#!/usr/bin/env python3
"""Exercise branded PWA responses from a running upstream WebUI server."""

from __future__ import annotations

import json
import sys
from collections.abc import Callable
from typing import Any
from urllib.parse import urljoin
from urllib.request import Request, urlopen


PNG_MAGIC = b"\x89PNG\r\n\x1a\n"
PERSONA_LINKS = (
    "static/hermes-agent.ico",
    "static/hermes-agent-192.png",
    "static/hermes-agent-512.png",
)


def _get(
    url: str,
    opener: Callable[..., Any],
) -> tuple[bytes, str]:
    request = Request(url, headers={"Accept-Encoding": "identity"})
    with opener(request, timeout=5) as response:
        status = int(getattr(response, "status", 0))
        if status != 200:
            raise RuntimeError(f"GET {url} returned HTTP {status}")
        body = response.read()
        final_url = response.geturl()
    return body, final_url


def _icon_sources(value: object) -> list[str]:
    sources: list[str] = []
    if isinstance(value, dict):
        icons = value.get("icons")
        if isinstance(icons, list):
            for icon in icons:
                if not isinstance(icon, dict) or not isinstance(icon.get("src"), str):
                    raise RuntimeError("manifest contains an invalid icon entry")
                if icon.get("type") != "image/png":
                    raise RuntimeError("manifest contains a non-PNG icon")
                sources.append(icon["src"])
        for child in value.values():
            if child is not icons:
                sources.extend(_icon_sources(child))
    elif isinstance(value, list):
        for child in value:
            sources.extend(_icon_sources(child))
    return sources


def smoke(
    base_url: str,
    *,
    opener: Callable[..., Any] = urlopen,
) -> dict[str, object]:
    base_url = base_url.rstrip("/") + "/"
    manifest_body, manifest_url = _get(urljoin(base_url, "manifest.json"), opener)
    try:
        manifest = json.loads(manifest_body)
    except (UnicodeDecodeError, json.JSONDecodeError) as exc:
        raise RuntimeError("served /manifest.json is not valid branded JSON") from exc

    if manifest.get("name") != "Hermes Chat" or manifest.get("short_name") != "Hermes":
        raise RuntimeError("served /manifest.json is not branded for Hermes Chat")
    expected = {
        "static/hermes-agent-192.png",
        "static/hermes-agent-512.png",
    }
    top_level = manifest.get("icons")
    if not isinstance(top_level, list) or {
        icon.get("src") for icon in top_level if isinstance(icon, dict)
    } != expected:
        raise RuntimeError("served /manifest.json has the wrong Hermes icons")

    icon_sources = _icon_sources(manifest)
    if not icon_sources:
        raise RuntimeError("served /manifest.json has no icon URLs")
    for source in icon_sources:
        icon_body, _icon_url = _get(urljoin(manifest_url, source), opener)
        if not icon_body.startswith(PNG_MAGIC):
            raise RuntimeError(f"manifest icon is not PNG: {source}")

    root_body, _root_url = _get(base_url, opener)
    try:
        root_html = root_body.decode("utf-8")
    except UnicodeDecodeError as exc:
        raise RuntimeError("served / is not UTF-8 HTML") from exc
    for source in PERSONA_LINKS:
        if source not in root_html:
            raise RuntimeError(f"served / omitted Hermes persona link: {source}")
    if "static/hermes-brand.css" not in root_html:
        raise RuntimeError("served / omitted static/hermes-brand.css")

    direct_icon, _direct_url = _get(
        urljoin(base_url, "static/hermes-agent-192.png"), opener
    )
    if not direct_icon.startswith(PNG_MAGIC):
        raise RuntimeError("served /static/hermes-agent-192.png is not PNG")

    return {
        "manifest": manifest_url,
        "icon_requests": len(icon_sources),
        "root": base_url,
        "direct_icon": "static/hermes-agent-192.png",
    }


def main() -> int:
    if len(sys.argv) != 2:
        raise SystemExit("usage: hermes-webui-smoke.py BASE_URL")
    result = smoke(sys.argv[1])
    print(
        "Hermes WebUI smoke passed: "
        f"manifest={result['manifest']} "
        f"icon_requests={result['icon_requests']} "
        "root=branded direct_icon=png"
    )
    return 0


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