#define NAVMESHCOMPONENTS_SHOW_NAVMESHDATA_REF

using System;
using UnityEditor;
using UnityEditor.AI;
#if !UNITY_2021_2_OR_NEWER
using UnityEditor.Experimental.SceneManagement;
#endif
using UnityEditor.SceneManagement;
using UnityEditor.IMGUI.Controls;
using UnityEditorInternal;
using UnityEngine.AI;
using UnityEngine;
using System.Linq;

namespace Unity.AI.Navigation.Editor
{
    [CanEditMultipleObjects]
    [CustomEditor(typeof(NavMeshSurface))]
    class NavMeshSurfaceEditor : UnityEditor.Editor
    {
        SerializedProperty m_AgentTypeID;
        SerializedProperty m_BuildHeightMesh;
        SerializedProperty m_Center;
        SerializedProperty m_CollectObjects;
        SerializedProperty m_DefaultArea;
#if UNITY_2022_2_OR_NEWER
        SerializedProperty m_GenerateLinks;
#endif
        SerializedProperty m_LayerMask;
        SerializedProperty m_OverrideTileSize;
        SerializedProperty m_OverrideVoxelSize;
        SerializedProperty m_Size;
        SerializedProperty m_TileSize;
        SerializedProperty m_UseGeometry;
        SerializedProperty m_VoxelSize;
        SerializedProperty m_MinRegionArea;
        SerializedProperty m_LedgeDropHeight;
        SerializedProperty m_MaxJumpAcrossDistance;

#if NAVMESHCOMPONENTS_SHOW_NAVMESHDATA_REF
        SerializedProperty m_NavMeshData;
#endif
        
        class Styles
        {
            internal readonly GUIContent m_LayerMask = new GUIContent("Include Layers");
            internal readonly GUIContent m_MinRegionArea = new GUIContent("Minimum Region Area");
            internal readonly GUIContent m_GenerateLinks = new GUIContent(
                "Generate Links",
                "If enabled, collected objects will generate links depending on the agent settings values for drop height and jump distance.\nThis behaviour can be overriden using NavMeshModifier components.");
        }

        static Styles s_Styles;

        static bool s_ShowDebugOptions;

        static Color s_HandleColor = new Color(127f, 214f, 244f, 100f) / 255;
        static Color s_HandleColorSelected = new Color(127f, 214f, 244f, 210f) / 255;
        static Color s_HandleColorDisabled = new Color(127f * 0.75f, 214f * 0.75f, 244f * 0.75f, 100f) / 255;

        BoxBoundsHandle m_BoundsHandle = new BoxBoundsHandle();

        bool editingCollider
        {
            get { return EditMode.editMode == EditMode.SceneViewEditMode.Collider && EditMode.IsOwner(this); }
        }

        void OnEnable()
        {
            m_AgentTypeID = serializedObject.FindProperty("m_AgentTypeID");
            m_BuildHeightMesh = serializedObject.FindProperty("m_BuildHeightMesh");
            m_Center = serializedObject.FindProperty("m_Center");
            m_CollectObjects = serializedObject.FindProperty("m_CollectObjects");
            m_DefaultArea = serializedObject.FindProperty("m_DefaultArea");
#if UNITY_2022_2_OR_NEWER
            m_GenerateLinks = serializedObject.FindProperty("m_GenerateLinks");
#endif
            m_LayerMask = serializedObject.FindProperty("m_LayerMask");
            m_OverrideTileSize = serializedObject.FindProperty("m_OverrideTileSize");
            m_OverrideVoxelSize = serializedObject.FindProperty("m_OverrideVoxelSize");
            m_Size = serializedObject.FindProperty("m_Size");
            m_TileSize = serializedObject.FindProperty("m_TileSize");
            m_UseGeometry = serializedObject.FindProperty("m_UseGeometry");
            m_VoxelSize = serializedObject.FindProperty("m_VoxelSize");
            m_MinRegionArea = serializedObject.FindProperty("m_MinRegionArea");

#if NAVMESHCOMPONENTS_SHOW_NAVMESHDATA_REF
            m_NavMeshData = serializedObject.FindProperty("m_NavMeshData");
#endif

#if !UNITY_2022_2_OR_NEWER
            NavMeshVisualizationSettings.showNavigation++;
#endif
        }

#if !UNITY_2022_2_OR_NEWER
        void OnDisable()
        {
            NavMeshVisualizationSettings.showNavigation--;
        }
#endif

