using Misaki.ShaderGUI;
using System.Linq;
using UnityEditor;
using UnityEditor.Rendering;
using UnityEngine;

using static Misaki.HdrpToon.UtsShaderPropertyName.SurfaceInputs;

namespace Misaki.HdrpToon.Editor
{
    public class SurfaceInputsScope : MaterialUIScope<ShaderGUIExpandable>
    {
        private static class Properties
        {
            public static MaterialProperty NormalMap;
            public static MaterialProperty NormalMapScale;

            public static MaterialProperty MaskMap;
            public static MaterialProperty Metallic;
            public static MaterialProperty MetallicRemapMin;
            public static MaterialProperty MetallicRemapMax;
            public static MaterialProperty AORemapMin;
            public static MaterialProperty AORemapMax;
            public static MaterialProperty Smoothness;
            public static MaterialProperty SmoothnessRemapMin;
            public static MaterialProperty SmoothnessRemapMax;

            public static MaterialProperty AnisotropyMap;
            public static MaterialProperty Anisotropy;
            public static MaterialProperty KKColor;
            public static MaterialProperty BSDFContribution;

            public static MaterialProperty SpecularColorMap;
            public static MaterialProperty SpecularColor;
            public static MaterialProperty SpecularFeather;
            public static MaterialProperty SpecularStep;

            public static MaterialProperty emissiveColorLDR;
            public static MaterialProperty emissiveColorMap;
            public static MaterialProperty emissiveIntensity;

            public static MaterialProperty albedoAffectEmissive;
            public static MaterialProperty emissiveExposureWeight;
        }

        private static class Styles
        {
            public static readonly GUIContent NormalMapText = new("Normal Map", "A texture that dictates the bumpiness of the material.");
            public static readonly GUIContent MaskMapText = new("Mask Map", "A texture that dictates the physical properties of the material. R channel for metallic, G channel for ambient occlusion, A channel for smoothness");
            public static readonly GUIContent MetallicText = new("Metallic", "Specifies the metallic value of the material.");
            public static readonly GUIContent MetallicRemap = new("Metallic Remap", "Remap the max and min value of metallic");
            public static readonly GUIContent AORemap = new("AO Remap", "Remap the max and min value of ambient occlusion");
            public static readonly GUIContent SmoothnessText = new("Smoothness", "Specifies the smoothness of the material.");
            public static readonly GUIContent SmoothnessRemapText = new("Smoothness Remap", "Remap the max and min value of smoothness");

            public static readonly GUIContent AnisotropyMapText = new("Anisotropy Map", "Specifies the anisotropy map of the material.");

            public static readonly GUIContent KKColorText = new("KK specular Color", "Specifies the color of KK specular.");
            public static readonly GUIContent BSDFContributionText = new("BSDF Contribution", "BSDF smoothness contribution, 1 means KK Hair smoothness will fully contribute bsdf calculation");

            public static readonly GUIContent SpecularColorMapText = new("Specular Color Map", "Specifies the specular color map of the material.");
            public static readonly GUIContent SpecRemap = new("Specular Remap", "Feather and step value of Toon Specular");

            public static readonly GUIContent emissiveColorText = new("Emissive Color", "The color and color map to set for emissive effect.");
            public static readonly GUIContent albedoAffectEmissiveText = new("Albedo Affect Emissive", "Enable to affect emissive color with base color");

            public static readonly GUIContent emissiveIntensityText = new("Emissive Intensity", "Set the intensity of the emissive color,in Nits");
            public static readonly GUIContent emissiveExposureWeightText = new("Exposure Weight", "Controls how the camera exposure influences the perceived intensity of the emissivity. A weight of 0 means that the emissive intensity is calculated ignoring the exposure; increasing this weight progressively increases the influence of exposure on the final emissive value.");
        }

        protected override ShaderGUIExpandable ExpandableBit => ShaderGUIExpandable.SurfaceInputs;
        protected override GUIContent Header => new("Surface Inputs");

        public override void LoadMaterialProperties()
        {
            Properties.NormalMap = FindProperty("_NormalMap");
            Properties.NormalMapScale = FindProperty("_NormalScale");

            Properties.MaskMap = FindProperty("_MaskMap");
            Properties.Metallic = FindProperty("_Metallic");
            Properties.MetallicRemapMin = FindProperty("_MetallicRemapMin");
            Properties.MetallicRemapMax = FindProperty("_MetallicRemapMax");
            Properties.AORemapMin = FindProperty("_AORemapMin");
            Properties.AORemapMax = FindProperty("_AORemapMax");
            Properties.SmoothnessRemapMin = FindProperty("_SmoothnessRemapMin");
            Properties.SmoothnessRemapMax = FindProperty("_SmoothnessRemapMax");
            Properties.Smoothness = FindProperty("_Smoothness");

            Properties.AnisotropyMap = FindProperty("_AnisotropyMap");
            Properties.Anisotropy = FindProperty("_Anisotropy");
            Properties.KKColor = FindProperty("_KKColor");
            Properties.BSDFContribution = FindProperty("_BSDFContribution");

