using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Rendering;
#if UNITY_EDITOR
using UnityEditor;
#endif
using Object = UnityEngine.Object;

namespace UnityEngine.Experimental.Rendering.HDPipeline
{
#if UNITY_EDITOR
    public static class EditorLightUtilities
    {
        public static void DrawSpotlightGizmo(Light spotlight, bool selected)
        {
            var flatRadiusAtRange = spotlight.range * Mathf.Tan(spotlight.spotAngle * Mathf.Deg2Rad * 0.5f);

            var vectorLineUp = Vector3.Normalize(spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * spotlight.range + spotlight.gameObject.transform.up * flatRadiusAtRange - spotlight.gameObject.transform.position);
            var vectorLineDown = Vector3.Normalize(spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * spotlight.range + spotlight.gameObject.transform.up * -flatRadiusAtRange - spotlight.gameObject.transform.position);
            var vectorLineRight = Vector3.Normalize(spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * spotlight.range + spotlight.gameObject.transform.right * flatRadiusAtRange - spotlight.gameObject.transform.position);
            var vectorLineLeft = Vector3.Normalize(spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * spotlight.range + spotlight.gameObject.transform.right * -flatRadiusAtRange - spotlight.gameObject.transform.position);

            var rangeDiscDistance = Mathf.Cos(Mathf.Deg2Rad * spotlight.spotAngle / 2) * spotlight.range;
            var rangeDiscRadius = spotlight.range * Mathf.Sin(spotlight.spotAngle * Mathf.Deg2Rad * 0.5f);
            var nearDiscDistance = Mathf.Cos(Mathf.Deg2Rad * spotlight.spotAngle / 2) * spotlight.shadowNearPlane;
            var nearDiscRadius = spotlight.shadowNearPlane * Mathf.Sin(spotlight.spotAngle * Mathf.Deg2Rad * 0.5f);


            //Draw Range disc
            Handles.Disc(spotlight.gameObject.transform.rotation, spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * rangeDiscDistance, spotlight.gameObject.transform.forward, rangeDiscRadius, false, 1);
            //Draw Lines

            Gizmos.DrawLine(spotlight.gameObject.transform.position, spotlight.gameObject.transform.position + vectorLineUp * spotlight.range);
            Gizmos.DrawLine(spotlight.gameObject.transform.position, spotlight.gameObject.transform.position + vectorLineDown * spotlight.range);
            Gizmos.DrawLine(spotlight.gameObject.transform.position, spotlight.gameObject.transform.position + vectorLineRight * spotlight.range);
            Gizmos.DrawLine(spotlight.gameObject.transform.position, spotlight.gameObject.transform.position + vectorLineLeft * spotlight.range);

            if (selected)
            {
                //Draw Range Arcs
                Handles.DrawWireArc(spotlight.gameObject.transform.position, spotlight.gameObject.transform.right, vectorLineUp, spotlight.spotAngle, spotlight.range);
                Handles.DrawWireArc(spotlight.gameObject.transform.position, spotlight.gameObject.transform.up, vectorLineLeft, spotlight.spotAngle, spotlight.range);
                //Draw Near Plane Disc
                if (spotlight.shadows != LightShadows.None) Handles.Disc(spotlight.gameObject.transform.rotation, spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * nearDiscDistance, spotlight.gameObject.transform.forward, nearDiscRadius, false, 1);

                //Inner Cone
                var additionalLightData = spotlight.GetComponent<HDAdditionalLightData>();
                DrawInnerCone(spotlight,additionalLightData);
            }
        }

        public static void DrawInnerCone(Light spotlight, HDAdditionalLightData additionalLightData)
        {
            if (additionalLightData == null) return;

            var flatRadiusAtRange = spotlight.range * Mathf.Tan(spotlight.spotAngle * additionalLightData.m_InnerSpotPercent * 0.01f * Mathf.Deg2Rad * 0.5f);

            var vectorLineUp = Vector3.Normalize(spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * spotlight.range + spotlight.gameObject.transform.up * flatRadiusAtRange - spotlight.gameObject.transform.position);
            var vectorLineDown = Vector3.Normalize(spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * spotlight.range + spotlight.gameObject.transform.up * -flatRadiusAtRange - spotlight.gameObject.transform.position);
            var vectorLineRight = Vector3.Normalize(spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * spotlight.range + spotlight.gameObject.transform.right * flatRadiusAtRange - spotlight.gameObject.transform.position);
            var vectorLineLeft = Vector3.Normalize(spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * spotlight.range + spotlight.gameObject.transform.right * -flatRadiusAtRange - spotlight.gameObject.transform.position);

