using System.Collections.Generic;
using Game.NavigationTool.Editor.Toolbar;
using JetBrains.Annotations;
using UnityEditor;
using UnityEditorInternal;
using UnityEngine;
using UTools = UnityEditor.Tools;

namespace Game.NavigationTool.Editor.Tools
{
    [UsedImplicitly]
    internal sealed class ToolUICanvasPicker : IToolbarDrawer
    {
        public bool Visible => true;
        public bool Enabled => !EditorApplication.isPlayingOrWillChangePlaymode;
        public EToolbarPlacement Placement => EToolbarPlacement.Left;

        private static bool IS_DIRTY = true;
        private static string[] OPTIONS = new string[0];
        private static int[] INSTANCE_IDS = new int[0];

        private void Initialize()
        {
            if (!IS_DIRTY)
                return;

            Canvas[] canvases = Object.FindObjectsOfType<Canvas>();
            var list = new List<Canvas>(canvases.Length);
            var listNames = new List<string>(canvases.Length);
            var listIds = new List<int>(canvases.Length);
            
            listNames.Add("Select");
            listIds.Add(-1);

            for (var i = 0; i < canvases.Length; i++)
            {
                Canvas root = canvases[i].rootCanvas;
                
                if (list.Contains(root))
                    continue;
                
                list.Add(root);
                listNames.Add(root.name);
                listIds.Add(root.GetInstanceID());
            }

            OPTIONS = listNames.ToArray();
            INSTANCE_IDS = listIds.ToArray();
            IS_DIRTY = false;
        }

        public void Update()
        {
            Initialize();
        }

        public void Draw(Rect rect, Styles styles)
        {
            Initialize();
            int temp = EditorGUI.Popup(rect, 0, OPTIONS, styles.popup);

            if (temp != 0 && OPTIONS.Length != 1)
                Focus(INSTANCE_IDS[temp]);
        }

        public float CalculateWidth()
        {
            return 100.0f;
        }

        private static void Focus(int instanceId)
        {
            var canvas = EditorUtility.InstanceIDToObject(instanceId) as Canvas;

            if (canvas == null)
                return;

            Selection.activeObject = canvas;
            Bounds bounds = InternalEditorUtility.CalculateSelectionBounds(false, true, true);
            Vector3 point = bounds.center;
            Quaternion direction = canvas.transform.rotation;
            float size = Mathf.Max(bounds.extents.x, bounds.extents.y);
            bool ortho = canvas.renderMode == RenderMode.ScreenSpaceOverlay;

            for (var i = 0; i < SceneView.sceneViews.Count; i++)
            {
                var view = (SceneView)SceneView.sceneViews[i];
                view.in2DMode = false;
                view.LookAt(point, direction, size, ortho, false);
            }
        }

        public static void SetAsDirty()
        {
            IS_DIRTY = true;
        }
    }
}