// <auto-generated/>
// ReSharper disable All
// Disable StyleCop analysis for this file
// <copyright file="TransformerService.cs" company="Manus">
// Copyright (c) Manus. All rights reserved.
// </copyright>

using medical.transfomer.dto;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json;
using System.Text.Json.Nodes;

namespace medical.insu.transfomer
{
    /// <summary>
    /// JSON配置转换服务类
    /// </summary>
    public class TransformerService
    {
        private readonly TransformationConfig _config;
        private readonly IValueConverter _valueConverter; // 用于字典转换等

        /// <summary>
        /// 构造函数
        /// </summary>
        /// <param name="configuration">转换配置</param>
        /// <param name="valueConverter">值转换器实例 (可选)</param>
        public TransformerService(TransformationConfig configuration, IValueConverter valueConverter = null)
        { 
            _config = configuration ?? throw new ArgumentNullException(nameof(configuration));
            _valueConverter = valueConverter ?? new DefaultValueConverter(); // 提供一个默认实现
        }

        /// <summary>
        /// 从JSON字符串加载配置
        /// </summary>
        /// <param name="jsonConfig">包含配置的JSON字符串</param>
        /// <returns>TransformationConfig 实例</returns>
        public static TransformationConfig LoadConfigFromJson(string jsonConfig)
        {
            if (string.IsNullOrWhiteSpace(jsonConfig))
            {
                throw new ArgumentException("JSON configuration string cannot be null or empty.", nameof(jsonConfig));
            }
            try
            {
                return JsonSerializer.Deserialize<TransformationConfig>(jsonConfig, new JsonSerializerOptions
                {
                    PropertyNameCaseInsensitive = true // 允许属性名不区分大小写
                });
            }
            catch (JsonException ex)
            {
                // 在实际应用中，这里应该记录更详细的错误日志
                throw new InvalidOperationException("Failed to deserialize JSON configuration.", ex);
            }
        }

        /// <summary>
        /// 将源数据对象根据指定方法转换为目标JSON字符串 (系统对象 -> 接口JSON)
        /// </summary>
        /// <param name="methodName">方法名称 (来自 method_config)</param>
        /// <param name="sourceObject">源数据对象 (通常是一个C#对象或字典)</param>
        /// <returns>转换后的JSON字符串</returns>
        public string Transform(string methodName, object sourceObject)
        {   
            // 1. 查找方法配置
            var method = _config.MethodConfigs.FirstOrDefault(m => m.METHOD_NAME == methodName);
            if (method == null)
            {
                throw new ArgumentException($"Method '{methodName}' not found in configuration.", nameof(methodName));
            }

            // 2. 筛选出适用于当前方法和出参的组装规则 (parametr_type = 2 代表出参)
            var assemblyRules = _config.ObjectAssemblies
                .Where(a => a.METHOD_REF == method.METHOD_ID && a.PARAMETR_TYPE == 2 && a.ASSEMBLY_TYPE == "interface") // 假设是系统到接口的转换
                .OrderBy(a => a.OBJECT_PATH) // 排序以确保父节点先创建
                .ToList();

            if (!assemblyRules.Any())
            {
                // 如果没有找到针对出参的interface类型组装规则，可能需要抛出错误或返回空JSON
                // 根据实际需求，这里也可以查找 'sys' 类型的规则，取决于转换方向的定义
                Console.WriteLine($"Warning: No 'interface' assembly rules found for method '{methodName}' and parameter type 2 (output).");
                return "{}"; // 或者抛出异常
            }

            var rootNode = new JsonObject(); // 创建JSON根节点

            // 3. 遍历组装规则，构建JSON
            foreach (var rule in assemblyRules)
            {
                // 3.1 查找对应的映射规则 (通过MappingTable关联到ObjectMapping的ObjectTableName或MappingId)
                // 假设 MappingTable 直接对应 ObjectMapping 中的 ObjectTableName
                var mapping = _config.ObjectMappings.FirstOrDefault(om => om.OBJECT_TABLE_NAME == rule.MAPPING_TABLE && om.INTERFACE_FIELD != null);
                
                // 如果MappingTable也可能是MappingId, 则需要调整查找逻辑
                // var mapping = _config.ObjectMappings.FirstOrDefault(om => 
                //    (om.ObjectTableName == rule.MappingTable || om.MappingId == rule.MappingTable) && 
                //    om.InterfaceField != null);

                if (mapping == null)
                {
                    Console.WriteLine($"Warning: No object mapping found for MappingTable '{rule.MAPPING_TABLE}' in assembly rule '{rule.ID}'. Skipping path '{rule.OBJECT_PATH}'.");
                    continue;
                }

