import { betterAuth } from "better-auth";
import { prismaAdapter } from "better-auth/adapters/prisma";
import { admin, organization } from "better-auth/plugins";
import { nextCookies } from "better-auth/next-js";
import { prisma } from "@/lib/db";
import { sendEmail, emailLayout } from "@/lib/email";

const appUrl = process.env.NEXT_PUBLIC_APP_URL || "http://localhost:3000";

const googleConfigured = !!(process.env.GOOGLE_CLIENT_ID && process.env.GOOGLE_CLIENT_SECRET);

// Fail fast in production if the signing secret is missing — sessions/cookies are
// only secure when BETTER_AUTH_SECRET is set. Stay frictionless in dev/test.
if (!process.env.BETTER_AUTH_SECRET && process.env.NODE_ENV === "production") {
  throw new Error("BETTER_AUTH_SECRET must be set in production.");
}

export const auth = betterAuth({
  appName: "PodcastYes",
  secret: process.env.BETTER_AUTH_SECRET,
  baseURL: process.env.BETTER_AUTH_URL ?? appUrl,
  database: prismaAdapter(prisma, { provider: "postgresql" }),

  // Built-in brute-force protection for auth endpoints (login, password reset, etc).
  // 30 requests per 60s window per IP.
  rateLimit: { enabled: true, window: 60, max: 30 },

  emailAndPassword: {
    enabled: true,
    // SECURITY GATE (currently OPEN): unverified emails can sign in. Flip this to
    // `true` once email delivery is confirmed working in prod. Left `false` for now
    // so existing dev accounts aren't locked out. Verification emails ARE sent on
    // signup (see emailVerification.sendOnSignUp below), so users can verify already.
    requireEmailVerification: false,
    minPasswordLength: 8,
    async sendResetPassword({ user, url }) {
      await sendEmail({
        to: user.email,
        subject: "Reset your PodcastYes password",
        html: emailLayout(
          "Reset your password",
          "Click the button below to choose a new password.",
          { label: "Reset password", url }
        ),
        text: `Reset your password: ${url}`,
      });
    },
  },

  emailVerification: {
    sendOnSignUp: true,
    async sendVerificationEmail({ user, url }) {
      await sendEmail({
        to: user.email,
        subject: "Verify your email for PodcastYes",
        html: emailLayout(
          "Confirm your email",
          "Confirm your email address to secure your account.",
          { label: "Verify email", url }
        ),
        text: `Verify your email: ${url}`,
      });
    },
  },

  socialProviders: googleConfigured
    ? {
        google: {
          clientId: process.env.GOOGLE_CLIENT_ID!,
          clientSecret: process.env.GOOGLE_CLIENT_SECRET!,
        },
      }
    : undefined,

  session: {
    expiresIn: 60 * 60 * 24 * 30, // 30 days
    updateAge: 60 * 60 * 24, // refresh daily
    // Cache the session in a signed cookie to avoid a DB hit on every request.
    // Tradeoff: a banned/demoted user keeps cached access until the cache expires,
    // so we keep the window short (60s). Shorter = faster revocation but more DB hits.
    cookieCache: { enabled: true, maxAge: 60 },
  },

  account: {
    accountLinking: { enabled: true, trustedProviders: ["google"] },
  },

  plugins: [
    admin({ defaultRole: "user", adminRoles: ["admin"] }),
    organization({
      teams: { enabled: true, maximumTeams: 1 },
      // Agency seat cap is enforced in app logic against the subscription's seat count.
      membershipLimit: 5,
    }),
    // Must remain last: lets Server Actions / route handlers set auth cookies.
    nextCookies(),
  ],
});

export type Session = typeof auth.$Infer.Session;