"""Self-management commands for bin."""

import os
import shutil
import subprocess
import sys
from pathlib import Path

import click


def _get_project_root() -> Path:
    """Get mytoolkit project root from source tree."""
    return Path(__file__).parent.parent.parent


def _run(cmd: list[str], cwd: Path | None = None, check: bool = True) -> None:
    result = subprocess.run(cmd, cwd=str(cwd) if cwd else None, check=False)
    if check and result.returncode != 0:
        raise click.Exit(result.returncode)


def _install(root: Path) -> None:
    """Install or update using the current Python's pip (editable)."""
    click.secho("Installing mytoolkit (editable)…", fg="cyan")
    _run([sys.executable, "-m", "pip", "install", "-e", str(root), "--upgrade"])

    entry_point = shutil.which("mytoolkit")
    if entry_point:
        click.secho(f"Entry point: {entry_point}", fg="green")
    else:
        click.secho("Warning: mytoolkit not found in PATH after install", fg="yellow")

    _install_completions()


def _install_completions() -> None:
    venv_toolkit = shutil.which("mytoolkit")
    if not venv_toolkit:
        click.secho("Warning: cannot generate completions (mytoolkit not in PATH)", fg="yellow")
        return

    comp_dir = Path.home() / ".local" / "bin" / "completions"
    comp_dir.mkdir(parents=True, exist_ok=True)
    shell = os.environ.get("SHELL", "")
    if "zsh" in shell:
        comp_file = comp_dir / "_mytoolkit"
        result = subprocess.run(
            [venv_toolkit],
            env={**os.environ, "_MYTOOLKIT_COMPLETE": "zsh_source"},
            capture_output=True,
            text=True,
        )
        if result.returncode == 0:
            comp_file.write_text(result.stdout)
            click.secho(f"Installed zsh completion: {comp_file}", fg="green")
        else:
            click.secho("Warning: failed to generate zsh completion", fg="yellow")
    elif "bash" in shell:
        comp_file = comp_dir / "mytoolkit.bash"
        result = subprocess.run(
            [venv_toolkit],
            env={**os.environ, "_MYTOOLKIT_COMPLETE": "bash_source"},
            capture_output=True,
            text=True,
        )
        if result.returncode == 0:
            comp_file.write_text(result.stdout)
            click.secho(f"Installed bash completion: {comp_file}", fg="green")
        else:
            click.secho("Warning: failed to generate bash completion", fg="yellow")


def _uninstall() -> None:
    click.secho("Uninstalling mytoolkit package…", fg="cyan")
    subprocess.run(
        [sys.executable, "-m", "pip", "uninstall", "mytoolkit", "-y"],
        check=False,
    )

    comp_dir = Path.home() / ".local" / "bin" / "completions"
    for f in (comp_dir / "_mytoolkit", comp_dir / "mytoolkit.bash"):
        if f.exists() or f.is_symlink():
            f.unlink()
            click.secho(f"Removed {f}", fg="green")


@click.command(name="update")
def update_cmd():
    """Update mytoolkit from the local repository."""
    root = _get_project_root()
    click.secho("Updating mytoolkit…", fg="cyan")
    _install(root)
    click.secho("mytoolkit updated.", fg="green")


@click.command(name="uninstall")
def uninstall_cmd():
    """Uninstall mytoolkit."""
    click.secho("Uninstalling mytoolkit…", fg="cyan")
    _uninstall()
    click.secho("mytoolkit removed.", fg="green")