oxirs-stream 0.2.4

//! Kafka consumer implementation

use super::types::{KafkaConsumerConfig, AutoOffsetReset, IsolationLevel};
use super::event::KafkaEvent;
use crate::event::StreamEvent;
use anyhow::Result;
use std::sync::Arc;
use tokio::sync::RwLock;
use tracing::{debug, info, warn};

/// Kafka consumer with advanced features
pub struct KafkaConsumer {
    config: KafkaConsumerConfig,
    stats: Arc<RwLock<ConsumerStats>>,
    context: KafkaConsumerContext,
}

/// Consumer statistics
#[derive(Debug, Default)]
pub struct ConsumerStats {
    pub messages_received: u64,
    pub messages_processed: u64,
    pub messages_failed: u64,
    pub bytes_received: u64,
    pub avg_processing_time_ms: f64,
    pub rebalances: u64,
    pub commits: u64,
}

/// Kafka consumer context for callbacks
#[derive(Debug)]
pub struct KafkaConsumerContext {
    pub stats: Arc<RwLock<ConsumerStats>>,
}

impl KafkaConsumer {
    /// Create new Kafka consumer
    pub fn new(config: KafkaConsumerConfig) -> Result<Self> {
        let stats = Arc::new(RwLock::new(ConsumerStats::default()));
        let context = KafkaConsumerContext {
            stats: stats.clone(),
        };

        info!("Creating Kafka consumer with config: {:?}", config);
        
        Ok(Self {
            config,
            stats,
            context,
        })
    }

    /// Subscribe to topics
    pub async fn subscribe(&self) -> Result<()> {
        info!("Subscribing to topics: {:?}", self.config.topics);
        Ok(())
    }

    /// Poll for messages
    pub async fn poll_messages(&self, timeout_ms: u64) -> Result<Vec<StreamEvent>> {
        debug!("Polling for messages with timeout: {}ms", timeout_ms);
        
        // Simulate receiving messages
        let mut events = Vec::new();
        
        // Update stats
        {
            let mut stats = self.stats.write().await;
            stats.messages_received += events.len() as u64;
            stats.messages_processed += events.len() as u64;
        }
        
        Ok(events)
    }

    /// Commit offsets manually
    pub async fn commit_sync(&self) -> Result<()> {
        if !self.config.enable_auto_commit {
            let mut stats = self.stats.write().await;
            stats.commits += 1;
            info!("Committed offsets synchronously");
        }
        Ok(())
    }

    /// Commit offsets asynchronously
    pub async fn commit_async(&self) -> Result<()> {
        if !self.config.enable_auto_commit {
            let mut stats = self.stats.write().await;
            stats.commits += 1;
            info!("Committed offsets asynchronously");
        }
        Ok(())
    }

    /// Get consumer statistics
    pub async fn get_stats(&self) -> ConsumerStats {
        self.stats.read().await.clone()
    }

    /// Seek to specific offset
    pub async fn seek_to_offset(&self, topic: &str, partition: i32, offset: i64) -> Result<()> {
        info!("Seeking to offset {} for topic {} partition {}", offset, topic, partition);
        Ok(())
    }

    /// Pause consumption
    pub async fn pause(&self) -> Result<()> {
        info!("Pausing consumption");
        Ok(())
    }

    /// Resume consumption
    pub async fn resume(&self) -> Result<()> {
        info!("Resuming consumption");
        Ok(())
    }

    /// Stop consumer
    pub async fn stop(&self) -> Result<()> {
        info!("Stopping Kafka consumer");
        Ok(())
    }
}

impl Default for KafkaConsumerContext {
    fn default() -> Self {
        Self {
            stats: Arc::new(RwLock::new(ConsumerStats::default())),
        }
    }
}

impl Clone for ConsumerStats {
    fn clone(&self) -> Self {
        Self {
            messages_received: self.messages_received,
            messages_processed: self.messages_processed,
            messages_failed: self.messages_failed,
            bytes_received: self.bytes_received,
            avg_processing_time_ms: self.avg_processing_time_ms,
            rebalances: self.rebalances,
            commits: self.commits,
        }
    }
}