// Copyright 2017 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

using UnityEngine;
using UnityEditor;

/// Custom editor for GvrLaserPointer.
/// Adds buttons that allows user's to set the recommended default values for the different
/// raycast modes.
[CustomEditor(typeof(GvrLaserPointer)), CanEditMultipleObjects]
public class GvrLaserPointerEditor : Editor {
  private SerializedProperty mode;
  private SerializedProperty overridePointerCamera;
  private SerializedProperty maxPointerDistance;
  private SerializedProperty defaultReticleDistance;
  private SerializedProperty rayIntersection;
  private SerializedProperty drawDebugRays;


  public const string RAYCAST_MODE_PROP_NAME = "raycastMode";
  public const string OVERRIDE_POINTER_CAMERA_PROP_NAME = "overridePointerCamera";
  public const string MAX_POINTER_DISTANCE_PROP_NAME = "maxPointerDistance";
  public const string DEFAULT_RETICLE_DISTANCE_PROP_NAME = "defaultReticleDistance";
  public const string RAY_INTERSECTION_PROP_NAME = "overrideCameraRayIntersectionDistance";
  public const string DRAW_DEBUG_RAYS_PROP_NAME = "drawDebugRays";

  void OnEnable() {
    mode = serializedObject.FindProperty(RAYCAST_MODE_PROP_NAME);
    overridePointerCamera = serializedObject.FindProperty(OVERRIDE_POINTER_CAMERA_PROP_NAME);
    maxPointerDistance = serializedObject.FindProperty(MAX_POINTER_DISTANCE_PROP_NAME);
    defaultReticleDistance = serializedObject.FindProperty(DEFAULT_RETICLE_DISTANCE_PROP_NAME);
    rayIntersection = serializedObject.FindProperty(RAY_INTERSECTION_PROP_NAME);
    drawDebugRays = serializedObject.FindProperty(DRAW_DEBUG_RAYS_PROP_NAME);
  }

  public override void OnInspectorGUI() {
    serializedObject.Update();

    // Add clickable script field, as would have been provided by DrawDefaultInspector()
    MonoScript script = MonoScript.FromMonoBehaviour(target as MonoBehaviour);
    EditorGUI.BeginDisabledGroup(true);
    EditorGUILayout.ObjectField("Script", script, typeof(MonoScript), false);
    EditorGUI.EndDisabledGroup();

    Rect defaultsRect = EditorGUILayout.BeginVertical();
    GUI.Box(defaultsRect, /* No label. */ "");

    GUILayout.Space(3.0f);

    EditorGUILayout.BeginHorizontal();

    if (GUILayout.Button("Hybrid")) {
      SetDefaultsForRaycastMode(GvrBasePointer.RaycastMode.Hybrid);
    }

    if (GUILayout.Button("Camera")) {
      SetDefaultsForRaycastMode(GvrBasePointer.RaycastMode.Camera);
    }

    if (GUILayout.Button("Direct")) {
      SetDefaultsForRaycastMode(GvrBasePointer.RaycastMode.Direct);
    }

    EditorGUILayout.EndHorizontal();

    EditorGUILayout.HelpBox("Use the above Raycast Mode buttons to reset the following properties to their recommended values.\n\n" +
      "GvrLaserPointer:\n" +
      "   • " + mode.displayName + "\n" +
      "   • " + rayIntersection.displayName + "\n\n" +
      "GvrLaserVisual:\n" +
      "   • Max Laser Distance\n" +
      "   • Shrink Laser\n", MessageType.Info);

    EditorGUILayout.EndVertical();
    EditorGUILayout.Space();

    EditorGUILayout.PropertyField(maxPointerDistance);
    EditorGUILayout.PropertyField(defaultReticleDistance);

    EditorGUILayout.Space();

    EditorGUILayout.LabelField("Advanced:", EditorStyles.boldLabel);
    EditorGUILayout.PropertyField(mode);
    EditorGUILayout.PropertyField(overridePointerCamera);
    EditorGUILayout.PropertyField(rayIntersection);
    EditorGUILayout.PropertyField(drawDebugRays);

    serializedObject.ApplyModifiedProperties();
  }

  private void SetDefaultsForRaycastMode(GvrBasePointer.RaycastMode raycastMode) {
    switch (raycastMode) {
      case GvrBasePointer.RaycastMode.Hybrid:
        mode.intValue = (int)raycastMode;
        rayIntersection.floatValue = GvrVRHelpers.GetRayIntersection(raycastMode);
        SetPropertiesForVisual(GvrVRHelpers.GetShrinkLaser(raycastMode), GvrVRHelpers.GetRecommendedMaxLaserDistance(raycastMode));
        break;
      case GvrBasePointer.RaycastMode.Camera:
        mode.intValue = (int)raycastMode;
        rayIntersection.floatValue = GvrVRHelpers.GetRayIntersection(raycastMode);
        SetPropertiesForVisual(GvrVRHelpers.GetShrinkLaser(raycastMode), GvrVRHelpers.GetRecommendedMaxLaserDistance(raycastMode));
        break;
      case GvrBasePointer.RaycastMode.Direct:
        mode.intValue = (int)raycastMode;
        rayIntersection.floatValue = GvrVRHelpers.GetRayIntersection(raycastMode);
        SetPropertiesForVisual(GvrVRHelpers.GetShrinkLaser(raycastMode), GvrVRHelpers.GetRecommendedMaxLaserDistance(raycastMode));
        break;
      default:
        Debug.LogError("Trying to set defaults for invalid Raycast Mode: " + raycastMode);
        return;
    }
  }

  private void SetPropertiesForVisual(bool shrinkLaser, float maxLaserDistance) {
    foreach (Object obj in serializedObject.targetObjects) {
      GvrLaserVisual laserVisual = (obj as MonoBehaviour).GetComponent<GvrLaserVisual>();
      if (laserVisual != null) {
        SerializedObject serializedLaserVisual = new SerializedObject(laserVisual);

        SerializedProperty serializedShrinkLaser =
          serializedLaserVisual.FindProperty(GvrLaserVisualEditor.SHRINK_LASER_PROP_NAME);
        serializedShrinkLaser.boolValue = shrinkLaser;

        SerializedProperty serializedMaxLaserDistance =
          serializedLaserVisual.FindProperty(GvrLaserVisualEditor.MAX_LASER_DISTANCE_PROP_NAME);
        serializedMaxLaserDistance.floatValue = maxLaserDistance;

        serializedLaserVisual.ApplyModifiedProperties();
      }
    }
  }
}