from __future__ import annotations
from pathlib import Path
import shutil, subprocess, sys, re

ROOT = Path(__file__).resolve().parents[2]  # repo root

def say(msg: str) -> None:
    print(msg, flush=True)

def ensure_dir(p: Path) -> None:
    p.mkdir(parents=True, exist_ok=True)

def write_if_missing(path: Path, content: str) -> None:
    ensure_dir(path.parent)
    if not path.exists():
        path.write_text(content, encoding="utf-8")

def copy_if_exists(src: Path, dst: Path) -> None:
    if src.exists():
        ensure_dir(dst.parent)
        shutil.copy2(src, dst)
def copy_if_missing(src: Path, dst: Path) -> None:
    dst.parent.mkdir(parents=True, exist_ok=True)
    if not dst.exists():
        shutil.copy2(src, dst)
def run(cmd: list[str], cwd: Path | None = None) -> int:
    proc = subprocess.Popen(cmd, cwd=cwd, stdout=sys.stdout, stderr=sys.stderr)
    return proc.wait()

def read_version(version_file: Path | None = None) -> str:
    vf = version_file or (ROOT / "VERSION")
    return (vf.read_text(encoding="utf-8").strip() if vf.exists() else "0.0.0")

def write_version(new_version: str, version_file: Path | None = None) -> None:
    vf = version_file or (ROOT / "VERSION")
    vf.write_text(new_version.strip() + "\n", encoding="utf-8")

_semver = re.compile(r"^(\d+)\.(\d+)\.(\d+)$")
def bump_version(kind: str = "patch", version_file: Path | None = None) -> str:
    cur = read_version(version_file)
    m = _semver.match(cur) or _semver.match("0.1.0")  # default if missing
    major, minor, patch = map(int, m.groups())
    if kind == "major":
        major, minor, patch = major + 1, 0, 0
    elif kind == "minor":
        minor, patch = minor + 1, 0
    else:
        patch += 1
    new = f"{major}.{minor}.{patch}"
    write_version(new, version_file)
    return new

def bundle_path(version_file: Path | None = None) -> Path:
    """
    Return the install bundle path for the current VERSION (e.g., install/cascadingdev-0.1.2).
    Raises FileNotFoundError if missing.
    """
    ver = read_version(version_file)
    bp = ROOT / "install" / f"cascadingdev-{ver}"
    if not bp.exists():
        raise FileNotFoundError(f"Bundle not found: {bp}. Build it with `cascadingdev build`.")
    return bp