#!/usr/bin/env python3
"""scripts/setup.py

Unified project setup helper (Python-only).

This script installs Python dependencies from `requirements.txt` and then
downloads Playwright browser binaries by running `python -m playwright install`.
By default this script installs **Chromium** only to conserve space; pass
`--browsers all` to install all supported engines (chromium, firefox, webkit).

When invoked without any arguments, `setup.py` will automatically select and
run the platform-specific bootstrap helper (`scripts/bootstrap.ps1` on Windows
or `scripts/bootstrap.sh` on POSIX) in **non-interactive (quiet)** mode so a
single `python ./scripts/setup.py` call does the usual bootstrap on your OS.

Usage:
  python ./scripts/setup.py           # install deps and playwright browsers (or run platform bootstrap if no args)
  python ./scripts/setup.py --skip-deps
  python ./scripts/setup.py --playwright-only

Optional flags:
  --skip-deps        Skip `pip install -r requirements.txt` step
  --no-playwright    Skip running `python -m playwright install` (still installs deps)
  --playwright-only  Install only Playwright browsers (installs playwright package if missing)
  --browsers         Comma-separated list of Playwright browsers to install (default: chromium)
  --install-editable Install the project in editable mode (pip install -e .) for running tests
  --install-deno     Install the Deno runtime using the official installer
  --deno-version     Pin a specific Deno version to install (e.g., v1.34.3)
  --upgrade-pip      Upgrade pip, setuptools, and wheel before installing deps
"""

from __future__ import annotations

import argparse
import subprocess
import sys
from pathlib import Path
import platform
import shutil
import os
import time


def run(cmd: list[str]) -> None:
    print(f"> {' '.join(cmd)}")
    subprocess.check_call(cmd)


# Helpers to find shell executables and to run the platform-specific
# bootstrap script (scripts/bootstrap.sh or scripts/bootstrap.ps1).
def _find_powershell() -> str | None:
    for name in ("pwsh", "powershell"):
        p = shutil.which(name)
        if p:
            return p
    return None


def _find_shell() -> str | None:
    for name in ("bash", "sh"):
        p = shutil.which(name)
        if p:
            return p
    return None


def run_platform_bootstrap(repo_root: Path) -> int:
    """Run the platform bootstrap script in quiet/non-interactive mode if present.

    Returns the script exit code (0 on success). If no script is present this is a
    no-op and returns 0.
    """
    ps1 = repo_root / "scripts" / "bootstrap.ps1"
    sh_script = repo_root / "scripts" / "bootstrap.sh"

    system = platform.system().lower()

    if system == "windows" and ps1.exists():
        exe = _find_powershell()
        if not exe:
            print("PowerShell not found; cannot run bootstrap.ps1", file=sys.stderr)
            return 1
        cmd = [exe, "-NoProfile", "-NonInteractive", "-ExecutionPolicy", "Bypass", "-File", str(ps1), "-Quiet"]
    elif sh_script.exists():
        shell = _find_shell()
        if not shell:
            print("Shell not found; cannot run bootstrap.sh", file=sys.stderr)
            return 1
        # Use -q (quiet) to skip interactive prompts when supported.
        cmd = [shell, str(sh_script), "-q"]
    else:
        # Nothing to run
        return 0

    print("Running platform bootstrap script:", " ".join(cmd))
    rc = subprocess.run(cmd, cwd=str(repo_root))
    if rc.returncode != 0:
        print(f"Bootstrap script failed with exit code {rc.returncode}", file=sys.stderr)
    return int(rc.returncode or 0)


def playwright_package_installed() -> bool:
    try:
        import playwright  # type: ignore

        return True
    except Exception:
        return False


def _build_playwright_install_cmd(browsers: str | None) -> list[str]:
    """Return the command to install Playwright browsers.

