// src/corporate/update.rs - UPDATED WITH DATA INTEGRITY FIXES
use super::{scraper::*, storage::*, helpers::*, types::*, openfigi::*, yahoo::*};
use crate::config::Config;
use crate::corporate::update_parallel::build_companies_jsonl_streaming_parallel;
use crate::util::directories::DataPaths;
use crate::util::logger;
use crate::scraper::webdriver::ChromeDriverPool;

use chrono::Local;
use std::collections::HashMap;
use std::sync::Arc;
use std::sync::atomic::{AtomicBool, Ordering};

/// UPDATED: Main corporate update entry point with shutdown awareness
pub async fn run_full_update(
    _config: &Config, 
    pool: &Arc<ChromeDriverPool>,
    shutdown_flag: &Arc<AtomicBool>,
) -> anyhow::Result<()> {
    logger::log_info("=== Corporate Update (STREAMING MODE WITH DATA INTEGRITY) ===").await;

    let paths = DataPaths::new(".")?;

    logger::log_info("Step 1: Downloading GLEIF CSV...").await;
    let gleif_csv_path = match download_isin_lei_csv().await? {
        Some(p) => {
            logger::log_info(&format!("  ✓ GLEIF CSV at: {}", p)).await;
            p
        }
        None => {
            logger::log_warn("  ✗ Could not obtain GLEIF CSV").await;
            return Ok(());
        }
    };

    if shutdown_flag.load(Ordering::SeqCst) {
        logger::log_warn("Shutdown detected after GLEIF download").await;
        return Ok(());
    }

    logger::log_info("Step 2: Loading OpenFIGI metadata...").await;
    load_figi_type_lists().await.ok();
    logger::log_info("  ✓ OpenFIGI metadata loaded").await;

    if shutdown_flag.load(Ordering::SeqCst) {
        logger::log_warn("Shutdown detected after OpenFIGI load").await;
        return Ok(());
    }

    logger::log_info("Step 3: Checking LEI-FIGI mapping status...").await;
    let all_mapped = ensure_all_leis_mapped(&gleif_csv_path, None).await?;
    
    if !all_mapped {
        logger::log_warn("  ⚠ Some LEIs failed to map - continuing with partial data").await;
    } else {
        logger::log_info("  ✓ All LEIs successfully mapped").await;
    }

    if shutdown_flag.load(Ordering::SeqCst) {
        logger::log_warn("Shutdown detected after LEI-FIGI mapping").await;
        return Ok(());
    }

    logger::log_info("Step 4: Building securities map (streaming)...").await;
    let date_dir = find_most_recent_figi_date_dir(&paths).await?;
    
    if let Some(date_dir) = date_dir {
        logger::log_info(&format!("  Using FIGI data from: {:?}", date_dir)).await;
        build_securities_from_figi_streaming(&date_dir).await?;
        logger::log_info("  ✓ Securities map updated").await;
    } else {
        logger::log_warn("  ✗ No FIGI data directory found").await;
    }

    if shutdown_flag.load(Ordering::SeqCst) {
        logger::log_warn("Shutdown detected after securities map build").await;
        return Ok(());
    }

    logger::log_info("Step 5: Building companies.jsonl with parallel processing and validation...").await;
    let count = build_companies_jsonl_streaming_parallel(&paths, pool, shutdown_flag).await?;
    logger::log_info(&format!("  ✓ Saved {} companies", count)).await;

    if !shutdown_flag.load(Ordering::SeqCst) {
        logger::log_info("Step 6: Processing events (using index)...").await;
        let _event_index = build_event_index(&paths).await?;
        logger::log_info("  ✓ Event index built").await;
    } else {
        logger::log_warn("Shutdown detected, skipping event index build").await;
    }

