from __future__ import annotations

from typing import Any

from fastapi import Request

from app.config import Settings


def build_agent_card(settings: Settings, request: Request) -> dict[str, Any]:
    base_url = _resolve_base_url(settings=settings, request=request)
    return {
        "name": settings.a2a_agent_name,
        "description": settings.a2a_agent_description,
        "url": f"{base_url}/a2a/rpc",
        "version": "0.1.0",
        "protocolVersion": "1.0",
        "defaultInputModes": ["application/json"],
        "defaultOutputModes": ["application/json"],
        "capabilities": {
            "streaming": False,
            "pushNotifications": False,
            "stateTransitionHistory": False,
        },
        "securitySchemes": {
            "bearerAuth": {
                "type": "http",
                "scheme": "bearer",
                "description": "Use the same Bearer/API key auth as the REST API.",
            }
        },
        "security": [{"bearerAuth": []}],
        "skills": [
            {
                "id": "availability.query",
                "name": "Check Availability",
                "description": "Checks Google Calendar availability for a given time range.",
                "tags": ["calendar", "availability", "scheduling"],
                "examples": [
                    "SendMessage with params.start/end/calendar_ids to check free/busy for a time window."
                ],
                "inputModes": ["application/json"],
                "outputModes": ["application/json"],
            }
        ],
    }


def _resolve_base_url(*, settings: Settings, request: Request) -> str:
    if settings.a2a_public_base_url:
        return settings.a2a_public_base_url.rstrip("/")
    return str(request.base_url).rstrip("/")