using System;
using UnityEditor;
using UnityEngine;


namespace VRM
{
    public static class BlendShapeClipEditorHelper
    {
        ///
        /// BlendShape List のElement描画
        ///
        public static bool DrawBlendShapeBinding(Rect position, SerializedProperty property,
            PreviewSceneManager scene)
        {
            bool changed = false;
            if (scene != null)
            {
                var height = 16;

                var y = position.y;
                var rect = new Rect(position.x, y, position.width, height);
                int pathIndex;
                var (relChanged, oldIndex) = StringPopup(rect, property.FindPropertyRelative("RelativePath"), scene.SkinnedMeshRendererPathList, out pathIndex);
                if (relChanged)
                {
                    changed = true;
                }

                y += height;
                rect = new Rect(position.x, y, position.width, height);
                if (!relChanged && oldIndex == -1)
                {
                    EditorGUI.HelpBox(rect, "renderer not found ! please fix", MessageType.Error);
                }
                else
                {
                    int blendShapeIndex;
                    if (IntPopup(rect, property.FindPropertyRelative("Index"), scene.GetBlendShapeNames(pathIndex), out blendShapeIndex))
                    {
                        changed = true;
                    }
                }

                y += height;
                rect = new Rect(position.x, y, position.width, height);
                if (FloatSlider(rect, property.FindPropertyRelative("Weight"), 100))
                {
                    changed = true;
                }
            }
            return changed;
        }

        ///
        /// Material List のElement描画
        ///
        public static bool DrawMaterialValueBinding(Rect position, SerializedProperty property,
            PreviewSceneManager scene)
        {
            bool changed = false;
            if (scene != null)
            {
                var height = 16;

                var y = position.y;
                var rect = new Rect(position.x, y, position.width, height);
                int materialIndex;
                if (StringPopup(rect, property.FindPropertyRelative("MaterialName"), scene.MaterialNames, out materialIndex).Item1)
                {
                    changed = true;
                }

                if (materialIndex >= 0)
                {
                    var materialItem = scene.GetMaterialItem(scene.MaterialNames[materialIndex]);
                    if (materialItem != null)
                    {
                        y += height;
                        rect = new Rect(position.x, y, position.width, height);

                        // プロパティ名のポップアップ
                        int propIndex;
                        if (StringPopup(rect, property.FindPropertyRelative("ValueName"), materialItem.PropNames, out propIndex).Item1)
                        {
                            changed = true;
                        }

                        if (propIndex >= 0)
                        {
                            // 有効なプロパティ名が選択された
                            var propItem = materialItem.PropMap[materialItem.PropNames[propIndex]];
                            {
                                switch (propItem.PropertyType)
                                {
                                    case ShaderUtil.ShaderPropertyType.Color:
                                        {
                                            property.FindPropertyRelative("BaseValue").vector4Value = propItem.DefaultValues;

                                            // max
                                            y += height;
                                            rect = new Rect(position.x, y, position.width, height);
                                            if (ColorProp(rect, property.FindPropertyRelative("TargetValue")))
                                            {
                                                changed = true;
                                            }
                                        }
                                        break;

                                    case ShaderUtil.ShaderPropertyType.TexEnv:
                                        {
                                            property.FindPropertyRelative("BaseValue").vector4Value = propItem.DefaultValues;

                                            // max
                                            y += height;
                                            rect = new Rect(position.x, y, position.width, height);
                                            if (OffsetProp(rect, property.FindPropertyRelative("TargetValue")))
                                            {
                                                changed = true;
                                            }
                                        }
                                        break;
                                }
                            }
                        }
                    }
                }
            }
            return changed;
        }

        #region Private
        static (bool, int?) StringPopup(Rect rect, SerializedProperty prop, string[] options, out int newIndex)
        {
            if (options == null)
            {
                newIndex = -1;
                return (false, default);
            }

            var oldIndex = Array.IndexOf(options, prop.stringValue);
            newIndex = EditorGUI.Popup(rect, oldIndex, options);
            if (newIndex != oldIndex && newIndex >= 0 && newIndex < options.Length)
            {
                prop.stringValue = options[newIndex];
                return (true, oldIndex);
            }
            else
            {
                return (false, oldIndex);
            }
        }

        static bool IntPopup(Rect rect, SerializedProperty prop, string[] options, out int newIndex)
        {
            if (options == null)
            {
                newIndex = -1;
                return false;
            }

            var oldIndex = prop.intValue;
            newIndex = EditorGUI.Popup(rect, oldIndex, options);
            if (newIndex != oldIndex && newIndex >= 0 && newIndex < options.Length)
            {
                prop.intValue = newIndex;
                return true;
            }
            else
            {
                return false;
            }
        }

        static bool FloatSlider(Rect rect, SerializedProperty prop, float maxValue)
        {
            var oldValue = prop.floatValue;
            var newValue = EditorGUI.Slider(rect, prop.floatValue, 0, 100f);
            if (newValue != oldValue)
            {
                prop.floatValue = newValue;
                return true;
            }
            else
            {
                return false;
            }
        }

        static bool ColorProp(Rect rect, SerializedProperty prop)
        {
            var oldValue = (Color)prop.vector4Value;
            var newValue = EditorGUI.ColorField(rect, prop.displayName, oldValue);
            if (newValue != oldValue)
            {
                prop.vector4Value = newValue;
                return true;
            }
            else
            {
                return false;
            }
        }

        static Rect AdvanceRect(ref float x, float y, float w, float h)
        {
            var rect = new Rect(x, y, w, h);
            x += w;
            return rect;
        }

        static float[] v2 = new float[2];
        static GUIContent[] l2 = new GUIContent[]{
            new GUIContent("x"),
            new GUIContent("y")
        };
        static Vector4 TilingOffset(Rect rect, string label, Vector4 src)
        {
            /*
            var style = new GUIStyle()
            {
                alignment = TextAnchor.MiddleRight,
            };
            */

            var quad = (rect.width - 56);
            var x = rect.x;
            //EditorGUIUtility.labelWidth = 18;

