another.im-ios/ConversationsClassic/AppData/Store/MessagesStore.swift

import AVFoundation
import Combine
import Foundation
import GRDB
import Photos

@MainActor
final class MessagesStore: ObservableObject {
    @Published private(set) var messages: [Message] = []
    @Published var replyText = ""

    private(set) var roster: Roster
    private let client: Client

    private var messagesCancellable: AnyCancellable?

    init(roster: Roster, client: Client) {
        self.client = client
        self.roster = roster
        subscribe()
    }
}

extension MessagesStore {
    func sendMessage(_ message: String) {
        Task {
            var msg = Message.blank
            msg.from = roster.bareJid
            msg.to = roster.contactBareJid
            msg.body = message

            // store as pending on db, and send
            do {
                try await msg.save()
                try await client.sendMessage(msg)
                try await msg.setStatus(.sent)
            } catch {
                try? await msg.setStatus(.error)
            }
        }
    }

    func sendContact(_ jidStr: String) {
        sendMessage("contact:\(jidStr)")
    }

    func sendLocation(_ lat: Double, _ lon: Double) {
        sendMessage("geo:\(lat),\(lon)")
    }
}

private extension MessagesStore {
    func subscribe() {
        messagesCancellable = ValueObservation.tracking(Message
            .filter(
                (Column("to") == roster.bareJid && Column("from") == roster.contactBareJid) ||
                    (Column("from") == roster.bareJid && Column("to") == roster.contactBareJid)
            )
            .order(Column("date").desc)
            .fetchAll
        )
        .publisher(in: Database.shared.dbQueue, scheduling: .immediate)
        .receive(on: DispatchQueue.main)
        .sink { _ in
        } receiveValue: { [weak self] messages in
            self?.messages = messages
        }
    }
}