import Foundation
import Observation
import OSLog

private let feedLogger = Logger(subsystem: "com.treyt.mlbTVOS", category: "Feed")

private func logFeed(_ message: String) {
    feedLogger.debug("\(message, privacy: .public)")
    print("[Feed] \(message)")
}

enum FeedItemType: Sendable {
    case news
    case transaction
    case scoring
}

struct FeedItem: Identifiable, Sendable {
    let id: String
    let type: FeedItemType
    let title: String
    let subtitle: String
    let teamCode: String?
    let timestamp: Date
}

@Observable
@MainActor
final class FeedViewModel {
    var items: [FeedItem] = []
    var isLoading = false

    @ObservationIgnored
    private var refreshTask: Task<Void, Never>?

    private let webService = MLBWebDataService()

    func loadFeed() async {
        isLoading = true
        logFeed("loadFeed start")

        async let newsTask = webService.fetchNewsHeadlines()
        async let transactionsTask = webService.fetchTransactions()

        let news = await newsTask
        let transactions = await transactionsTask

        var allItems: [FeedItem] = []

        // News
        for headline in news {
            allItems.append(FeedItem(
                id: "news-\(headline.id)",
                type: .news,
                title: headline.title,
                subtitle: headline.summary,
                teamCode: nil,
                timestamp: headline.timestamp
            ))
        }

        // Transactions
        for tx in transactions {
            allItems.append(FeedItem(
                id: "tx-\(tx.id)",
                type: .transaction,
                title: tx.description,
                subtitle: tx.type,
                teamCode: tx.teamCode.isEmpty ? nil : tx.teamCode,
                timestamp: tx.date
            ))
        }

        // Sort reverse chronological
        items = allItems.sorted { $0.timestamp > $1.timestamp }
        isLoading = false
        logFeed("loadFeed complete items=\(items.count)")
    }

    func startAutoRefresh() {
        stopAutoRefresh()
        refreshTask = Task { [weak self] in
            while !Task.isCancelled {
                try? await Task.sleep(for: .seconds(300))
                guard !Task.isCancelled, let self else { break }
                await self.loadFeed()
            }
        }
    }

    func stopAutoRefresh() {
        refreshTask?.cancel()
        refreshTask = nil
    }
}