Messages Data Source

Swift Chat - 4 - Data Source.swift

extension MessagingDataSource: UITableViewDataSource {
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return messages.count
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let message = messages[indexPath.row]
        let identifier = cellIdentifier(for: message)
        let cell = tableView.dequeueReusableCell(withIdentifier: identifier, for: indexPath) as! MessageCell
        cell.message = message.text
        return cell
    }
    
    private func cellIdentifier(for message: Message) -> String {
        switch communicationDirection(for: message) {
        case .received:
            return receivedMessageCellIdentifier
        case .sent:
            return sentMessageCellIdentifer
        }
    }
    
    private func communicationDirection(for message: Message) -> Message.CommunicationDirection {
        if message.senderId == userId {
            return .received
        } else {
            return .sent
        }
    }
}