    logger::log_info("✓ Corporate update complete").await;
    Ok(())
}

/// UPDATED: Serial version with validation (kept for compatibility/debugging)
/// 
/// This is the non-parallel version that processes companies sequentially.
/// Updated with same validation and shutdown checks as parallel version.
/// 
/// Use this for:
/// - Debugging issues with specific companies
/// - Environments where parallel processing isn't desired
/// - Testing validation logic without concurrency complexity
async fn build_companies_jsonl_streaming_serial(
    paths: &DataPaths, 
    pool: &Arc<ChromeDriverPool>,
    shutdown_flag: &Arc<AtomicBool>,
) -> anyhow::Result<usize> {
    // Configuration constants
    const CHECKPOINT_INTERVAL: usize = 50;
    const FSYNC_BATCH_SIZE: usize = 10;
    const FSYNC_INTERVAL_SECS: u64 = 10;
    
    let path = DataPaths::new(".")?;
    let corporate_path = path.data_dir().join("corporate").join("by_name");
    let securities_path = corporate_path.join("common_stocks.json");
    
    if !securities_path.exists() {
        logger::log_warn("No common_stocks.json found").await;
        return Ok(0);
    }
    
    let content = tokio::fs::read_to_string(securities_path).await?;
    let securities: HashMap<String, CompanyInfo> = serde_json::from_str(&content)?;
    
    let companies_path = paths.data_dir().join("companies.jsonl");
    let log_path = paths.data_dir().join("companies_updates.log");
    
    if let Some(parent) = companies_path.parent() {
        tokio::fs::create_dir_all(parent).await?;
    }
    
    // === RECOVERY PHASE: Load checkpoint + replay log ===
    let mut existing_companies: HashMap<String, CompanyCrossPlatformInfo> = HashMap::new();
    let mut processed_names: std::collections::HashSet<String> = std::collections::HashSet::new();
    
    if companies_path.exists() {
        logger::log_info("Loading checkpoint from companies.jsonl...").await;
        let existing_content = tokio::fs::read_to_string(&companies_path).await?;
        
        for line in existing_content.lines() {
            if line.trim().is_empty() {
                continue;
            }
            
            match serde_json::from_str::<CompanyCrossPlatformInfo>(line) {
                Ok(company) => {
                    processed_names.insert(company.name.clone());
                    existing_companies.insert(company.name.clone(), company);
                }
                Err(e) => {
                    logger::log_warn(&format!("Skipping invalid checkpoint line: {}", e)).await;
                }
            }
        }
        logger::log_info(&format!("Loaded checkpoint with {} companies", existing_companies.len())).await;
    }
    
    if log_path.exists() {
        logger::log_info("Replaying update log...").await;
        let log_content = tokio::fs::read_to_string(&log_path).await?;
        let mut replayed = 0;
        
        for line in log_content.lines() {
            if line.trim().is_empty() {
                continue;
            }
            
            match serde_json::from_str::<CompanyCrossPlatformInfo>(line) {
                Ok(company) => {
                    processed_names.insert(company.name.clone());
                    existing_companies.insert(company.name.clone(), company);
                    replayed += 1;
                }
                Err(e) => {
                    logger::log_warn(&format!("Skipping invalid log line: {}", e)).await;
                }
            }
        }
        if replayed > 0 {
            logger::log_info(&format!("Replayed {} updates from log", replayed)).await;
        }
    }
    
    // === OPEN LOG FILE ===
    use tokio::fs::OpenOptions;
    use tokio::io::AsyncWriteExt;
    
    let mut log_file = OpenOptions::new()
        .create(true)
        .append(true)
        .open(&log_path)
        .await?;
    
    let mut writes_since_fsync = 0;
    let mut last_fsync = std::time::Instant::now();
    let mut updates_since_checkpoint = 0;
    let mut count = 0;
    let mut new_count = 0;
    let mut updated_count = 0;
    
    logger::log_info(&format!("Processing {} companies sequentially...", securities.len())).await;
    
    // === PROCESS COMPANIES SEQUENTIALLY ===
    for (name, company_info) in securities.clone() {
        // Check shutdown before each company
        if shutdown_flag.load(Ordering::SeqCst) {
            logger::log_warn(&format!(
                "Shutdown detected at company: {} (progress: {}/{})",
                name, count, count + securities.len()
            )).await;
            break;
        }
        
        let existing_entry = existing_companies.get(&name).cloned();
        let is_update = existing_entry.is_some();
        
