//
//  SeismicNetworkViewModel.swift
//  Earthquake Network
//
//  Created by Andrea Busi on 15/03/21.
//  Copyright © 2021 Earthquake Network. All rights reserved.
//

import Foundation


struct SeismicNetworkViewModel {
    
    var place: String
    var network: String
    var isPreliminary: Bool
    var magnitude: String
    var depth: String
    var time: String
    var distance: String
    var coordinate: String
    var population: String
    var smartphones: String
    var users: String
    
    // MARK: - Init
    
    init(seismic: EQNSisma) {
        self.place = seismic.place
        self.network = seismic.provider
        
        let isPreliminary = seismic.preliminary.intValue > 0
        self.isPreliminary = isPreliminary
        if isPreliminary {
            let lowerValue = seismic.magnitude.doubleValue - seismic.magnitudeRange.doubleValue/2.0
            let upperValue = seismic.magnitude.doubleValue + seismic.magnitudeRange.doubleValue/2.0
            self.magnitude = String(format: "%.1f-%.1f\(seismic.magnitudeType)", lowerValue, upperValue)
            self.depth = ""
        } else {
            self.magnitude = String(format: "%.1f%@", seismic.magnitude.doubleValue, seismic.magnitudeType)
            self.depth = String(format: "%@: %.1f km", NSLocalizedString("Profondità", comment: ""), seismic.depth.doubleValue)
        }
        
        // we need to check agains null values, because sometimes WS returns invalid dates
        if let date = seismic.date {
            let formattedDate = EQNUtility.formattedDate(from: date)
            let time = EQNUtility.formattedString(forTimeDifference: Int(seismic.timeDifference))
            self.time = "\(formattedDate) - \(time)"
        } else {
            self.time = "no time available"
        }
        
        // distance
        let distanceRounded = Int(round(seismic.userDistance))
        self.distance = "\(distanceRounded) km \(NSLocalizedString("dalla tua posizione", comment: ""))"
        let coordinateText = EQNUtility.coordinateString(coordinate: seismic.coordinate.coordinate)
        self.coordinate = "\(coordinateText)"
        
        let population = Self.formatPopulation(seismic.population100km)
        self.population = "\(population) \(NSLocalizedString("share_radius100", comment: ""))"
        
        if seismic.smartphoneNumber.intValue > 0 {
            self.smartphones = String(format: NSLocalizedString("official_smartphones", comment: ""), seismic.smartphoneNumber)
        } else {
            self.smartphones = ""
        }
        if seismic.userNumber.intValue > 0 {
            self.users = String(format: NSLocalizedString("official_reports", comment: ""), seismic.userNumber)
        } else {
            self.users = ""
        }
    }
    
    // MARK: - Private
    
    /// Format population value (ex. 1.5M, 2.4k)
    private static func formatPopulation(_ population: Double) -> String {
        var populationString = ""
        if population > 999_999 {
            let roundedPopulation = round(population / 100_000) / 10
            populationString = "\(roundedPopulation)M"
        } else if population > 999 {
            let roundedPopulation = round(population / 100) / 10
            populationString = "\(roundedPopulation)K"
        } else {
            let roundedPopulation = round(population)
            populationString = "\(roundedPopulation)"
        }
        return populationString
    }
}