"""Worker configuration, parsed once from the environment.

All env knobs the workers honor live here so there's a single source of truth (the
two market workers used to each re-parse the same ~15 vars). Frozen dataclass — read
it, don't mutate it.
"""

import os
from dataclasses import dataclass


def _int(name: str, default: int) -> int:
    return int(os.environ.get(name, str(default)))


def _float(name: str, default: float) -> float:
    return float(os.environ.get(name, str(default)))


def _flag(name: str) -> bool:
    return os.environ.get(name) == "1"


@dataclass(frozen=True)
class Settings:
    # C2
    c2_url: str
    token: str
    # Session / pacing
    market_url: str          # "" => use the worker's own default page
    solve_seconds: int
    delay: float
    jitter: float
    idle_seconds: int
    # Browser
    browser_path: str | None
    load_images: bool
    chrome_no_sandbox: bool
    # Browser bring-up resilience. nodriver gives Chromium only ~2.75s to open its
    # DevTools port before raising "Failed to connect to browser"; when many replicas
    # cold-start at once on a CPU-bound host they blow that window. A randomized pre-launch
    # delay de-synchronizes the herd, and a few retries cover the residual slow starts.
    startup_jitter: float
    browser_start_retries: int
    browser_start_backoff: float
    # Proxy (auth-free fallback)
    proxy: str | None
    # IPRoyal residential gateway
    iproyal_host: str
    iproyal_port: int
    iproyal_username: str | None
    iproyal_password: str | None
    iproyal_country: str
    iproyal_lifetime_min: int
    # Logging
    log_level: str
    log_json: bool

    @property
    def use_iproyal(self) -> bool:
        """IPRoyal takes priority over a plain PROXY when its creds are set."""
        return bool(self.iproyal_username and self.iproyal_password)

    @classmethod
    def from_env(cls) -> "Settings":
        return cls(
            c2_url=os.environ.get("C2_URL", "http://localhost:5080").rstrip("/"),
            token=os.environ.get("WORKER_TOKEN", "dev-worker-token"),
            market_url=os.environ.get("MARKET_URL", ""),
            solve_seconds=_int("SOLVE_SECONDS", 30),
            delay=_float("DELAY", 2.0),
            jitter=_float("JITTER", 1.5),
            idle_seconds=_int("IDLE_SECONDS", 10),
            browser_path=os.environ.get("BROWSER_PATH") or None,
            # Residential proxy is metered per GB; Cloudflare gates on JS, not images, and
            # the market APIs are pure JSON — so block images unless explicitly debugging.
            load_images=_flag("LOAD_IMAGES"),
            chrome_no_sandbox=_flag("CHROME_NO_SANDBOX"),
            startup_jitter=_float("STARTUP_JITTER", 8.0),
            browser_start_retries=_int("BROWSER_START_RETRIES", 4),
            browser_start_backoff=_float("BROWSER_START_BACKOFF", 2.0),
            proxy=os.environ.get("PROXY") or None,
            iproyal_host=os.environ.get("IPROYAL_HOST", "geo.iproyal.com"),
            iproyal_port=_int("IPROYAL_PORT", 12321),
            iproyal_username=os.environ.get("IPROYAL_USERNAME") or None,
            iproyal_password=os.environ.get("IPROYAL_PASSWORD") or None,
            iproyal_country=os.environ.get("IPROYAL_COUNTRY", "us").strip().lower(),
            iproyal_lifetime_min=_int("IPROYAL_LIFETIME_MIN", 60),
            log_level=os.environ.get("LOG_LEVEL", "INFO").upper(),
            log_json=_flag("LOG_JSON"),
        )