            //Draw Lines

            Gizmos.DrawLine(spotlight.gameObject.transform.position, spotlight.gameObject.transform.position + vectorLineUp * spotlight.range);
            Gizmos.DrawLine(spotlight.gameObject.transform.position, spotlight.gameObject.transform.position + vectorLineDown * spotlight.range);
            Gizmos.DrawLine(spotlight.gameObject.transform.position, spotlight.gameObject.transform.position + vectorLineRight * spotlight.range);
            Gizmos.DrawLine(spotlight.gameObject.transform.position, spotlight.gameObject.transform.position + vectorLineLeft * spotlight.range);

            var innerAngle = spotlight.spotAngle * additionalLightData.GetInnerSpotPercent01();
            if (innerAngle > 0)
            {
                var innerDiscDistance = Mathf.Cos(Mathf.Deg2Rad * innerAngle * 0.5f) * spotlight.range;
                var innerDiscRadius = spotlight.range * Mathf.Sin(innerAngle * Mathf.Deg2Rad * 0.5f);
                //Draw Range disc
                Handles.Disc(spotlight.gameObject.transform.rotation, spotlight.gameObject.transform.position + spotlight.gameObject.transform.forward * innerDiscDistance, spotlight.gameObject.transform.forward, innerDiscRadius, false, 1);
            }
        }

        public static void DrawArealightGizmo(Light arealight)
        {

            var RectangleSize = new Vector3(arealight.areaSize.x, arealight.areaSize.y, 0);
            Gizmos.matrix = arealight.transform.localToWorldMatrix;
            Gizmos.DrawWireCube(Vector3.zero, RectangleSize);
            Gizmos.matrix = Matrix4x4.identity;
            Gizmos.DrawWireSphere(arealight.transform.position, arealight.range);
        }

        public static void DrawPointlightGizmo(Light pointlight, bool selected)
        {
            if (pointlight.shadows != LightShadows.None && selected) Gizmos.DrawWireSphere(pointlight.transform.position, pointlight.shadowNearPlane);
            Gizmos.DrawWireSphere(pointlight.transform.position, pointlight.range);
        }

        public static void DrawSpherelightGizmo(Light spherelight)
        {
            var additionalLightData = spherelight.GetComponent<HDAdditionalLightData>();
            if (additionalLightData == null) return;
            Gizmos.DrawSphere(spherelight.transform.position, additionalLightData.shapeLength);
            if (spherelight.shadows != LightShadows.None) Gizmos.DrawWireSphere(spherelight.transform.position, spherelight.shadowNearPlane);
            Gizmos.DrawWireSphere(spherelight.transform.position, spherelight.range);
        }

        public static void DrawFrustumlightGizmo(Light frustumlight)
        {
            var additionalLightData = frustumlight.GetComponent<HDAdditionalLightData>();
            if (additionalLightData == null) return;
            var frustumSize = new Vector3(additionalLightData.shapeLength / frustumlight.gameObject.transform.localScale.x, additionalLightData.shapeWidth / frustumlight.gameObject.transform.localScale.y, frustumlight.range - frustumlight.shadowNearPlane / frustumlight.gameObject.transform.localScale.z);
            Gizmos.matrix = frustumlight.transform.localToWorldMatrix;
            Gizmos.DrawWireCube(Vector3.forward * (frustumSize.z * 0.5f + frustumlight.shadowNearPlane), frustumSize);
            Gizmos.matrix = Matrix4x4.identity;
        }

        public static void DrawDirectionalLightGizmo(Light directionalLight)
        {
            var gizmoSize = 0.2f;
            Handles.Disc(directionalLight.transform.rotation, directionalLight.transform.position, directionalLight.gameObject.transform.forward, gizmoSize, false, 1);
            Gizmos.DrawLine(directionalLight.transform.position, directionalLight.transform.position + directionalLight.transform.forward);
            Gizmos.DrawLine(directionalLight.transform.position + directionalLight.transform.up * gizmoSize, directionalLight.transform.position + directionalLight.transform.up * gizmoSize + directionalLight.transform.forward);
            Gizmos.DrawLine(directionalLight.transform.position + directionalLight.transform.up * -gizmoSize, directionalLight.transform.position + directionalLight.transform.up * -gizmoSize + directionalLight.transform.forward);
            Gizmos.DrawLine(directionalLight.transform.position + directionalLight.transform.right * gizmoSize, directionalLight.transform.position + directionalLight.transform.right * gizmoSize + directionalLight.transform.forward);
            Gizmos.DrawLine(directionalLight.transform.position + directionalLight.transform.right * -gizmoSize, directionalLight.transform.position + directionalLight.transform.right * -gizmoSize + directionalLight.transform.forward);
        }