        Bounds GetBounds()
        {
            var navSurface = (NavMeshSurface)target;
            return new Bounds(navSurface.transform.position, navSurface.size);
        }

        public override void OnInspectorGUI()
        {
            if (s_Styles == null)
                s_Styles = new Styles();

            serializedObject.Update();

            var bs = NavMesh.GetSettingsByID(m_AgentTypeID.intValue);

            if (bs.agentTypeID != -1)
            {
                // Draw image
                const float diagramHeight = 80.0f;
                Rect agentDiagramRect = EditorGUILayout.GetControlRect(false, diagramHeight);
                NavMeshEditorHelpers.DrawAgentDiagram(agentDiagramRect, bs.agentRadius, bs.agentHeight, bs.agentClimb, bs.agentSlope);
            }
            NavMeshComponentsGUIUtility.AgentTypePopup("Agent Type", m_AgentTypeID);

            NavMeshComponentsGUIUtility.AreaPopup("Default Area", m_DefaultArea);
#if UNITY_2022_2_OR_NEWER
            EditorGUILayout.PropertyField(m_GenerateLinks, s_Styles.m_GenerateLinks);
#endif
            
            EditorGUILayout.PropertyField(m_UseGeometry);

            m_CollectObjects.isExpanded = EditorGUILayout.Foldout(m_CollectObjects.isExpanded, "Object Collection");

            if (m_CollectObjects.isExpanded)
            {
                EditorGUI.indentLevel++;
                
                EditorGUILayout.PropertyField(m_CollectObjects);
                if ((CollectObjects)m_CollectObjects.enumValueIndex == CollectObjects.Volume)
                {
                    EditorGUI.indentLevel++;

                    EditMode.DoEditModeInspectorModeButton(EditMode.SceneViewEditMode.Collider, "Edit Volume",
                        EditorGUIUtility.IconContent("EditCollider"), GetBounds, this);
                    EditorGUILayout.PropertyField(m_Size);
                    EditorGUILayout.PropertyField(m_Center);

                    EditorGUI.indentLevel--;
                }
                else
                {
                    if (editingCollider)
                        EditMode.QuitEditMode();
                }

                EditorGUILayout.PropertyField(m_LayerMask, s_Styles.m_LayerMask);
                
                EditorGUI.indentLevel--;
            }

            EditorGUILayout.Space();

            m_OverrideVoxelSize.isExpanded = EditorGUILayout.Foldout(m_OverrideVoxelSize.isExpanded, "Advanced");
            if (m_OverrideVoxelSize.isExpanded)
            {
                EditorGUI.indentLevel++;

                // Override voxel size.
                EditorGUILayout.PropertyField(m_OverrideVoxelSize);

                using (new EditorGUI.DisabledScope(!m_OverrideVoxelSize.boolValue || m_OverrideVoxelSize.hasMultipleDifferentValues))
                {
                    EditorGUI.indentLevel++;

                    EditorGUILayout.PropertyField(m_VoxelSize);

                    if (!m_OverrideVoxelSize.hasMultipleDifferentValues)
                    {
                        if (!m_AgentTypeID.hasMultipleDifferentValues)
                        {
                            float voxelsPerRadius = m_VoxelSize.floatValue > 0.0f ? (bs.agentRadius / m_VoxelSize.floatValue) : 0.0f;
                            EditorGUILayout.LabelField(" ", voxelsPerRadius.ToString("0.00") + " voxels per agent radius", EditorStyles.miniLabel);
                        }
                        if (m_OverrideVoxelSize.boolValue)
                            EditorGUILayout.HelpBox("Voxel size controls how accurately the navigation mesh is generated from the level geometry. A good voxel size is 2-4 voxels per agent radius. Making voxel size smaller will increase build time.", MessageType.None);
                    }
                    EditorGUI.indentLevel--;
                }

                // Override tile size
                EditorGUILayout.PropertyField(m_OverrideTileSize);

                using (new EditorGUI.DisabledScope(!m_OverrideTileSize.boolValue || m_OverrideTileSize.hasMultipleDifferentValues))
                {
                    EditorGUI.indentLevel++;

                    EditorGUILayout.PropertyField(m_TileSize);

                    if (!m_TileSize.hasMultipleDifferentValues && !m_VoxelSize.hasMultipleDifferentValues)
                    {
                        float tileWorldSize = m_TileSize.intValue * m_VoxelSize.floatValue;
                        EditorGUILayout.LabelField(" ", tileWorldSize.ToString("0.00") + " world units", EditorStyles.miniLabel);
                    }

                    if (!m_OverrideTileSize.hasMultipleDifferentValues)
                    {
                        if (m_OverrideTileSize.boolValue)
                            EditorGUILayout.HelpBox("Tile size controls the how local the changes to the world are (rebuild or carve). Small tile size allows more local changes, while potentially generating more data overall.", MessageType.None);
                    }
                    EditorGUI.indentLevel--;
                }