    - If browsers is None or empty: default to install Chromium only.
    - If browsers contains 'all': install all engines by running 'playwright install' with no extra args.
    - Otherwise, validate entries and return a command that installs the named engines.
    """
    base = [sys.executable, "-m", "playwright", "install"]
    if not browsers:
        return base + ["chromium"]

    items = [b.strip().lower() for b in browsers.split(",") if b.strip()]
    if not items:
        return base + ["chromium"]
    if "all" in items:
        return base

    allowed = {"chromium", "firefox", "webkit"}
    invalid = [b for b in items if b not in allowed]
    if invalid:
        raise ValueError(f"invalid browsers specified: {invalid}. Valid choices: chromium, firefox, webkit, or 'all'")
    return base + items


def _install_deno(version: str | None = None) -> int:
    """Install Deno runtime for the current platform.

    Uses the official Deno install scripts:
      - Unix/macOS: curl -fsSL https://deno.land/x/install/install.sh | sh [-s <version>]
      - Windows: powershell iwr https://deno.land/x/install/install.ps1 -useb | iex; Install-Deno [-Version <version>]

    Returns exit code 0 on success, non-zero otherwise.
    """
    system = platform.system().lower()

    try:
        if system == "windows":
            # Use official PowerShell installer
            if version:
                ver = version if version.startswith("v") else f"v{version}"
                ps_cmd = f"iwr https://deno.land/x/install/install.ps1 -useb | iex; Install-Deno -Version {ver}"
            else:
                ps_cmd = "iwr https://deno.land/x/install/install.ps1 -useb | iex"
            run(["powershell", "-NoProfile", "-ExecutionPolicy", "Bypass", "-Command", ps_cmd])
        else:
            # POSIX: use curl + sh installer
            if version:
                ver = version if version.startswith("v") else f"v{version}"
                cmd = f"curl -fsSL https://deno.land/x/install/install.sh | sh -s {ver}"
            else:
                cmd = "curl -fsSL https://deno.land/x/install/install.sh | sh"
            run(["sh", "-c", cmd])

        # Check that 'deno' is now available in PATH
        if shutil.which("deno"):
            print(f"Deno installed at: {shutil.which('deno')}")
            return 0
        else:
            print("Deno installation completed but 'deno' not found in PATH. You may need to add Deno's bin directory to your PATH manually.", file=sys.stderr)
            return 1
    except subprocess.CalledProcessError as exc:
        print(f"Deno install failed: {exc}", file=sys.stderr)
        return int(exc.returncode or 1)


def main() -> int:
    parser = argparse.ArgumentParser(description="Setup Medios-Macina: install deps and Playwright browsers")
    parser.add_argument("--skip-deps", action="store_true", help="Skip installing Python dependencies from requirements.txt")
    parser.add_argument("--no-playwright", action="store_true", help="Skip running 'playwright install' (only install packages)")
    parser.add_argument("--playwright-only", action="store_true", help="Only run 'playwright install' (skips dependency installation)")
    parser.add_argument("--browsers", type=str, default="chromium", help="Comma-separated list of browsers to install: chromium,firefox,webkit or 'all' (default: chromium)")
    parser.add_argument("--install-editable", action="store_true", help="Install the project in editable mode (pip install -e .) for running tests")
    deno_group = parser.add_mutually_exclusive_group()
    deno_group.add_argument("--install-deno", action="store_true", help="Install the Deno runtime (default behavior; kept for explicitness)")
    deno_group.add_argument("--no-deno", action="store_true", help="Skip installing Deno runtime (opt out)")
    parser.add_argument("--deno-version", type=str, default=None, help="Specific Deno version to install (e.g., v1.34.3)")
    parser.add_argument("--upgrade-pip", action="store_true", help="Upgrade pip/setuptools/wheel before installing requirements")
    args = parser.parse_args()

    repo_root = Path(__file__).resolve().parent.parent

    # If invoked without any arguments, prefer to delegate to the platform
    # bootstrap script (if present). The bootstrap scripts support a quiet/
    # non-interactive mode, which we use so "python ./scripts/setup.py" just
    # does the right thing on Windows and *nix without extra flags.
    if len(sys.argv) == 1:
        rc = run_platform_bootstrap(repo_root)
        if rc != 0:
            return rc
        print("Platform bootstrap completed successfully.")
        return 0

    if sys.version_info < (3, 8):
        print("Warning: Python 3.8+ is recommended.", file=sys.stderr)

    # Opinionated: always create or use a local venv at the project root (.venv)
    venv_dir = repo_root / ".venv"

    def _venv_python(p: Path) -> Path:
        if platform.system().lower() == "windows":
            return p / "Scripts" / "python.exe"
        return p / "bin" / "python"

    def _ensure_local_venv() -> Path:
        """Create (if missing) and return the path to the venv's python executable.

