using System.Collections;
using HotUpdate.Gameplay;
using TMPro;
using UnityEngine;
using UnityEngine.UI;

namespace HotUpdate.UI
{
    /// <summary>Walks a placeholder explorer over the camp painting and speaks only after a tap.</summary>
    public sealed class HomeExplorerPresenter : MonoBehaviour
    {
        const int Layer = 31;
        static readonly Color Key = new Color(0.07f, 0.02f, 0.09f, 1f);
        static readonly string[] Lines =
        {
            "喷泉今天的水声很好听。",
            "芽芽他们在营地里等你。",
            "想再去弹珠台转转吗？",
            "这条石路是我每天散步的地方。",
            "花开得正好，要不要一起看看？",
            "下一关的路上好像有新朋友。",
            "训练之后，大家都会更有精神。",
            "我在这儿看着营地，你去冒险吧。"
        };

        UiPrefabLoader _loader;
        GameObject _stage;
        Camera _camera;
        Transform _actor;
        RectTransform _button;
        RectTransform _bubble;
        TextMeshProUGUI _line;
        float _hideAt;
        int _last = -1;
        bool _hooked;
        Vector3 _wander;

        public bool Ready => _actor != null;
        public bool Talking => _bubble != null && _bubble.gameObject.activeSelf;
        public string Line => _line != null ? _line.text : "";

        void OnEnable()
        {
            if (_camera != null) _camera.enabled = true;
            else StartCoroutine(Boot());
        }

        void OnDisable()
        {
            if (_camera != null) _camera.enabled = false;
            if (_bubble != null) _bubble.gameObject.SetActive(false);
        }

        void OnDestroy()
        {
            if (_button != null) _button.GetComponent<Button>().onClick.RemoveListener(Speak);
            if (_stage != null) Destroy(_stage);
            if (_camera != null && _camera.targetTexture != null)
            {
                _camera.targetTexture.Release();
                Destroy(_camera.targetTexture);
            }
            _loader?.Dispose();
        }

        IEnumerator Boot()
        {
            var root = transform.parent;
            _button = root.Find("Btn_Explorer") as RectTransform;
            _bubble = root.Find("Panel_ExplorerTalk") as RectTransform;
            _line = root.Find("Panel_ExplorerTalk/Txt_ExplorerTalk").GetComponent<TextMeshProUGUI>();
            _bubble.gameObject.SetActive(false);
            yield return null;

            GameObject prefab = null;
            _loader = new UiPrefabLoader(null, "Assets/Bundles/Characters/Explorer");
            yield return _loader.LoadAsync("ExplorerSimple", loaded => prefab = loaded);
            if (prefab == null || _stage != null) yield break;

            _stage = new GameObject("HomeExplorerStage");
            _stage.transform.position = new Vector3(40f, 0f, 0f);
            _actor = Instantiate(prefab, _stage.transform).transform;
            _actor.localPosition = Vector3.zero;
            _actor.localRotation = Quaternion.Euler(0f, 180f, 0f);
            SetLayer(_actor);

            var lightGo = new GameObject("Light");
            lightGo.transform.SetParent(_stage.transform, false);
            var light = lightGo.AddComponent<Light>();
            light.type = LightType.Directional;
            light.intensity = 1.15f;
            light.cullingMask = 1 << Layer;
            light.transform.rotation = Quaternion.Euler(38f, -28f, 0f);
            SetLayer(lightGo.transform);

            var camGo = new GameObject("Camera");
            camGo.transform.SetParent(_stage.transform, false);
            _camera = camGo.AddComponent<Camera>();
            _camera.clearFlags = CameraClearFlags.SolidColor;
            _camera.backgroundColor = Key;
            _camera.cullingMask = 1 << Layer;
            _camera.orthographic = true;
            _camera.orthographicSize = 1.45f;
            _camera.nearClipPlane = 0.05f;
            _camera.farClipPlane = 30f;
            _camera.allowHDR = false;
            _camera.depth = -50;
            _camera.transform.localPosition = new Vector3(0.15f, 1.7f, -3.6f);
            _camera.transform.LookAt(_stage.transform.TransformPoint(0f, 0.7f, 0f));
            var rt = new RenderTexture(512, 512, 16, RenderTextureFormat.ARGB32);
            rt.Create();
            _camera.targetTexture = rt;

            var raw = gameObject.GetComponent<RawImage>() ?? gameObject.AddComponent<RawImage>();
            raw.texture = rt;
            raw.raycastTarget = false;
            raw.color = Color.white;
            var shader = Shader.Find("AIGame/HomeExplorerCutout");
            if (shader != null)
            {
                var material = new Material(shader);
                material.SetColor("_Key", Key);
                raw.material = material;
            }
            _bubble.gameObject.SetActive(false);
            if (!_hooked && _button != null)
            {
                _button.GetComponent<Button>().onClick.AddListener(Speak);
                _hooked = true;
            }
        }

        void Update()
        {
            if (_actor == null) return;
            float t = Time.time * 0.45f;
            Vector3 next = new Vector3(Mathf.Sin(t) * 1.05f, 0f, Mathf.Sin(t * 0.5f) * 0.28f);
            Vector3 dir = next - _wander;
            _wander = next;
            _actor.localPosition = next;
            if (dir.sqrMagnitude > 0.000001f)
                _actor.localRotation = Quaternion.LookRotation(new Vector3(dir.x, 0f, dir.z)) * Quaternion.Euler(0f, 180f, 0f);
        }

        void LateUpdate()
        {
            if (_actor == null || _camera == null || _button == null) return;
            var stage = (RectTransform)transform;
            Vector3 view = _camera.WorldToViewportPoint(_actor.position + Vector3.up * 0.75f);
            if (view.z < 0f) return;
            Vector3 world = stage.TransformPoint(new Vector3((view.x - 0.5f) * stage.rect.width, (view.y - 0.5f) * stage.rect.height, 0f));
            _button.position = world;
            if (_bubble.gameObject.activeSelf)
            {
                _bubble.position = _button.position + new Vector3(0f, 150f * _button.lossyScale.y, 0f);
                if (Time.unscaledTime >= _hideAt) _bubble.gameObject.SetActive(false);
            }
        }

        public void Speak()
        {
            if (_line == null || _bubble == null) return;
            int index = Random.Range(0, Lines.Length);
            if (Lines.Length > 1 && index == _last) index = (index + 1) % Lines.Length;
            _last = index;
            _line.text = Lines[index];
            _bubble.gameObject.SetActive(true);
            _hideAt = Time.unscaledTime + 3.5f;
        }

        static void SetLayer(Transform root)
        {
            root.gameObject.layer = Layer;
            foreach (Transform child in root) SetLayer(child);
        }
    }
}