                // 3.2 从源对象获取值
                // 这里简化处理，假设sourceObject是字典或可以通过反射获取属性
                // 实际应用中需要更健壮的取值逻辑
                object sourceValue = GetValueFromSourceObject(sourceObject, mapping.SYSTEM_FIELD);

                if (sourceValue == null && rule.OBJECT_PATH.Contains("patientId")) // 示例：特定字段的空值处理
                {
                     // Console.WriteLine($"Debug: Source value for {mapping.SystemField} is null.");
                }

                // 3.3 值转换 (字典翻译、类型转换等)
                object convertedValue = _valueConverter.Convert(
                    sourceValue,
                    mapping.SYSTEM_FIELD_TYPE?.ToString(), // Convert decimal? to string
                    mapping.OBJECT_FIELD_TYPE?.ToString(), // Convert decimal? to string
                    mapping.SYSTEM_DICT_NAME,
                    mapping.OBJECT_DICT_NAME,
                    rule.PARAMETR_TYPE
                );

                // 3.4 根据ObjectPath设置值到JSON节点
                SetValueByJsonPath(rootNode, rule.OBJECT_PATH, convertedValue, rule.OBJECT_TYPE);
            }

            return rootNode.ToJsonString(new JsonSerializerOptions { WriteIndented = true });
        }

        /// <summary>
        /// 从源对象中获取指定属性的值 (简化实现)
        /// </summary>
        private object GetValueFromSourceObject(object source, string propertyName)
        {
            if (source == null || string.IsNullOrEmpty(propertyName)) return null;

            if (source is IDictionary<string, object> dictSource)
            {
                return dictSource.TryGetValue(propertyName, out var val) ? val : null;
            }
            if (source is JsonElement jsonElementSource && jsonElementSource.ValueKind == JsonValueKind.Object)
            {
                return jsonElementSource.TryGetProperty(propertyName, out var prop) ? GetValueFromJsonElement(prop) : null;
            }
            
            // 尝试通过反射获取属性值
            var propInfo = source.GetType().GetProperty(propertyName);
            if (propInfo != null)
            {
                return propInfo.GetValue(source);
            }
            // 如果是JsonNode,尝试获取
            if (source is JsonNode jnSource)
            {
                var parts = propertyName.Split(new[] { '.' }, StringSplitOptions.RemoveEmptyEntries);
                JsonNode currentNode = jnSource;
                foreach (var part in parts)
                {
                    if (currentNode is JsonObject jo && jo.ContainsKey(part))
                    {
                        currentNode = jo[part];
                    }
                    else
                    {
                        return null; // 路径不存在
                    }
                }
                if (currentNode is JsonValue jv) return jv.GetValue<object>();
                return currentNode; //可能是JsonObject或JsonArray
            }

            Console.WriteLine($"Warning: Property '{propertyName}' not found in source object of type '{source.GetType().Name}'.");
            return null;
        }
        
        private object GetValueFromJsonElement(JsonElement element)
        {
            switch (element.ValueKind)
            {
                case JsonValueKind.String: return element.GetString();
                case JsonValueKind.Number: 
                    if (element.TryGetInt32(out int i)) return i;
                    if (element.TryGetInt64(out long l)) return l;
                    if (element.TryGetDouble(out double d)) return d;
                    return element.GetDecimal(); // Fallback
                case JsonValueKind.True: return true;
                case JsonValueKind.False: return false;
                case JsonValueKind.Null: return null;
                case JsonValueKind.Object: return element; // Or parse to dictionary
                case JsonValueKind.Array: return element; // Or parse to list
                default: return null;
            }
        }

        /// <summary>
        /// 根据JSONPath在JsonNode中设置值 (简化实现, 支持基本的路径)
        /// </summary>
        private void SetValueByJsonPath(JsonNode rootNode, string path, object value, int objectType)
        {
            if (string.IsNullOrWhiteSpace(path) || rootNode == null) return;