            Properties.SpecularColorMap = FindProperty("_SpecularColorMap");
            Properties.SpecularColor = FindProperty("_SpecularColor");
            Properties.SpecularFeather = FindProperty("_ToonSpecularFeather");
            Properties.SpecularStep = FindProperty("_ToonSpecularStep");

            Properties.emissiveColorLDR = FindProperty(EMISSIVE_COLOR_LDR);
            Properties.emissiveColorMap = FindProperty(EMISSIVE_COLOR_MAP);
            Properties.albedoAffectEmissive = FindProperty(ALBEDO_AFFECT_EMISSIVE);

            Properties.emissiveIntensity = FindProperty(EMISSIVE_INTENSITY);
            Properties.emissiveExposureWeight = FindProperty(EMISSIVE_EXPOSURE_WEIGHT);
        }

        protected override void DrawContent()
        {
            editor.KeywordTexturePropertySingleLine(Styles.NormalMapText, Properties.NormalMap, Properties.NormalMapScale);

            if (materials.All(mat => mat.GetPBRMode() != PBRMode.Off))
            {
                if (editor.KeywordTexturePropertySingleLine(Styles.MaskMapText, Properties.MaskMap))
                {
                    editor.MinMaxShaderProperty(Properties.MetallicRemapMin, Properties.MetallicRemapMax, 0, 1, Styles.MetallicRemap);
                    editor.MinMaxShaderProperty(Properties.AORemapMin, Properties.AORemapMax, 0, 1, Styles.AORemap);
                    editor.MinMaxShaderProperty(Properties.SmoothnessRemapMin, Properties.SmoothnessRemapMax, 0, 1, Styles.SmoothnessRemapText);
                }
                else
                {
                    if (materials.All(mat => mat.GetPBRMode() != PBRMode.KKHair))
                    {
                        editor.ShaderProperty(Properties.Metallic, Styles.MetallicText);
                    }

                    editor.ShaderProperty(Properties.Smoothness, Styles.SmoothnessText);
                }
            }

            if (materials.All(mat => mat.GetPBRMode() == PBRMode.Anisotropy || mat.GetPBRMode() == PBRMode.KKHair))
            {
                EditorGUILayout.Space();
                editor.KeywordTexturePropertySingleLine(Styles.AnisotropyMapText, Properties.AnisotropyMap, Properties.Anisotropy);
                if (materials.All(mat => mat.GetPBRMode() == PBRMode.KKHair))
                {
                    editor.ShaderProperty(Properties.KKColor, Styles.KKColorText);
                    editor.ShaderProperty(Properties.BSDFContribution, Styles.BSDFContributionText);
                }

                EditorGUILayout.Space();
                EditorGUILayout.LabelField("Anisotropy Map only ST");
                editor.TextureScaleOffsetProperty(Properties.AnisotropyMap);
            }
            else if (materials.All(mat => mat.GetPBRMode() == PBRMode.Toon))
            {
                EditorGUILayout.Space();
                editor.KeywordTexturePropertySingleLine(Styles.SpecularColorMapText, Properties.SpecularColorMap, Properties.SpecularColor);
                editor.MinMaxShaderProperty(Properties.SpecularFeather, Properties.SpecularStep, 0, 1, Styles.SpecRemap);
            }

            EditorGUILayout.Space();
            using (var EmissiveIntentLevel = new EditorGUI.IndentLevelScope(-1))
            {
                EditorGUILayout.LabelField("Emissive", EditorStyles.boldLabel);
            }

            EditorGUI.BeginChangeCheck();
            editor.KeywordTexturePropertySingleLine(Styles.emissiveColorText, Properties.emissiveColorMap, Properties.emissiveColorLDR, "_EMISSIVE_COLOR_MAP");
            editor.ShaderProperty(Properties.emissiveIntensity, Styles.emissiveIntensityText);
            if (EditorGUI.EndChangeCheck())
            {
                foreach (var material in materials)
                {
                    if (material.HasProperty(EMISSIVE_COLOR_LDR) && material.HasProperty(EMISSIVE_INTENSITY) && material.HasProperty(EMISSIVE_COLOR))
                    {
                        // Important: The color picker for kEmissiveColorLDR is LDR and in sRGB color space but Unity don't perform any color space conversion in the color
                        // picker BUT only when sending the color data to the shader... So as we are doing our own calculation here in C#, we must do the conversion ourselves.
                        var emissiveColorLDR = material.GetColor(EMISSIVE_COLOR_LDR);
                        var emissiveColorLDRLinear = new Color(Mathf.GammaToLinearSpace(emissiveColorLDR.r), Mathf.GammaToLinearSpace(emissiveColorLDR.g), Mathf.GammaToLinearSpace(emissiveColorLDR.b));
                        material.SetColor(EMISSIVE_COLOR, emissiveColorLDRLinear * material.GetFloat(EMISSIVE_INTENSITY));
                    }
                }
            }

            EditorGUILayout.Space();
            editor.ShaderProperty(Properties.albedoAffectEmissive, Styles.albedoAffectEmissiveText);
            editor.ShaderProperty(Properties.emissiveExposureWeight, Styles.emissiveExposureWeightText);
        }
    }
}