using System.Linq;
using UnityEngine.ProBuilder;
using UnityEngine;
using UnityEngine.ProBuilder.MeshOperations;

#if UNITY_2020_2_OR_NEWER
using EditorToolManager = UnityEditor.EditorTools.EditorToolManager;
using ToolManager = UnityEditor.EditorTools.ToolManager;
#else
using EditorToolManager = UnityEditor.EditorTools.EditorToolContext;
using ToolManager = UnityEditor.EditorTools.EditorTools;
#endif

namespace UnityEditor.ProBuilder.Actions
{
    sealed class NewPolyShapeToggle : MenuToolToggle
    {
        public override ToolbarGroup group { get { return ToolbarGroup.Tool; } }
        public override Texture2D icon { get { return IconUtility.GetIcon("Toolbar/NewPolyShape", IconSkin.Pro); } }
        public override TooltipContent tooltip { get { return _tooltip; } }
        public override string menuTitle { get { return "New Poly Shape"; } }
        public override int toolbarPriority { get { return 1; } }

        static readonly TooltipContent _tooltip = new TooltipContent
            (
                "New Polygon Shape",
                "Creates a new shape by clicking around a perimeter and extruding."
            );

        public override bool hidden
        {
            get { return false; }
        }

        public override bool enabled
        {
            get { return ProBuilderEditor.instance != null; }
        }

        static bool CanCreateNewPolyShape()
        {
            //If inspector is locked we cannot create new PolyShape.
            //First created inspector seems to hold a specific semantic where
            //if not unlocked no matter how many inspectors are present they will
            //not allow the creation of new PolyShape.
            var inspWindows = InspectorWindow.GetInspectors();

            if (inspWindows.Any(x => x.isLocked))
            {
                if (UnityEditor.EditorUtility.DisplayDialog(
                                    L10n.Tr("Inspector Locked"),
                                    L10n.Tr("To create new Poly Shape you need access to all Inspectors, which are currently locked. Do you wish to unlock all Inpsectors?"),
                                    L10n.Tr("Unlock"),
                                    L10n.Tr("Cancel")))
                {
                    foreach (var insp in inspWindows)
                        insp.isLocked = false;
                }
                else
                {
                    return false;
                }
            }

            return true;
        }

        protected override ActionResult PerformActionImplementation()
        {
            if (!CanCreateNewPolyShape())
                return new ActionResult(ActionResult.Status.Canceled, "Canceled Create Poly Shape");

            GameObject go = new GameObject("PolyShape");
            UndoUtility.RegisterCreatedObjectUndo(go, "Create Poly Shape");
            PolyShape poly = Undo.AddComponent<PolyShape>(go);
            ProBuilderMesh pb = Undo.AddComponent<ProBuilderMesh>(go);
            pb.CreateShapeFromPolygon(poly.m_Points, poly.extrude, poly.flipNormals);
            EditorUtility.InitObject(pb);

             // Special case - we don't want to reset the grid pivot because we rely on it to set the active plane for
             // interaction, regardless of whether snapping is enabled or not.
             if (ProGridsInterface.SnapEnabled() || ProGridsInterface.GridVisible())
             {
                 Vector3 pivot;
                 if (ProGridsInterface.GetPivot(out pivot))
                     go.transform.position = pivot;
             }
             poly.polyEditMode = PolyShape.PolyEditMode.Path;

             ProBuilderEditor.selectMode = SelectMode.Object;

             m_Tool = EditorToolManager.GetSingleton<PolyShapeTool>();
             ( (PolyShapeTool) m_Tool ).UpdateTarget(poly);
             ToolManager.SetActiveTool(m_Tool);

            MenuAction.onPerformAction += ActionPerformed;
            ToolManager.activeToolChanged += OnActiveToolChanged;
            ProBuilderEditor.selectModeChanged += OnSelectModeChanged;

            MeshSelection.objectSelectionChanged += OnObjectSelectionChanged;

            return new ActionResult(ActionResult.Status.Success,"Create Poly Shape");
        }

        void Clear()
        {
            m_Tool = null;
            MenuAction.onPerformAction -= ActionPerformed;
            ToolManager.activeToolChanged -= OnActiveToolChanged;
            ProBuilderEditor.selectModeChanged -= OnSelectModeChanged;
            MeshSelection.objectSelectionChanged -= OnObjectSelectionChanged;

            ProBuilderEditor.Refresh();
        }

        internal override ActionResult EndActivation()
        {
            Clear();
            ToolManager.RestorePreviousTool();
            return new ActionResult(ActionResult.Status.Success,"End Poly Shape");
        }

        ActionResult QuitTool()
        {
            Clear();
            return new ActionResult(ActionResult.Status.Success,"End Poly Shape");
        }

        void ActionPerformed(MenuAction newActionPerformed)
        {
            if(ToolManager.IsActiveTool(m_Tool) && newActionPerformed.GetType() != this.GetType())
                LeaveTool();
        }

        void OnObjectSelectionChanged()
        {
            if( m_Tool == null )
                return;

            if(MeshSelection.activeMesh == null || MeshSelection.activeMesh.GetComponent<PolyShape>() == null)
                EditorApplication.delayCall += () => LeaveTool();
        }

        void OnSelectModeChanged(SelectMode obj)
        {
            LeaveTool();
        }

        void OnActiveToolChanged()
        {
            if(m_Tool != null && ToolManager.activeToolType != m_Tool.GetType())
                 LeaveTool();
        }

        void LeaveTool()
        {
            ActionResult result = QuitTool();
            EditorUtility.ShowNotification(result.notification);
        }
    }
}