            // 移除起始的 "$."
            if (path.StartsWith("$."))
            {
                path = path.Substring(2);
            }

            var segments = path.Split('.');
            JsonNode currentNode = rootNode;

            for (int i = 0; i < segments.Length - 1; i++)
            {
                var segment = segments[i];
                if (currentNode[segment] == null)
                {
                    // 根据下一个segment是否是数组索引来决定创建JsonObject还是JsonArray
                    // 此处简化：如果下一个路径是数字，则认为是数组索引，但设计文档中object_type更可靠
                    // 暂时简单处理，都创建JsonObject，实际应根据object_assembly的object_type判断
                    currentNode[segment] = new JsonObject(); 
                }
                currentNode = currentNode[segment];
                if (currentNode == null) // 防御性编程，如果中间节点创建失败或路径无效
                {
                    Console.WriteLine($"Error: Could not navigate or create path segment '{segment}' in JSON path '{path}'.");
                    return;
                }
            }

            var lastSegment = segments.Last();
            JsonNode valueNode = value == null ? null : JsonValue.Create(value); // JsonValue.Create可以处理多种基本类型
            
            if (value is JsonElement je)
            {
                 valueNode = JsonNode.Parse(je.GetRawText());
            }
            else if (value is IDictionary<string, object> dictValue)
            {
                valueNode = new JsonObject();
                foreach(var kvp in dictValue)
                {
                    ((JsonObject)valueNode).Add(kvp.Key, JsonValue.Create(kvp.Value));
                }
            }
            else if (value is IEnumerable<object> listValue && !(value is string)) // 确保不是字符串
            {
                var jsonArray = new JsonArray();
                foreach (var item in listValue)
                {
                    jsonArray.Add(JsonValue.Create(item));
                }
                valueNode = jsonArray;
            }

            if (objectType == 2) // 列表类型
            {
                if (currentNode[lastSegment] == null || !(currentNode[lastSegment] is JsonArray))
                {
                    currentNode[lastSegment] = new JsonArray();
                }
                ((JsonArray)currentNode[lastSegment]).Add(valueNode);
            }
            else // 对象类型
            {
                ((JsonObject)currentNode)[lastSegment] = valueNode;
            }
        }

        /// <summary>
        /// 将接口JSON字符串根据指定方法转换为目标系统对象 (接口JSON -> 系统对象)
        /// </summary>
        /// <typeparam name="T">期望的目标系统对象类型</typeparam>
        /// <param name="methodName">方法名称 (来自 method_config)</param>
        /// <param name="sourceJson">源JSON字符串</param>
        /// <returns>转换后的目标系统对象</returns>
        public T Transform<T>(string methodName, string sourceJson) where T : new()
        {
            // 1. 查找方法配置
            var method = _config.MethodConfigs.FirstOrDefault(m => m.METHOD_NAME == methodName);
            if (method == null)
            {
                throw new ArgumentException($"Method '{methodName}' not found in configuration.", nameof(methodName));
            }

            // 2. 解析源JSON
            JsonNode sourceNode;
            try
            {
                sourceNode = JsonNode.Parse(sourceJson);
            }
            catch (JsonException ex)
            {
                throw new ArgumentException("Invalid source JSON string.", nameof(sourceJson), ex);
            }
            if (sourceNode == null) throw new ArgumentException("Parsed source JSON is null.", nameof(sourceJson));

            // 3. 筛选出适用于当前方法和入参的组装规则 (parametr_type = 1 代表入参)
            var assemblyRules = _config.ObjectAssemblies
                .Where(a => a.METHOD_REF == method.METHOD_ID && a.PARAMETR_TYPE == 1 && a.ASSEMBLY_TYPE == "sys") // 假设是接口到系统的转换
                .OrderBy(a => a.OBJECT_PATH)
                .ToList();
            
            if (!assemblyRules.Any())
            {
                Console.WriteLine($"Warning: No 'sys' assembly rules found for method '{methodName}' and parameter type 1 (input).");
                return new T(); // 或者抛出异常
            }

            T targetObject = new T();

            // 4. 遍历组装规则, 填充目标对象
            foreach (var rule in assemblyRules)
            {
                var mapping = _config.ObjectMappings.FirstOrDefault(om => om.OBJECT_TABLE_NAME == rule.MAPPING_TABLE && om.SYSTEM_FIELD != null);
                if (mapping == null)
                {
                    Console.WriteLine($"Warning: No object mapping found for MappingTable '{rule.MAPPING_TABLE}' in assembly rule '{rule.ID}'. Skipping path '{rule.OBJECT_PATH}'.");
                    continue;
                }

                // 4.1 从源JSON获取值
                object sourceValue = GetValueByJsonPath(sourceNode, rule.OBJECT_PATH);

                // 4.2 值转换
                object convertedValue = _valueConverter.Convert(sourceValue, mapping.OBJECT_FIELD_TYPE, mapping.SYSTEM_FIELD_TYPE, mapping.OBJECT_DICT_NAME, mapping.SYSTEM_DICT_NAME, rule.PARAMETR_TYPE);
                
