"""Runtime settings (env / .env) - single source of truth for configuration.

Symbols are NOT configured here; see `us2kr.symbols`.
"""

from __future__ import annotations

from datetime import date
from pathlib import Path
from typing import Annotated

from pydantic import Field, field_validator
from pydantic_settings import BaseSettings, NoDecode, SettingsConfigDict

KST = "Asia/Seoul"
ET = "America/New_York"


class Settings(BaseSettings):
    model_config = SettingsConfigDict(
        env_file=".env", env_file_encoding="utf-8", extra="ignore", populate_by_name=True
    )

    # --- MiniMax (OpenAI-compatible endpoint) ---
    minimax_api_key: str = Field(default="", alias="MINIMAX_API_KEY")
    minimax_base_url: str = Field(default="https://api.minimax.io/v1", alias="MINIMAX_BASE_URL")
    minimax_model: str = Field(default="MiniMax-M3", alias="MINIMAX_MODEL")
    minimax_fallback_models: Annotated[list[str], NoDecode] = Field(
        default_factory=lambda: ["MiniMax-M2.7", "MiniMax-M2.5"], alias="MINIMAX_FALLBACK_MODELS"
    )
    minimax_max_completion_tokens: int = Field(default=16384, alias="MINIMAX_MAX_COMPLETION_TOKENS")
    minimax_timeout_seconds: float = Field(default=180.0, alias="MINIMAX_TIMEOUT_SECONDS")

    # --- Delivery ---
    telegram_bot_token: str | None = Field(default=None, alias="TELEGRAM_BOT_TOKEN")
    telegram_chat_id: str | None = Field(default=None, alias="TELEGRAM_CHAT_ID")

    # --- Blogger (optional; issue the refresh token once with `us2kr blogger-auth`) ---
    blogger_client_id: str | None = Field(default=None, alias="BLOGGER_CLIENT_ID")
    blogger_client_secret: str | None = Field(default=None, alias="BLOGGER_CLIENT_SECRET")
    blogger_refresh_token: str | None = Field(default=None, alias="BLOGGER_REFRESH_TOKEN")
    blogger_blog_id: str | None = Field(default=None, alias="BLOGGER_BLOG_ID")
    blogger_labels: Annotated[list[str], NoDecode] = Field(
        default_factory=lambda: ["미국증시", "마감브리핑"], alias="BLOGGER_LABELS"
    )

    # --- Optional data keys ---
    fred_api_key: str | None = Field(default=None, alias="FRED_API_KEY")

    # --- SearXNG (optional news search; instance must enable the json output format) ---
    searxng_base_url: str | None = Field(default=None, alias="SEARXNG_BASE_URL")
    # Empty -> collector defaults (us2kr.collectors.searx.DEFAULT_QUERIES).
    searxng_queries: Annotated[list[str], NoDecode] = Field(
        default_factory=list, alias="US2KR_SEARXNG_QUERIES"
    )

    # --- Paths ---
    data_dir: Path = Field(default=Path("data"), alias="US2KR_DATA_DIR")
    reports_dir: Path = Field(default=Path("reports"), alias="US2KR_REPORTS_DIR")
    log_dir: Path = Field(default=Path("logs"), alias="US2KR_LOG_DIR")

    # --- Scheduling policy ---
    run_offset_minutes: int = Field(default=75, alias="US2KR_RUN_OFFSET_MINUTES")
    catchup_window_hours: int = Field(default=3, alias="US2KR_CATCHUP_WINDOW_HOURS")
    # Skip only briefings that become pointless: a KRX holiday where the *next* US session closes before
    # KRX trades again (e.g. mid-week Chuseok). Friday sessions are always delivered (used for Monday open).
    skip_when_krx_closed: bool = Field(default=False, alias="US2KR_SKIP_WHEN_KRX_CLOSED")
    # Ad-hoc KRX closures missing from exchange_calendars (e.g. election days), CSV of YYYY-MM-DD.
    krx_extra_holidays: Annotated[list[date], NoDecode] = Field(default_factory=list, alias="US2KR_KRX_EXTRA_HOLIDAYS")
    premarket_update_enabled: bool = Field(default=False, alias="US2KR_PREMARKET_UPDATE_ENABLED")
    premarket_time_kst: str = Field(default="08:20", alias="US2KR_PREMARKET_TIME_KST")

    # --- Collection policy ---
    news_lookback_hours: int = Field(default=18, alias="US2KR_NEWS_LOOKBACK_HOURS")
    news_max_items: int = Field(default=40, alias="US2KR_NEWS_MAX_ITEMS")

    # --- LLM verification (fact-check pass over the generated report) ---
    verify_enabled: bool = Field(default=True, alias="US2KR_VERIFY_ENABLED")

    log_level: str = Field(default="INFO", alias="US2KR_LOG_LEVEL")

    @field_validator(
        "minimax_fallback_models", "krx_extra_holidays", "searxng_queries", "blogger_labels", mode="before"
    )
    @classmethod
    def _split_csv(cls, v):
        if isinstance(v, str):
            return [s.strip() for s in v.split(",") if s.strip()]
        return v

    @property
    def db_path(self) -> Path:
        return self.data_dir / "us2kr.sqlite3"

    @property
    def telegram_enabled(self) -> bool:
        return bool(self.telegram_bot_token and self.telegram_chat_id)

    @property
    def blogger_enabled(self) -> bool:
        return bool(
            self.blogger_client_id
            and self.blogger_client_secret
            and self.blogger_refresh_token
            and self.blogger_blog_id
        )


def get_settings() -> Settings:
    """Load settings from environment / .env (called once per process by the CLI)."""
    return Settings()