import Foundation
import OSLog

private let webDataLogger = Logger(subsystem: "com.treyt.mlbTVOS", category: "WebData")

private func logWebData(_ message: String) {
    webDataLogger.debug("\(message, privacy: .public)")
    print("[WebData] \(message)")
}

// MARK: - Models

struct NewsHeadline: Identifiable, Sendable {
    let id: String
    let title: String
    let summary: String
    let timestamp: Date
    let imageURL: URL?
}

struct InjuryReport: Identifiable, Sendable {
    let id: String
    let teamCode: String
    let playerName: String
    let position: String
    let status: String  // "10-Day IL", "60-Day IL", "Day-to-Day"
    let date: Date
    let notes: String
}

struct Transaction: Identifiable, Sendable {
    let id: String
    let teamCode: String
    let description: String
    let date: Date
    let type: String  // "Trade", "DFA", "Call-Up", "Placed on IL"
}

struct LeagueLeader: Identifiable, Sendable {
    let id: String
    let rank: Int
    let playerName: String
    let teamCode: String
    let value: String
    let personId: Int?
}

struct LeaderCategory: Identifiable, Sendable {
    let id: String
    let name: String
    let leaders: [LeagueLeader]
}

// MARK: - Service

actor MLBWebDataService {
    private let statsAPI = MLBStatsAPI()
    private let session: URLSession

    init() {
        let config = URLSessionConfiguration.default
        config.timeoutIntervalForRequest = 15
        session = URLSession(configuration: config)
    }

    // MARK: - League Leaders (via Stats API)

    func fetchLeagueLeaders() async throws -> [LeaderCategory] {
        let categories = [
            ("homeRuns", "Home Runs"),
            ("battingAverage", "Batting Average"),
            ("runsBattedIn", "RBI"),
            ("earnedRunAverage", "ERA"),
            ("strikeouts", "Strikeouts"),
            ("wins", "Wins"),
            ("saves", "Saves"),
            ("stolenBases", "Stolen Bases"),
            ("onBasePlusSlugging", "OPS"),
            ("walksHitsPerInningPitched", "WHIP"),
        ]

        var results: [LeaderCategory] = []

        for (code, name) in categories {
            let url = URL(string: "https://statsapi.mlb.com/api/v1/stats/leaders?leaderCategories=\(code)&season=\(currentSeason)&limit=5&sportId=1")!
            logWebData("fetchLeagueLeaders category=\(code)")

            do {
                let (data, _) = try await session.data(from: url)
                let response = try JSONDecoder().decode(LeaderResponse.self, from: data)

                if let category = response.leagueLeaders?.first {
                    let leaders = (category.leaders ?? []).prefix(5).enumerated().map { index, leader in
                        LeagueLeader(
                            id: "\(code)-\(index)",
                            rank: leader.rank ?? (index + 1),
                            playerName: leader.person?.fullName ?? "Unknown",
                            teamCode: leader.team?.abbreviation ?? "",
                            value: leader.value ?? "",
                            personId: leader.person?.id
                        )
                    }
                    results.append(LeaderCategory(id: code, name: name, leaders: Array(leaders)))
                }
            } catch {
                logWebData("fetchLeagueLeaders FAILED category=\(code) error=\(error)")
            }
        }

        logWebData("fetchLeagueLeaders complete categories=\(results.count)")
        return results
    }

    // MARK: - News Headlines (from MLB.com)

    func fetchNewsHeadlines() async -> [NewsHeadline] {
        let url = URL(string: "https://statsapi.mlb.com/api/v1/news?sportId=1")!
        logWebData("fetchNewsHeadlines")

        do {
            let (data, _) = try await session.data(from: url)
            let response = try JSONDecoder().decode(NewsResponse.self, from: data)

            let headlines = (response.articles ?? []).prefix(15).map { article in
                NewsHeadline(
                    id: article.slug ?? UUID().uuidString,
                    title: article.headline ?? "Untitled",
                    summary: article.subhead ?? "",
                    timestamp: ISO8601DateFormatter().date(from: article.date ?? "") ?? Date(),
                    imageURL: article.image?.cuts?.first?.src.flatMap(URL.init)
                )
            }
            logWebData("fetchNewsHeadlines success count=\(headlines.count)")
            return Array(headlines)
        } catch {
            logWebData("fetchNewsHeadlines FAILED error=\(error)")
            return []
        }
    }

    // MARK: - Transactions (from Stats API)

    func fetchTransactions() async -> [Transaction] {
        let formatter = DateFormatter()
        formatter.dateFormat = "MM/dd/yyyy"
        let today = formatter.string(from: Date())
        let weekAgo = formatter.string(from: Calendar.current.date(byAdding: .day, value: -7, to: Date())!)

        let url = URL(string: "https://statsapi.mlb.com/api/v1/transactions?startDate=\(weekAgo)&endDate=\(today)&sportId=1")!
        logWebData("fetchTransactions from=\(weekAgo) to=\(today)")

        do {
            let (data, _) = try await session.data(from: url)
            let response = try JSONDecoder().decode(TransactionResponse.self, from: data)

            let transactions = (response.transactions ?? []).prefix(30).enumerated().map { index, tx in
                Transaction(
                    id: "\(tx.id ?? index)",
                    teamCode: tx.team?.abbreviation ?? "",
                    description: tx.description ?? "",
                    date: ISO8601DateFormatter().date(from: tx.date ?? "") ?? Date(),
                    type: tx.typeDesc ?? "Transaction"
                )
            }
            logWebData("fetchTransactions success count=\(transactions.count)")
            return Array(transactions)
        } catch {
            logWebData("fetchTransactions FAILED error=\(error)")
            return []
        }
    }

    private var currentSeason: Int {
        Calendar.current.component(.year, from: Date())
    }
}

// MARK: - API Response Models

private struct LeaderResponse: Codable {
    let leagueLeaders: [LeaderCategoryResponse]?
}

private struct LeaderCategoryResponse: Codable {
    let leaderCategory: String?
    let leaders: [LeaderEntry]?
}

private struct LeaderEntry: Codable {
    let rank: Int?
    let value: String?
    let person: PersonRef?
    let team: TeamRef?
}

private struct PersonRef: Codable {
    let id: Int?
    let fullName: String?
}

private struct TeamRef: Codable {
    let id: Int?
    let abbreviation: String?
}

private struct NewsResponse: Codable {
    let articles: [NewsArticle]?
}

private struct NewsArticle: Codable {
    let slug: String?
    let headline: String?
    let subhead: String?
    let date: String?
    let image: NewsImage?
}

private struct NewsImage: Codable {
    let cuts: [NewsImageCut]?
}

private struct NewsImageCut: Codable {
    let src: String?
}

private struct TransactionResponse: Codable {
    let transactions: [TransactionEntry]?
}

private struct TransactionEntry: Codable {
    let id: Int?
    let description: String?
    let date: String?
    let typeDesc: String?
    let team: TeamRef?
}