"""读 ~/skills_env.md 里的本机路径（KICAD_ROOT 等），不在脚本里写死。"""
import io
import os
import re

_ENV = None


def env(key, default=None):
    global _ENV
    if _ENV is None:
        _ENV = {}
        p = os.path.join(os.path.expanduser("~"), "skills_env.md")
        if os.path.exists(p):
            for line in io.open(p, encoding="utf-8", errors="replace"):
                m = re.match(r"^\s*([A-Z0-9_]+)\s*=\s*(.+?)\s*$", line)
                if m:
                    _ENV.setdefault(m.group(1), re.split(r"\s+#", m.group(2))[0].strip())
    return os.environ.get(key) or _ENV.get(key) or default


def kicad_root():
    r = env("KICAD_ROOT")
    if not r:
        raise SystemExit("~/skills_env.md 里没有 KICAD_ROOT")
    return r


def kicad_cli():
    return os.path.join(kicad_root(), "bin", "kicad-cli.exe")


def kicad_symbol_dir():
    return os.path.join(kicad_root(), "share", "kicad", "symbols")


def kicad_footprint_dir():
    return os.path.join(kicad_root(), "share", "kicad", "footprints")


def chrome():
    """headless 渲染框图用。skills_env 里可配 CHROME_EXE；否则按常见位置找 Chrome / Edge。"""
    c = env("CHROME_EXE")
    cands = [c] if c else []
    cands += [r"C:\Program Files\Google\Chrome\Application\chrome.exe",
              r"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe",
              r"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe",
              r"C:\Program Files\Microsoft\Edge\Application\msedge.exe"]
    for p in cands:
        if p and os.path.exists(p):
            return p
    raise SystemExit("找不到 Chrome/Edge，请在 ~/skills_env.md 里配 CHROME_EXE")