Impressia/CoreData/ViewedStatusHandler.swift

112 lines
4.0 KiB
Swift

//
// https://mczachurski.dev
// Copyright © 2023 Marcin Czachurski and the repository contributors.
// Licensed under the Apache License 2.0.
//
import Foundation
import SwiftData
import PixelfedKit
class ViewedStatusHandler {
public static let shared = ViewedStatusHandler()
private init() { }
/// Append new visible statuses to database.
func append(contentsOf statuses: [Status], accountId: String, modelContext: ModelContext) throws {
guard let accountDataFromDb = AccountDataHandler.shared.getAccountData(accountId: accountId, modelContext: modelContext) else {
return
}
for status in statuses {
guard self.getViewedStatus(accountId: accountId, statusId: status.id, modelContext: modelContext) == nil else {
continue
}
let viewedStatus = ViewedStatus(id: status.id, reblogId: status.reblog?.id, date: Date())
modelContext.insert(viewedStatus)
viewedStatus.pixelfedAccount = accountDataFromDb
accountDataFromDb.viewedStatuses.append(viewedStatus)
}
try modelContext.save()
}
/// Check if given status (real picture) has been already visible on the timeline (during last month).
func hasBeenAlreadyOnTimeline(accountId: String, status: Status, modelContext: ModelContext) -> Bool {
guard let reblog = status.reblog else {
return false
}
do {
let reblogId = reblog.id
var fetchDescriptor = FetchDescriptor<ViewedStatus>(
predicate: #Predicate { $0.pixelfedAccount?.id == accountId && $0.id != status.id && ($0.id == reblogId || $0.reblogId == reblogId) }
)
fetchDescriptor.fetchLimit = 1
fetchDescriptor.includePendingChanges = true
guard let first = try modelContext.fetch(fetchDescriptor).first else {
return false
}
if first.reblogId == nil {
return true
}
if first.id != status.id {
return true
}
return false
} catch {
CoreDataError.shared.handle(error, message: "Error during fetching viewed statuses (hasBeenAlreadyOnTimeline).")
return false
}
}
/// Mark to delete statuses older then one month.
func deleteOldViewedStatuses(modelContext: ModelContext) throws {
let oldViewedStatuses = self.getOldViewedStatuses(modelContext: modelContext)
for status in oldViewedStatuses {
modelContext.delete(status)
}
try modelContext.save()
}
private func getViewedStatus(accountId: String, statusId: String, modelContext: ModelContext) -> ViewedStatus? {
do {
var fetchDescriptor = FetchDescriptor<ViewedStatus>(
predicate: #Predicate { $0.id == statusId && $0.pixelfedAccount?.id == accountId }
)
fetchDescriptor.fetchLimit = 1
fetchDescriptor.includePendingChanges = true
return try modelContext.fetch(fetchDescriptor).first
} catch {
CoreDataError.shared.handle(error, message: "Error during fetching viewed statuses (getOldViewedStatuses).")
return nil
}
}
private func getOldViewedStatuses(modelContext: ModelContext) -> [ViewedStatus] {
guard let date = Calendar.current.date(byAdding: .month, value: -1, to: Date()) else {
return []
}
do {
var fetchDescriptor = FetchDescriptor<ViewedStatus>(
predicate: #Predicate { $0.date < date }
)
fetchDescriptor.includePendingChanges = true
return try modelContext.fetch(fetchDescriptor)
} catch {
CoreDataError.shared.handle(error, message: "Error during fetching viewed statuses (getOldViewedStatuses).")
return []
}
}
}