import logging

import httpx

logger = logging.getLogger(__name__)

MENU_MAX_TOP_LEVEL = 3
MENU_MAX_SUB_LEVEL = 5
MENU_TITLE_MAX_CHARS = 30
MENU_PAYLOAD_MAX_CHARS = 1000


def _build_menu_api_url(api_version: str = "v24.0") -> str:
    return f"https://graph.facebook.com/{api_version}/me/messenger_profile"


def _compute_appsecret_proof(access_token: str, app_secret: str) -> str:
    import hashlib
    import hmac

    return hmac.new(
        app_secret.encode("utf-8"),
        access_token.encode("utf-8"),
        hashlib.sha256,
    ).hexdigest()


async def set_persistent_menu(
    access_token: str,
    menu_items: list[dict],
    *,
    app_secret: str = "",
    api_version: str = "v24.0",
    composer_input_disabled: bool = False,
) -> dict:
    url = _build_menu_api_url(api_version)
    params: dict = {"access_token": access_token}
    if app_secret:
        params["appsecret_proof"] = _compute_appsecret_proof(access_token, app_secret)

    payload = {
        "persistent_menu": [
            {
                "locale": "default",
                "composer_input_disabled": composer_input_disabled,
                "call_to_actions": menu_items,
            }
        ]
    }

    async with httpx.AsyncClient(timeout=15.0) as client:
        try:
            resp = await client.post(url, json=payload, params=params)
            if resp.status_code == 200:
                logger.info("Persistent menu set successfully")
                return {"success": True, "data": resp.json()}
            logger.error("Failed to set persistent menu: %d %s", resp.status_code, resp.text[:200])
            return {"success": False, "error": resp.text[:200]}
        except httpx.RequestError as exc:
            logger.error("Persistent menu network error: %s", exc)
            return {"success": False, "error": str(exc)}


async def delete_persistent_menu(
    access_token: str,
    *,
    app_secret: str = "",
    api_version: str = "v24.0",
) -> dict:
    url = _build_menu_api_url(api_version)
    params: dict = {"access_token": access_token}
    if app_secret:
        params["appsecret_proof"] = _compute_appsecret_proof(access_token, app_secret)

    payload = {"fields": ["persistent_menu"]}

    async with httpx.AsyncClient(timeout=15.0) as client:
        try:
            resp = await client.delete(url, json=payload, params=params)
            if resp.status_code == 200:
                logger.info("Persistent menu deleted successfully")
                return {"success": True, "data": resp.json()}
            logger.error("Failed to delete persistent menu: %d %s", resp.status_code, resp.text[:200])
            return {"success": False, "error": resp.text[:200]}
        except httpx.RequestError as exc:
            logger.error("Persistent menu delete network error: %s", exc)
            return {"success": False, "error": str(exc)}


async def get_persistent_menu(
    access_token: str,
    *,
    app_secret: str = "",
    api_version: str = "v24.0",
) -> dict:
    url = _build_menu_api_url(api_version)
    params: dict = {
        "access_token": access_token,
        "fields": "persistent_menu",
    }
    if app_secret:
        params["appsecret_proof"] = _compute_appsecret_proof(access_token, app_secret)

    async with httpx.AsyncClient(timeout=15.0) as client:
        try:
            resp = await client.get(url, params=params)
            if resp.status_code == 200:
                data = resp.json()
                return {"success": True, "data": data.get("data", [])}
            logger.error("Failed to get persistent menu: %d %s", resp.status_code, resp.text[:200])
            return {"success": False, "error": resp.text[:200]}
        except httpx.RequestError as exc:
            logger.error("Persistent menu get network error: %s", exc)
            return {"success": False, "error": str(exc)}