import Foundation
import SwiftUI

@MainActor
class DataService: ObservableObject {
    
    @Published var partners: [Partner] = []
    @Published var depots: [Depot] = []
    @Published var datapoints: [Depotstand] = []
    @Published var sortedDatapoints: [Depotstand] = []
    @Published var depot: Depot = Depot(id: 0, name: "", type: "")
    
    let prefixURL: String = "https://REST-API-LINK"
    
    let dateFormatter: DateFormatter = {
        let formatter = DateFormatter()
        formatter.dateFormat = "yyyy-MM-dd"
        return formatter
    }()
    
    //MARK: - Diverse Daten-Funktionen
     
    func sortDatapoints(_ depot: Depot) /*-> [Depotstand]*/ {
        var sortedDatapoints: [Depotstand] = []
        
        if let datapoints = depot.datapoints {
            sortedDatapoints = datapoints.sorted{
                $0.date.compare($1.date) == .orderedDescending
            }
            sortedDatapoints = sortedDatapoints.sorted{
                $0.id > $1.id
            }
        }
        
        self.sortedDatapoints = sortedDatapoints
        //return sortedDatapoints
    }
    
    
    //MARK: - REST-API Funktionen
    
    func createDepotStand(parameters: [String: Any]) async {
        let encoded = try! JSONSerialization.data(withJSONObject: parameters)
        var request = URLRequest(url: URL(string: prefixURL + "REST-API-LINK")!); request.httpMethod = "POST"; request.setValue("application/json", forHTTPHeaderField: "Content-Type")
        do {
            let (_, _) = try await URLSession.shared.upload(for: request, from: encoded)
        } catch let JsonError { print("createDepotstand failed:", JsonError) }
    }
     
    func readDepotstandAll() async throws {
        let decoder = JSONDecoder()
        decoder.dateDecodingStrategy = .formatted(self.dateFormatter)
        let (data, _) = try await URLSession.shared.data(from: URL(string: prefixURL + "REST-API-LINK")!)
        
        do {
            self.datapoints = try decoder.decode([Depotstand].self, from: data)
        } catch let JsonError {
            print("fetch JSON error: ", JsonError.localizedDescription)
            print("Das Problem: ", JsonError)
        }
    }
    
    func readDepot(id: Int) async {
        let decoder = JSONDecoder()
        decoder.dateDecodingStrategy = .formatted(self.dateFormatter)        
        do {
            let (data, _) = try await URLSession.shared.data(from: URL(string: prefixURL + "REST-API-LINK")!)
            self.depot = try decoder.decode(Depot.self, from: data)
            sortDatapoints(self.depot)
        } catch { print("readDepot failed") }
    }
}