"""App factory comune per i servizi mcp-{exchange}.

Centralizza il boilerplate dei `__main__.py`:
- configure_root_logging (JSON)
- fail_fast_if_missing su env mandatory
- summarize env
- load creds JSON
- resolve_environment con default URLs
- load token store
- delega creazione client + app a callback per-servizio
- uvicorn.run

Ogni servizio invoca `run_exchange_main(spec)` con uno spec dichiarativo.
"""
from __future__ import annotations

import json
import os
from collections.abc import Callable
from dataclasses import dataclass
from typing import Any

import uvicorn

from mcp_common.auth import load_token_store_from_files
from mcp_common.env_validation import fail_fast_if_missing, require_env, summarize
from mcp_common.environment import EnvironmentInfo, resolve_environment
from mcp_common.logging import configure_root_logging


@dataclass(frozen=True)
class ExchangeAppSpec:
    exchange: str
    creds_env_var: str
    env_var: str  # es. "BYBIT_TESTNET", "ALPACA_PAPER"
    flag_key: str  # campo nel secret JSON ("testnet" o "paper")
    default_base_url_live: str
    default_base_url_testnet: str
    default_port: int
    build_client: Callable[[dict, EnvironmentInfo], Any]
    build_app: Callable[..., Any]
    extra_summarize_envs: tuple[str, ...] = ()


def run_exchange_main(spec: ExchangeAppSpec) -> None:
    configure_root_logging()

    fail_fast_if_missing([spec.creds_env_var])
    summarize([
        spec.creds_env_var,
        "CORE_TOKEN_FILE",
        "OBSERVER_TOKEN_FILE",
        "PORT",
        "HOST",
        spec.env_var,
        *spec.extra_summarize_envs,
    ])

    creds_file = require_env(spec.creds_env_var, f"{spec.exchange} credentials JSON path")
    with open(creds_file) as f:
        creds = json.load(f)

    env_info = resolve_environment(
        creds,
        env_var=spec.env_var,
        flag_key=spec.flag_key,
        exchange=spec.exchange,
        default_base_url_live=spec.default_base_url_live,
        default_base_url_testnet=spec.default_base_url_testnet,
    )

    client = spec.build_client(creds, env_info)

    token_store = load_token_store_from_files(
        core_token_file=os.environ.get("CORE_TOKEN_FILE"),
        observer_token_file=os.environ.get("OBSERVER_TOKEN_FILE"),
    )

    app = spec.build_app(client=client, token_store=token_store, creds=creds, env_info=env_info)

    uvicorn.run(
        app,
        log_config=None,
        host=os.environ.get("HOST", "0.0.0.0"),
        port=int(os.environ.get("PORT", str(spec.default_port))),
    )