using UnityEngine;
using UnityEngine.ProBuilder;
using UnityEngine.ProBuilder.MeshOperations;
using UnityEngine.UIElements;

namespace UnityEditor.ProBuilder.Actions
{
    sealed class ExtrudeFaces : MenuAction
    {
        Pref<float> m_ExtrudeDistance = new Pref<float>("ExtrudeFaces.distance", .5f);

        ExtrudeMethod extrudeMethod
        {
            get { return VertexManipulationTool.s_ExtrudeMethod; }
            set { VertexManipulationTool.s_ExtrudeMethod.value = value; }
        }

        public override ToolbarGroup group
        {
            get { return ToolbarGroup.Geometry; }
        }

        public override string iconPath => "Toolbar/Face_Extrude";
        public override Texture2D icon => IconUtility.GetIcon(iconPath);

        public override TooltipContent tooltip
        {
            get { return s_Tooltip; }
        }

        protected internal override bool hasFileMenuEntry
        {
            get { return false; }
        }

        Texture2D[] m_Icons = null;

        static readonly TooltipContent s_Tooltip = new TooltipContent
            (
                "Extrude Faces",
                "Extrude selected faces, either as a group or individually.\n\nAlt + Click this button to show additional Extrude options.",
                keyCommandSuper, 'E'
            );

        public ExtrudeFaces()
        {
            m_Icons = new Texture2D[3];
            m_Icons[(int)ExtrudeMethod.IndividualFaces] = IconUtility.GetIcon("Toolbar/ExtrudeFace_Individual");
            m_Icons[(int)ExtrudeMethod.VertexNormal] = IconUtility.GetIcon("Toolbar/ExtrudeFace_VertexNormals");
            m_Icons[(int)ExtrudeMethod.FaceNormal] = IconUtility.GetIcon("Toolbar/ExtrudeFace_FaceNormals");
        }

        public override SelectMode validSelectModes
        {
            get { return SelectMode.Face; }
        }

        public override bool enabled
        {
            get { return base.enabled && MeshSelection.selectedFaceCount > 0; }
        }

        protected override MenuActionState optionsMenuState
        {
            get { return MenuActionState.VisibleAndEnabled; }
        }

        public override VisualElement CreateSettingsContent()
        {
            var root = new VisualElement();

            var extrudeMethodLabel = new Label();
            extrudeMethodLabel.tooltip = " You may also choose to Extrude by Face Normal, Vertex Normal, or as Individual Faces.";
            extrudeMethodLabel.style.backgroundImage = m_Icons[(int)extrudeMethod];
            extrudeMethodLabel.style.height = 22;
            extrudeMethodLabel.style.width = 36;

            var extrudeMethodField = new EnumField("Extrude By", extrudeMethod);
            extrudeMethodField.tooltip = " You may also choose to Extrude by Face Normal, Vertex Normal, or as Individual Faces.";
            extrudeMethodField.RegisterCallback<ChangeEvent<System.Enum>>(evt =>
            {
                var newEnumValue = (ExtrudeMethod)evt.newValue;
                if (extrudeMethod != newEnumValue)
                {
                    extrudeMethod = newEnumValue;
                    extrudeMethodLabel.style.backgroundImage = m_Icons[(int)extrudeMethod];
                    ProBuilderSettings.Save();
                    PreviewActionManager.UpdatePreview();
                }
            });
            extrudeMethodField.style.flexGrow = 1;
            var line = new VisualElement();
            line.style.flexDirection = FlexDirection.Row;
            line.Add(extrudeMethodField);
            line.Add(extrudeMethodLabel);
            root.Add(line);

            var distanceField = new FloatField("Distance");
            distanceField.tooltip = "Extrude Amount determines how far a face will be moved along it's normal when extruding. This value can be negative.";
            distanceField.SetValueWithoutNotify(m_ExtrudeDistance.value);
            distanceField.isDelayed = PreviewActionManager.delayedPreview;
            distanceField.RegisterCallback<ChangeEvent<float>>(evt =>
            {
                m_ExtrudeDistance.SetValue(evt.newValue);
                PreviewActionManager.UpdatePreview();
            });
            root.Add(distanceField);

            System.Action onDelayedPreviewChanged = () =>
            {
                distanceField.isDelayed = PreviewActionManager.delayedPreview;
            };
            PreviewActionManager.delayedPreviewChanged += onDelayedPreviewChanged;
            root.RegisterCallback<DetachFromPanelEvent>(evt =>
            {
                PreviewActionManager.delayedPreviewChanged -= onDelayedPreviewChanged;
            });

            return root;
        }

        protected override void OnSettingsGUI()
        {
            GUILayout.Label("Extrude Settings", EditorStyles.boldLabel);

            EditorGUILayout.HelpBox("Extrude Amount determines how far a face will be moved along it's normal when extruding.  This value can be negative.\n\nYou may also choose to Extrude by Face Normal, Vertex Normal, or as Individual Faces.", MessageType.Info);

            GUILayout.BeginHorizontal();
            GUILayout.FlexibleSpace();
            GUILayout.Label(m_Icons[(int)extrudeMethod]);
            GUILayout.FlexibleSpace();
            GUILayout.EndHorizontal();

            EditorGUI.BeginChangeCheck();

            extrudeMethod = (ExtrudeMethod)EditorGUILayout.EnumPopup("Extrude By", extrudeMethod);
            m_ExtrudeDistance.value = EditorGUILayout.FloatField("Distance", m_ExtrudeDistance);

            if (EditorGUI.EndChangeCheck())
                ProBuilderSettings.Save();

            GUILayout.FlexibleSpace();

            if (GUILayout.Button("Extrude Faces"))
                PerformAction();
        }

        protected override ActionResult PerformActionImplementation()
        {
            if (MeshSelection.selectedObjectCount < 1)
                return ActionResult.NoSelection;

            UndoUtility.RecordSelection("Extrude");

            int extrudedFaceCount = 0;

            foreach (ProBuilderMesh mesh in MeshSelection.topInternal)
            {
                mesh.ToMesh();
                mesh.Refresh(RefreshMask.Normals);

                if (mesh.selectedFaceCount < 1)
                    continue;

                extrudedFaceCount += mesh.selectedFaceCount;
                var selectedFaces = mesh.GetSelectedFaces();

                mesh.Extrude(selectedFaces,
                    VertexManipulationTool.s_ExtrudeMethod,
                    m_ExtrudeDistance);

                mesh.SetSelectedFaces(selectedFaces);

                mesh.Rebuild();
                mesh.Optimize();
            }

            ProBuilderEditor.Refresh();

            if (extrudedFaceCount > 0)
                return new ActionResult(ActionResult.Status.Success, "Extrude");

            return new ActionResult(ActionResult.Status.Canceled, "Extrude\nEmpty Selection");
        }
    }
}