#!/usr/bin/env python3
"""Shared helpers for the software copyright materials skill."""

from __future__ import annotations

import json
import os
import re
from pathlib import Path
from typing import Any, Iterable


EXCLUDE_DIRS = {
    ".git",
    ".hg",
    ".svn",
    ".idea",
    ".vscode",
    "__pycache__",
    "node_modules",
    "dist",
    "build",
    ".next",
    ".nuxt",
    ".output",
    "coverage",
    "target",
    "vendor",
    "软件著作权申请资料",
    "software-copyright-materials",
}

CODE_EXTS = {
    ".vue",
    ".ts",
    ".tsx",
    ".js",
    ".jsx",
    ".mjs",
    ".cjs",
    ".css",
    ".scss",
    ".sass",
    ".less",
    ".html",
    ".svelte",
    ".astro",
    ".json",
    ".md",
}

FRONTEND_EXTS = {
    ".vue",
    ".ts",
    ".tsx",
    ".js",
    ".jsx",
    ".mjs",
    ".css",
    ".scss",
    ".sass",
    ".less",
    ".html",
    ".svelte",
    ".astro",
}

SUPPLEMENT_CODE_EXTS = {
    ".py",
    ".java",
    ".go",
    ".rs",
    ".cs",
    ".php",
    ".rb",
    ".kt",
    ".swift",
    ".sql",
    ".sh",
    ".toml",
    ".yml",
    ".yaml",
    ".json",
}

COPYRIGHT_CODE_EXTS = FRONTEND_EXTS | SUPPLEMENT_CODE_EXTS

LOCK_FILES = {
    "package-lock.json",
    "pnpm-lock.yaml",
    "yarn.lock",
    "bun.lockb",
    "bun.lock",
}


def repo_root_from_script() -> Path:
    return Path(__file__).resolve().parents[3]


def is_excluded(path: Path) -> bool:
    parts = set(path.parts)
    if parts & EXCLUDE_DIRS:
        return True
    name = path.name
    if name.startswith(".") and name not in {".env.example"}:
        return True
    if name in LOCK_FILES:
        return True
    if name.endswith(".map") or name.endswith(".min.js") or name.endswith(".min.css"):
        return True
    return False


def iter_project_files(project: Path, exts: set[str] | None = None) -> Iterable[Path]:
    project = project.resolve()
    for root, dirs, files in os.walk(project):
        root_path = Path(root)
        dirs[:] = [d for d in dirs if not is_excluded(root_path / d)]
        for filename in files:
            path = root_path / filename
            if is_excluded(path):
                continue
            if exts is not None and path.suffix.lower() not in exts:
                continue
            yield path


def rel(path: Path, root: Path) -> str:
    return path.resolve().relative_to(root.resolve()).as_posix()


def read_text(path: Path, limit: int | None = None) -> str:
    data = path.read_bytes()
    if limit is not None:
        data = data[:limit]
    for encoding in ("utf-8", "utf-8-sig", "gb18030", "latin-1"):
        try:
            return data.decode(encoding)
        except UnicodeDecodeError:
            continue
    return data.decode("utf-8", errors="replace")


def read_json(path: Path) -> dict[str, Any]:
    return json.loads(read_text(path))


def write_json(path: Path, data: Any) -> None:
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(json.dumps(data, ensure_ascii=False, indent=2), encoding="utf-8")


def count_text_lines(path: Path) -> int:
    try:
        text = read_text(path)
    except Exception:
        return 0
    if not text:
        return 0
    return len(text.splitlines())


def looks_binary(path: Path) -> bool:
    try:
        chunk = path.read_bytes()[:4096]
    except Exception:
        return True
    return b"\x00" in chunk


def normalize_title(value: str) -> str:
    value = re.sub(r"[-_]+", " ", value).strip()
    value = re.sub(r"\s+", " ", value)
    return value or "待命名软件"


def safe_filename(value: str) -> str:
    value = re.sub(r'[\\/:*?"<>|]+', "_", value).strip()
    return value or "软件"


def ensure_dir(path: Path) -> Path:
    path.mkdir(parents=True, exist_ok=True)
    return path