Scampz/Assets/Scripts/Dialogue/DialogueManager.cs

using System.Collections;
using System.Collections.Generic;
using System.Linq;
using TMPro;
using UnityEngine;

namespace Scampz.GameJam
{
  public class DialogueManager : MonoBehaviour
  {
    [SerializeField]
    private TextMeshProUGUI dialogueTextGUI;
    public float TextSpeed = 0.1f;

    public Queue<string> sentences;

    private static DialogueManager _instance;

    public static DialogueManager Instance
    {
      get
      {
        if (!_instance)
        {
          _instance = new GameObject().AddComponent<DialogueManager>();
          _instance.name = _instance.GetType().ToString();
          DontDestroyOnLoad(_instance.gameObject);
        }

        return _instance;
      }
    }

    public void Start()
    {
      sentences = new Queue<string>();
    }

    public void StartDialogue(Dialogue dialogue)
    {
      sentences.Clear();
      foreach (var sentence in dialogue.sentences)
        sentences.Enqueue(sentence);

      DisplayNextSentence();
    }

    public void DisplayNextSentence()
    {
      if (!sentences.Any())
        EndDialogue();

      var sentence = sentences.Dequeue();
      StopAllCoroutines();
      StartCoroutine(TypeSentence(sentence));
    }

    private IEnumerator TypeSentence(string sentence)
    {

      dialogueTextGUI.text = string.Empty;
      foreach (var letter in sentence.ToCharArray())
      {
        dialogueTextGUI.text += letter;
        yield return null;
        yield return new WaitForSecondsRealtime(TextSpeed);
      }
    }

    private void EndDialogue()
    {
      // do nothing currently
    }
  }
}