using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;
using System.Text.Json;

namespace spplus;

public static class ExportUtility
{
    private sealed class ConfigurationExport
    {
        public List<Sport> Sports { get; set; } = [];
        public int[] NumCoursesPerSemester { get; set; } = [];
    }

    public static void ExportToCSV(string filepath)
    {
        char separator = ',';
        string header = $"SchuelerID{separator}Sem1{separator}Sem2{separator}Sem3{separator}Sem4";
        string output = header + "\n";
        foreach (var student in Settings.Instance.Students)
        {
            output += $"{student.ID}{separator}{student.Result[0]}{separator}{student.Result[1]}{separator}{student.Result[2]}{separator}{student.Result[3]}\n";
        }
        
        File.WriteAllText(filepath, output);
    }

    private sealed class ResultExportEntry
    {
        public int Semester { get; set; }
        public string SportName { get; set; } = string.Empty;
        public List<string> Students { get; set; } = new();
    }

    public static void ExportResultsToJson(string filepath)
    {
        var list = CourseCrafter.GeneratedCourses
            .Select(g => new ResultExportEntry
            {
                Semester = g.Semester,
                SportName = g.Instance.Sport.Name,
                Students = g.Instance.Students.ToList()
            })
            .ToList();

        var json = JsonSerializer.Serialize(list, new JsonSerializerOptions { WriteIndented = true });
        File.WriteAllText(filepath, json);
    }

    public static void ExportConfigurationToJson(string filepath)
    {
        var export = new ConfigurationExport
        {
            Sports = Settings.Instance.Sports,
            NumCoursesPerSemester = Settings.Instance.NumCoursesPerSemester
        };

        var json = JsonSerializer.Serialize(export, new JsonSerializerOptions
        {
            WriteIndented = true
        });

        File.WriteAllText(filepath, json);
    }
}