aliasvault/apps/server/AliasVault.Client/Main/Models/Languages.cs

// <auto-generated />
// This file is auto-generated from core/models/src/defaults/Languages.ts
// Do not edit this file directly. Run 'core/models/build.sh' (or
// 'node core/models/scripts/generate-languages.cjs') to regenerate.

#nullable enable

namespace AliasVault.Client.Main.Models;

/// <summary>
/// Generic language reference shared across all AliasVault clients: maps a two-letter ISO 639-1
/// code to a flag, native label, and the region-variant locale codes that map onto it.
/// </summary>
public static class Languages
{
    /// <summary>
    /// Default ISO language code used as the universal fallback.
    /// </summary>
    public const string DefaultLanguageCode = "en";

    /// <summary>
    /// Known languages keyed by ISO 639-1 code, with a flag, native label, and the BCP-47
    /// region-variant locale codes (e.g. "en-US", "en-GB") that resolve onto the code.
    /// </summary>
    private static readonly (string Code, string Flag, string Label, string[] AlternativeCodes)[] Meta =
    [
        ("en", "🇺🇸", "English", ["en-US", "en-GB", "en-CA", "en-AU", "en-NZ", "en-IE", "en-ZA", "en-SG", "en-IN"]),
        ("nl", "🇳🇱", "Nederlands", ["nl-NL", "nl-BE"]),
        ("de", "🇩🇪", "Deutsch", ["de-DE", "de-AT", "de-CH", "de-LU", "de-LI"]),
        ("fr", "🇫🇷", "Français", ["fr-FR", "fr-CA", "fr-BE", "fr-CH", "fr-LU", "fr-MC"]),
        ("es", "🇪🇸", "Español", ["es-ES", "es-MX", "es-AR", "es-CO", "es-CL", "es-PE", "es-VE", "es-EC", "es-GT", "es-CU", "es-BO", "es-DO", "es-HN", "es-PY", "es-SV", "es-NI", "es-CR", "es-PA", "es-UY", "es-PR"]),
        ("it", "🇮🇹", "Italiano", ["it-IT", "it-CH", "it-SM", "it-VA"]),
        ("da", "🇩🇰", "Dansk", ["da-DK"]),
        ("fi", "🇫🇮", "Suomi", ["fi-FI"]),
        ("he", "🇮🇱", "עברית", ["he-IL"]),
        ("pl", "🇵🇱", "Polski", ["pl-PL"]),
        ("pt", "🇧🇷", "Português Brasileiro", ["pt-BR", "pt-PT"]),
        ("ro", "🇷🇴", "Română", ["ro-RO", "ro-MD"]),
        ("ru", "🇷🇺", "Русский", ["ru-RU", "ru-BY", "ru-KZ", "ru-UA"]),
        ("sv", "🇸🇪", "Svenska", ["sv-SE", "sv-FI"]),
        ("uk", "🇺🇦", "Українська", ["uk-UA"]),
        ("zh", "🇨🇳", "简体中文", ["zh-CN", "zh-SG", "zh-Hans", "zh-TW", "zh-HK", "zh-MO", "zh-Hant"]),
        ("ur", "🇵🇰", "اردو", ["ur-PK", "ur-IN"]),
        ("fa", "🇮🇷", "فارسی", ["fa-IR", "fa-AF"]),
    ];

    /// <summary>
    /// Normalize an app/UI language tag to a two-letter lowercase ISO code (e.g. "nl-NL" -> "nl").
    /// </summary>
    /// <param name="code">The language tag.</param>
    /// <returns>The two-letter lowercase code.</returns>
    public static string Normalize(string? code)
    {
        var value = code ?? string.Empty;
        return (value.Length >= 2 ? value.Substring(0, 2) : value).ToLowerInvariant();
    }

