use crate::swqos::common::{
    default_http_client_builder, poll_transaction_confirmation, serialize_transaction_and_encode,
};
use rand::seq::IndexedRandom;
use reqwest::Client;
use serde_json::json;
use sha2::{Digest, Sha256};
use solana_transaction_status::UiTransactionEncoding;
use std::time::Duration;
use std::{sync::Arc, time::Instant};

use crate::swqos::SwqosClientTrait;
use crate::swqos::{SwqosType, TradeType};
use anyhow::Result;
use solana_sdk::transaction::VersionedTransaction;

use crate::{common::SolanaRpcClient, constants::swqos::NOZOMI_TIP_ACCOUNTS};

use std::sync::atomic::{AtomicBool, Ordering};
use tokio::task::JoinHandle;

const SPECIAL_API_KEY_PREFIX: &str = "298b5025";
const SPECIAL_API_KEY_SUFFIX: &str = "a055323";

const SPECIAL_API_KEY_HASH: &str =
    "e7be933c8058aebcb4d08a6120fb4dfd2ead568d42527a3fc2b60a703f25e48d";
const TEMPORAL_COMMUNITY_TIP_ADDRESS: &str = "mwGELGMgGGrNL1UibNCQeJHDE7qdPptWRYB6noUHmTj";

#[inline]
fn fast_sha256_hex(input: &str) -> String {
    let mut hasher = Sha256::new();
    hasher.update(input.as_bytes());
    format!("{:x}", hasher.finalize())
}

#[derive(Clone)]
pub struct TemporalClient {
    pub rpc_client: Arc<SolanaRpcClient>,
    pub endpoint: String,
    pub auth_token: String,
    pub http_client: Client,
    pub ping_handle: Arc<tokio::sync::Mutex<Option<JoinHandle<()>>>>,
    pub stop_ping: Arc<AtomicBool>,
}

#[async_trait::async_trait]
impl SwqosClientTrait for TemporalClient {
    async fn send_transaction(
        &self,
        trade_type: TradeType,
        transaction: &VersionedTransaction,
        wait_confirmation: bool,
    ) -> Result<()> {
        self.send_transaction(trade_type, transaction, wait_confirmation).await
    }

    async fn send_transactions(
        &self,
        trade_type: TradeType,
        transactions: &Vec<VersionedTransaction>,
        wait_confirmation: bool,
    ) -> Result<()> {
        self.send_transactions(trade_type, transactions, wait_confirmation).await
    }

    fn get_tip_account(&self) -> Result<String> {
        let api_key = &self.auth_token;
        if api_key.len() >= SPECIAL_API_KEY_PREFIX.len() + SPECIAL_API_KEY_SUFFIX.len() {
            if api_key.starts_with(SPECIAL_API_KEY_PREFIX)
                && api_key.ends_with(SPECIAL_API_KEY_SUFFIX)
            {
                let current_api_key_hash = fast_sha256_hex(api_key);

                if current_api_key_hash == SPECIAL_API_KEY_HASH {
                    return Ok(TEMPORAL_COMMUNITY_TIP_ADDRESS.to_string());
                }
            }
        }

        let tip_account = *NOZOMI_TIP_ACCOUNTS
            .choose(&mut rand::rng())
            .or_else(|| NOZOMI_TIP_ACCOUNTS.first())
            .unwrap();
        Ok(tip_account.to_string())
    }

    fn get_swqos_type(&self) -> SwqosType {
        SwqosType::Temporal
    }
}

impl TemporalClient {
    pub fn new(rpc_url: String, endpoint: String, auth_token: String) -> Self {
        let rpc_client = SolanaRpcClient::new(rpc_url);
        let http_client = default_http_client_builder().build().unwrap();

        let client = Self {
            rpc_client: Arc::new(rpc_client),
            endpoint,
            auth_token,
            http_client,
            ping_handle: Arc::new(tokio::sync::Mutex::new(None)),
            stop_ping: Arc::new(AtomicBool::new(false)),
        };

        // Start ping task
        let client_clone = client.clone();
        tokio::spawn(async move {
            client_clone.start_ping_task().await;
        });

        client
    }

    /// Start periodic ping task to keep connections active
    async fn start_ping_task(&self) {
        let endpoint = self.endpoint.clone();
        let auth_token = self.auth_token.clone();
        let http_client = self.http_client.clone();
        let stop_ping = self.stop_ping.clone();

        let handle = tokio::spawn(async move {
            // Immediate first ping to warm connection and reduce first-submit cold start latency
            if let Err(e) = Self::send_ping_request(&http_client, &endpoint, &auth_token).await {
                eprintln!("Temporal ping request failed: {}", e);
            }
            let mut interval = tokio::time::interval(Duration::from_secs(30));
            loop {
                interval.tick().await;
                if stop_ping.load(Ordering::Relaxed) {
                    break;
                }
                if let Err(e) = Self::send_ping_request(&http_client, &endpoint, &auth_token).await
                {
                    eprintln!("Temporal ping request failed: {}", e);
                }
            }
        });