        This is intentionally opinionated: we keep a venv at `./.venv` in the repo root
        and use that for all package operations to keep developer environments reproducible.
        """
        try:
            if not venv_dir.exists():
                print(f"Creating local virtualenv at: {venv_dir}")
                run([sys.executable, "-m", "venv", str(venv_dir)])
            else:
                print(f"Using existing virtualenv at: {venv_dir}")

            py = _venv_python(venv_dir)
            if not py.exists():
                # Try recreating venv if python is missing
                print(f"Local venv python not found at {py}; recreating venv")
                run([sys.executable, "-m", "venv", str(venv_dir)])
            py = _venv_python(venv_dir)
            if not py.exists():
                raise RuntimeError(f"Unable to locate venv python at {py}")
            return py
        except subprocess.CalledProcessError as exc:
            print(f"Failed to create or prepare local venv: {exc}", file=sys.stderr)
            raise

    # Ensure a local venv is present and use it for subsequent installs.
    venv_python = _ensure_local_venv()
    print(f"Using venv python: {venv_python}")

    # Enforce opinionated behavior: install deps, playwright, deno, and install project in editable mode.
    # Ignore `--skip-deps` and `--install-editable` flags to keep the setup deterministic.
    args.skip_deps = False
    args.install_editable = True
    args.no_playwright = False

    try:
        if args.playwright_only:
            if not playwright_package_installed():
                print("'playwright' package not found; installing it via pip...")
                run([sys.executable, "-m", "pip", "install", "playwright"])

            print("Installing Playwright browsers (this may download several hundred MB)...")
            try:
                cmd = _build_playwright_install_cmd(args.browsers)
            except ValueError as exc:
                print(f"Error: {exc}", file=sys.stderr)
                return 2

            run(cmd)
            print("Playwright browsers installed successfully.")
            return 0

        if args.upgrade_pip:
            print("Upgrading pip, setuptools, and wheel in local venv...")
            run([str(venv_python), "-m", "pip", "install", "--upgrade", "pip", "setuptools", "wheel"])

        if not args.skip_deps:
            req_file = repo_root / "requirements.txt"
            if not req_file.exists():
                print(f"requirements.txt not found at {req_file}; skipping dependency installation.", file=sys.stderr)
            else:
                print(f"Installing Python dependencies into local venv from {req_file}...")
                run([str(venv_python), "-m", "pip", "install", "-r", str(req_file)])

        if not args.no_playwright:
            if not playwright_package_installed():
                print("'playwright' package not installed in venv; installing it...")
                run([str(venv_python), "-m", "pip", "install", "playwright"])

            print("Installing Playwright browsers (this may download several hundred MB)...")
            try:
                cmd = _build_playwright_install_cmd(args.browsers)
            except ValueError as exc:
                print(f"Error: {exc}", file=sys.stderr)
                return 2

            # Run Playwright install using the venv's python so binaries are available in venv
            cmd[0] = str(venv_python)
            run(cmd)

        # Optional: install the project in editable mode so tests can import the package
        # Install the project into the local venv (editable mode is the default, opinionated)
        print("Installing project into local venv (editable mode)")
        run([str(venv_python), "-m", "pip", "install", "-e", "."])

