/**
 * Magic-link send + consume via first-party FDI proxy.
 * Briven emails open: {origin}/auth/verify?preAuthSessionId&linkCode&deviceId
 */

import {
  getBrivenAuthPublicKey,
  getBrivenProjectId,
} from "@/lib/auth-config";
import {
  establishPortalSession,
  userIdFromEngineBody,
} from "@/lib/portal-session";

function fdiHeaders(): Record<string, string> {
  const projectId = getBrivenProjectId() ?? "";
  const publicKey = getBrivenAuthPublicKey() ?? "";
  const headers: Record<string, string> = {
    "content-type": "application/json",
    accept: "application/json",
    rid: "passwordless",
    "fdi-version": "1.19",
    "st-auth-mode": "cookie",
  };
  if (projectId.startsWith("p_")) {
    headers["x-briven-project-id"] = projectId;
  }
  if (publicKey.startsWith("pk_briven_auth_")) {
    headers.authorization = `Bearer ${publicKey}`;
  }
  return headers;
}

export async function sendMagicLinkEmail(input: {
  email: string;
  /** Where to go after verify succeeds */
  redirectTo?: string;
}): Promise<{ ok: true } | { ok: false; message: string }> {
  const email = input.email.trim().toLowerCase();
  if (!email.includes("@")) {
    return { ok: false, message: "Enter a valid email." };
  }

  if (typeof window !== "undefined" && input.redirectTo) {
    sessionStorage.setItem("krypco_magic_redirect", input.redirectTo);
  }

  const magicLinkBaseUrl =
    typeof window !== "undefined"
      ? `${window.location.origin}/auth/verify`
      : "https://krypco.eu/auth/verify";

  try {
    const res = await fetch("/api/auth/signinup/code", {
      method: "POST",
      credentials: "include",
      headers: fdiHeaders(),
      body: JSON.stringify({
        email,
        flowType: "MAGIC_LINK",
        magicLinkBaseUrl,
      }),
    });
    const data = (await res.json().catch(() => ({}))) as Record<
      string,
      unknown
    >;
    if (!res.ok || data.status !== "OK") {
      return {
        ok: false,
        message:
          typeof data.message === "string"
            ? data.message
            : "Could not send magic link.",
      };
    }
    return { ok: true };
  } catch (e) {
    return {
      ok: false,
      message: e instanceof Error ? e.message : "network error",
    };
  }
}

export async function consumeMagicLink(input: {
  preAuthSessionId: string;
  deviceId: string;
  linkCode: string;
}): Promise<
  | { ok: true; userId: string }
  | { ok: false; message: string }
> {
  try {
    const res = await fetch("/api/auth/signinup/code/consume", {
      method: "POST",
      credentials: "include",
      headers: fdiHeaders(),
      body: JSON.stringify({
        preAuthSessionId: input.preAuthSessionId,
        deviceId: input.deviceId,
        linkCode: input.linkCode,
      }),
    });
    const data = (await res.json().catch(() => ({}))) as Record<
      string,
      unknown
    >;
    if (res.ok && data.status === "OK") {
      const userId = userIdFromEngineBody(data) || "session";
      await establishPortalSession({ userId });
      return { ok: true, userId };
    }
    return {
      ok: false,
      message:
        typeof data.message === "string"
          ? data.message
          : "This sign-in link is invalid or expired. Request a new one.",
    };
  } catch (e) {
    return {
      ok: false,
      message: e instanceof Error ? e.message : "network error",
    };
  }
}