using ADOFAIRenderer.Localization;
using HarmonyLib;
using UnityEngine;

namespace ADOFAIRenderer.Patch.Game;

/// <summary>
/// Keeps the mod UI language (<see cref="LocalizationManager"/>) equal to the game language.
/// <para>
/// Patched members: <c>RDString.Setup()</c>, which initializes the game's string table and sets <c>RDString.language</c> from
/// <c>Persistence.language</c> (it returns immediately when already initialized); and <c>RDString.ChangeLanguage(SystemLanguage)</c>,
/// which stores the language in <c>Persistence.language</c>, clears the initialized flag and calls Setup again.
/// </para>
/// <para>Always active (independent of the render stage). Runs on the main Unity thread.</para>
/// </summary>
[HarmonyPatch(typeof(RDString))]
internal static class LanguageSyncPatch
{
    /// <summary>Postfix of <c>RDString.ChangeLanguage</c>: applies the selected language to the mod UI.</summary>
    /// <param name="language">Language passed to ChangeLanguage.</param>
    [HarmonyPatch(nameof(RDString.ChangeLanguage))]
    [HarmonyPostfix]
    public static void OnChangeLanguage(SystemLanguage language)
    {
        LocalizationManager.SetLanguage(language);
    }

    /// <summary>
    /// Postfix of <c>RDString.Setup</c>: applies <c>RDString.language</c> (the language resolved by the game) to the mod UI.
    /// Runs on every Setup call, including the early-return calls made when the string table is already initialized.
    /// </summary>
    [HarmonyPatch(nameof(RDString.Setup))]
    [HarmonyPostfix]
    public static void OnSetup()
    {
        LocalizationManager.SetLanguage(RDString.language);
    }
}