"""cow install-browser - Install Playwright + Chromium for the browser tool."""

import os
import sys
import subprocess

import click


def _has_display() -> bool:
    """Check if a graphical display is available (Linux only)."""
    return bool(os.environ.get("DISPLAY") or os.environ.get("WAYLAND_DISPLAY"))


def _is_headless_linux() -> bool:
    """True when running on a Linux server without a display."""
    return sys.platform == "linux" and not _has_display()


@click.command("install-browser")
def install_browser():
    """Install browser tool dependencies (Playwright + Chromium)."""
    python = sys.executable

    # Step 1: Install playwright package
    click.echo(click.style("[1/3] Installing playwright Python package...", fg="yellow"))
    ret = subprocess.call([python, "-m", "pip", "install", "playwright"])
    if ret != 0:
        click.echo(click.style("Failed to install playwright package.", fg="red"))
        raise SystemExit(1)
    click.echo(click.style("playwright package installed.", fg="green"))
    click.echo()

    # Step 2: System dependencies (Linux only)
    if sys.platform == "linux":
        click.echo(click.style("[2/3] Installing system dependencies (Linux)...", fg="yellow"))
        ret = subprocess.call([python, "-m", "playwright", "install-deps", "chromium"])
        if ret != 0:
            click.echo(click.style(
                "Could not auto-install system deps (may need sudo).\n"
                f"  Run manually: sudo {python} -m playwright install-deps chromium",
                fg="yellow",
            ))
    else:
        click.echo(click.style(f"[2/3] Skipping system deps (not needed on {sys.platform}).", fg="yellow"))
    click.echo()

    # Step 3: Install Chromium (headless shell on Linux servers, full elsewhere)
    click.echo(click.style("[3/3] Installing Chromium browser...", fg="yellow"))
    cmd = [python, "-m", "playwright", "install", "chromium"]
    if _is_headless_linux():
        cmd.append("--only-shell")
        click.echo("  (headless-only mode for Linux server)")
    elif sys.platform == "linux":
        click.echo("  (full browser for Linux desktop)")

    ret = subprocess.call(cmd)
    if ret != 0:
        click.echo(click.style("Failed to install Chromium.", fg="red"))
        raise SystemExit(1)

    click.echo()
    click.echo(click.style("Browser tool ready! Restart CowAgent to enable it.", fg="green"))