//! MCP (Model Context Protocol) support
//!
//! Implements MCP client and server for tool/resource integration.

use async_trait::async_trait;
use serde::{Deserialize, Serialize};
use std::collections::HashMap;
use zclaw_types::Result;

/// MCP tool definition
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpTool {
    pub name: String,
    pub description: String,
    pub input_schema: serde_json::Value,
}

/// MCP resource definition
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpResource {
    pub uri: String,
    pub name: String,
    pub description: Option<String>,
    pub mime_type: Option<String>,
}

/// MCP prompt definition
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpPrompt {
    pub name: String,
    pub description: String,
    pub arguments: Vec<McpPromptArgument>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpPromptArgument {
    pub name: String,
    pub description: String,
    pub required: bool,
}

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

/// MCP client configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpClientConfig {
    pub server_url: String,
    pub server_info: McpServerInfo,
    pub capabilities: McpCapabilities,
}

#[derive(Debug, Clone, Serialize, Deserialize, Default)]
pub struct McpCapabilities {
    pub tools: Option<McpToolCapabilities>,
    pub resources: Option<McpResourceCapabilities>,
    pub prompts: Option<McpPromptCapabilities>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpToolCapabilities {
    pub list_changed: bool,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpResourceCapabilities {
    pub subscribe: bool,
    pub list_changed: bool,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpPromptCapabilities {
    pub list_changed: bool,
}

/// MCP tool call request
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpToolCallRequest {
    pub name: String,
    pub arguments: HashMap<String, serde_json::Value>,
}

/// MCP tool call response
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpToolCallResponse {
    pub content: Vec<McpContent>,
    pub is_error: bool,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "type", rename_all = "snake_case")]
pub enum McpContent {
    Text { text: String },
    Image { data: String, mime_type: String },
    Resource { resource: McpResourceContent },
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct McpResourceContent {
    pub uri: String,
    pub mime_type: Option<String>,
    pub text: Option<String>,
    pub blob: Option<String>,
}

/// MCP Client trait
#[async_trait]
pub trait McpClient: Send + Sync {
    /// List available tools
    async fn list_tools(&self) -> Result<Vec<McpTool>>;

    /// Call a tool
    async fn call_tool(&self, request: McpToolCallRequest) -> Result<McpToolCallResponse>;

    /// List available resources
    async fn list_resources(&self) -> Result<Vec<McpResource>>;

    /// Read a resource
    async fn read_resource(&self, uri: &str) -> Result<McpResourceContent>;

    /// List available prompts
    async fn list_prompts(&self) -> Result<Vec<McpPrompt>>;

    /// Get a prompt
    async fn get_prompt(&self, name: &str, arguments: HashMap<String, String>) -> Result<String>;
}

/// Basic MCP client implementation
pub struct BasicMcpClient {
    config: McpClientConfig,
    client: reqwest::Client,
}

impl BasicMcpClient {
    pub fn new(config: McpClientConfig) -> Self {
        Self {
            config,
            client: reqwest::Client::new(),
        }
    }
}

#[async_trait]
impl McpClient for BasicMcpClient {
    async fn list_tools(&self) -> Result<Vec<McpTool>> {
        // TODO: Implement actual MCP protocol communication
        Ok(Vec::new())
    }

    async fn call_tool(&self, _request: McpToolCallRequest) -> Result<McpToolCallResponse> {
        // TODO: Implement actual MCP protocol communication
        Ok(McpToolCallResponse {
            content: vec![McpContent::Text { text: "Not implemented".to_string() }],
            is_error: true,
        })
    }

    async fn list_resources(&self) -> Result<Vec<McpResource>> {
        Ok(Vec::new())
    }

    async fn read_resource(&self, _uri: &str) -> Result<McpResourceContent> {
        Ok(McpResourceContent {
            uri: String::new(),
            mime_type: None,
            text: Some("Not implemented".to_string()),
            blob: None,
        })
    }

    async fn list_prompts(&self) -> Result<Vec<McpPrompt>> {
        Ok(Vec::new())
    }

    async fn get_prompt(&self, _name: &str, _arguments: HashMap<String, String>) -> Result<String> {
        Ok("Not implemented".to_string())
    }
}