        // Process company with validation
        match process_single_company_serial(
            name.clone(),
            company_info,
            existing_entry,
            pool,
            shutdown_flag,
        ).await {
            Ok(Some(company_entry)) => {
                // Write to log
                let line = serde_json::to_string(&company_entry)?;
                log_file.write_all(line.as_bytes()).await?;
                log_file.write_all(b"\n").await?;
                
                writes_since_fsync += 1;
                
                // Batched + time-based fsync
                let should_fsync = writes_since_fsync >= FSYNC_BATCH_SIZE 
                    || last_fsync.elapsed().as_secs() >= FSYNC_INTERVAL_SECS;
                
                if should_fsync {
                    log_file.flush().await?;
                    log_file.sync_data().await?;
                    writes_since_fsync = 0;
                    last_fsync = std::time::Instant::now();
                }
                
                // Update in-memory state
                processed_names.insert(name.clone());
                existing_companies.insert(name.clone(), company_entry);
                
                count += 1;
                updates_since_checkpoint += 1;
                
                if is_update {
                    updated_count += 1;
                } else {
                    new_count += 1;
                }
                
                // Periodic checkpoint
                if updates_since_checkpoint >= CHECKPOINT_INTERVAL {
                    if writes_since_fsync > 0 {
                        log_file.flush().await?;
                        log_file.sync_data().await?;
                        writes_since_fsync = 0;
                        last_fsync = std::time::Instant::now();
                    }
                    
                    logger::log_info(&format!("Creating checkpoint at {} companies...", count)).await;
                    
                    let checkpoint_tmp = companies_path.with_extension("jsonl.tmp");
                    let mut checkpoint_file = tokio::fs::File::create(&checkpoint_tmp).await?;
                    
                    for company in existing_companies.values() {
                        let line = serde_json::to_string(company)?;
                        checkpoint_file.write_all(line.as_bytes()).await?;
                        checkpoint_file.write_all(b"\n").await?;
                    }
                    
                    checkpoint_file.flush().await?;
                    checkpoint_file.sync_all().await?;
                    drop(checkpoint_file);
                    
                    tokio::fs::rename(&checkpoint_tmp, &companies_path).await?;
                    
                    drop(log_file);
                    tokio::fs::remove_file(&log_path).await.ok();
                    log_file = OpenOptions::new()
                        .create(true)
                        .append(true)
                        .open(&log_path)
                        .await?;
                    
                    updates_since_checkpoint = 0;
                    logger::log_info("✓ Checkpoint created and log cleared").await;
                }
                
                if count % 10 == 0 {
                    logger::log_info(&format!(
                        "Progress: {} companies ({} new, {} updated)",
                        count, new_count, updated_count
                    )).await;
                }
            }
            Ok(None) => {
                // Company had no ISINs or was skipped
                logger::log_info(&format!("Skipped company: {} (no ISINs)", name)).await;
            }
            Err(e) => {
                logger::log_warn(&format!("Error processing company {}: {}", name, e)).await;
            }
        }
        
        // Time-based fsync
        if writes_since_fsync > 0 && last_fsync.elapsed().as_secs() >= FSYNC_INTERVAL_SECS {
            log_file.flush().await?;
            log_file.sync_data().await?;
            writes_since_fsync = 0;
            last_fsync = std::time::Instant::now();
        }
    }
    
    // === FSYNC PENDING WRITES ===
    if writes_since_fsync > 0 {
        logger::log_info(&format!("Fsyncing {} pending writes...", writes_since_fsync)).await;
        log_file.flush().await?;
        log_file.sync_data().await?;
        logger::log_info("✓ Pending writes saved").await;
    }
    
