//
//  PatientMonthlyHistoryViewModel.swift
//  medmap
//

import Foundation
import Combine
import SwiftUI
@MainActor
final class PatientMonthlyHistoryViewModel: ViewModel {

    @Published private(set) var history: PatientMonthlyHistoryResponse?
    @Published private(set) var errorMessage: String?

    private let api: MedMapAPI = DIContainer.shared.resolve()
    private let calendar = Calendar(identifier: .gregorian)
    private var selectedMonth = Date.now

    

    func loadHistory() async {
        guard !isLoading else { return }

        isLoading = true
        errorMessage = nil
        defer { isLoading = false }

        do {
            history = try await api.getMyMonthlyHistory(date: formattedMonth)
        } catch {
            errorMessage = "Nao foi possivel carregar o historico mensal."
            fluxlog("Monthly history load failed: \(error.localizedDescription)")
        }
    }

    func showPreviousMonth() async {
        selectedMonth = calendar.date(byAdding: .month, value: -1, to: selectedMonth) ?? selectedMonth
        await loadHistory()
    }

    func showNextMonth() async {
        selectedMonth = calendar.date(byAdding: .month, value: 1, to: selectedMonth) ?? selectedMonth
        await loadHistory()
    }

    private var formattedMonth: String {
        let formatter = DateFormatter()
        formatter.locale = Locale(identifier: "en_US_POSIX")
        formatter.dateFormat = "yyyy-MM-dd"
        return formatter.string(from: selectedMonth)
    }
}