Initial commit for first version of project

GasTankAR/Views/Docuframe/DocuframeViewModel.swift

@@ -0,0 +1,118 @@
+//
+//  DocuframeViewModel.swift
+//  GasTankAR
+//
+//  Created by Dennis Nemec on 28.08.26.
+//
+
+import Foundation
+import SwiftData
+
+/// Präsentationslogik für den DOCUframe-Tab: verwaltet die Fotoauswahl und stößt Upload bzw.
+/// Mailversand über den injizierten ``DocuframeService`` an. Kennt keine UI-Details.
+@MainActor
+@Observable
+final class DocuframeViewModel {
+    /// Auswahl anhand der stabilen SwiftData-Identität der Fotos.
+    var selectedIDs: Set<PersistentIdentifier> = []
+    /// Läuft gerade ein Upload/Mailversand?
+    private(set) var isProcessing = false
+    /// Ergebnis des letzten Vorgangs für die Anzeige (nil = kein Hinweis).
+    var result: DocuframeActionResult?
+
+    @ObservationIgnored private let service: DocuframeService
+
+    /// Der Service wird injiziert (Default: Stub) – austauschbar für echte Anbindung oder Tests.
+    init(service: DocuframeService = StubDocuframeService()) {
+        self.service = service
+    }
+
+    var hasSelection: Bool { !selectedIDs.isEmpty }
+    var selectionCount: Int { selectedIDs.count }
+
+    func isSelected(_ photo: ProjectPhoto) -> Bool {
+        selectedIDs.contains(photo.persistentModelID)
+    }
+
+    func toggleSelection(_ photo: ProjectPhoto) {
+        let id = photo.persistentModelID
+        if selectedIDs.contains(id) {
+            selectedIDs.remove(id)
+        } else {
+            selectedIDs.insert(id)
+        }
+    }
+
+    func upload(from photos: [ProjectPhoto], leadID: String) async {
+        await perform(from: photos, leadID: leadID, successText: "in DOCUframe hochgeladen") {
+            try await service.uploadPhotos($0, projectLeadID: $1)
+        }
+    }
+
+    func sendEmail(from photos: [ProjectPhoto], leadID: String) async {
+        await perform(from: photos, leadID: leadID, successText: "per E-Mail versendet") {
+            try await service.sendEmail($0, projectLeadID: $1)
+        }
+    }
+
+    // MARK: - Gemeinsame Ausführung
+
+    private func perform(
+        from photos: [ProjectPhoto],
+        leadID: String,
+        successText: String,
+        action: ([DocuframePhoto], String) async throws -> Void
+    ) async {
+        let selected = photos.filter { selectedIDs.contains($0.persistentModelID) }
+        guard !selected.isEmpty else {
+            result = .failure(message: DocuframeError.noPhotosSelected.localizedDescription)
+            return
+        }
+
+        isProcessing = true
+        defer { isProcessing = false }
+
+        let payload = selected.map(Self.makeDTO)
+        do {
+            try await action(payload, leadID)
+            result = .success(message: "\(selected.count) Foto(s) \(successText).")
+        } catch {
+            // Bei HTTP 4xx/5xx (und anderen Fehlern) den Nutzer informieren.
+            result = .failure(message: error.localizedDescription)
+        }
+    }
+
+    /// Bildet das Persistenz-Model auf ein persistenzunabhängiges Domänen-DTO ab.
+    private static func makeDTO(_ photo: ProjectPhoto) -> DocuframePhoto {
+        DocuframePhoto(
+            imageData: photo.imageData,
+            creationDate: photo.creationDate,
+            latitude: photo.latitude,
+            longitude: photo.longitude
+        )
+    }
+}
+
+/// Ergebnis eines DOCUframe-Vorgangs für die Anzeige (Erfolg oder Fehler).
+enum DocuframeActionResult {
+    case success(message: String)
+    case failure(message: String)
+
+    var title: String {
+        switch self {
+        case .success: "Erledigt"
+        case .failure: "Fehler"
+        }
+    }
+
+    var message: String {
+        switch self {
+        case .success(let message), .failure(let message): message
+        }
+    }
+
+    var isError: Bool {
+        if case .failure = self { return true }
+        return false
+    }
+}