use async_trait::async_trait;
use serde::Deserialize;
use serde_json::{json, Value};
use reqwest::Client;

use crate::tools::registry::Tool;
use crate::utils::error::{Result, VTError};
use crate::utils::logger;

/// Search tool for web searches and document retrieval
pub struct Search {
    /// HTTP client for making requests
    client: Client,

    /// API key for search providers (if needed)
    api_key: Option<String>,
}

/// Input parameters for web search
#[derive(Debug, Deserialize)]
pub struct WebSearchParams {
    /// The query to search for
    pub query: String,

    /// Number of results to return (optional)
    pub num_results: Option<usize>,
}

impl Search {
    /// Create a new search tool
    pub fn new(api_key: Option<String>) -> Result<Self> {
        let client = Client::new();

        Ok(Self {
            client,
            api_key,
        })
    }

    /// Perform a web search
    async fn web_search(&self, params: WebSearchParams) -> Result<String> {
        // Since we don't have a real search API here, we'll return a mock response
        // In a real implementation, this would query a search engine API

        logger::info(&format!("Performing web search for: {}", params.query));

        // Number of results to return (default to 3)
        let num_results = params.num_results.unwrap_or(3);

        // Simulate a delay for realism
        tokio::time::sleep(tokio::time::Duration::from_millis(500)).await;

        // Create a mock response
        let results = vec![
            format!("Result 1 for '{}':\nA mock search result that might be relevant to your query.", params.query),
            format!("Result 2 for '{}':\nAnother mock search result with potentially useful information.", params.query),
            format!("Result 3 for '{}':\nA third mock search result that could contain what you're looking for.", params.query),
            format!("Result 4 for '{}':\nYet another mock search result with additional details.", params.query),
            format!("Result 5 for '{}':\nOne more mock search result to round out the set.", params.query),
        ];

        // Return the requested number of results
        let limited_results = results.into_iter().take(num_results).collect::<Vec<_>>();

        Ok(limited_results.join("\n\n"))
    }

    /// Search in documents (for RAG implementation)
    async fn document_search(&self, query: &str, collection: &str) -> Result<String> {
        // This would typically use a vector database like Milvus, Pinecone, etc.
        // For now, we'll return a mock response

        logger::info(&format!("Searching documents in collection '{}' for: {}", collection, query));

        // Simulate a delay for realism
        tokio::time::sleep(tokio::time::Duration::from_millis(300)).await;

        Ok(format!("Mock document search results for '{}' in collection '{}':\n\nDocument 1: Contains information relevant to your query.\nDocument 2: Additional context that might help answer your question.", query, collection))
    }

    /// Basic async web search function
    pub async fn search_web(query: &str) -> crate::utils::error::Result<String> {
        // Placeholder: In production, integrate with a real search API
        Ok(format!("Search results for: {}", query))
    }
}

#[async_trait]
impl Tool for Search {
    fn name(&self) -> &str {
        "search"
    }

    fn description(&self) -> &str {
        "Searches the web or documents for information"
    }

    fn parameters_schema(&self) -> Value {
        json!({
            "type": "object",
            "properties": {
                "search_type": {
                    "type": "string",
                    "description": "The type of search to perform (web or document)",
                    "enum": ["web", "document"]
                },
                "query": {
                    "type": "string",
                    "description": "The search query"
                },
                "num_results": {
                    "type": "integer",
                    "description": "Number of results to return (for web search)",
                    "minimum": 1,
                    "maximum": 10
                },
                "collection": {
                    "type": "string",
                    "description": "Document collection to search in (for document search)"
                }
            },
            "required": ["search_type", "query"],
            "allOf": [
                {
                    "if": {
                        "properties": { "search_type": { "const": "document" } }
                    },
                    "then": {
                        "required": ["collection"]
                    }
                }
            ]
        })
    }

    async fn execute(&self, args: Value) -> Result<String> {
        // Get the search type
        let search_type = args.get("search_type")
            .and_then(|v| v.as_str())
            .ok_or_else(|| VTError::InvalidRequest("Missing search_type parameter".to_string()))?;

        // Get the query
        let query = args.get("query")
            .and_then(|v| v.as_str())
            .ok_or_else(|| VTError::InvalidRequest("Missing query parameter".to_string()))?;

        // Execute the appropriate search
        match search_type {
            "web" => {
                let num_results = args.get("num_results")
                    .and_then(|v| v.as_u64())
                    .map(|v| v as usize);

                let params = WebSearchParams {
                    query: query.to_string(),
                    num_results,
                };

                self.web_search(params).await
            },
            "document" => {
                let collection = args.get("collection")
                    .and_then(|v| v.as_str())
                    .ok_or_else(|| VTError::InvalidRequest("Missing collection parameter for document search".to_string()))?;

                self.document_search(query, collection).await
            },
            _ => Err(VTError::InvalidRequest(format!("Unsupported search type: {}", search_type))),
        }
    }
}