using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

​

public class Program

{

    public static void Main()

    {       

        var tbl = new MarkdownTable()

            .AddColumn("City/Date")

            .AddColumns(Enumerable.Range(0,5).Select(x => DateTime.Now.AddDays(x).ToString("yyyy-MM-dd")));

        var cities = new []{"Tel Aviv", "New York", "Washington", "Madrid", "Berlin", "London"};

        foreach (var city in cities)

        {

            var temp = Enumerable.Range(0,5).Select(_ => $"{Random.Shared.Next(0, 41)} C");

​

            tbl.AddRow(new Row().AddValue(city).AddValues(temp));

        }

​

        Console.WriteLine(tbl.ToString());

    }

}

​

public class MarkdownTable

{

    private readonly List<Column> _columns = [];

​

    private readonly List<string[]> _rows = [];

​

    public MarkdownTable AddColumn(string columnName, Alignment alignment = Alignment.Left)

    {

        if (_rows.Count != 0)

            throw new Exception("Can't add columns after rows were added");

​

        _columns.Add(new Column { Heading = columnName, Alignment = alignment });

​

        return this;

    }

​

    public MarkdownTable AddColumns(params string[] columns)

    {

        if (_rows.Count != 0)

            throw new Exception("Can't add columns after rows were added");

​

        _columns.AddRange(columns.Select(columnName => new Column { Heading = columnName, Alignment = Alignment.Left }));

​

        return this;

    }

​

    public MarkdownTable AddColumns(IEnumerable<string> columns)

    {

        if (_rows.Count != 0)

            throw new Exception("Can't add columns after rows were added");

​

        _columns.AddRange(columns.Select(columnName => new Column { Heading = columnName, Alignment = Alignment.Left }));

​

        return this;

    }

​

    public MarkdownTable AddColumn(Column column)

    {

        if (_rows.Count != 0)

            throw new Exception("Can't add columns after rows were added");

​

        _columns.Add(column);

​

        return this;

    }

​

    public MarkdownTable AddColumn(IEnumerable<Column> column)

    {

        if (_rows.Count != 0)

            throw new Exception("Can't add columns after rows were added");

​

        _columns.AddRange(column);

​

        return this;

    }

​

    public MarkdownTable AddRow(params string[] values)

    {

        if (values.Length != _columns.Count)

            throw new Exception("You can not add a row with different length than the amount of columns");

​

        _rows.Add(values); 

        return this;

    }

​

    public MarkdownTable AddRows(IEnumerable<string[]> values)

    {

        foreach(var row in values)

            _rows.Add(row);

​

        return this;

    }

​

    public MarkdownTable AddRow(Row row)

    {

        if (row.Values.Count() != _columns.Count)

            throw new Exception("You can not add a row with different length than the amount of columns");

​

        _rows.Add(row.Values.ToArray());

​

        return this;

    }

​

    public MarkdownTable AddRows(IEnumerable<Row> rows)

    {

        foreach (var row in rows)

        {

            if (row.Values.Count() != _columns.Count)

                throw new Exception("You can not add a row with different length than the amount of columns");

​

            _rows.Add(row.Values.ToArray());

        }

​

        return this;

    }

​

    public override string ToString()

    {

        if (_columns.Count == 0)

        {

            throw new Exception("You are missing columns in your table");

        }

​

        var sb = new StringBuilder();

​

        var columnsLength = _columns

            .Select((column, i) => Math.Max(column.Heading.Length, _rows.Max(row => row[i].Length)))

            .ToArray();

​

        // put headers

        sb.Append("| ");

        for(var i = 0; i < _columns.Count; i++)

        {

            sb.Append(_columns[i].Heading.PadRight(columnsLength[i]));

            if (i < _columns.Count - 1)

            {

                sb.Append(" | ");

            }

        }

        sb.AppendLine(" |");

​

        // put split bar

        sb.Append('|');

        for (var i = 0; i < _columns.Count; i++)

        {

            var column = _columns[i];

​

            _ = column.Alignment switch

            {

                Alignment.Center => sb.Append(':'),

                _ => sb.Append('-')

            };

            sb.Append(Repeat("-",columnsLength[i]));

​

            _ = column.Alignment switch

            {

                Alignment.Center or Alignment.Right => sb.Append(':'),

                _ => sb.Append('-')

            };

​

            if (i < _columns.Count - 1)

            {

                sb.Append('|');

            }

        }

        sb.AppendLine("|");

​

        // put rows

        foreach (var row in _rows)

        {

            sb.Append("| ");

​

            for (var i = 0; i < _columns.Count; i++)

            {

                sb.Append(row[i].PadRight(columnsLength[i]));

                if (i < _columns.Count - 1)

                {

                    sb.Append(" | ");

                }

            }

​

            sb.AppendLine(" |");

        }

​

        return sb.ToString();

    }

​

    static string Repeat(string text, int times)

    {

        var sb = new StringBuilder();

        for (var i = 0; i < times; i++)

        {

            sb.Append(text);

        }

        return sb.ToString();

    }

​

    public void Clear()

    {

        _columns.Clear();

        _rows.Clear();

    }

}

​

public class Column

{

    public required string Heading { get; set; }

​

    public Alignment Alignment { get; set; } = Alignment.Left;

}

​

public class Row

{

    private List<string> _values = new List<string>();

    public IEnumerable<string> Values => _values;

​

    public Row AddValue(string value)

    {

        _values.Add(value);

        return this;

    }

​

    public Row AddValues(IEnumerable<string> values)

    {

        _values.AddRange(values);

        return this;

    }

}

​

public enum Alignment

{

    Left,

    Center,

    Right

}