using TMPro;
using UnityEngine;

public static class TMPInputSimulator
{
    /// <summary>
    /// 模拟输入字符或字符串
    /// </summary>
    public static void InsertText(CustomTMPInputField field, string textToInsert)
    {
        if (field == null) return;

        int pos = field.caretPosition;
        string currentText = field.text;

        // 插入文字
        field.text = currentText.Substring(0, pos) + textToInsert + currentText.Substring(pos);
        field.caretPosition = pos + textToInsert.Length;

        // 刷新显示
        field.ForceLabelUpdate();
        field.ForceRefresh();

        // 触发 onValueChanged
        field.onValueChanged?.Invoke(field.text);
    }

    /// <summary>
    /// 模拟删除光标前的字符（Backspace）
    /// </summary>
    public static void Backspace(CustomTMPInputField field)
    {
        if (field == null) return;
        int pos = field.caretPosition;

        if (pos <= 0) return;

        string currentText = field.text;
        field.text = currentText.Substring(0, pos - 1) + currentText.Substring(pos);
        field.caretPosition = pos - 1;

        field.ForceLabelUpdate();
        field.ForceRefresh();
        field.onValueChanged?.Invoke(field.text);
    }

    /// <summary>
    /// 模拟删除光标后的字符（Delete）
    /// </summary>
    public static void Delete(CustomTMPInputField field)
    {
        if (field == null) return;
        int pos = field.caretPosition;
        string currentText = field.text;

        if (pos >= currentText.Length) return;

        field.text = currentText.Substring(0, pos) + currentText.Substring(pos + 1);
        field.caretPosition = pos;

        field.ForceLabelUpdate();
        field.ForceRefresh();
        field.onValueChanged?.Invoke(field.text);
    }

    /// <summary>
    /// 移动光标到指定位置
    /// </summary>
    public static void SetCaretPosition(CustomTMPInputField field, int position)
    {
        if (field == null) return;
        field.caretPosition = Mathf.Clamp(position, 0, field.text.Length);
    }

    /// <summary>
    /// 移动光标到文本末尾
    /// </summary>
    public static void MoveCaretToEnd(CustomTMPInputField field)
    {
        if (field == null) return;
        field.caretPosition = field.text.Length;
    }
}