ex-int-02-meet-the-teacher/MeetTheTeacher/Program.cs

using System.Text;
using MeetTheTeacher.Export;
using MeetTheTeacher.Import;
using MeetTheTeacher.Model;
using Spectre.Console;

Console.OutputEncoding = Encoding.UTF8;

Clear();
AnsiConsole.Markup("[orange3]Press any key to load HTL-Leonding teacher data[/] ");
Console.ReadKey();

// data loading
bool loadRealData = AskForDataToUse();
// wrapping IEnumerable in List, because we will iterate multiple times
var data = new List<Teacher>(LoadData(loadRealData));
var tableGenerator = new SpectreTableExporter();
tableGenerator.Export(data, string.Empty);

// fake loading
Clear();
await DisplayFakeProgress();
Clear();
AnsiConsole.Write(tableGenerator.Table);
PrintStatistics(data);

// user input
WriteRule("Sort Order");
var order = AskForSortOrder();
WriteRule("Export Format");
var format = AskForExportFormat();
WriteRule("File Name");
string fileName = AnsiConsole.Ask<string>("Which [blue]file name[/] should be used?");

// export
var exporter = new Exporter(order, format, new DefaultExporterProvider());
exporter.Export(fileName, data);

// done
WriteRule(string.Empty);
AnsiConsole.Write(new FigletText("All Done!").Centered().Color(Color.Green));
DrawDog();

return;

static void Clear()
{
    Console.Clear();
    AnsiConsole.Write(new FigletText("Teacher Data").Centered().Color(Color.Blue));
}

static void WriteRule(string text)
{
    AnsiConsole.Write(new Rule($"[blue]{text}[/]").LeftJustified());
}

static IEnumerable<Teacher> LoadData(bool realData)
{
    string generalDataFilePath = "Data/teachers.csv";
    string businessCardDataFilePath = "Data/teachers-with-business-card.csv";
    
    if (!File.Exists(generalDataFilePath))
    {
        AnsiConsole.MarkupLine($"[red]Error:[/] File '{generalDataFilePath}' not found");
        return [];
    }
    
    ITeacherDataImporter importer = realData 
        ? new TeacherDataCsvImporter(generalDataFilePath, businessCardDataFilePath)
        : new TeacherDataFakeImporter();
    
    return importer.LoadTeacherData();
}

static Task DisplayFakeProgress()
{
    const double Increase = 4.5;
    const double ReducedIncrease = Increase * 0.8D;

    return AnsiConsole.Progress()
                      .StartAsync(async ctx =>
                      {
                          // we are actually already done, but want to fake some complex operation
                          // to have the user appreciate the hard work our application is doing :)
                          var task1 = ctx.AddTask("[green]Loading Data[/]");
                          var task2 = ctx.AddTask("[green]Processing Data[/]");

                          while (!ctx.IsFinished)
                          {
                              task1.Increment(Increase);
                              task2.Increment(ReducedIncrease);
                              await Task.Delay(TimeSpan.FromMilliseconds(125));
                          }
                      });
}

static void PrintStatistics(IReadOnlyCollection<Teacher> teachers)
{
    var hasConsultingHours = 0;
    var hasBusinessCard = 0;
    foreach (var teacher in teachers)
    {
        if (teacher.ConsultingHour != null)
        {
            hasConsultingHours++;
        }
        
        if (teacher is TeacherWithBusinessCard)
        {
            hasBusinessCard++;
        }
    }

    double total = teachers.Count;
    var cPercentage = (int) (hasConsultingHours / total * 100);
    int ncPercentage = 100 - cPercentage;
    var bPercentage = (int) (hasBusinessCard / total * 100);

    AnsiConsole.Write(new BarChart()
                      .Width(60)
                      .Label($"[blue underline]Statistics ({total:F0} teachers)[/]")
                      .CenterLabel()
                      .AddItem("Has consulting hour", cPercentage, Color.Green)
                      .AddItem("Has no consulting hour", ncPercentage, Color.Red)
                      .AddItem("Has business card", bPercentage, Color.Purple));
}

static SortOrder AskForSortOrder()
{
    var options = new Dictionary<string, SortOrder>
    {
        ["Name Asc."] = SortOrder.ByNameAsc,
        ["Name Desc."] = SortOrder.ByNameDesc,
        ["Hour Asc."] = SortOrder.ByHourAsc,
        ["Hour Desc."] = SortOrder.ByHourDesc,
        ["Room"] = SortOrder.Room
    };
    string order = AnsiConsole.Prompt(new SelectionPrompt<string>()
                                      .Title("How do you wish to [blue]sort[/] the data?")
                                      .PageSize(3)
                                      .MoreChoicesText("[grey](Move up and down to reveal more options)[/]")
                                      .AddChoices(options.Keys));

    AnsiConsole.MarkupLine($"Selected: [green]{order}[/]");

    return options[order];
}

static ExportFormat AskForExportFormat()
{
    const string Csv = "Csv";
    const string Html = "Html";
    string dataToUse = AnsiConsole.Prompt(new SelectionPrompt<string>()
                                          .Title("Do you want to load [blue]real[/] or [blue]sample[/] data?")
                                          .AddChoices(Csv, Html));

    AnsiConsole.MarkupLine($"Selected: [green]{dataToUse}[/]");

    return dataToUse == Csv ? ExportFormat.Csv : ExportFormat.Html;
}

static bool AskForDataToUse()
{
    const string Real = "Real";
    string dataToUse = AnsiConsole.Prompt(new SelectionPrompt<string>()
                                          .Title("Do you want to load [blue]real[/] or [blue]sample[/] data?")
                                          .AddChoices(Real, "Sample"));

    AnsiConsole.MarkupLine($"Selected: [green]{dataToUse}[/]");

    return dataToUse == Real;
}

static void DrawDog()
{
    var image = new CanvasImage("happy-dog.png");
    image.MaxWidth(36);
    AnsiConsole.Write(image);
}