                EditorGUILayout.PropertyField(m_MinRegionArea, s_Styles.m_MinRegionArea);

                // Height mesh
#if UNITY_2022_2_OR_NEWER
                var heightMeshGUIContent = new GUIContent(m_BuildHeightMesh.displayName, "Generate an accurate height mesh for precise agent placement (slower).");
                EditorGUILayout.PropertyField(m_BuildHeightMesh, heightMeshGUIContent);
#else
                using (new EditorGUI.DisabledScope(true))
                {
                    var heightMeshGUIContent = new GUIContent(m_BuildHeightMesh.displayName, "HeightMesh functionality is only available with Unity 2022.2 or newer.");
                    EditorGUILayout.PropertyField(m_BuildHeightMesh, heightMeshGUIContent);
                }
#endif

                EditorGUILayout.Space();
                EditorGUI.indentLevel--;
            }

            EditorGUILayout.Space();

            serializedObject.ApplyModifiedProperties();

            var hadError = false;
            var multipleTargets = targets.Length > 1;
            foreach (NavMeshSurface navSurface in targets)
            {
                var settings = navSurface.GetBuildSettings();
                // Calculating bounds is potentially expensive when unbounded - so here we just use the center/size.
                // It means the validation is not checking vertical voxel limit correctly when the surface is set to something else than "in volume".
                var bounds = new Bounds(Vector3.zero, Vector3.zero);
                if (navSurface.collectObjects == CollectObjects.Volume)
                {
                    bounds = new Bounds(navSurface.center, navSurface.size);
                }

                var errors = settings.ValidationReport(bounds);
                if (errors.Length > 0)
                {
                    if (multipleTargets)
                        EditorGUILayout.LabelField(navSurface.name);
                    foreach (var err in errors)
                    {
                        EditorGUILayout.HelpBox(err, MessageType.Warning);
                    }
                    GUILayout.BeginHorizontal();
                    GUILayout.Space(EditorGUIUtility.labelWidth);
                    if (GUILayout.Button("Open Agent Settings...", EditorStyles.miniButton))
                        NavMeshEditorHelpers.OpenAgentSettings(navSurface.agentTypeID);
                    GUILayout.EndHorizontal();
                    hadError = true;
                }
            }

            if (hadError)
                EditorGUILayout.Space();

#if NAVMESHCOMPONENTS_SHOW_NAVMESHDATA_REF
            var nmdRect = EditorGUILayout.GetControlRect(true, EditorGUIUtility.singleLineHeight);

            EditorGUI.BeginProperty(nmdRect, GUIContent.none, m_NavMeshData);
            var rectLabel = EditorGUI.PrefixLabel(nmdRect, GUIUtility.GetControlID(FocusType.Passive), new GUIContent(m_NavMeshData.displayName));
            EditorGUI.EndProperty();

            using (new EditorGUI.DisabledScope(true))
            {
                EditorGUI.BeginProperty(nmdRect, GUIContent.none, m_NavMeshData);
                EditorGUI.ObjectField(rectLabel, m_NavMeshData, GUIContent.none);
                EditorGUI.EndProperty();
            }
#endif
            using (new EditorGUI.DisabledScope(Application.isPlaying || m_AgentTypeID.intValue == -1))
            {
                GUILayout.BeginHorizontal();
                GUILayout.Space(EditorGUIUtility.labelWidth);

                using (new EditorGUI.DisabledScope(targets.All(s => (s as NavMeshSurface)?.navMeshData == null)))
                {
                    if (GUILayout.Button("Clear"))
                    {
                        NavMeshAssetManager.instance.ClearSurfaces(targets);
                        SceneView.RepaintAll();
                    }    
                }

                if (GUILayout.Button("Bake"))
                {
                    NavMeshAssetManager.instance.StartBakingSurfaces(targets);
                }

                GUILayout.EndHorizontal();
                
                // Inform when selected target is being baked
                var bakeOperations = NavMeshAssetManager.instance.GetBakeOperations();
                bool bakeInProgress = bakeOperations.Any(b =>
                {
                    if (!targets.Contains(b.surface))
                        return false;

                    return b.bakeOperation != null;
                });
                
                if (bakeInProgress)
                {
                    GUILayout.BeginVertical(EditorStyles.helpBox);
                    
                    if (GUILayout.Button("NavMesh baking is in progress.", EditorStyles.linkLabel))
                        Progress.ShowDetails(false);
                    