        # Verify top-level 'CLI' import and, if missing, attempt to make it available
        print("Verifying top-level 'CLI' import in venv...")
        try:
            import subprocess as _sub
            rc = _sub.run([str(venv_python), "-c", "import importlib; importlib.import_module('CLI')"], check=False)
            if rc.returncode == 0:
                print("OK: top-level 'CLI' is importable in the venv.")
            else:
                print("Top-level 'CLI' not importable; attempting to add repo path to venv site-packages via a .pth file...")
                cmd = [str(venv_python), "-c", (
                    "import site, sysconfig\n"
                    "out=[]\n"
                    "try:\n    out.extend(site.getsitepackages())\nexcept Exception:\n    pass\n"
                    "try:\n    p = sysconfig.get_paths().get('purelib')\n    if p:\n        out.append(p)\nexcept Exception:\n    pass\n"
                    "seen=[]; res=[]\n"
                    "for x in out:\n    if x and x not in seen:\n        seen.append(x); res.append(x)\n"
                    "for s in res:\n    print(s)\n"
                )]
                out = _sub.check_output(cmd, text=True).strip().splitlines()
                site_dir = None
                for sp in out:
                    if sp and Path(sp).exists():
                        site_dir = Path(sp)
                        break
                if site_dir is None:
                    print("Could not determine venv site-packages directory; skipping .pth fallback")
                else:
                    pth_file = site_dir / "medeia_repo.pth"
                    if pth_file.exists():
                        txt = pth_file.read_text(encoding="utf-8")
                        if str(repo_root) in txt:
                            print(f".pth already contains repo root: {pth_file}")
                        else:
                            with pth_file.open("a", encoding="utf-8") as fh:
                                fh.write(str(repo_root) + "\n")
                            print(f"Appended repo root to existing .pth: {pth_file}")
                    else:
                        with pth_file.open("w", encoding="utf-8") as fh:
                            fh.write(str(repo_root) + "\n")
                        print(f"Wrote .pth adding repo root to venv site-packages: {pth_file}")

                    # Re-check whether CLI can be imported now
                    rc2 = _sub.run([str(venv_python), "-c", "import importlib; importlib.import_module('CLI')"], check=False)
                    if rc2.returncode == 0:
                        print("Top-level 'CLI' import works after adding .pth")
                    else:
                        print("Adding .pth did not make top-level 'CLI' importable; consider creating an egg-link or checking the venv.")
        except Exception as exc:
            print(f"Warning: failed to verify or modify site-packages for top-level CLI: {exc}")

        # Optional: install Deno runtime (default: install unless --no-deno is passed)
        install_deno_requested = True
        if getattr(args, "no_deno", False):
            install_deno_requested = False
        elif getattr(args, "install_deno", False):
            install_deno_requested = True

        if install_deno_requested:
            print("Installing Deno runtime (local/system)...")
            rc = _install_deno(args.deno_version)
            if rc != 0:
                print("Deno installation failed.", file=sys.stderr)
                return rc

        # Write project-local launcher scripts (project root) that prefer the local .venv
        def _write_launchers():
            sh = repo_root / "mm"
            ps1 = repo_root / "mm.ps1"
            bat = repo_root / "mm.bat"

            sh_text = """#!/usr/bin/env bash
set -e
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
REPO="$SCRIPT_DIR"
VENV="$REPO/.venv"
# Make tools installed into the local venv available in PATH for provider discovery
export PATH="$VENV/bin:$PATH"
PY="$VENV/bin/python"
if [ -x "$PY" ]; then
  exec "$PY" -m medeia_macina.cli_entry "$@"
else
  exec python -m medeia_macina.cli_entry "$@"
fi
"""
            try:
                sh.write_text(sh_text, encoding="utf-8")
                sh.chmod(sh.stat().st_mode | 0o111)
            except Exception:
                pass

            ps1_text = r"""Param([Parameter(ValueFromRemainingArguments=$true)] $args)
$scriptDir = Split-Path -Parent $MyInvocation.MyCommand.Path
$repo = $scriptDir
$venv = Join-Path $repo '.venv'
# Ensure venv Scripts dir is on PATH for provider discovery
$venvScripts = Join-Path $venv 'Scripts'
if (Test-Path $venvScripts) { $env:PATH = $venvScripts + ';' + $env:PATH }
$py = Join-Path $venv 'Scripts\python.exe'
$cli = Join-Path $repo 'CLI.py'
if (Test-Path $py) { & $py -m medeia_macina.cli_entry @args; exit $LASTEXITCODE }
if (Test-Path $cli) { & python $cli @args; exit $LASTEXITCODE }
# fallback
python -m medeia_macina.cli_entry @args
"""
            try:
                ps1.write_text(ps1_text, encoding="utf-8")
            except Exception:
                pass

