export type AimTrainerCrosshairStyle = "classic" | "dot" | "cross" | "circle" | "chevron";

export type AimTrainerCrosshairPrefs = {
  style: AimTrainerCrosshairStyle;
  color: string;
  scale: number;
};

export const AIM_TRAINER_CROSSHAIR_STORAGE_KEY = "ptf.aimTrainer.crosshair";
export const AIM_TRAINER_CROSSHAIR_SCALE_MIN = 1;
export const AIM_TRAINER_CROSSHAIR_SCALE_MAX = 2.5;
export const AIM_TRAINER_CROSSHAIR_SCALE_STEP = 0.1;

export const AIM_TRAINER_CROSSHAIR_STYLES = [
  "classic",
  "dot",
  "cross",
  "circle",
  "chevron",
] as const satisfies readonly AimTrainerCrosshairStyle[];

export const DEFAULT_AIM_TRAINER_CROSSHAIR_PREFS: AimTrainerCrosshairPrefs = {
  style: "classic",
  color: "#d8d3b6",
  scale: AIM_TRAINER_CROSSHAIR_SCALE_MIN,
};

function createDefaultAimTrainerCrosshairPrefs(): AimTrainerCrosshairPrefs {
  return { ...DEFAULT_AIM_TRAINER_CROSSHAIR_PREFS };
}

function isRecord(value: unknown): value is Record<string, unknown> {
  return typeof value === "object" && value !== null;
}

function isAimTrainerCrosshairStyle(value: unknown): value is AimTrainerCrosshairStyle {
  return (
    typeof value === "string" &&
    AIM_TRAINER_CROSSHAIR_STYLES.some((style) => style === value)
  );
}

function isHexColor(value: unknown): value is string {
  return typeof value === "string" && /^#[0-9a-f]{3}(?:[0-9a-f]{3})?$/i.test(value);
}

export function normalizeAimTrainerCrosshairScale(value: unknown): number {
  if (typeof value !== "number" || !Number.isFinite(value)) {
    return AIM_TRAINER_CROSSHAIR_SCALE_MIN;
  }

  const clamped = Math.min(
    AIM_TRAINER_CROSSHAIR_SCALE_MAX,
    Math.max(AIM_TRAINER_CROSSHAIR_SCALE_MIN, value),
  );
  return Number(
    (Math.round(clamped / AIM_TRAINER_CROSSHAIR_SCALE_STEP) * AIM_TRAINER_CROSSHAIR_SCALE_STEP).toFixed(
      1,
    ),
  );
}

export function loadAimTrainerCrosshairPrefs(): AimTrainerCrosshairPrefs {
  const defaults = createDefaultAimTrainerCrosshairPrefs();
  if (typeof window === "undefined") return defaults;

  try {
    const stored = window.localStorage.getItem(AIM_TRAINER_CROSSHAIR_STORAGE_KEY);
    if (!stored) return defaults;

    const parsed: unknown = JSON.parse(stored);
    if (!isRecord(parsed) || !isAimTrainerCrosshairStyle(parsed.style)) return defaults;
    if (!isHexColor(parsed.color)) return defaults;

    return {
      style: parsed.style,
      color: parsed.color,
      scale: normalizeAimTrainerCrosshairScale(parsed.scale),
    };
  } catch {
    return defaults;
  }
}

export function saveAimTrainerCrosshairPrefs(prefs: AimTrainerCrosshairPrefs): void {
  if (typeof window === "undefined") return;

  try {
    window.localStorage.setItem(AIM_TRAINER_CROSSHAIR_STORAGE_KEY, JSON.stringify(prefs));
  } catch {
    return;
  }
}