,
    parse_mirror,
    write_mirror,
)


TASK_PAGE_PATTERN = re.compile(r"^Task-(?P<number>\d+)-(?P<title>.+)$")


def task_revision(metadata: dict[str, Any], page_name: str) -> str:
    last_commit = metadata.get("last_commit")
    revision = last_commit.get("sha") if isinstance(last_commit, dict) else None
    if not isinstance(revision, str) or not revision:
        raise WikiDocsError(f"Wiki 页面缺少 revision：{page_name}")
    return revision


def existing_task_mirrors(root: Path = ROOT) -> dict[str, Path]:
    """按镜像头匹配已有文件，兼容历史自定义文件名。"""

    mirrors: dict[str, Path] = {}
    task_dir = root / "docs" / "task"
    if not task_dir.is_dir():
        return mirrors
    for path in task_dir.glob("*.md"):
        try:
            metadata, _ = parse_mirror(path.read_text(encoding="utf-8"))
        except (OSError, UnicodeDecodeError, WikiDocsError) as exc:
            raise WikiDocsError(f"已有任务镜像无效 {path.name}：{exc}") from exc
        page_name = metadata.get("wiki_page", "")
        if not TASK_PAGE_PATTERN.fullmatch(page_name):
            raise WikiDocsError(f"已有任务镜像页面名无效 {path.name}：{page_name}")
        if page_name in mirrors:
            raise WikiDocsError(f"任务页面存在重复本地镜像：{page_name}")
        mirrors[page_name] = path
    return mirrors


def task_target(page_name: str, root: Path = ROOT) -> Path:
    match = TASK_PAGE_PATTERN.fullmatch(page_name)
    if match is None:
        raise WikiDocsError(f"不是任务归档页面：{page_name}")
    title = safe_title(match.group("title"))
    if not title:
        raise WikiDocsError(f"任务归档标题无效：{page_name}")
    return root / "docs" / "task" / f"{match.group('number')}-{title}.md"


def export_task_archives(
    client: WikiClient, *, export_all: bool = False, root: Path = ROOT
) -> list[str]:
    """增量或全量读取任务归档；绝不删除本地文件。"""

    dirty = dirty_paths(["docs/task"], root)
    if dirty:
        raise WikiDocsError(
            "本地任务镜像存在未提交改动，已停止以防覆盖：\n" + "\n".join(dirty)
        )

    existing = existing_task_mirrors(root)
    pages = []
    for metadata in client.list_pages():
        title = metadata.get("title")
        if isinstance(title, str) and TASK_PAGE_PATTERN.fullmatch(title):
            pages.append((int(title.split("-", 2)[1]), title, metadata))
    pages.sort(key=lambda item: (item[0], item[1]))

    messages: list[str] = []
    targets: set[Path] = set()
    for _, page_name, metadata in pages:
        target = existing.get(page_name, task_target(page_name, root))
        if target in targets:
            raise WikiDocsError(f"多个任务页面映射到同一本地路径：{target.name}")
        targets.add(target)
        revision = task_revision(metadata, page_name)
        if not export_all and target.is_file():
            local_metadata, _ = parse_mirror(target.read_text(encoding="utf-8"))
            if (
                local_metadata.get("wiki_page") == page_name
                and local_metadata.get("wiki_revision") == revision
            ):
                messages.append(f"跳过：{target.relative_to(root)} <- {page_name}@{revision[:12]}")
                continue
        page = client.get_page_from_metadata(metadata, page_name)
        changed = write_mirror(target, page)
        action = "已导出" if changed else "无变化"
        messages.append(f"{action}：{target.relative_to(root)} <- {page_name}@{revision[:12]}")
    return messages


def main() -> int:
    parser = argparse.ArgumentParser(description="人工按需导出 Gitea Wiki 任务归档")
    parser.add_argument(
        "--all", action="store_true", help="全量读取全部线上任务归档；默认按 revision 增量"
    )
    parser.add_argument(
        "--config", default=str(DEFAULT_CONFIG), help="核心 Wiki 映射配置"
    )
    args = parser.parse_args()
    try:
        config = load_config(Path(args.config).resolve())
        messages = export_task_archives(
            WikiClient(config), export_all=args.all
        )
    except WikiDocsError as exc:
        print(f"错误：{exc}")
        return 1
    for message in messages:
        print(message)
    print("任务归档全量导出完成" if args.all else "任务归档增量导出完成")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())