            bat_text = (
                "@echo off\r\n"
                "set SCRIPT_DIR=%~dp0\r\n"
                "set PATH=%SCRIPT_DIR%\.venv\Scripts;%PATH%\r\n"
                "if exist \"%SCRIPT_DIR%\\.venv\\Scripts\\python.exe\" \"%SCRIPT_DIR%\\.venv\\Scripts\\python.exe\" -m medeia_macina.cli_entry %*\r\n"
                "if exist \"%SCRIPT_DIR%\\CLI.py\" python \"%SCRIPT_DIR%\\CLI.py\" %*\r\n"
                "python -m medeia_macina.cli_entry %*\r\n"
            )
            try:
                bat.write_text(bat_text, encoding="utf-8")
            except Exception:
                pass

        _write_launchers()

        # Install user-global shims so `mm` can be executed from any shell session.
        def _install_user_shims(repo: Path) -> None:
            try:
                home = Path.home()
                system = platform.system().lower()

                if system == "windows":
                    user_bin = Path(os.environ.get("USERPROFILE", str(home))) / "bin"
                    user_bin.mkdir(parents=True, exist_ok=True)

                    # Write mm.cmd (CMD shim)
                    mm_cmd = user_bin / "mm.cmd"
                    cmd_text = (
                        f"@echo off\r\n"
                        f"set REPO={repo}\r\n"
                        f"if exist \"%REPO%\\.venv\\Scripts\\mm.exe\" \"%REPO%\\.venv\\Scripts\\mm.exe\" %*\r\n"
                        f"if defined MM_DEBUG (\r\n"
                        f"  echo MM_DEBUG: REPO=%REPO%\r\n"
                        f"  if exist \"%REPO%\\.venv\\Scripts\\python.exe\" \"%REPO%\\.venv\\Scripts\\python.exe\" -c \"import sys,importlib,importlib.util; print('sys.executable:', sys.executable); print('sys.path (first 8):', sys.path[:8]);\" \r\n"
                        f")\r\n"
                        f"if exist \"%REPO%\\.venv\\Scripts\\python.exe\" \"%REPO%\\.venv\\Scripts\\python.exe\" -m medeia_macina.cli_entry %*\r\n"
                        f"python -m medeia_macina.cli_entry %*\r\n"
                    )
                    if mm_cmd.exists():
                        bak = mm_cmd.with_suffix(f".bak{int(time.time())}")
                        mm_cmd.replace(bak)
                    mm_cmd.write_text(cmd_text, encoding="utf-8")

                    # Write mm.ps1 (PowerShell shim)
                    mm_ps1 = user_bin / "mm.ps1"
                    ps1_text = (
                        "Param([Parameter(ValueFromRemainingArguments=$true)] $args)\n"
                        f"$repo = \"{repo}\"\n"
                        "$venv = Join-Path $repo '.venv'\n"
                        "$exe = Join-Path $venv 'Scripts\\mm.exe'\n"
                        "if (Test-Path $exe) { & $exe @args; exit $LASTEXITCODE }\n"
                        "$py = Join-Path $venv 'Scripts\\python.exe'\n"
                        "if (Test-Path $py) {\n"
                        "  if ($env:MM_DEBUG) {\n"
                        "    Write-Host \"MM_DEBUG: diagnostics\" -ForegroundColor Yellow\n"
                        "    & $py -c \"import sys,importlib,importlib.util,traceback; print('sys.executable:', sys.executable); print('sys.path (first 8):', sys.path[:8]);\"\n"
                        "  }\n"
                        "  & $py -m medeia_macina.cli_entry @args; exit $LASTEXITCODE\n"
                        "}\n"
                        "python -m medeia_macina.cli_entry @args\n"
                    )
                    if mm_ps1.exists():
                        bak = mm_ps1.with_suffix(f".bak{int(time.time())}")
                        mm_ps1.replace(bak)
                    mm_ps1.write_text(ps1_text, encoding="utf-8")