                    GUILayout.EndHorizontal();
                }
            }
        }

#if UNITY_2022_2_OR_NEWER
        [DrawGizmo(GizmoType.InSelectionHierarchy | GizmoType.Active | GizmoType.Pickable)]
        static void RenderGizmoSelected(NavMeshSurface navSurface, GizmoType gizmoType)
        {
            navSurface.navMeshDataInstance.FlagAsInSelectionHierarchy();
            DrawBoundingBoxGizmoAndIcon(navSurface, true);
        }

        [DrawGizmo(GizmoType.NotInSelectionHierarchy | GizmoType.Pickable)]
        static void RenderGizmoNotSelected(NavMeshSurface navSurface, GizmoType gizmoType)
        {
            DrawBoundingBoxGizmoAndIcon(navSurface, false);
        }
#else
        [DrawGizmo(GizmoType.Selected | GizmoType.Active | GizmoType.Pickable)]
        static void RenderBoxGizmoSelected(NavMeshSurface navSurface, GizmoType gizmoType)
        {
            DrawBoundingBoxGizmoAndIcon(navSurface, true);
        }

        [DrawGizmo(GizmoType.NotInSelectionHierarchy | GizmoType.Pickable)]
        static void RenderBoxGizmoNotSelected(NavMeshSurface navSurface, GizmoType gizmoType)
        {
            if (NavMeshVisualizationSettings.showNavigation > 0)
                DrawBoundingBoxGizmoAndIcon(navSurface, false);
            else
                Gizmos.DrawIcon(navSurface.transform.position, "NavMeshSurface Icon", true);
        }
#endif

        static void DrawBoundingBoxGizmoAndIcon(NavMeshSurface navSurface, bool selected)
        {
            var color = selected ? s_HandleColorSelected : s_HandleColor;
            if (!navSurface.enabled)
                color = s_HandleColorDisabled;

            var oldColor = Gizmos.color;
            var oldMatrix = Gizmos.matrix;

            // Use the unscaled matrix for the NavMeshSurface
            var localToWorld = Matrix4x4.TRS(navSurface.transform.position, navSurface.transform.rotation, Vector3.one);
            Gizmos.matrix = localToWorld;

            if (navSurface.collectObjects == CollectObjects.Volume)
            {
                Gizmos.color = color;
                Gizmos.DrawWireCube(navSurface.center, navSurface.size);

                if (selected && navSurface.enabled)
                {
                    var colorTrans = new Color(color.r * 0.75f, color.g * 0.75f, color.b * 0.75f, color.a * 0.15f);
                    Gizmos.color = colorTrans;
                    Gizmos.DrawCube(navSurface.center, navSurface.size);
                }
            }
            else
            {
                if (navSurface.navMeshData != null)
                {
                    var bounds = navSurface.navMeshData.sourceBounds;
                    Gizmos.color = Color.grey;
                    Gizmos.DrawWireCube(bounds.center, bounds.size);
                }
            }

            Gizmos.matrix = oldMatrix;
            Gizmos.color = oldColor;

            Gizmos.DrawIcon(navSurface.transform.position, "NavMeshSurface Icon", true);
        }

        void OnSceneGUI()
        {
            if (!editingCollider)
                return;

            var navSurface = (NavMeshSurface)target;
            var color = navSurface.enabled ? s_HandleColor : s_HandleColorDisabled;
            var localToWorld = Matrix4x4.TRS(navSurface.transform.position, navSurface.transform.rotation, Vector3.one);
            using (new Handles.DrawingScope(color, localToWorld))
            {
                m_BoundsHandle.center = navSurface.center;
                m_BoundsHandle.size = navSurface.size;

                EditorGUI.BeginChangeCheck();
                m_BoundsHandle.DrawHandle();
                if (EditorGUI.EndChangeCheck())
                {
                    Undo.RecordObject(navSurface, "Modified NavMesh Surface");
                    Vector3 center = m_BoundsHandle.center;
                    Vector3 size = m_BoundsHandle.size;
                    navSurface.center = center;
                    navSurface.size = size;
                    EditorUtility.SetDirty(target);
                }
            }
        }

        [MenuItem("GameObject/AI/NavMesh Surface", false, 2000)]
        public static void CreateNavMeshSurface(MenuCommand menuCommand)
        {
            var parent = menuCommand.context as GameObject;
            var go = NavMeshComponentsGUIUtility.CreateAndSelectGameObject("NavMesh Surface", parent);
            go.AddComponent<NavMeshSurface>();
            var view = SceneView.lastActiveSceneView;
            if (view != null)
                view.MoveToView(go.transform);
        }
    }
}