field_ios

In-the-field app for Radroots on iOS
git clone https://radroots.dev/git/field_ios.git
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TeraRuntimeInvalidation.swift (3423B)

      1 import Foundation
      2 
      3 enum TeraRuntimeChangeKind: Sendable, Equatable, Hashable {
      4   case initial
      5   case identity
      6   case settings
      7   case profile
      8   case today
      9   case drafts
     10   case relay
     11   case media
     12   case lifecycle
     13 }
     14 
     15 enum TeraRuntimeChangeDelivery: Sendable, Equatable {
     16   case change
     17   case resnapshotRequired
     18 }
     19 
     20 struct TeraRuntimeChangeScope: Sendable, Equatable, Hashable {
     21   let publicKey: String
     22   let sourceGeneration: String
     23   let context: TeraLocalNetwork?
     24 }
     25 
     26 /// A hint to query state, never a durable mutation receipt or host session ID.
     27 /// Revisions are comparable within one epoch, domain and exact scope only.
     28 struct TeraRuntimeChange: Sendable, Equatable {
     29   let schemaVersion: UInt16
     30   let scope: TeraRuntimeChangeScope
     31   let epoch: String
     32   let revision: TeraProjectionRevision
     33   let delivery: TeraRuntimeChangeDelivery
     34   let kind: TeraRuntimeChangeKind
     35   let entityID: String?
     36 
     37   func matches(_ configuration: TeraRuntimeLaunchConfiguration?) -> Bool {
     38     guard let configuration else { return false }
     39     return schemaVersion == 3
     40       && Self.isHex(epoch, count: 32)
     41       && Self.isHex(scope.publicKey, count: 64)
     42       && Self.isHex(scope.sourceGeneration, count: 64)
     43       && scope.publicKey == configuration.publicKeyHex
     44       && scope.sourceGeneration == configuration.sourceGenerationHex
     45       && (scope.context == nil || scope.context?.schemaVersion == 1)
     46   }
     47 
     48   func matches(context: TeraLocalNetwork?) -> Bool {
     49     scope.context == nil || scope.context == context
     50   }
     51 
     52   func requiringResnapshot() -> Self {
     53     Self(
     54       schemaVersion: schemaVersion,
     55       scope: TeraRuntimeChangeScope(publicKey: scope.publicKey, sourceGeneration: scope.sourceGeneration, context: nil),
     56       epoch: epoch, revision: TeraProjectionRevision(rawValue: 0),
     57       delivery: .resnapshotRequired, kind: .initial, entityID: nil
     58     )
     59   }
     60 
     61   /// Loss leaves an account-wide gap queued or already delivered, even if this
     62   /// is the producer's final event. The existing buffer capacity stays fixed.
     63   func yield(to continuation: AsyncStream<Self>.Continuation) {
     64     if case .dropped = continuation.yield(self) {
     65       continuation.yield(requiringResnapshot())
     66     }
     67   }
     68 
     69   private static func isHex(_ value: String, count: Int) -> Bool {
     70     value.utf8.count == count && value.utf8.contains(where: { $0 != 48 })
     71       && value.utf8.allSatisfy { (48 ... 57).contains($0) || (97 ... 102).contains($0) }
     72   }
     73 }
     74 
     75 /// One subscription retains at most one watermark for each of the nine domains.
     76 /// Domain counters cover all contexts; context filtering happens at each store.
     77 struct TeraInvalidationAdmission {
     78   private var epoch: String?
     79   private var revisions: [TeraRuntimeChangeKind: TeraProjectionRevision] = [:]
     80 
     81   mutating func accept(_ change: TeraRuntimeChange) -> Bool {
     82     guard epoch == nil || epoch == change.epoch else { return false }
     83     epoch = change.epoch
     84     if change.delivery == .resnapshotRequired {
     85       return true
     86     }
     87     if let previous = revisions[change.kind], let next = change.revision.rawValue {
     88       guard let value = previous.rawValue, next > value else { return false }
     89     }
     90     revisions[change.kind] = change.revision
     91     return true
     92   }
     93 }
     94 
     95 struct TeraRuntimeSubscription {
     96   let generation: TeraSessionGeneration
     97   let continuation: AsyncStream<TeraRuntimeChange>.Continuation
     98   var token: (any TeraRuntimeSubscriptionToken)?
     99   var admission = TeraInvalidationAdmission()
    100 }