using UnityEngine;
using UnityEngine.UI;
using TMPro;
using System.Collections;
using System.Collections.Generic;
using UnityEngine.SceneManagement; // WAJIB ADA untuk pindah scene

public class MateriManager : MonoBehaviour
{
    [Header("UI Panels")]
    public GameObject panelKategori;
    public GameObject panelDetail;

    [Header("Detail References")]
    public Image detailImage;
    public Image detailTitle;
    public TextMeshProUGUI detailDesc;
    public CanvasGroup detailContentGroup;

    private List<MateriItem> materiAktif;
    private int currentIndex = 0;

    void Start()
    {
        StartCoroutine(AnimasiMasukKategori());
    }

    // --- FUNGSI PINDAH SCENE ---
    // Panggil fungsi ini untuk tombol Back di pojok kiri atas
    public void KeMenuBelajar()
    {
        SceneManager.LoadScene("Menu Belajar"); // Pastikan namanya sama persis dengan di Build Settings
    }

    // --- LOGIKA MATERI ---
    public void BukaKategori(DataKategori data)
    {
        if (data == null || data.daftarMateri.Count == 0) return;
        materiAktif = data.daftarMateri;
        currentIndex = 0;
        if (detailTitle != null) detailTitle.sprite = data.gambarJudulKategori;
        UpdateTampilanMateri();
        panelKategori.SetActive(false);
        panelDetail.SetActive(true);
        StartCoroutine(AnimasiPopUpPanel(panelDetail.transform));
    }

    public void UpdateTampilanMateri()
    {
        if (materiAktif == null || materiAktif.Count == 0) return;
        MateriItem item = materiAktif[currentIndex];
        detailImage.sprite = item.gambarIlustrasi;
        detailDesc.text = item.penjelasan;
        StopCoroutine("FadeInContent");
        StartCoroutine(FadeInContent());
    }

    public void SlideNext()
    {
        if (currentIndex >= materiAktif.Count - 1) Kembali();
        else { currentIndex++; UpdateTampilanMateri(); }
    }

    public void SlidePrevious()
    {
        if (currentIndex <= 0) Kembali();
        else { currentIndex--; UpdateTampilanMateri(); }
    }

    public void Kembali()
    {
        panelDetail.SetActive(false);
        panelKategori.SetActive(true);
        StartCoroutine(AnimasiMasukKategori());
    }

    // --- ANIMASI ---
    IEnumerator AnimasiMasukKategori()
    {
        foreach (Transform child in panelKategori.transform) child.localScale = Vector3.zero;
        foreach (Transform child in panelKategori.transform)
        {
            float t = 0;
            while (t < 1)
            {
                t += Time.deltaTime * 5f;
                child.localScale = Vector3.one * Mathf.Lerp(0, 1.1f, t);
                yield return null;
            }
            child.localScale = Vector3.one;
            yield return new WaitForSeconds(0.05f);
        }
    }

    IEnumerator AnimasiPopUpPanel(Transform panel)
    {
        panel.localScale = Vector3.one * 0.7f;
        float t = 0;
        while (t < 1)
        {
            t += Time.deltaTime * 6f;
            panel.localScale = Vector3.one * Mathf.SmoothStep(0.7f, 1f, t);
            yield return null;
        }
        panel.localScale = Vector3.one;
    }

    IEnumerator FadeInContent()
    {
        if (detailContentGroup == null) yield break;
        detailContentGroup.alpha = 0;
        float durasi = 0.4f;
        float waktu = 0;
        while (waktu < durasi)
        {
            waktu += Time.deltaTime;
            detailContentGroup.alpha = waktu / durasi;
            yield return null;
        }
        detailContentGroup.alpha = 1;
    }
}