        public static void DrawCross(Transform m_transform)
        {
            var gizmoSize = 0.25f;
            Gizmos.DrawLine(m_transform.position, m_transform.position + m_transform.TransformVector(m_transform.root.forward * gizmoSize / m_transform.localScale.z));
            Gizmos.DrawLine(m_transform.position, m_transform.position + m_transform.TransformVector(m_transform.root.forward * -gizmoSize / m_transform.localScale.z));
            Gizmos.DrawLine(m_transform.position, m_transform.position + m_transform.TransformVector(m_transform.root.up * gizmoSize / m_transform.localScale.y));
            Gizmos.DrawLine(m_transform.position, m_transform.position + m_transform.TransformVector(m_transform.root.up * -gizmoSize / m_transform.localScale.y));
            Gizmos.DrawLine(m_transform.position, m_transform.position + m_transform.TransformVector(m_transform.root.right * gizmoSize / m_transform.localScale.x));
            Gizmos.DrawLine(m_transform.position, m_transform.position + m_transform.TransformVector(m_transform.root.right * -gizmoSize / m_transform.localScale.x));
        }

        public static bool DrawHeader(string title, bool activeField)
        {
            var backgroundRect = GUILayoutUtility.GetRect(1f, 17f);

            var labelRect = backgroundRect;
            labelRect.xMin += 16f;
            labelRect.xMax -= 20f;

            var toggleRect = backgroundRect;
            toggleRect.y += 2f;
            toggleRect.width = 13f;
            toggleRect.height = 13f;

            var menuIcon = EditorGUIUtility.isProSkin
                ? (Texture2D)EditorGUIUtility.Load("Builtin Skins/DarkSkin/Images/pane options.png")
                : (Texture2D)EditorGUIUtility.Load("Builtin Skins/LightSkin/Images/pane options.png");

            var menuRect = new Rect(labelRect.xMax + 4f, labelRect.y + 4f, menuIcon.width, menuIcon.height);

            // Background rect should be full-width
            backgroundRect.xMin = 0f;
            backgroundRect.width += 4f;

            // Background
            float backgroundTint = EditorGUIUtility.isProSkin ? 0.1f : 1f;
            EditorGUI.DrawRect(backgroundRect, new Color(backgroundTint, backgroundTint, backgroundTint, 0.2f));

            // Title
            using (new EditorGUI.DisabledScope(!activeField))
                EditorGUI.LabelField(labelRect, title, EditorStyles.boldLabel);

            // Active checkbox
            activeField = GUI.Toggle(toggleRect, activeField, GUIContent.none, new GUIStyle("ShurikenCheckMark"));

            var e = Event.current;
            if (e.type == EventType.MouseDown && backgroundRect.Contains(e.mousePosition) && e.button == 0)
            {
                activeField = !activeField;
                e.Use();
            }

            EditorGUILayout.Space();

            return activeField;
        }

        public static void DrawHeader(string title)
        {
            var backgroundRect = GUILayoutUtility.GetRect(1f, 17f);

            var labelRect = backgroundRect;
            labelRect.xMin += 16f;
            labelRect.xMax -= 20f;

            var foldoutRect = backgroundRect;
            foldoutRect.y += 1f;
            foldoutRect.width = 13f;
            foldoutRect.height = 13f;

            // Background rect should be full-width
            backgroundRect.xMin = 0f;
            backgroundRect.width += 4f;

            // Background
            float backgroundTint = EditorGUIUtility.isProSkin ? 0.1f : 1f;
            EditorGUI.DrawRect(backgroundRect, new Color(backgroundTint, backgroundTint, backgroundTint, 0.2f));

            // Title
            EditorGUI.LabelField(labelRect, title, EditorStyles.boldLabel);
            EditorGUILayout.Space();
        }

        public static void DrawSplitter()
        {
            var rect = GUILayoutUtility.GetRect(1f, 1f);

            // Splitter rect should be full-width
            rect.xMin = 0f;
            rect.width += 4f;

            if (Event.current.type != EventType.Repaint)
                return;

            EditorGUI.DrawRect(rect, !EditorGUIUtility.isProSkin
                ? new Color(0.6f, 0.6f, 0.6f, 1.333f)
                : new Color(0.12f, 0.12f, 0.12f, 1.333f));
        }

        public static bool DrawHeaderFoldout(string title, bool state)
        {
            var backgroundRect = GUILayoutUtility.GetRect(1f, 17f);

            var labelRect = backgroundRect;
            labelRect.xMin += 16f;
            labelRect.xMax -= 20f;

            var foldoutRect = backgroundRect;
            foldoutRect.y += 1f;
            foldoutRect.width = 13f;
            foldoutRect.height = 13f;

            // Background rect should be full-width
            backgroundRect.xMin = 0f;
            backgroundRect.width += 4f;

            // Background
            float backgroundTint = EditorGUIUtility.isProSkin ? 0.1f : 1f;
            EditorGUI.DrawRect(backgroundRect, new Color(backgroundTint, backgroundTint, backgroundTint, 0.2f));

            // Title
            EditorGUI.LabelField(labelRect, title, EditorStyles.boldLabel);

            // Active checkbox
            state = GUI.Toggle(foldoutRect, state, GUIContent.none, EditorStyles.foldout);

            var e = Event.current;
            if (e.type == EventType.MouseDown && backgroundRect.Contains(e.mousePosition) && e.button == 0)
            {
                state = !state;
                e.Use();
            }

            return state;
        }
    }
#endif
}