using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Text.Json.Serialization;

namespace CoreAgent.Domain.Entities
{
    /// <summary>
    /// 网络配置聚合根
    /// </summary>
    public class NetworkConfiguration : IValidatableObject
    {
        /// <summary>
        /// 配置键值
        /// </summary>
        [Required(ErrorMessage = "配置键值不能为空")]
        [JsonPropertyName("configKey")]
        public string ConfigKey { get; set; }

        /// <summary>
        /// RAN配置文件路径
        /// </summary>
        [Required(ErrorMessage = "RAN配置路径不能为空")]
        [JsonPropertyName("ragConfig")]
        public string RagConfig { get; set; }

        /// <summary>
        /// 核心网和IMS配置列表
        /// </summary>
        [JsonPropertyName("coreOrImsConfigs")]
        public List<CoreImsConfig> CoreOrImsConfigs { get; set; }

        /// <summary>
        /// APN配置
        /// </summary>
        [Required(ErrorMessage = "APN配置不能为空")]
        [JsonPropertyName("apn")]
        public string Apn { get; set; }

        /// <summary>
        /// 频段配置
        /// </summary>
        [Required(ErrorMessage = "频段配置不能为空")]
        [MinLength(1, ErrorMessage = "至少需要一个频段配置")]
        [JsonPropertyName("band")]
        public List<string> Band { get; set; }

        /// <summary>
        /// 配置说明
        /// </summary>
        [JsonPropertyName("comment")]
        public string Comment { get; set; }

        /// <summary>
        /// 构造函数
        /// </summary>
        [JsonConstructor]
        public NetworkConfiguration()
        {
            CoreOrImsConfigs = new List<CoreImsConfig>();
            Band = new List<string>();
        }

        /// <summary>
        /// 创建新的网络配置
        /// </summary>
        public static NetworkConfiguration Create(
            string configKey,
            string ragConfig,
            List<CoreImsConfig> coreOrImsConfigs,
            string apn,
            List<string> band,
            string comment = null)
        {
            var config = new NetworkConfiguration
            {
                ConfigKey = configKey,
                RagConfig = ragConfig,
                Apn = apn,
                Comment = comment,
                CoreOrImsConfigs = coreOrImsConfigs ?? new List<CoreImsConfig>(),
                Band = band ?? new List<string>()
            };

            var validationResults = new List<ValidationResult>();
            if (!Validator.TryValidateObject(config, new ValidationContext(config), validationResults, true))
            {
                throw new ValidationException(string.Join(Environment.NewLine, validationResults.Select(r => r.ErrorMessage)));
            }

            return config;
        }

        /// <summary>
        /// 验证配置
        /// </summary>
        public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
        {
            // 验证PLMN是否重复
            var plmnGroups = CoreOrImsConfigs.GroupBy(x => x.Plmn);
            foreach (var group in plmnGroups)
            {
                if (group.Count() > 1)
                {
                    yield return new ValidationResult($"PLMN {group.Key} 重复配置");
                }
            }

            // 验证索引是否连续
            var orderedConfigs = CoreOrImsConfigs.OrderBy(x => x.Index).ToList();
            for (int i = 0; i < orderedConfigs.Count; i++)
            {
                if (orderedConfigs[i].Index != i + 1)
                {
                    yield return new ValidationResult($"配置索引不连续，期望 {i + 1}，实际 {orderedConfigs[i].Index}");
                }
            }

            // 验证频段格式
            foreach (var band in Band)
            {
                if (!band.StartsWith("B") || !int.TryParse(band.Substring(1), out _))
                {
                    yield return new ValidationResult($"频段格式不正确: {band}，应为 B1、B2 等格式");
                }
            }
        }

        /// <summary>
        /// 获取指定PLMN的配置
        /// </summary>
        public CoreImsConfig GetConfigByPlmn(string plmn)
        {
            return CoreOrImsConfigs.FirstOrDefault(x => x.Plmn == plmn);
        }

        /// <summary>
        /// 获取指定索引的配置
        /// </summary>
        public CoreImsConfig GetConfigByIndex(int index)
        {
            return CoreOrImsConfigs.FirstOrDefault(x => x.Index == index);
        }
    }

    /// <summary>
    /// 网络配置包装类
    /// </summary>
    public class NetworkConfigurationsWrapper
    {
        /// <summary>
        /// 网络配置列表
        /// </summary>
        [JsonPropertyName("networkConfigurations")]
        public List<NetworkConfiguration> NetworkConfigurations { get; set; } = new List<NetworkConfiguration>();
    }

    /// <summary>
    /// 核心网和IMS配置实体
    /// </summary>
    public class CoreImsConfig
    {
        /// <summary>
        /// 配置索引
        /// </summary>
        [Required(ErrorMessage = "配置索引不能为空")]
        [Range(1, int.MaxValue, ErrorMessage = "配置索引必须大于0")]
        [JsonPropertyName("index")]
        public int Index { get; set; }

        /// <summary>
        /// PLMN码
        /// </summary>
        [Required(ErrorMessage = "PLMN码不能为空")]
        [RegularExpression(@"^\d{5,6}$", ErrorMessage = "PLMN码必须是5-6位数字")]
        [JsonPropertyName("plmn")]
        public string Plmn { get; set; }

        /// <summary>
        /// 核心网配置文件路径
        /// </summary>
        [Required(ErrorMessage = "核心网配置路径不能为空")]
        [RegularExpression(@"^Config/CoreNetwork/.*\.cfg$", ErrorMessage = "核心网配置路径格式不正确")]
        [JsonPropertyName("coreNetworkConfig")]
        public string CoreNetworkConfig { get; set; }

        /// <summary>
        /// IMS配置文件路径
        /// </summary>
        [Required(ErrorMessage = "IMS配置路径不能为空")]
        [RegularExpression(@"^Config/Ims/.*\.cfg$", ErrorMessage = "IMS配置路径格式不正确")]
        [JsonPropertyName("imsConfig")]
        public string ImsConfig { get; set; }
    }
}