using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using MelonLoader;
using MelonLoader.Utils;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

namespace ADOFAIRenderer.Data
{
    internal class RenderPreset
    {
        public string Name { get; set; } = string.Empty;
        public RenderConfig Config { get; set; } = null!;
    }

    internal static class PresetManager
    {
        private static string GetPresetsDirectory()
        {
            return Path.Combine(MelonEnvironment.GameRootDirectory, "UserData", "ADOFAIRenderer", "Presets");
        }

        private static string GetSafeFileName(string name)
        {
            return Path.GetInvalidFileNameChars().Aggregate(name, (current, c) => current.Replace(c, '_'));
        }

        public static void SavePreset(string name, RenderConfig config)
        {
            if (string.IsNullOrWhiteSpace(name))
            {
                throw new ArgumentException("프리셋 이름은 비어 있을 수 없습니다.");
            }

            string dir = GetPresetsDirectory();
            if (!Directory.Exists(dir))
            {
                Directory.CreateDirectory(dir);
            }

            var preset = new RenderPreset
            {
                Name = name,
                Config = config
            };

            string json = JsonConvert.SerializeObject(preset, Formatting.Indented);
            string safeName = GetSafeFileName(name);
            string filePath = Path.Combine(dir, safeName + ".json");
            File.WriteAllText(filePath, json);
        }

        public static List<RenderPreset> GetPresets()
        {
            var presets = new List<RenderPreset>();
            var dir = GetPresetsDirectory();
            
            if (!Directory.Exists(dir)) return presets;

            try
            {
                var files = Directory.GetFiles(dir, "*.json");
                foreach (var file in files)
                {
                    try
                    {
                        var json = File.ReadAllText(file);
                        var jObject = JsonConvert.DeserializeObject<JObject>(json);
                        if (jObject == null) continue;
                        
                        var configToken = jObject["Config"];
                        if (configToken is JObject configObj)
                        {
                            TryChangeKey(configObj, "DelayAfterLevelEnd", "DelayAfterEnd");
                            
                            // 1. legacy EncodingConfig -> VideoConfig
                            if (configObj["EncodingConfig"] is JObject oldEncodingConfigObj)
                            {
                                configObj["VideoConfig"] ??= oldEncodingConfigObj;
                                configObj.Remove("EncodingConfig");
                            }

                            // 2. legacy top-level Codec -> VideoConfig.Codec
                            var legacyCodecToken = configObj["Codec"];
                            if (legacyCodecToken != null && legacyCodecToken.Type != JTokenType.Null)
                            {
                                if (configObj["VideoConfig"] == null || configObj["VideoConfig"]!.Type == JTokenType.Null)
                                {
                                    configObj["VideoConfig"] = new JObject();
                                }
                                    
                                var videoConfigObj = (JObject)configObj["VideoConfig"]!;
                                videoConfigObj["Codec"] ??= legacyCodecToken;
                                    
                                configObj.Remove("Codec");
                            }

                            // 3. legacy top-level Audio properties -> AudioConfig
                            string[] legacyAudioProps = { "RenderAudio", "AudioSampleRate", "AudioChannels", "AudioBitrate" };
                            foreach (var prop in legacyAudioProps)
                            {
                                var legacyToken = configObj[prop];
                                if (legacyToken != null && legacyToken.Type != JTokenType.Null)
                                {
                                    if (configObj["AudioConfig"] == null || configObj["AudioConfig"]!.Type == JTokenType.Null)
                                    {
                                        configObj["AudioConfig"] = new JObject();
                                    }

                                    var audioConfigObj = (JObject)configObj["AudioConfig"]!;
                                    audioConfigObj[prop] ??= legacyToken;
                                }

                                configObj.Remove(prop);
                            }

                            if (configObj["AudioConfig"] != null && configObj["AudioConfig"]!.Type == JTokenType.Null)
                            {
                                configObj.Remove("AudioConfig");
                            }

                            // 4. legacy top-level Advanced properties -> AdvancedConfig
                            string[] legacyAdvancedProps = { "RandomSeed", "ProcessAudio", "NonTile" };
                            foreach (var prop in legacyAdvancedProps)
                            {
                                var legacyToken = configObj[prop];
                                if (legacyToken != null && legacyToken.Type != JTokenType.Null)
                                {
                                    if (configObj["AdvancedConfig"] == null || configObj["AdvancedConfig"]!.Type == JTokenType.Null)
                                    {
                                        configObj["AdvancedConfig"] = new JObject();
                                    }

                                    var advancedConfigObj = (JObject)configObj["AdvancedConfig"]!;
                                    advancedConfigObj[prop] ??= legacyToken;
                                }

                                configObj.Remove(prop);
                            }

                            if (configObj["AdvancedConfig"] != null && configObj["AdvancedConfig"]!.Type == JTokenType.Null)
                            {
                                configObj.Remove("AdvancedConfig");
                            }
                        }
                            
                        var preset = jObject.ToObject<RenderPreset>();
                        if (preset != null && !string.IsNullOrEmpty(preset.Name))
                        {
                            presets.Add(preset);
                        }
                    }
                    catch (Exception ex)
                    {
                        MelonLogger.Warning($"프리셋 파일 '{Path.GetFileName(file)}' 로드 중 오류 발생: {ex.Message}");
                    }
                }
            }
            catch (Exception ex)
            {
                MelonLogger.Error($"프리셋 목록을 불러오는 중 오류 발생: {ex.Message}");
            }

            return presets;
        }

        private static void TryChangeKey(JObject configObj, string keyBefore, string targetKey)
        {
            var legacyToken = configObj[keyBefore];
            if (legacyToken != null && legacyToken.Type != JTokenType.Null)
                configObj[targetKey] = legacyToken;

            configObj.Remove(keyBefore);
        }

        public static void DeletePreset(string name)
        {
            string dir = GetPresetsDirectory();
            string safeName = GetSafeFileName(name);
            string filePath = Path.Combine(dir, safeName + ".json");

            if (File.Exists(filePath))
            {
                File.Delete(filePath);
            }
        }
    }
}