import { NextResponse } from "next/server"
import { AuthError } from "next-auth"

import { dtmcApiCallback } from "@/constants/routes/dtmc"
import { env } from "@/env/server"
import { internalServerError, serviceUnavailable } from "@/server/errors/next"

import { signIn } from "@/auth.dtmc"

export async function GET() {
  try {
    const redirectUrl = await signIn(
      "microsoft-entra-id",
      {
        redirectTo: `${env.PUBLIC_URL}${dtmcApiCallback}`,
        redirect: false,
      },
      {
        prompt: "login",
      }
    )

    if (redirectUrl) {
      console.log(`[dtmc] redirecting to: ${redirectUrl}`)
      return NextResponse.redirect(redirectUrl)
    } else {
      console.error(`[dtmc] missing redirectUrl response from signIn()`)
      return internalServerError(
        "[dtmc] Missing redirect URL from authentication service"
      )
    }
  } catch (error) {
    if (error instanceof AuthError) {
      console.error({ signInAuthError: error })
      return serviceUnavailable(
        "[dtmc] Microsoft authentication service unavailable"
      )
    } else {
      console.error({ signInError: error })
      return internalServerError(
        "[dtmc] Unexpected error during authentication"
      )
    }
  }
}