"""Bring the browser to the front before clicking.

macOS (and Windows, to a lesser degree) treats a click on an unfocused window as
an activation gesture: the click raises the window and is swallowed there, never
reaching the control underneath. So an automated click against a background Chrome
does nothing at all the first time, then works on the second attempt — which looks
like a flaky clicker but is really the window manager doing its job.

The extension already calls chrome.windows.update({focused: true}), but that only
orders windows *within* Chrome. If the frontmost application is your terminal —
which it is, because that's where this script was launched — Chrome as a whole is
still in the background. This module raises the application itself.
"""

import subprocess
import sys
import time

# Chrome ships under several bundle ids; accept whichever is installed.
MAC_BUNDLES = (
    "com.google.Chrome",
    "com.google.Chrome.beta",
    "com.google.Chrome.dev",
    "com.google.Chrome.canary",
    "com.brave.Browser",
    "com.microsoft.edgemac",
)

SETTLE = 0.20   # let the window manager finish raising before measuring or clicking


class FocusResult:
    def __init__(self, ok: bool, detail: str):
        self.ok = ok
        self.detail = detail

    def __bool__(self) -> bool:
        return self.ok


def _mac_workspace():
    """NSWorkspace via pyobjc. Unlike AppleScript this needs no Automation
    permission — activating an app is not scripting it."""
    try:
        from AppKit import NSWorkspace
    except ImportError:
        return None
    return NSWorkspace.sharedWorkspace()


def frontmost() -> str | None:
    """Bundle id (macOS) or process name of the frontmost application."""
    if sys.platform == "darwin":
        ws = _mac_workspace()
        if ws is None:
            return None
        app = ws.frontmostApplication()
        return app.bundleIdentifier() if app else None
    return None


def _mac_activate() -> FocusResult:
    ws = _mac_workspace()
    if ws is None:
        # pyobjc's AppKit isn't present. osascript works but may prompt for
        # Automation permission the first time.
        try:
            subprocess.run(
                ["osascript", "-e", 'tell application "Google Chrome" to activate'],
                check=True, capture_output=True, timeout=5,
            )
            return FocusResult(True, "activated via osascript")
        except Exception as exc:
            return FocusResult(False, f"could not activate Chrome ({exc})")

    running = {a.bundleIdentifier(): a for a in ws.runningApplications()}
    for bundle in MAC_BUNDLES:
        app = running.get(bundle)
        if app is None:
            continue
        # NSApplicationActivateIgnoringOtherApps — take focus even though the
        # terminal currently owns it.
        app.activateWithOptions_(1 << 1)
        return FocusResult(True, f"activated {bundle}")

    return FocusResult(False, "no Chrome-family browser is running")


def _other_activate() -> FocusResult:
    """Windows/Linux: pyautogui already depends on pygetwindow, so use it."""
    try:
        import pygetwindow
    except ImportError:
        return FocusResult(False, "pygetwindow unavailable — cannot raise the browser")

    wins = [w for w in pygetwindow.getAllWindows()
            if w.title and "Chrome" in w.title and w.visible]
    if not wins:
        return FocusResult(False, "no Chrome window found")
    try:
        win = wins[0]
        if getattr(win, "isMinimized", False):
            win.restore()
        win.activate()
        return FocusResult(True, f"activated window {win.title[:40]!r}")
    except Exception as exc:
        return FocusResult(False, f"could not activate window ({exc})")


def activate_browser() -> FocusResult:
    """Raise the browser application above everything else."""
    result = _mac_activate() if sys.platform == "darwin" else _other_activate()
    if result.ok:
        time.sleep(SETTLE)
    return result


def ensure_frontmost(timeout: float = 1.5) -> FocusResult:
    """Raise the browser and, where we can check, confirm it actually came forward.

    Returning ok=False does not mean the click will fail — only that we could not
    verify. The caller decides whether to proceed.
    """
    result = activate_browser()
    if not result.ok:
        return result

    if sys.platform != "darwin":
        return result   # no cheap way to verify; activation call succeeded

    deadline = time.monotonic() + timeout
    while time.monotonic() < deadline:
        front = frontmost()
        if front is None:
            return FocusResult(True, result.detail + " (unverified)")
        if front in MAC_BUNDLES:
            return FocusResult(True, f"{front} is frontmost")
        time.sleep(0.05)

    return FocusResult(False, f"browser did not come to the front (frontmost is {frontmost()})")