model FeatureFlag {
  id            String              @id @default(cuid())
  createdAt     DateTime            @default(now())
  updatedAt     DateTime            @updatedAt
  key           String?
  scope         String              @default("global")
  tenantId      String?
  userId        String?
  name          String
  description   String
  enabled       Boolean             @default(false)
  // v2 targeting engine fields (task #53). All nullable / defaulted so
  // legacy rows continue to evaluate via boolean `enabled` only.
  rules         Json?
  variants      Json[]              @default([])
  enabledFrom   DateTime?
  enabledUntil  DateTime?
  parentFlagId  String?
  parentFlag    FeatureFlag?        @relation("FeatureFlagDependency", fields: [parentFlagId], references: [id], onDelete: SetNull)
  childFlags    FeatureFlag[]       @relation("FeatureFlagDependency")
  audits        FeatureFlagAudit[]
  events        AnalyticsEvent[]
  filters       FeatureFlagFilter[]

  @@unique([name, description])
  @@index([key, scope], name: "feature_flag_key_scope_idx")
  @@index([tenantId, key], name: "feature_flag_tenant_key_idx")
  @@index([userId, key], name: "feature_flag_user_key_idx")
  @@index([parentFlagId], name: "feature_flag_parent_idx")
}

model FeatureFlagFilter {
  id            String      @id @default(cuid())
  createdAt     DateTime    @default(now())
  featureFlagId String
  featureFlag   FeatureFlag @relation(fields: [featureFlagId], references: [id], onDelete: Cascade)
  type          String // [FeatureFlagsFilterType] percentage, darkMode, language.is, page.is, analytics.browser.is...
  value         String? // 0-100, true, false, en, de, fr, ...
  action        String?
}

/// Append-only audit trail for every mutation of a FeatureFlag (create / update / delete / toggle).
/// Never UPDATE or DELETE rows from app code — preserves tamper-resistance for compliance.
model FeatureFlagAudit {
  id           String      @id @default(cuid())
  flagId       String
  flag         FeatureFlag @relation(fields: [flagId], references: [id], onDelete: Cascade)
  actorUserId  String?
  action       String // create | update | delete | toggle
  oldValue     Json?
  newValue     Json?
  createdAt    DateTime    @default(now())

  @@index([flagId, createdAt], name: "feature_flag_audit_flag_idx")
  @@index([actorUserId, createdAt], name: "feature_flag_audit_actor_idx")
}