    /// <summary>
    /// Get the display label (flag + native name) for an ISO language code. Falls back to a globe
    /// flag and the raw code for unknown languages.
    /// </summary>
    /// <param name="code">The ISO language code (case-insensitive).</param>
    /// <returns>A display string such as "🇳🇱 Nederlands".</returns>
    public static string GetDisplayLabel(string code)
    {
        var iso = Normalize(code);
        foreach (var (metaCode, flag, label, _) in Meta)
        {
            if (metaCode == iso)
            {
                return $"{flag} {label}";
            }
        }

        return $"🌐 {code}";
    }

    /// <summary>
    /// Get the flag emoji for an ISO language code. Falls back to a globe flag for unknown languages.
    /// </summary>
    /// <param name="code">The ISO language code (case-insensitive).</param>
    /// <returns>The flag emoji, e.g. "🇳🇱".</returns>
    public static string GetFlag(string code)
    {
        var iso = Normalize(code);
        foreach (var (metaCode, flag, _, _) in Meta)
        {
            if (metaCode == iso)
            {
                return flag;
            }
        }

        return "🌐";
    }

    /// <summary>
    /// Get the native display label for an ISO language code. Falls back to the raw code for unknown
    /// languages.
    /// </summary>
    /// <param name="code">The ISO language code (case-insensitive).</param>
    /// <returns>The native label, e.g. "Nederlands".</returns>
    public static string GetLabel(string code)
    {
        var iso = Normalize(code);
        foreach (var (metaCode, _, label, _) in Meta)
        {
            if (metaCode == iso)
            {
                return label;
            }
        }

        return code;
    }

    /// <summary>
    /// Match an app/UI/browser locale to one of a feature's available ISO codes, using the
    /// region-variant alternative codes (e.g. "en-GB" -> "en", "de-CH" -> "de"). Matching order:
    /// exact match against an available code, then the alternative-code table, then the base
    /// language code. Returns null when nothing matches, so callers can decide their own fallback.
    /// </summary>
    /// <param name="appLanguage">The app/UI/browser language tag (e.g. "en", "en-US", "nl-BE").</param>
    /// <param name="availableCodes">The codes the feature actually supports.</param>
    /// <returns>The matching available code or null if none matched.</returns>
    public static string? MatchAvailableLanguage(string? appLanguage, System.Collections.Generic.IReadOnlyList<string> availableCodes)
    {
        if (string.IsNullOrEmpty(appLanguage))
        {
            return null;
        }

        var lower = appLanguage.ToLowerInvariant();

        // 1. Exact match against an available code.
        foreach (var code in availableCodes)
        {
            if (string.Equals(code, lower, System.StringComparison.OrdinalIgnoreCase))
            {
                return code;
            }
        }

        // 2. Alternative-code match: find the language whose region variants include this tag, then
        //    return its base code if the feature supports it.
        foreach (var (metaCode, _, _, alternativeCodes) in Meta)
        {
            var isAlternative = false;
            foreach (var alt in alternativeCodes)
            {
                if (string.Equals(alt, lower, System.StringComparison.OrdinalIgnoreCase))
                {
                    isAlternative = true;
                    break;
                }
            }

            if (isAlternative)
            {
                foreach (var code in availableCodes)
                {
                    if (string.Equals(code, metaCode, System.StringComparison.OrdinalIgnoreCase))
                    {
                        return code;
                    }
                }
            }
        }

        // 3. Base language code match (e.g. an unlisted "en-ZZ" still resolves to "en").
        var baseCode = Normalize(appLanguage);
        foreach (var code in availableCodes)
        {
            if (string.Equals(code, baseCode, System.StringComparison.OrdinalIgnoreCase))
            {
                return code;
            }
        }

        return null;
    }

    /// <summary>
    /// Resolve a default language code for an app/UI language, restricted to a set of available
    /// codes. Uses <see cref="MatchAvailableLanguage"/> (region-variant aware), then falls back to
    /// the first available code, otherwise English.
    /// </summary>
    /// <param name="appLanguage">The app/UI language tag.</param>
    /// <param name="availableCodes">The codes the feature actually supports.</param>
    /// <returns>The resolved ISO code.</returns>
    public static string ResolveDefaultLanguage(string? appLanguage, System.Collections.Generic.IReadOnlyList<string> availableCodes)
    {
        return MatchAvailableLanguage(appLanguage, availableCodes)
            ?? (availableCodes.Count > 0 ? availableCodes[0] : DefaultLanguageCode);
    }
}