SSEMessage.cs

using System.Text.Json.Serialization;

namespace SQLAgent.Hosting.Dto;

// ============================================
// SSE 消息类型定义（新架构：类似 ChatGPT/Claude）
// ============================================

/// <summary>
/// SSE 事件类型
/// </summary>
[JsonConverter(typeof(JsonStringEnumConverter))]
public enum SSEEventType
{
    delta,  // 增量文本（流式输出）
    block,  // 内容块（SQL、数据、图表等）
    done,   // 完成
    error   // 错误
}

/// <summary>
/// SSE 消息基类
/// </summary>
public abstract class SSEMessage
{
    /// <summary>
    /// 事件类型
    /// </summary>
    [JsonPropertyName("type")]
    public abstract SSEEventType Type { get; }
}

/// <summary>
/// 增量文本消息（流式文本输出）
/// </summary>
public class DeltaMessage : SSEMessage
{
    [JsonPropertyName("type")]
    public override SSEEventType Type => SSEEventType.delta;
    
    /// <summary>
    /// 增量文本内容
    /// </summary>
    [JsonPropertyName("delta")]
    public string Delta { get; set; } = string.Empty;
}

/// <summary>
/// 内容块消息
/// </summary>
public class BlockMessage : SSEMessage
{
    [JsonPropertyName("type")]
    public override SSEEventType Type => SSEEventType.block;
    
    /// <summary>
    /// 内容块
    /// </summary>
    [JsonPropertyName("block")]
    public ContentBlock Block { get; set; } = new SqlBlock();
}

/// <summary>
/// 错误消息
/// </summary>
public class ErrorMessage : SSEMessage
{
    [JsonPropertyName("type")]
    public override SSEEventType Type => SSEEventType.error;
    
    /// <summary>
    /// 错误代码
    /// </summary>
    [JsonPropertyName("code")]
    public string Code { get; set; } = string.Empty;
    
    /// <summary>
    /// 错误消息
    /// </summary>
    [JsonPropertyName("message")]
    public string Message { get; set; } = string.Empty;
    
    /// <summary>
    /// 详细信息
    /// </summary>
    [JsonPropertyName("details")]
    public string? Details { get; set; }
}

/// <summary>
/// 完成消息
/// </summary>
public class DoneMessage : SSEMessage
{
    [JsonPropertyName("type")]
    public override SSEEventType Type => SSEEventType.done;
    
    /// <summary>
    /// 执行耗时(毫秒)
    /// </summary>
    [JsonPropertyName("elapsedMs")]
    public long ElapsedMs { get; set; }
}

// ============================================
// 内容块类型定义
// ============================================

/// <summary>
/// 内容块类型
/// </summary>
[JsonConverter(typeof(JsonStringEnumConverter))]
public enum ContentBlockType
{
    Sql,    // SQL 代码
    Data,   // 数据表格
    Chart,  // 图表
    Error   // 错误
}

/// <summary>
/// 内容块基类
/// </summary>
[JsonPolymorphic(TypeDiscriminatorPropertyName = "type")]
[JsonDerivedType(typeof(SqlBlock), "sql")]
[JsonDerivedType(typeof(DataBlock), "data")]
[JsonDerivedType(typeof(ChartBlock), "chart")]
[JsonDerivedType(typeof(ErrorBlock), "error")]
public abstract class ContentBlock
{
    /// <summary>
    /// 块ID
    /// </summary>
    [JsonPropertyName("id")]
    public string Id { get; set; } = Guid.NewGuid().ToString();
}

/// <summary>
/// SQL 代码块
/// </summary>
public class SqlBlock : ContentBlock
{
    /// <summary>
    /// SQL 语句
    /// </summary>
    [JsonPropertyName("sql")]
    public string Sql { get; set; } = string.Empty;
    
    /// <summary>
    /// 涉及的表
    /// </summary>
    [JsonPropertyName("tables")]
    public string[] Tables { get; set; } = Array.Empty<string>();
    
    /// <summary>
    /// SQL 方言
    /// </summary>
    [JsonPropertyName("dialect")]
    public string? Dialect { get; set; }
}

/// <summary>
/// 数据表格块
/// </summary>
public class DataBlock : ContentBlock
{
    
    /// <summary>
    /// 列名
    /// </summary>
    [JsonPropertyName("columns")]
    public string[] Columns { get; set; } = Array.Empty<string>();
    
    /// <summary>
    /// 数据行
    /// </summary>
    [JsonPropertyName("rows")]
    public object[][] Rows { get; set; } = Array.Empty<object[]>();
    
    /// <summary>
    /// 总行数
    /// </summary>
    [JsonPropertyName("totalRows")]
    public int TotalRows { get; set; }
}

/// <summary>
/// 图表块
/// </summary>
public class ChartBlock : ContentBlock
{
    /// <summary>
    /// 图表类型
    /// </summary>
    [JsonPropertyName("chartType")]
    public string ChartType { get; set; } = "bar";
    
    /// <summary>
    /// ECharts option 配置 JSON 字符串
    /// </summary>
    [JsonPropertyName("echartsOption")]
    public string? EchartsOption { get; set; }
    
    /// <summary>
    /// 图表配置（兼容旧版）
    /// </summary>
    [JsonPropertyName("config")]
    public ChartConfig Config { get; set; } = new();
    
    /// <summary>
    /// 图表数据（兼容旧版）
    /// </summary>
    [JsonPropertyName("data")]
    public object Data { get; set; } = new { };
}

/// <summary>
/// 图表配置
/// </summary>
public class ChartConfig
{
    /// <summary>
    /// X轴字段
    /// </summary>
    [JsonPropertyName("xAxis")]
    public string? XAxis { get; set; }
    
    /// <summary>
    /// Y轴字段
    /// </summary>
    [JsonPropertyName("yAxis")]
    public string[]? YAxis { get; set; }
    
    /// <summary>
    /// 标题
    /// </summary>
    [JsonPropertyName("title")]
    public string? Title { get; set; }
    
    /// <summary>
    /// 显示图例
    /// </summary>
    [JsonPropertyName("showLegend")]
    public bool ShowLegend { get; set; } = true;
}

/// <summary>
/// 错误块
/// </summary>
public class ErrorBlock : ContentBlock
{
    /// <summary>
    /// 错误代码
    /// </summary>
    [JsonPropertyName("code")]
    public string Code { get; set; } = string.Empty;
    
    /// <summary>
    /// 错误消息
    /// </summary>
    [JsonPropertyName("message")]
    public string Message { get; set; } = string.Empty;
    
    /// <summary>
    /// 详细信息
    /// </summary>
    [JsonPropertyName("details")]
    public string? Details { get; set; }
}