using System;

using System.Collections.Generic;

using System.Linq;

using System.IO;

using System.ComponentModel;

using Toolbox.Core;

namespace MapStudio.UI

{

/// <summary>

/// Translation handler for translating given keys into localized text.

/// </summary>

public class TranslationSource : INotifyPropertyChanged

{

private static readonly TranslationSource instance = new TranslationSource();

private Dictionary<string, string> Translation = new Dictionary<string, string>();

/// <summary>

/// The language key to determine what language file to use.

/// </summary>

public static string LanguageKey = "English";

/// <summary>

/// The instance of the translation source.

/// </summary>

public static TranslationSource Instance

{

get { return instance; }

}

/// <summary>

/// Checks if the translation lookup has a given key or not.

/// </summary>

public static bool HasKey(string key) {

if (key == null) return false;

return Instance.Translation.ContainsKey(key);

}

/// <summary>

/// Returns the localized text from a given key.

/// </summary>

public static string GetText(string key) {

return Instance[key];

}

/// <summary>

/// Returns the localized text from a given key.

/// </summary>

public string this[string key]

{

get

{

//Return the key by itself if not contained in the translation list.

if (!HasKey(key))

return key;

return Translation[key];

}

}

/// <summary>

/// Gets a list of language file paths in the "Languages" folder.

/// </summary>

public static List<string> GetLanguages()

{

List<string> languages = new List<string>();

foreach (var file in Directory.GetDirectories("Languages")) {

languages.Add(new DirectoryInfo(file).Name);

}

return languages;

}

/// <summary>

/// Updates the current language and reloads the translation list.

/// </summary>

public void Update(string key)

{

LanguageKey = key;

Reload();

}

/// <summary>

// Reloads the translation list with the current language key.

/// </summary>

public void Reload() {

Translation.Clear();

foreach (var file in Directory.GetFiles($"{Runtime.ExecutableDir}/Languages/{LanguageKey}"))

Load(file);

PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(string.Empty));

}

/// <summary>

// Loads the language file and adds the keys with localized text to the translation lookup.

/// </summary>

public void Load(string fileName)

{

using (var reader = new StreamReader(fileName))

{

while (!reader.EndOfStream)

{

string line = reader.ReadLine();

if (line.StartsWith("#") || !(line.Contains("-") || line.Contains(":"))) // If this line contains nothing of value skip it

continue;

if (line.Contains(":") && !line.Contains("-")) // If this line indicates it's a text block, read out the text block. Prefer text lines.

{

var key = line.Split(':')[0].Trim();

var value = ReadTextBlock(reader);

if (!Translation.ContainsKey(key))

Translation.Add(key, value);

else

Translation[key] = value;

}

else // This must be a text line translation. Process it as such.

{

var entries = line.Split('-');

//Remove comments at end if used

var value = entries[1].Split('#').FirstOrDefault().Trim();

var key = entries[0].Trim();

if (!Translation.ContainsKey(key))

Translation.Add(key, value);

else

Translation[key] = value;

}

}

}

}

private string ReadTextBlock(StreamReader reader)

{

string text = "";

string line = "";

while (!reader.EndOfStream)

{

line = reader.ReadLine();

if (line.Split('#')[0] == ":")

break;

text += line + "\n";

}

text.Trim();

return text;

}

public event PropertyChangedEventHandler PropertyChanged;

}

}