//
//  ChatsViewModel.swift
//  Training
//
//  Created by mrtuxa on 27.08.22.
//

import Foundation


class ChatsViewModel: ObservableObject {

    @Published var chats = Chat.sampleChat

    func getSortedFilteredChats(query: String) -> [Chat] {
        let sortedChats = chats.sorted {
            guard let date1 = $0.messages.last?.date else {
                return false
            }
            guard let date2 = $1.messages.last?.date else {
                return false
            }
            return date1 > date2
        }

        if query == "" {
            return sortedChats
        }
        return sortedChats.filter {
            $0.person.name.lowercased().contains(query.lowercased())
        }
    }

    func getSectionMessages(for chat: Chat) -> [[Message]] {
        var res = [[Message]]()
        var tmp = [Message]()
        for message in chat.messages {
            if let firstMessage = tmp.first {
                let daysBetween = firstMessage.date.daysBetween(date: message.date)
                if daysBetween >= 1 {
                    res.append(tmp)
                    tmp.removeAll()
                    tmp.append(message)
                } else {
                    tmp.append(message)
                }
            } else {
                tmp.append(message)
            }
        }
        res.append(tmp)
        return res
    }

    func markAsUnread(_ newValue: Bool, chat: Chat) {
        if let index = chat.messages.firstIndex(where: { $0.id == chat.id }) {
            chats[index].hasUnreadMessage = newValue
        }
    }

    func sendMessage(_ text: String, in chat: Chat) -> Message? {
        if let index = chats.firstIndex { $0.id == chat.id  } {
            let message = Message(text, type: .Sent)
            chats[index].messages.append(message)
            return message
        }
        return nil
    }
}