                // 4.3 设置到目标对象属性 (简化实现, 假设属性名与SystemField一致)
                // 实际应用中可能需要更复杂的属性设置逻辑，例如处理嵌套对象
                var propInfo = typeof(T).GetProperty(mapping.SYSTEM_FIELD);
                if (propInfo != null && propInfo.CanWrite)
                {
                    try
                    {
                        // 类型转换，确保赋的值与属性类型匹配
                        var typedValue = ConvertToPropertyType(convertedValue, propInfo.PropertyType);
                        propInfo.SetValue(targetObject, typedValue);
                    }
                    catch (Exception ex)
                    {
                        Console.WriteLine($"Error setting property '{mapping.SYSTEM_FIELD}': {ex.Message}");
                    }
                }
                else
                {
                    Console.WriteLine($"Warning: Property '{mapping.SYSTEM_FIELD}' not found or not writable on type '{typeof(T).Name}'.");
                }
            }
            return targetObject;
        }

        /// <summary>
        /// 根据JSONPath从JsonNode中获取值 (简化实现)
        /// </summary>
        private object GetValueByJsonPath(JsonNode rootNode, string path)
        {
            if (string.IsNullOrWhiteSpace(path) || rootNode == null) return null;
            if (path.StartsWith("$.")) path = path.Substring(2);

            var segments = path.Split('.');
            JsonNode currentNode = rootNode;
            foreach (var segment in segments)
            {
                if (currentNode is JsonObject jo && jo.ContainsKey(segment))
                {
                    currentNode = jo[segment];
                }
                // TODO: Add support for array indexing if needed, e.g., "items[0].name"
                else
                {
                    return null; // 路径不存在
                }
            }
            if (currentNode is JsonValue jv) return jv.GetValue<object>(); // GetValue<object> 会尝试转换为合适的.NET类型
            return currentNode; //可能是JsonObject或JsonArray，调用者需要进一步处理
        }

        /// <summary>
        /// 将值转换为目标属性类型 (简化实现)
        /// </summary>
        private object ConvertToPropertyType(object value, Type targetType)
        {
            if (value == null) return null;
            if (targetType.IsAssignableFrom(value.GetType())) return value;
            try
            {
                return Convert.ChangeType(value, targetType);
            }
            catch
            {
                // 对于复杂类型或JsonElement，可能需要特殊处理
                if (value is JsonElement je && targetType == typeof(string)) return je.ToString();
                // 添加更多转换逻辑...
                return null; 
            }
        }
    }

    /// <summary>
    /// 值转换器接口 (用于字典翻译、类型转换等)
    /// </summary>
    public interface IValueConverter
    {
        /// <summary>
        /// 执行值转换
        /// </summary>
        /// <param name="sourceValue">源值</param>
        /// <param name="sourceType">源类型字符串 (来自配置)</param>
        /// <param name="targetType">目标类型字符串 (来自配置)</param>
        /// <param name="sourceDictName">源字典名称 (来自配置)</param>
        /// <param name="targetDictName">目标字典名称 (来自配置)</param>
        /// <param name="paramDirection">参数方向 (1入参，2出参)</param>
        /// <returns>转换后的值</returns>
        object Convert(object sourceValue, string sourceType, string targetType, string sourceDictName, string targetDictName, int paramDirection);
        object Convert(object sourceValue, decimal? oBJECT_FIELD_TYPE, decimal? sYSTEM_FIELD_TYPE, string oBJECT_DICT_NAME, string sYSTEM_DICT_NAME, int pARAMETR_TYPE);
    }

    /// <summary>
    /// 默认的值转换器实现 (简单类型转换，无字典转换)
    /// </summary>
    public class DefaultValueConverter : IValueConverter
    {
        public object Convert(object sourceValue, string sourceType, string targetType, string sourceDictName, string targetDictName, int paramDirection)
        {
            // 简单示例：如果类型字符串匹配C#类型，尝试转换  
            if (sourceValue == null) return null;

            try
            {
                Type targetTypeResolved = Type.GetType(targetType) ?? typeof(object);
                return System.Convert.ChangeType(sourceValue, targetTypeResolved);
            }
            catch
            {
                return sourceValue;
            }
        }

        public object Convert(object sourceValue, decimal? objectFieldType, decimal? systemFieldType, string objectDictName, string systemDictName, int paramDirection)
        {
            // 示例实现：直接返回源值，实际应用中需要根据字段类型和字典名称进行转换  
            return sourceValue;
        }
    }
}