            EditorGUI.LabelField(AdvanceRect(ref x, rect.y, 40, rect.height), "Tiling");
            v2[0] = src.x;
            v2[1] = src.y;
            EditorGUI.MultiFloatField(AdvanceRect(ref x, rect.y, quad, rect.height), l2, v2);
            src.x = v2[0];
            src.y = v2[1];

            //EditorGUI.LabelField(AdvanceRect(ref x, rect.y, quad, rect.height), "Y", style);
            //src.y = EditorGUI.FloatField(AdvanceRect(ref x, rect.y, quad, rect.height), "Y", src.y);

            rect.y += EditorGUIUtility.singleLineHeight;
            x = rect.x;
            EditorGUI.LabelField(AdvanceRect(ref x, rect.y, 40, rect.height), "Offset");
            v2[0] = src.z;
            v2[1] = src.w;
            EditorGUI.MultiFloatField(AdvanceRect(ref x, rect.y, quad, rect.height), l2, v2);
            src.z = v2[0];
            src.w = v2[1];

            //EditorGUI.LabelField(AdvanceRect(ref x, rect.y, quad * 2, rect.height), "Offset X", style);
            //src.z = EditorGUI.FloatField(AdvanceRect(ref x, rect.y, quad, rect.height), "X", src.z);

            //EditorGUI.LabelField(AdvanceRect(ref x, rect.y, quad, rect.height), "Y", style);
            //src.w = EditorGUI.FloatField(AdvanceRect(ref x, rect.y, quad, rect.height), "Y", src.w);

            return src;
        }

        static bool OffsetProp(Rect rect, SerializedProperty prop)
        {
            var oldValue = prop.vector4Value;
            //var newValue = EditorGUI.Vector4Field(rect, prop.displayName, oldValue);
            var newValue = TilingOffset(rect, prop.displayName, oldValue);
            if (newValue != oldValue)
            {
                prop.vector4Value = newValue;
                return true;
            }
            else
            {
                return false;
            }
        }
        #endregion
    }

    /// https://gist.github.com/gszauer/7799899
    public class TextureScale
    {
        private static Color[] texColors;
        private static Color[] newColors;
        private static int w;
        private static float ratioX;
        private static float ratioY;
        private static int w2;

        public static void Scale(Texture2D tex, int newWidth, int newHeight)
        {
            texColors = tex.GetPixels();
            newColors = new Color[newWidth * newHeight];
            ratioX = 1.0f / ((float)newWidth / (tex.width - 1));
            ratioY = 1.0f / ((float)newHeight / (tex.height - 1));
            w = tex.width;
            w2 = newWidth;

            BilinearScale(0, newHeight);

            tex.Reinitialize(newWidth, newHeight);
            tex.SetPixels(newColors);
            tex.Apply();
        }

        private static void BilinearScale(int start, int end)
        {
            for (var y = start; y < end; y++)
            {
                int yFloor = (int)Mathf.Floor(y * ratioY);
                var y1 = yFloor * w;
                var y2 = (yFloor + 1) * w;
                var yw = y * w2;

                for (var x = 0; x < w2; x++)
                {
                    int xFloor = (int)Mathf.Floor(x * ratioX);
                    var xLerp = x * ratioX - xFloor;
                    newColors[yw + x] = ColorLerpUnclamped(ColorLerpUnclamped(texColors[y1 + xFloor], texColors[y1 + xFloor + 1], xLerp),
                                                           ColorLerpUnclamped(texColors[y2 + xFloor], texColors[y2 + xFloor + 1], xLerp),
                                                           y * ratioY - yFloor);
                }
            }
        }

        private static Color ColorLerpUnclamped(Color c1, Color c2, float value)
        {
            return new Color(c1.r + (c2.r - c1.r) * value,
                              c1.g + (c2.g - c1.g) * value,
                              c1.b + (c2.b - c1.b) * value,
                              c1.a + (c2.a - c1.a) * value);
        }

        /// http://light11.hatenadiary.com/entry/2018/04/19/194015
        public static Texture2D GetResized(Texture2D texture, int width, int height)
        {
            // リサイズ後のサイズを持つRenderTextureを作成して書き込む
            var rt = RenderTexture.GetTemporary(width, height);
            Graphics.Blit(texture, rt);

            // リサイズ後のサイズを持つTexture2Dを作成してRenderTextureから書き込む
            var preRT = RenderTexture.active;
            RenderTexture.active = rt;
            var ret = new Texture2D(width, height);
            ret.ReadPixels(new Rect(0, 0, width, height), 0, 0);
            ret.Apply();
            RenderTexture.active = preRT;

            RenderTexture.ReleaseTemporary(rt);
            return ret;
        }
    }
}