update AccountController with balance

src/main/kotlin/ltd/lulz/controller/AccountController.kt

@@ -1,18 +1,26 @@
 package ltd.lulz.controller
 
+import io.github.oshai.kotlinlogging.KotlinLogging
 import jakarta.validation.Valid
+import java.util.UUID
 import ltd.lulz.model.Account
 import ltd.lulz.service.AccountService
 import ltd.lulz.util.toEntity
 import ltd.lulz.util.toResponse
 import org.springframework.http.HttpStatus.CREATED
+import org.springframework.http.HttpStatus.NOT_FOUND
 import org.springframework.validation.annotation.Validated
+import org.springframework.web.bind.annotation.GetMapping
+import org.springframework.web.bind.annotation.PathVariable
 import org.springframework.web.bind.annotation.PostMapping
 import org.springframework.web.bind.annotation.RequestBody
 import org.springframework.web.bind.annotation.ResponseStatus
 import org.springframework.web.bind.annotation.RestController
+import org.springframework.web.server.ResponseStatusException
 import reactor.core.publisher.Mono
 
+private val log = KotlinLogging.logger {}
+
 @RestController
 @Validated
 class AccountController(
@@ -25,4 +33,12 @@ class AccountController(
         @Valid @RequestBody request: Account.Request,
     ): Mono<Account.Response> = accountService.create(request.toEntity())
         .map { it.toResponse() }
+
+    @GetMapping("/balance/account-{account}")
+    fun balance(
+        @PathVariable account: UUID,
+    ): Mono<Account.Response> = accountService.getById(account)
+        .map { it.toResponse() }
+        .switchIfEmpty(Mono.error(ResponseStatusException(NOT_FOUND)))
+        .doOnError { log.debug { "account $account not found for balance" } }
 }