//! NAC Lens协议类型定义
//!
//! 定义NAC Lens协议的核心数据结构

use nac_udm::primitives::{Hash, Timestamp};
use serde::{Deserialize, Serialize};
use serde_json::Value;

/// NAC Lens请求
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct NacLensRequest {
    /// JSON-RPC版本（固定为"3.0"）
    pub jsonrpc: String,
    
    /// 请求ID
    pub id: RequestId,
    
    /// 方法名
    pub method: String,
    
    /// 参数
    pub params: Value,
    
    /// 时间戳（NAC扩展）
    #[serde(skip_serializing_if = "Option::is_none")]
    pub timestamp: Option<Timestamp>,
    
    /// 资产DNA哈希（NAC扩展）
    #[serde(skip_serializing_if = "Option::is_none")]
    pub dna_hash: Option<Hash>,
    
    /// 签名（NAC扩展）
    #[serde(skip_serializing_if = "Option::is_none")]
    pub signature: Option<String>,
}

/// NAC Lens响应
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct NacLensResponse {
    /// JSON-RPC版本
    pub jsonrpc: String,
    
    /// 请求ID
    pub id: RequestId,
    
    /// 结果（成功时）
    #[serde(skip_serializing_if = "Option::is_none")]
    pub result: Option<Value>,
    
    /// 错误（失败时）
    #[serde(skip_serializing_if = "Option::is_none")]
    pub error: Option<NAC Lens3Error>,
    
    /// 时间戳（NAC扩展）
    #[serde(skip_serializing_if = "Option::is_none")]
    pub timestamp: Option<Timestamp>,
    
    /// 服务器签名（NAC扩展）
    #[serde(skip_serializing_if = "Option::is_none")]
    pub server_signature: Option<String>,
}

/// NAC Lens错误
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct NAC Lens3Error {
    /// 错误代码
    pub code: i32,
    
    /// 错误消息
    pub message: String,
    
    /// 错误数据（可选）
    #[serde(skip_serializing_if = "Option::is_none")]
    pub data: Option<Value>,
}

/// 请求ID类型
#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash)]
#[serde(untagged)]
pub enum RequestId {
    /// 数字ID
    Number(u64),
    
    /// 字符串ID
    String(String),
    
    /// 空ID（通知）
    Null,
}

/// NAC Lens批量请求
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct NAC Lens3BatchRequest {
    /// 批量请求列表
    pub requests: Vec<NacLensRequest>,
}

/// NAC Lens批量响应
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct NAC Lens3BatchResponse {
    /// 批量响应列表
    pub responses: Vec<NacLensResponse>,
}

/// NAC Lens错误代码
pub mod error_codes {
    /// 解析错误
    pub const PARSE_ERROR: i32 = -32700;
    
    /// 无效请求
    pub const INVALID_REQUEST: i32 = -32600;
    
    /// 方法不存在
    pub const METHOD_NOT_FOUND: i32 = -32601;
    
    /// 无效参数
    pub const INVALID_PARAMS: i32 = -32602;
    
    /// 内部错误
    pub const INTERNAL_ERROR: i32 = -32603;
    
    /// 服务器错误范围
    pub const SERVER_ERROR_START: i32 = -32000;
    pub const SERVER_ERROR_END: i32 = -32099;
    
    // NAC扩展错误代码
    
    /// 时间戳过期
    pub const TIMESTAMP_EXPIRED: i32 = -33001;
    
    /// DNA验证失败
    pub const DNA_VERIFICATION_FAILED: i32 = -33002;
    
    /// 签名无效
    pub const INVALID_SIGNATURE: i32 = -33003;
    
    /// 合规检查失败
    pub const COMPLIANCE_CHECK_FAILED: i32 = -33004;
    
    /// 权限不足
    pub const INSUFFICIENT_PERMISSIONS: i32 = -33005;
}

impl NacLensRequest {
    /// 创建新请求
    pub fn new(id: RequestId, method: impl Into<String>, params: Value) -> Self {
        Self {
            jsonrpc: "3.0".to_string(),
            id,
            method: method.into(),
            params,
            timestamp: Some(Timestamp::now()),
            dna_hash: None,
            signature: None,
        }
    }
    
    /// 验证请求
    pub fn validate(&self) -> Result<(), String> {
        if self.jsonrpc != "3.0" {
            return Err("Invalid JSON-RPC version".to_string());
        }
        
        if self.method.is_empty() {
            return Err("Method name cannot be empty".to_string());
        }
        
        // 验证时间戳（如果存在）
        if let Some(ts) = self.timestamp {
            let now = Timestamp::now();
            let diff = if now > ts { now - ts } else { ts - now };
            
            // 允许5分钟的时间偏差
            if diff > 300 {
                return Err("Timestamp expired or too far in future".to_string());
            }
        }
        
        Ok(())
    }
}

impl NacLensResponse {
    /// 创建成功响应
    pub fn success(id: RequestId, result: Value) -> Self {
        Self {
            jsonrpc: "3.0".to_string(),
            id,
            result: Some(result),
            error: None,
            timestamp: Some(Timestamp::now()),
            server_signature: None,
        }
    }
    
    /// 创建错误响应
    pub fn error(id: RequestId, code: i32, message: impl Into<String>) -> Self {
        Self {
            jsonrpc: "3.0".to_string(),
            id,
            result: None,
            error: Some(NAC Lens3Error {
                code,
                message: message.into(),
                data: None,
            }),
            timestamp: Some(Timestamp::now()),
            server_signature: None,
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use serde_json::json;
    
    #[test]
    fn test_request_creation() {
        let req = NacLensRequest::new(
            RequestId::Number(1),
            "test_method",
            json!({"param": "value"}),
        );
        
        assert_eq!(req.jsonrpc, "3.0");
        assert_eq!(req.method, "test_method");
        assert!(req.timestamp.is_some());
    }
    
    #[test]
    fn test_request_validation() {
        let req = NacLensRequest::new(
            RequestId::Number(1),
            "test_method",
            json!({}),
        );
        
        assert!(req.validate().is_ok());
    }
    
    #[test]
    fn test_response_creation() {
        let resp = NacLensResponse::success(
            RequestId::Number(1),
            json!({"result": "success"}),
        );
        
        assert_eq!(resp.jsonrpc, "3.0");
        assert!(resp.result.is_some());
        assert!(resp.error.is_none());
    }
}