                    # Attempt to add user_bin to the user's PATH if it's not present.
                    try:
                        cur = os.environ.get("PATH", "")
                        str_bin = str(user_bin)
                        if str_bin not in cur:
                            ps_cmd = (
                                "$bin = '{bin}';"
                                "$cur = [Environment]::GetEnvironmentVariable('PATH','User');"
                                "if ($cur -notlike \"*$bin*\") {[Environment]::SetEnvironmentVariable('PATH', ($bin + ';' + ($cur -ne $null ? $cur : '')), 'User')}"
                            ).format(bin=str_bin.replace('\\','\\\\'))
                            subprocess.run(["powershell","-NoProfile","-Command", ps_cmd], check=False)
                    except Exception:
                        pass

                    print(f"Installed global launchers to: {user_bin}")

                else:
                    # POSIX
                    user_bin = Path(os.environ.get("XDG_BIN_HOME", str(home / ".local/bin")))
                    user_bin.mkdir(parents=True, exist_ok=True)

                    mm_sh = user_bin / "mm"
                    sh_text = (
                        "#!/usr/bin/env bash\n"
                        "set -e\n"
                        f"REPO=\"{repo}\"\n"
                        "# Prefer git top-level when available to avoid embedding a parent path.\n"
                        "if command -v git >/dev/null 2>&1; then\n"
                        "  gitroot=$(git -C \"$REPO\" rev-parse --show-toplevel 2>/dev/null || true)\n"
                        "  if [ -n \"$gitroot\" ]; then\n"
                        "    REPO=\"$gitroot\"\n"
                        "  fi\n"
                        "fi\n"
                        "# If git not available or didn't resolve, walk up from CWD to find a project root.\n"
                        "if [ ! -f \"$REPO/CLI.py\" ] && [ ! -f \"$REPO/pyproject.toml\" ]; then\n"
                        "  CUR=\"$(pwd -P)\"\n"
                        "  while [ \"$CUR\" != \"/\" ] && [ \"$CUR\" != \"\" ]; do\n"
                        "    if [ -f \"$CUR/CLI.py\" ] || [ -f \"$CUR/pyproject.toml\" ]; then\n"
                        "      REPO=\"$CUR\"\n"
                        "      break\n"
                        "    fi\n"
                        "    CUR=\"$(dirname \"$CUR\")\"\n"
                        "  done\n"
                        "fi\n"
                        "VENV=\"$REPO/.venv\"\n"
                        "# Debug mode: set MM_DEBUG=1 to print repository, venv, and import diagnostics\n"
                        "if [ -n \"${MM_DEBUG:-}\" ]; then\n"
                        "  echo \"MM_DEBUG: diagnostics\" >&2\n"
                        "  echo \"Resolved REPO: $REPO\" >&2\n"
                        "  echo \"Resolved VENV: $VENV\" >&2\n"
                        "  echo \"VENV exists: $( [ -d \"$VENV\" ] && echo yes || echo no )\" >&2\n"
                        "  echo \"Candidates:\" >&2\n"
                        "  echo \"  VENV/bin/mm: $( [ -x \"$VENV/bin/mm\" ] && echo yes || echo no )\" >&2\n"
                        "  echo \"  VENV/bin/python3: $( [ -x \"$VENV/bin/python3\" ] && echo yes || echo no )\" >&2\n"
                        "  echo \"  VENV/bin/python: $( [ -x \"$VENV/bin/python\" ] && echo yes || echo no )\" >&2\n"
                        "  echo \"  system python3: $(command -v python3 || echo none)\" >&2\n"
                        "  echo \"  system python: $(command -v python || echo none)\" >&2\n"
                        "  for pycmd in \"$VENV/bin/python3\" \"$VENV/bin/python\" \"$(command -v python3 2>/dev/null)\" \"$(command -v python 2>/dev/null)\"; do\n"
                        "    if [ -n \"$pycmd\" ] && [ -x \"$pycmd\" ]; then\n"
                        "      echo \"---- Testing with: $pycmd ----\" >&2\n"
                        "      $pycmd - <<'PY'\nimport sys, importlib, traceback, importlib.util\nprint('sys.executable:', sys.executable)\nprint('sys.path (first 8):', sys.path[:8])\nfor mod in ('CLI','medeia_macina','medeia_macina.cli_entry'):\n    try:\n        spec = importlib.util.find_spec(mod)\n        print(mod, 'spec:', spec)\n        if spec:\n            m = importlib.import_module(mod)\n            print(mod, 'loaded at', getattr(m, '__file__', None))\n    except Exception:\n        print(mod, 'import failed')\n        traceback.print_exc()\nPY\n"
                        "    fi\n"
                        "  done\n"
                        "  echo \"MM_DEBUG: end diagnostics\" >&2\n"
                        "fi\n"
                        "# Packaged console script in the venv if available\n"
                        "if [ -x \"$VENV/bin/mm\" ]; then\n"
                        "  exec \"$VENV/bin/mm\" \"$@\"\n"
                        "fi\n"
                        "# Prefer venv's python3, then venv's python\n"
                        "if [ -x \"$VENV/bin/python3\" ]; then\n"
                        "  exec \"$VENV/bin/python3\" -m medeia_macina.cli_entry \"$@\"\n"
                        "fi\n"
                        "if [ -x \"$VENV/bin/python\" ]; then\n"
                        "  exec \"$VENV/bin/python\" -m medeia_macina.cli_entry \"$@\"\n"
                        "fi\n"
                        "# Fallback to system python3, then system python (only if it's Python 3)\n"
                        "if command -v python3 >/dev/null 2>&1; then\n"
                        "  exec python3 -m medeia_macina.cli_entry \"$@\"\n"
                        "fi\n"
                        "if command -v python >/dev/null 2>&1; then\n"
                        "  if python -c 'import sys; sys.exit(0 if sys.version_info[0] >= 3 else 1)'; then\n"
                        "    exec python -m medeia_macina.cli_entry \"$@\"\n"
                        "  fi\n"
                        "fi\n"
                        "echo 'Error: no suitable Python 3 interpreter found. Please install Python 3 or use the venv.' >&2\n"
                        "exit 127\n"
                    )
                    if mm_sh.exists():
                        bak = mm_sh.with_suffix(f".bak{int(time.time())}")
                        mm_sh.replace(bak)
                    mm_sh.write_text(sh_text, encoding="utf-8")
                    mm_sh.chmod(mm_sh.stat().st_mode | 0o111)

