namespace JetbrainsConfig;

using System;
using System.IO;

class Prop
{
    string key = "";
    string value = "";
    bool line = false;

    public string Key
    {
        get => key;
        set => key = value ?? throw new ArgumentNullException(nameof(value));
    }

    public string Value
    {
        get => value;
        set => this.value = value ?? throw new ArgumentNullException(nameof(value));
    }

    public bool Line
    {
        get => line;
        set => line = value;
    }

    public override string ToString()
    {
        if (line)
        {
            return key;
        }
        return key + "=" + value;
    }
}
public class Properties
{
    string path;
    List<Prop> props = new List<Prop>();
    Dictionary<string, int> dict = new Dictionary<string, int>();

    public Properties(string filename)
    {
        this.path = filename ?? throw new ArgumentNullException(nameof(filename));
        string line;
        int lineLen = -1;
        using (StreamReader sr = new StreamReader(filename))
        {
            while (sr.Peek() >= 0)
            {
                var prop = new Prop();
                line = sr.ReadLine();
                lineLen++;
                if (string.IsNullOrEmpty(line) || line.StartsWith('#'))
                {
                    prop.Key = line;
                    prop.Line = true;
                    props.Add(prop);
                    continue;
                }
                var strings = line.Split('=');
                prop.Key = strings[0];
                prop.Value = strings[1];
                prop.Line = false;
                props.Add(prop);
                dict.Add(strings[0], lineLen);
            }
        }
    }

    public void Add(string key, string value)
    {
        if (dict.ContainsKey(key))
        {
            Prop p = props[dict[key]];
            p.Value = value;
        }
        else
        {
            props.Add(new Prop() { Key = key, Value = value});
        }
    }

    public void Save()
    {
        if (File.Exists(path))
        {
            File.Delete(path);
        }
        FileStream fileStream = File.Create(path);
        StreamWriter sw = new StreamWriter(fileStream);
        foreach (Prop p in props)
        {
            sw.WriteLine(p.ToString());
        }
        sw.Close();
        fileStream.Close();
        
    }

}