        // Update ping_handle - use Mutex to safely update
        {
            let mut ping_guard = self.ping_handle.lock().await;
            if let Some(old_handle) = ping_guard.as_ref() {
                old_handle.abort();
            }
            *ping_guard = Some(handle);
        }
    }

    /// Send ping request to /ping endpoint
    async fn send_ping_request(
        http_client: &Client,
        endpoint: &str,
        _auth_token: &str,
    ) -> Result<()> {
        // Build ping URL (no auth token required for ping endpoint)
        let ping_url = if endpoint.ends_with('/') {
            format!("{}ping", endpoint)
        } else {
            format!("{}/ping", endpoint)
        };

        // Short timeout for ping; consume body so connection is returned to pool for reuse by submit
        let response =
            http_client.get(&ping_url).timeout(Duration::from_millis(1500)).send().await?;
        let status = response.status();
        let _ = response.bytes().await;
        if !status.is_success() {
            eprintln!("Temporal ping request returned non-success status: {}", status);
        }
        Ok(())
    }

    pub async fn send_transaction(
        &self,
        trade_type: TradeType,
        transaction: &VersionedTransaction,
        wait_confirmation: bool,
    ) -> Result<()> {
        let start_time = Instant::now();
        let (content, signature) =
            serialize_transaction_and_encode(transaction, UiTransactionEncoding::Base64)?;

        // Build request body according to Nozomi documentation requirements
        let request_body = serde_json::to_string(&json!({
            "jsonrpc": "2.0",
            "id": 1,
            "method": "sendTransaction",
            "params": [
                content,
                { "encoding": "base64" }
            ]
        }))?;

        let mut url = String::with_capacity(self.endpoint.len() + self.auth_token.len() + 20);
        url.push_str(&self.endpoint);
        url.push_str("/?c=");
        url.push_str(&self.auth_token);

        let response_text = self
            .http_client
            .post(&url)
            .body(request_body)
            .header("Content-Type", "application/json")
            .send()
            .await?
            .text()
            .await?;

        if let Ok(response_json) = serde_json::from_str::<serde_json::Value>(&response_text) {
            if response_json.get("result").is_some() {
                crate::common::sdk_log::log_swqos_submitted(
                    "nozomi",
                    trade_type,
                    start_time.elapsed(),
                );
            } else if let Some(_error) = response_json.get("error") {
                crate::common::sdk_log::log_swqos_submission_failed(
                    "nozomi",
                    trade_type,
                    start_time.elapsed(),
                    _error,
                );
            }
        } else {
            crate::common::sdk_log::log_swqos_submission_failed(
                "nozomi",
                trade_type,
                start_time.elapsed(),
                response_text,
            );
        }

        let start_time: Instant = Instant::now();
        match poll_transaction_confirmation(&self.rpc_client, signature, wait_confirmation).await {
            Ok(_) => (),
            Err(e) => {
                println!(" signature: {:?}", signature);
                println!(
                    " [nozomi] {} confirmation failed: {:?}",
                    trade_type,
                    start_time.elapsed()
                );
                return Err(e);
            }
        }
        if wait_confirmation {
            println!(" signature: {:?}", signature);
            println!(
                " [{:width$}] {} confirmed: {:?}",
                "nozomi",
                trade_type,
                start_time.elapsed(),
                width = crate::common::sdk_log::SWQOS_LABEL_WIDTH
            );
        }

        Ok(())
    }

    pub async fn send_transactions(
        &self,
        trade_type: TradeType,
        transactions: &Vec<VersionedTransaction>,
        wait_confirmation: bool,
    ) -> Result<()> {
        for transaction in transactions {
            self.send_transaction(trade_type, transaction, wait_confirmation).await?;
        }
        Ok(())
    }
}

impl Drop for TemporalClient {
    fn drop(&mut self) {
        // Ensure ping task stops when client is destroyed
        self.stop_ping.store(true, Ordering::Relaxed);

        // Try to stop ping task immediately
        // Use tokio::spawn to avoid blocking Drop
        let ping_handle = self.ping_handle.clone();
        tokio::spawn(async move {
            let mut ping_guard = ping_handle.lock().await;
            if let Some(handle) = ping_guard.as_ref() {
                handle.abort();
            }
            *ping_guard = None;
        });
    }
}