export const CONTACT_PROTECTION_SETTINGS_KEY = "contact_protection_settings";
export const CONTACT_RATE_LIMIT_KEY_PREFIX = "contact_rate_limit";

export type ContactProtectionSettings = {
  turnstile: {
    enabled: boolean;
    siteKey: string;
    secretKey: string;
  };
  rateLimit: {
    enabled: boolean;
    maxRequests: number;
    windowMinutes: number;
  };
};

export type ContactProtectionFormValues = {
  turnstile: {
    enabled: boolean;
    siteKey: string;
    secretKey: string;
    hasSecretKey: boolean;
  };
  rateLimit: {
    enabled: boolean;
    maxRequests: number;
    windowMinutes: number;
  };
};

export type PublicContactProtectionSettings = {
  turnstile: {
    enabled: boolean;
    siteKey: string;
  };
  rateLimit: {
    enabled: boolean;
  };
};

export function buildDefaultContactProtectionSettings(): ContactProtectionSettings {
  return {
    turnstile: {
      enabled: false,
      siteKey: "",
      secretKey: "",
    },
    rateLimit: {
      enabled: true,
      maxRequests: 5,
      windowMinutes: 10,
    },
  };
}

function parsePositiveInt(value: unknown, fallback: number) {
  const parsed =
    typeof value === "number"
      ? value
      : typeof value === "string"
        ? Number.parseInt(value, 10)
        : fallback;

  return Number.isInteger(parsed) && parsed > 0 ? parsed : fallback;
}

export function parseContactProtectionValue(
  rawValue: string | null | undefined,
): ContactProtectionSettings {
  const defaults = buildDefaultContactProtectionSettings();

  if (!rawValue) {
    return defaults;
  }

  try {
    const parsed = JSON.parse(rawValue) as Record<string, unknown>;
    const turnstile = parsed.turnstile && typeof parsed.turnstile === "object"
      ? (parsed.turnstile as Record<string, unknown>)
      : {};
    const rateLimit = parsed.rateLimit && typeof parsed.rateLimit === "object"
      ? (parsed.rateLimit as Record<string, unknown>)
      : {};

    return {
      turnstile: {
        enabled: Boolean(turnstile.enabled),
        siteKey: typeof turnstile.siteKey === "string" ? turnstile.siteKey.trim() : "",
        secretKey: typeof turnstile.secretKey === "string" ? turnstile.secretKey : "",
      },
      rateLimit: {
        enabled: rateLimit.enabled === undefined ? defaults.rateLimit.enabled : Boolean(rateLimit.enabled),
        maxRequests: parsePositiveInt(rateLimit.maxRequests, defaults.rateLimit.maxRequests),
        windowMinutes: parsePositiveInt(rateLimit.windowMinutes, defaults.rateLimit.windowMinutes),
      },
    };
  } catch {
    return defaults;
  }
}

export function toContactProtectionFormValues(
  settings: ContactProtectionSettings,
): ContactProtectionFormValues {
  return {
    turnstile: {
      enabled: settings.turnstile.enabled,
      siteKey: settings.turnstile.siteKey,
      secretKey: "",
      hasSecretKey: Boolean(settings.turnstile.secretKey),
    },
    rateLimit: {
      enabled: settings.rateLimit.enabled,
      maxRequests: settings.rateLimit.maxRequests,
      windowMinutes: settings.rateLimit.windowMinutes,
    },
  };
}

export function toPublicContactProtectionSettings(
  settings: ContactProtectionSettings,
): PublicContactProtectionSettings {
  return {
    turnstile: {
      enabled: settings.turnstile.enabled && Boolean(settings.turnstile.siteKey),
      siteKey: settings.turnstile.siteKey,
    },
    rateLimit: {
      enabled: settings.rateLimit.enabled,
    },
  };
}