// src/consensus/raft.rs
use super::state::{RaftState, NodeState};
use crate::FutrumError;
use std::sync::Arc;
use tokio::sync::RwLock;
use tokio::time::Duration;
use uuid::Uuid;
use rand;

pub struct RaftConsensus {
    state: Arc<RwLock<RaftState>>,
    node_id: String,
    peers: Vec<String>,
    election_timeout: Duration,
    heartbeat_interval: Duration,
    enabled: bool,
    should_stop: Arc<RwLock<bool>>,
}

impl RaftConsensus {
    pub fn new(enabled: bool, election_timeout_ms: u64, heartbeat_interval_ms: u64) -> Result<Self, FutrumError> {
        let node_id = Uuid::new_v4().to_string();
        
        Ok(Self {
            state: Arc::new(RwLock::new(RaftState::new(node_id.clone()))),
            node_id,
            peers: Vec::new(),
            election_timeout: Duration::from_millis(election_timeout_ms),
            heartbeat_interval: Duration::from_millis(heartbeat_interval_ms),
            enabled,
            should_stop: Arc::new(RwLock::new(false)),
        })
    }
    
    // Тихая версия запуска - БЕЗ ВЫВОДА В КОНСОЛЬ
    pub async fn start_silent(&self) -> Result<(), FutrumError> {
        if !self.enabled {
            return Ok(());
        }

        let state = self.state.clone();
        let node_id = self.node_id.clone();
        let should_stop = self.should_stop.clone();
        let election_timeout = self.election_timeout;
        let heartbeat_interval = self.heartbeat_interval;
        
        tokio::spawn(async move {
            let mut iteration_count = 0;
            
            while !*should_stop.read().await {
                iteration_count += 1;
                
                // ОГРАНИЧИВАЕМ активность - работаем только каждые 100 итераций
                if iteration_count % 100 != 0 {
                    tokio::time::sleep(Duration::from_millis(10)).await;
                    continue;
                }
                
                let current_state = { state.read().await.current_state };
                
                match current_state {
                    NodeState::Follower => {
                        if Self::should_start_election_silent(&should_stop).await && !*should_stop.read().await {
                            state.write().await.current_state = NodeState::Candidate;
                        }
                    }
                    NodeState::Candidate => {
                        if !*should_stop.read().await {
                            let _ = Self::start_election_silent(state.clone()).await;
                        }
                    }
                    NodeState::Leader => {
                        // Минимальная активность в режиме лидера
                    }
                }
                
                tokio::time::sleep(Duration::from_millis(10)).await;
            }
        });
        
        Ok(())
    }
    
    async fn should_start_election_silent(should_stop: &Arc<RwLock<bool>>) -> bool {
        // Увеличиваем таймаут для уменьшения активности
        let timeout = rand::random::<u64>() % 1000 + 500; // 500-1500ms вместо 150-450ms
        tokio::time::sleep(Duration::from_millis(timeout.min(100))).await;
        true
    }
    
    async fn start_election_silent(state: Arc<RwLock<RaftState>>) -> Result<(), FutrumError> {
        let mut state_guard = state.write().await;
        state_guard.current_term += 1;
        state_guard.voted_for = Some(state_guard.node_id.clone());
        state_guard.vote_count = 1;
        
        if state_guard.vote_count > 0 {
            state_guard.current_state = NodeState::Leader;
        }
        
        Ok(())
    }
    
    pub async fn is_leader(&self) -> bool {
        if !self.enabled {
            return false;
        }
        self.state.read().await.current_state == NodeState::Leader
    }
    
    pub async fn get_current_term(&self) -> u64 {
        self.state.read().await.current_term
    }
    
    pub async fn stop(&self) {
        *self.should_stop.write().await = true;
    }
}

impl Clone for RaftConsensus {
    fn clone(&self) -> Self {
        Self {
            state: self.state.clone(),
            node_id: self.node_id.clone(),
            peers: self.peers.clone(),
            election_timeout: self.election_timeout,
            heartbeat_interval: self.heartbeat_interval,
            enabled: self.enabled,
            should_stop: self.should_stop.clone(),
        }
    }
}