OTG_5/Assets/_Scripts/UI/DialogueUI.cs

using UnityEngine;
using UnityEngine.UI;

public class DialogueUI : MonoBehaviour
{
    public static DialogueUI Instance { get; private set; }

    public GameObject root;
    public Text nameText;
    public Text bodyText;
    public RectTransform responseContainer;
    public Button responseButtonTemplate;

    public bool IsOpen => root != null && root.activeSelf;

    private void Awake()
    {
        if (Instance != null && Instance != this)
        {
            Destroy(gameObject);
            return;
        }

        Instance = this;
        Close();
    }

    public void Open(NPCDialogue npc, DialogueData dialogueData)
    {
        if (root == null || dialogueData == null)
        {
            return;
        }

        root.SetActive(true);
        Cursor.lockState = CursorLockMode.None;
        Cursor.visible = true;

        if (nameText != null)
        {
            nameText.text = dialogueData.npcName;
        }

        if (bodyText != null)
        {
            bodyText.text = dialogueData.greeting;
        }

        ClearResponses();

        foreach (DialogueResponse response in dialogueData.responses)
        {
            Button button = Instantiate(responseButtonTemplate, responseContainer, false);
            button.name = $"Response - {response.text}";
            button.gameObject.SetActive(true);

            Text text = button.GetComponentInChildren<Text>();
            if (text != null)
            {
                text.text = response.text;
            }

            QuestData questToStart = response.questToStart;
            button.onClick.AddListener(() =>
            {
                if (questToStart != null && QuestManager.Instance != null)
                {
                    QuestManager.Instance.StartQuest(questToStart);
                }

                Close();
            });
        }

        LayoutRebuilder.ForceRebuildLayoutImmediate(responseContainer);
    }

    public void Close()
    {
        if (root != null)
        {
            root.SetActive(false);
        }

        ClearResponses();
        Cursor.lockState = CursorLockMode.Locked;
        Cursor.visible = false;
    }

    private void ClearResponses()
    {
        if (responseContainer == null)
        {
            return;
        }

        for (int i = responseContainer.childCount - 1; i >= 0; i--)
        {
            Transform child = responseContainer.GetChild(i);
            if (responseButtonTemplate != null && child == responseButtonTemplate.transform)
            {
                continue;
            }

            Destroy(child.gameObject);
        }
    }
}