"""
Example workflow integrating agent-permissions with Selenium.

Prerequisites:
    pip install selenium agent-permissions
    # And ensure the appropriate WebDriver binary is on PATH.
"""

from __future__ import annotations

from lxml import html

from agent_permissions import discover_manifest, validate_interaction


def validate_click(manifest_wrapper, selector: str) -> bool:
    """Helper to check whether a click is allowed."""

    if manifest_wrapper is None or manifest_wrapper.manifest is None:
        return False

    dom = html.fromstring(manifest_wrapper.details.get("html", ""))
    matches = dom.cssselect(selector)
    if not matches:
        return False

    result = validate_interaction(
        manifest_wrapper.manifest,
        verb="click_element",
        element=matches[0],
    )
    return result.allowed


def main() -> None:
    try:
        from selenium import webdriver
        from selenium.webdriver.common.by import By
    except ImportError:  # pragma: no cover - sample only
        raise SystemExit("Install selenium to run this example: pip install selenium")

    driver = webdriver.Chrome()
    driver.get("https://example.com/products")

    manifest_wrapper = discover_manifest(
        driver.current_url,
        html=driver.page_source,
    )
    if manifest_wrapper is not None:
        manifest_wrapper.details.setdefault("html", driver.page_source)

    if validate_click(manifest_wrapper, "#buy"):
        driver.find_element(By.CSS_SELECTOR, "#buy").click()
        print("Clicked buy button in compliance with manifest.")
    else:
        print("Click denied by manifest or manifest missing.")

    driver.quit()


if __name__ == "__main__":
    main()