using UnityEngine;
using TMPro;

public class ExtendText : MonoBehaviour
{
    [SerializeField] TextMeshProUGUI m_text;
    [SerializeField] bool isAutoInjectLocalization = true;

    SystemLanguage backupTextLanguage = SystemLanguage.Catalan;
    string backupText;

    public RectTransform rectTransform => transform as RectTransform;
    public TextMeshProUGUI TextComponent => m_text;
    public bool IsAutoInjectLocalization
    {
        get => isAutoInjectLocalization;
        set
        {
            if(isAutoInjectLocalization == value) return;
            
            isAutoInjectLocalization = value;

            if(isAutoInjectLocalization)
            {
                InjectLocalization(m_text.text);
                LocalizationText.OnLanguageChange += HandleLanguageChange;
            }
            else
            {
                LocalizationText.OnLanguageChange -= HandleLanguageChange;
                backupTextLanguage = SystemLanguage.Catalan;
                m_text.text = backupText;
            }
        }
    }

    private void Awake()
    {
        if(m_text is null)
            m_text = GetComponent<TextMeshProUGUI>();
    }

    private void OnEnable()
    {
        if(isAutoInjectLocalization)
        {
            if(backupTextLanguage != LocalizationText.Language)
                InjectLocalization(backupText != null ? backupText : m_text.text);

            LocalizationText.OnLanguageChange += HandleLanguageChange;
        }
    }

    private void OnDisable()
    {
        if(isAutoInjectLocalization)
            LocalizationText.OnLanguageChange -= HandleLanguageChange;
    }

    private void HandleLanguageChange() => InjectLocalization(backupText);

    private void InjectLocalization(string targetText)
    {
#if UNITY_EDITOR // validation check, this is not necessary in build
        if (!LocalizationInjector.IsValidateText(targetText)) return;
#endif
        backupText = targetText;
        backupTextLanguage = LocalizationText.Language;
        m_text.text = LocalizationInjector.InjectLocalization(targetText);
    }

    public void SetText(string text)
    {
        if(isAutoInjectLocalization)
            InjectLocalization(text);
        else
            m_text.text = text;
    }

    private void OnValidate()
    {
        if(m_text is null)
            m_text = GetComponent<TextMeshProUGUI>();
    }
}

public static class LocalizationInjector
{
    public static bool IsValidateText(string targetText)
    {
        int openBracketCount = 0;
        for (int i = 0; i < targetText.Length; ++i)
        {
            if (targetText[i] == '[')
                openBracketCount++;
            else if (targetText[i] == ']')
                openBracketCount--;

            if (openBracketCount < 0) return false;
        }

        return openBracketCount == 0;
    }

    public static string InjectLocalization(string targetText)
    {
        Utility.StringBuilder.Clear();

        for (int i = 0; i < targetText.Length; ++i)
        {
            if (targetText[i] == '[')
            {
                string keyWord = string.Empty;
                for (++i; i < targetText.Length; ++i)
                {
                    if (targetText[i] == ']')
                    {
                        Utility.StringBuilder.Append(LocalizationText.GetText(keyWord));
                        break;
                    }
                    else
                    {
                        keyWord += targetText[i];
                    }
                }
            }
            else
            {
                Utility.StringBuilder.Append(targetText[i]);
            }
        }

        return Utility.StringBuilder.ToString();
    }

    public static string MakeToLocalizationKey(string targetText) => FormatString.StringFormat("[{0}]", targetText);
}