    // === FINAL CHECKPOINT ===
    if !shutdown_flag.load(Ordering::SeqCst) && updates_since_checkpoint > 0 {
        logger::log_info("Creating final checkpoint...").await;
        
        let checkpoint_tmp = companies_path.with_extension("jsonl.tmp");
        let mut checkpoint_file = tokio::fs::File::create(&checkpoint_tmp).await?;
        
        for company in existing_companies.values() {
            let line = serde_json::to_string(company)?;
            checkpoint_file.write_all(line.as_bytes()).await?;
            checkpoint_file.write_all(b"\n").await?;
        }
        
        checkpoint_file.flush().await?;
        checkpoint_file.sync_all().await?;
        drop(checkpoint_file);
        
        tokio::fs::rename(&checkpoint_tmp, &companies_path).await?;
        
        drop(log_file);
        tokio::fs::remove_file(&log_path).await.ok();
        
        logger::log_info("✓ Final checkpoint created").await;
    }
    
    logger::log_info(&format!(
        "Completed: {} total companies ({} new, {} updated)",
        count, new_count, updated_count
    )).await;
    
    Ok(count)
}

/// UPDATED: Process single company serially with validation
async fn process_single_company_serial(
    name: String,
    company_info: CompanyInfo,
    existing_entry: Option<CompanyCrossPlatformInfo>,
    pool: &Arc<ChromeDriverPool>,
    shutdown_flag: &Arc<AtomicBool>,
) -> anyhow::Result<Option<CompanyCrossPlatformInfo>> {
    // Check shutdown at start
    if shutdown_flag.load(Ordering::SeqCst) {
        return Ok(None);
    }
    
    let mut isin_tickers_map: HashMap<String, Vec<String>> = 
        existing_entry
            .as_ref()
            .map(|e| e.isin_tickers_map.clone())
            .unwrap_or_default();
    
    let mut sector = existing_entry.as_ref().and_then(|e| e.sector.clone());
    let mut exchange = existing_entry.as_ref().and_then(|e| e.exchange.clone());
    
    // Collect unique ISIN-ticker pairs
    let mut unique_isin_ticker_pairs: HashMap<String, Vec<String>> = HashMap::new();
    
    for figi_infos in company_info.securities.values() {
        for figi_info in figi_infos {
            if !figi_info.isin.is_empty() {
                let tickers = unique_isin_ticker_pairs
                    .entry(figi_info.isin.clone())
                    .or_insert_with(Vec::new);
                
                if !figi_info.ticker.is_empty() && !tickers.contains(&figi_info.ticker) {
                    tickers.push(figi_info.ticker.clone());
                }
            }
        }
    }
    
    // Process each ISIN with validation
    for (isin, figi_tickers) in unique_isin_ticker_pairs {
        // Check shutdown before each ISIN
        if shutdown_flag.load(Ordering::SeqCst) {
            return Ok(None);
        }

        let tickers = isin_tickers_map
            .entry(isin.clone())
            .or_insert_with(Vec::new);
        
        for figi_ticker in figi_tickers {
            if !tickers.contains(&figi_ticker) {
                tickers.push(figi_ticker);
            }
        }
        
        let has_yahoo_ticker = tickers.iter().any(|t| t.starts_with("YAHOO:"));
        
        if !has_yahoo_ticker {
            logger::log_info(&format!("Fetching Yahoo details for {} (ISIN: {})", name, isin)).await;
            
            // Use validated scraping with retry
            match scrape_with_retry_serial(pool, &isin, 3, shutdown_flag).await {
                Ok(Some(details)) => {
                    logger::log_info(&format!(
                        "✓ Found Yahoo ticker {} for ISIN {} (company: {})",
                        details.ticker, isin, name
                    )).await;
                    
                    tickers.push(format!("YAHOO:{}", details.ticker));
                    
                    if sector.is_none() && details.sector.is_some() {
                        sector = details.sector.clone();
                    }
                    
                    if exchange.is_none() && details.exchange.is_some() {
                        exchange = details.exchange.clone();
                    }
                },
                Ok(None) => {
                    logger::log_warn(&format!("◯ No search results for ISIN {} (company: {})", isin, name)).await;
                    tickers.push("YAHOO:NO_RESULTS".to_string());
                },
                Err(e) => {
                    if shutdown_flag.load(Ordering::SeqCst) {
                        return Ok(None);
                    }
                    logger::log_warn(&format!(
                        "✗ Yahoo lookup error for ISIN {} (company: {}): {}",
                        isin, name, e
                    )).await;
                }
            }
        }
    }
    
