feat(locale): persist household and member preferences

packages/application/src/locale-preference-service.ts

@@ -0,0 +1,94 @@
+import type { SupportedLocale } from '@household/domain'
+import type { HouseholdConfigurationRepository } from '@household/ports'
+
+export interface LocalePreferenceService {
+  updateMemberLocale(input: {
+    householdId: string
+    telegramUserId: string
+    locale: SupportedLocale
+  }): Promise<
+    | {
+        status: 'updated'
+        member: {
+          householdId: string
+          telegramUserId: string
+          preferredLocale: SupportedLocale | null
+          householdDefaultLocale: SupportedLocale
+        }
+      }
+    | {
+        status: 'rejected'
+        reason: 'member_not_found'
+      }
+  >
+  updateHouseholdLocale(input: {
+    householdId: string
+    actorIsAdmin: boolean
+    locale: SupportedLocale
+  }): Promise<
+    | {
+        status: 'updated'
+        household: {
+          householdId: string
+          defaultLocale: SupportedLocale
+        }
+      }
+    | {
+        status: 'rejected'
+        reason: 'not_admin'
+      }
+  >
+}
+
+export function createLocalePreferenceService(
+  repository: HouseholdConfigurationRepository
+): LocalePreferenceService {
+  return {
+    async updateMemberLocale(input) {
+      const member = await repository.updateMemberPreferredLocale(
+        input.householdId,
+        input.telegramUserId,
+        input.locale
+      )
+
+      if (!member) {
+        return {
+          status: 'rejected',
+          reason: 'member_not_found' as const
+        }
+      }
+
+      return {
+        status: 'updated',
+        member: {
+          householdId: member.householdId,
+          telegramUserId: member.telegramUserId,
+          preferredLocale: member.preferredLocale,
+          householdDefaultLocale: member.householdDefaultLocale
+        }
+      }
+    },
+
+    async updateHouseholdLocale(input) {
+      if (!input.actorIsAdmin) {
+        return {
+          status: 'rejected',
+          reason: 'not_admin' as const
+        }
+      }
+
+      const household = await repository.updateHouseholdDefaultLocale(
+        input.householdId,
+        input.locale
+      )
+
+      return {
+        status: 'updated',
+        household: {
+          householdId: household.householdId,
+          defaultLocale: household.defaultLocale
+        }
+      }
+    }
+  }
+}