heliosdb-nano 3.22.2

//! MCP Protocol types and serialization
//!
//! Implements the Model Context Protocol JSON-RPC format.

use serde::{Deserialize, Serialize};

/// JSON-RPC request
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct JsonRpcRequest {
    pub jsonrpc: String,
    pub id: Option<serde_json::Value>,
    pub method: String,
    #[serde(default)]
    pub params: serde_json::Value,
}

/// JSON-RPC response
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct JsonRpcResponse {
    pub jsonrpc: String,
    pub id: Option<serde_json::Value>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub result: Option<serde_json::Value>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub error: Option<JsonRpcError>,
}

impl JsonRpcResponse {
    pub fn success(id: Option<serde_json::Value>, result: serde_json::Value) -> Self {
        Self {
            jsonrpc: "2.0".to_string(),
            id,
            result: Some(result),
            error: None,
        }
    }

    pub fn error(id: Option<serde_json::Value>, code: i32, message: String) -> Self {
        Self {
            jsonrpc: "2.0".to_string(),
            id,
            result: None,
            error: Some(JsonRpcError {
                code,
                message,
                data: None,
            }),
        }
    }
}

/// JSON-RPC error
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct JsonRpcError {
    pub code: i32,
    pub message: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub data: Option<serde_json::Value>,
}

// Standard JSON-RPC error codes
pub const PARSE_ERROR: i32 = -32700;
pub const INVALID_REQUEST: i32 = -32600;
pub const METHOD_NOT_FOUND: i32 = -32601;
pub const INVALID_PARAMS: i32 = -32602;
pub const INTERNAL_ERROR: i32 = -32603;

/// MCP Server info
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ServerInfo {
    pub name: String,
    pub version: String,
}

/// MCP Capabilities
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Capabilities {
    #[serde(skip_serializing_if = "Option::is_none")]
    pub tools: Option<ToolsCapability>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub resources: Option<ResourcesCapability>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub prompts: Option<PromptsCapability>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ToolsCapability {
    #[serde(rename = "listChanged", skip_serializing_if = "Option::is_none")]
    pub list_changed: Option<bool>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ResourcesCapability {
    #[serde(rename = "listChanged", skip_serializing_if = "Option::is_none")]
    pub list_changed: Option<bool>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub subscribe: Option<bool>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PromptsCapability {
    #[serde(rename = "listChanged", skip_serializing_if = "Option::is_none")]
    pub list_changed: Option<bool>,
}

/// Initialize result
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct InitializeResult {
    #[serde(rename = "protocolVersion")]
    pub protocol_version: String,
    pub capabilities: Capabilities,
    #[serde(rename = "serverInfo")]
    pub server_info: ServerInfo,
}

/// Tool definition
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Tool {
    pub name: String,
    pub description: String,
    #[serde(rename = "inputSchema")]
    pub input_schema: serde_json::Value,
}

/// Tool result
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ToolResult {
    pub content: Vec<ToolContent>,
    #[serde(rename = "isError", skip_serializing_if = "Option::is_none")]
    pub is_error: Option<bool>,
}

impl ToolResult {
    pub fn text(text: String) -> Self {
        Self {
            content: vec![ToolContent::Text { text }],
            is_error: None,
        }
    }

    pub fn error(message: String) -> Self {
        Self {
            content: vec![ToolContent::Text { text: message }],
            is_error: Some(true),
        }
    }

    pub fn json<T: Serialize>(data: &T) -> Self {
        let text = serde_json::to_string_pretty(data).unwrap_or_else(|_| "{}".to_string());
        Self::text(text)
    }
}

/// Tool content types
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "type")]
pub enum ToolContent {
    #[serde(rename = "text")]
    Text { text: String },
    #[serde(rename = "image")]
    Image {
        data: String,
        #[serde(rename = "mimeType")]
        mime_type: String,
    },
    #[serde(rename = "resource")]
    Resource {
        resource: ResourceReference,
    },
}

/// Resource reference
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ResourceReference {
    pub uri: String,
    #[serde(rename = "mimeType", skip_serializing_if = "Option::is_none")]
    pub mime_type: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub text: Option<String>,
}

/// Resource definition
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Resource {
    pub uri: String,
    pub name: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub description: Option<String>,
    #[serde(rename = "mimeType", skip_serializing_if = "Option::is_none")]
    pub mime_type: Option<String>,
}

/// Resource content
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ResourceContent {
    pub uri: String,
    #[serde(rename = "mimeType", skip_serializing_if = "Option::is_none")]
    pub mime_type: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub text: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub blob: Option<String>,
}

/// Prompt definition
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Prompt {
    pub name: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub description: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub arguments: Option<Vec<PromptArgument>>,
}

/// Prompt argument
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PromptArgument {
    pub name: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub description: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub required: Option<bool>,
}

/// Prompt message
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PromptMessage {
    pub role: String,
    pub content: PromptContent,
}

/// Prompt content
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "type")]
pub enum PromptContent {
    #[serde(rename = "text")]
    Text { text: String },
    #[serde(rename = "image")]
    Image {
        data: String,
        #[serde(rename = "mimeType")]
        mime_type: String,
    },
    #[serde(rename = "resource")]
    Resource { resource: ResourceReference },
}