    // Final shutdown check
    if shutdown_flag.load(Ordering::SeqCst) {
        return Ok(None);
    }

    if !isin_tickers_map.is_empty() {
        Ok(Some(CompanyCrossPlatformInfo {
            name,
            isin_tickers_map,
            sector,
            exchange,
        }))
    } else {
        Ok(None)
    }
}

/// UPDATED: Scrape with retry for serial processing
async fn scrape_with_retry_serial(
    pool: &Arc<ChromeDriverPool>,
    isin: &str,
    max_retries: u32,
    shutdown_flag: &Arc<AtomicBool>,
) -> anyhow::Result<Option<YahooCompanyDetails>> {
    let mut retries = 0;
    
    loop {
        if shutdown_flag.load(Ordering::SeqCst) {
            return Err(anyhow::anyhow!("Aborted due to shutdown"));
        }
        
        match scrape_company_details_by_isin(pool, isin, shutdown_flag).await {
            Ok(result) => return Ok(result),
            Err(e) => {
                if retries >= max_retries {
                    return Err(e);
                }
                
                let backoff_ms = 1000 * 2u64.pow(retries);
                let jitter_ms = random_range(0, 500);
                let total_delay = backoff_ms + jitter_ms;
                
                logger::log_warn(&format!(
                    "Retry {}/{} for ISIN {} after {}ms: {}",
                    retries + 1, max_retries, isin, total_delay, e
                )).await;
                
                tokio::time::sleep(tokio::time::Duration::from_millis(total_delay)).await;
                retries += 1;
            }
        }
    }
}

async fn find_most_recent_figi_date_dir(paths: &DataPaths) -> anyhow::Result<Option<std::path::PathBuf>> {
    let map_cache_dir = paths.cache_gleif_openfigi_map_dir();
    
    if !map_cache_dir.exists() {
        return Ok(None);
    }
    
    let mut entries = tokio::fs::read_dir(&map_cache_dir).await?;
    let mut dates = Vec::new();
    
    while let Some(entry) = entries.next_entry().await? {
        let path = entry.path();
        if path.is_dir() {
            if let Some(name) = path.file_name().and_then(|n| n.to_str()) {
                if name.len() == 8 && name.chars().all(|c| c.is_numeric()) {
                    dates.push((name.to_string(), path));
                }
            }
        }
    }
    
    if dates.is_empty() {
        return Ok(None);
    }
    
    dates.sort_by(|a, b| b.0.cmp(&a.0));
    Ok(Some(dates[0].1.clone()))
}

pub struct ProcessResult {
    pub changes: Vec<CompanyEventChange>,
}

pub fn process_batch(
    new_events: &[CompanyEvent],
    existing: &mut HashMap<String, CompanyEvent>,
    today: &str,
) -> ProcessResult {
    let mut changes = Vec::new();

    for new in new_events {
        let key = event_key(new);

        if let Some(old) = existing.get(&key) {
            changes.extend(detect_changes(old, new, today));
            existing.insert(key, new.clone());
            continue;
        }

        let date_key = format!("{}|{}", new.ticker, new.date);
        let mut found_old = None;
        for (k, e) in existing.iter() {
            if format!("{}|{}", e.ticker, e.date) == date_key && k != &key {
                found_old = Some((k.clone(), e.clone()));
                break;
            }
        }

        if let Some((old_key, old_event)) = found_old {
            if new.date.as_str() > today {
                changes.push(CompanyEventChange {
                    ticker: new.ticker.clone(),
                    date: new.date.clone(),
                    field_changed: "time".to_string(),
                    old_value: old_event.time.clone(),
                    new_value: new.time.clone(),
                    detected_at: Local::now().format("%Y-%m-%d %H:%M:%S").to_string(),
                });
            }
            existing.remove(&old_key);
        }

        existing.insert(key, new.clone());
    }

    ProcessResult { changes }
}