using System.Collections.Generic;
using System.Text;
using AlicizaX.Editor;
using UnityEditor;
using UnityEngine;
using UnityEngine.UIElements;
using UnityEditorInternal;

namespace AlicizaX.Localization.Editor
{
    internal class LocalizationSettingsProvider : UnityEditor.SettingsProvider
    {
        private SerializedObject _serializedObject;
        private SerializedProperty _languageTypes;
        private ReorderableList _languageList;
        private SerializedProperty _genLangaugeTypePath;
        private SerializedProperty generateScriptCodeFirstConfig;
        private List<string> popConfig = new List<string>();

        public LocalizationSettingsProvider() : base("Project/Localization Settings", SettingsScope.Project)
        {
        }

        public override void OnActivate(string searchContext, VisualElement rootElement)
        {
            InitGUI();
        }

        private void InitGUI()
        {
            var setting = LocalizationConfiguration.Instance;
            _serializedObject?.Dispose();
            _serializedObject = new SerializedObject(setting);
            _languageTypes = _serializedObject.FindProperty("LanguageTypes");
            _genLangaugeTypePath = _serializedObject.FindProperty("_genLangaugeTypePath");
            generateScriptCodeFirstConfig = _serializedObject.FindProperty("generateScriptCodeFirstConfig");
            // 自定义 ReorderableList
            _languageList = new ReorderableList(_serializedObject, _languageTypes,
                draggable: false,
                displayHeader: true,
                displayAddButton: true,
                displayRemoveButton: true);

            _languageList.drawHeaderCallback = rect => { EditorGUI.LabelField(rect, "Language Types"); };

            _languageList.drawElementCallback = (rect, index, isActive, isFocused) =>
            {
                var element = _languageTypes.GetArrayElementAtIndex(index);
                rect.y += 2;

                if (index < 2) // 前两个（中文、英文）禁止修改
                {
                    EditorGUI.BeginDisabledGroup(true);
                    EditorGUI.TextField(
                        new Rect(rect.x, rect.y, rect.width, EditorGUIUtility.singleLineHeight),
                        element.stringValue);
                    EditorGUI.EndDisabledGroup();
                }
                else
                {
                    element.stringValue = EditorGUI.TextField(
                        new Rect(rect.x, rect.y, rect.width, EditorGUIUtility.singleLineHeight),
                        element.stringValue);
                }
            };

            // 禁止删除前两个
            _languageList.onCanRemoveCallback = list =>
            {
                return list.index >= 2; // 只有索引 >=2 的项才能删除
            };
            popConfig.Clear();
            if (setting.LanguageTypeNames.Count > 0)
            {
                foreach (var lang in setting.LanguageTypeNames)
                {
                    string name = lang.Or("Unknown");
                    popConfig.Add(name);
                }
            }
        }

        public override void OnGUI(string searchContext)
        {
            if (_serializedObject == null || !_serializedObject.targetObject)
            {
                InitGUI();
            }

            _serializedObject.Update();
            EditorGUI.BeginChangeCheck();

            EditorGUILayout.PropertyField(_genLangaugeTypePath);
            EditorDrawing.DrawStringSelectPopup(new GUIContent("Gen Lang"), new GUIContent("None"), popConfig.ToArray(), generateScriptCodeFirstConfig.stringValue,
                (e) =>
                {
                    generateScriptCodeFirstConfig.stringValue = e;
                    _serializedObject.ApplyModifiedProperties();
                    LocalizationConfiguration.Save();
                });
            if (GUILayout.Button("Generate Language Types"))
            {
                RegenerateLanguageTypes();
            }

            _languageList.DoLayoutList();

            if (EditorGUI.EndChangeCheck())
            {
                _serializedObject.ApplyModifiedProperties();
                LocalizationConfiguration.Save();
            }
        }

        private void RegenerateLanguageTypes()
        {
            StringBuilder sb = new StringBuilder();

            sb.AppendLine("using System.Collections.Generic;");
            sb.AppendLine("");
            sb.AppendLine("/// <summary>");
            sb.AppendLine("/// AutoGenerate");
            sb.AppendLine("/// </summary>");
            sb.AppendLine("public static class LanguageTypes");
            sb.AppendLine("{");
            sb.AppendLine("\tpublic static readonly IReadOnlyList<string> Types = new List<string>");
            sb.AppendLine("\t{");
            for (int i = 0; i < LocalizationConfiguration.Instance.LanguageTypeNames.Count; i++)
            {
                sb.AppendLine($"\t\t\"{LocalizationConfiguration.Instance.LanguageTypeNames[i]}\",");
            }

            sb.AppendLine("\t};");

            sb.AppendLine("");
            sb.AppendLine("\tpublic static string IndexToString(int index)");
            sb.AppendLine("\t{");
            sb.AppendLine("\t\tif (index < 0 || index >= Types.Count) return \"Unknown\";");
            sb.AppendLine("\t\treturn Types[index];");
            sb.AppendLine("\t}");
            sb.AppendLine("");
            sb.AppendLine("\tpublic static int StringToIndex(string s)");
            sb.AppendLine("\t{");
            sb.AppendLine("\t\tint index = -1;");
            sb.AppendLine("\t\tfor (int i = 0; i < Types.Count; i++)");
            sb.AppendLine("\t\t{");
            sb.AppendLine("\t\t\tif (Types[i] == s)");
            sb.AppendLine("\t\t\t{");
            sb.AppendLine("\t\t\t\tindex = i;");
            sb.AppendLine("\t\t\t\tbreak;");
            sb.AppendLine("\t\t\t}");
            sb.AppendLine("\t\t}");
            sb.AppendLine("");
            sb.AppendLine("\t\treturn index;");
            sb.AppendLine("\t}");
            sb.AppendLine("");
            sb.AppendLine("}");

            System.IO.File.WriteAllText(_genLangaugeTypePath.stringValue, sb.ToString());
            AssetDatabase.Refresh();
        }

        public override void OnDeactivate()
        {
            base.OnDeactivate();
            LocalizationConfiguration.Save();
        }

        static LocalizationSettingsProvider s_provider;

        [SettingsProvider]
        public static SettingsProvider CreateMyCustomSettingsProvider()
        {
            if (s_provider == null)
            {
                s_provider = new LocalizationSettingsProvider();
            }

            return s_provider;
        }
    }
}