                    # Ensure the user's bin is on PATH for future sessions by adding to ~/.profile
                    cur_path = os.environ.get("PATH", "")
                    if str(user_bin) not in cur_path:
                        profile = home / ".profile"
                        snippet = (
                            "# Added by Medeia-Macina setup: ensure user local bin is on PATH\n"
                            "if [ -d \"$HOME/.local/bin\" ] && [[ \":$PATH:\" != *\":$HOME/.local/bin:\"* ]]; then\n"
                            "  PATH=\"$HOME/.local/bin:$PATH\"\n"
                            "fi\n"
                        )
                        try:
                            txt = profile.read_text() if profile.exists() else ""
                            if snippet.strip() not in txt:
                                with profile.open("a", encoding="utf-8") as fh:
                                    fh.write("\n" + snippet)
                        except Exception:
                            pass

                    print(f"Installed global launcher to: {mm_sh}")

            except Exception as exc:  # pragma: no cover - best effort
                print(f"Failed to install global shims: {exc}", file=sys.stderr)

        _install_user_shims(repo_root)

        print("Setup complete.")
        return 0

    except subprocess.CalledProcessError as exc:
        print(f"Error: command failed with exit {exc.returncode}: {exc}", file=sys.stderr)
        return int(exc.returncode or 1)
    except Exception as exc:  # pragma: no cover - defensive
        print(f"Unexpected error: {exc}", file=sys.stderr)
        return 2


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