import pLimit from 'p-limit';
import { createCache, type CacheProvider } from '@stock-bot/cache';
import { HttpClient, ProxyInfo } from '@stock-bot/http';
import { getLogger } from '@stock-bot/logger';

// Type definitions
export interface ProxySource {
  id: string;
  url: string;
  protocol: string;
  working?: number; // Optional, used for stats
  total?: number; // Optional, used for stats
  percentWorking?: number; // Optional, used for stats
  lastChecked?: Date; // Optional, used for stats
}

// Shared configuration and utilities
const PROXY_CONFIG = {
  CACHE_KEY: 'active',
  CACHE_STATS_KEY: 'stats',
  CACHE_TTL: 86400, // 24 hours
  CHECK_TIMEOUT: 7000,
  CHECK_IP: '99.246.102.205',
  CHECK_URL: 'https://proxy-detection.stare.gg/?api_key=bd406bf53ddc6abe1d9de5907830a955',
  CONCURRENCY_LIMIT: 100,
  PROXY_SOURCES: [
    {
      id: 'prxchk',
      url: 'https://raw.githubusercontent.com/prxchk/proxy-list/main/http.txt',
      protocol: 'http',
    },
    {
      id: 'casals',
      url: 'https://raw.githubusercontent.com/casals-ar/proxy-list/main/http',
      protocol: 'http',
    },
    {
      id: 'sunny9577',
      url: 'https://raw.githubusercontent.com/sunny9577/proxy-scraper/master/proxies.txt',
      protocol: 'http',
    },
    {
      id: 'themiralay',
      url: 'https://raw.githubusercontent.com/themiralay/Proxy-List-World/refs/heads/master/data.txt',
      protocol: 'http',
    },
    {
      id: 'casa-ls',
      url: 'https://raw.githubusercontent.com/casa-ls/proxy-list/refs/heads/main/http',
      protocol: 'http',
    },
    {
      id: 'databay',
      url: 'https://raw.githubusercontent.com/databay-labs/free-proxy-list/refs/heads/master/http.txt',
      protocol: 'http',
    },
    {
      id: 'speedx',
      url: 'https://raw.githubusercontent.com/TheSpeedX/PROXY-List/master/http.txt',
      protocol: 'http',
    },
    {
      id: 'monosans',
      url: 'https://raw.githubusercontent.com/monosans/proxy-list/main/proxies/http.txt',
      protocol: 'http',
    },

    {
      id: 'murong',
      url: 'https://raw.githubusercontent.com/MuRongPIG/Proxy-Master/main/http.txt',
      protocol: 'http',
    },
    {
      id: 'vakhov-fresh',
      url: 'https://raw.githubusercontent.com/vakhov/fresh-proxy-list/master/http.txt',
      protocol: 'http',
    },
    {
      id: 'kangproxy',
      url: 'https://raw.githubusercontent.com/officialputuid/KangProxy/refs/heads/KangProxy/http/http.txt',
      protocol: 'http',
    },
    {
      id: 'gfpcom',
      url: 'https://raw.githubusercontent.com/gfpcom/free-proxy-list/refs/heads/main/list/http.txt',
      protocol: 'http',
    },
    {
      id: 'dpangestuw',
      url: 'https://raw.githubusercontent.com/dpangestuw/Free-Proxy/refs/heads/main/http_proxies.txt',
      protocol: 'http',
    },
    {
      id: 'gitrecon',
      url: 'https://raw.githubusercontent.com/gitrecon1455/fresh-proxy-list/refs/heads/main/proxylist.txt',
      protocol: 'http',
    },
    {
      id: 'vakhov-master',
      url: 'https://raw.githubusercontent.com/vakhov/fresh-proxy-list/refs/heads/master/http.txt',
      protocol: 'http',
    },
    {
      id: 'breaking-tech',
      url: 'https://raw.githubusercontent.com/BreakingTechFr/Proxy_Free/refs/heads/main/proxies/http.txt',
      protocol: 'http',
    },
    {
      id: 'ercindedeoglu',
      url: 'https://raw.githubusercontent.com/ErcinDedeoglu/proxies/main/proxies/http.txt',
      protocol: 'http',
    },
    {
      id: 'tuanminpay',
      url: 'https://raw.githubusercontent.com/TuanMinPay/live-proxy/master/http.txt',
      protocol: 'http',
    },

    {
      id: 'r00tee-https',
      url: 'https://raw.githubusercontent.com/r00tee/Proxy-List/refs/heads/main/Https.txt',
      protocol: 'https',
    },
    {
      id: 'ercindedeoglu-https',
      url: 'https://raw.githubusercontent.com/ErcinDedeoglu/proxies/main/proxies/https.txt',
      protocol: 'https',
    },
    {
      id: 'vakhov-fresh-https',
      url: 'https://raw.githubusercontent.com/vakhov/fresh-proxy-list/refs/heads/master/https.txt',
      protocol: 'https',
    },
    {
      id: 'databay-https',
      url: 'https://raw.githubusercontent.com/databay-labs/free-proxy-list/refs/heads/master/https.txt',
      protocol: 'https',
    },
    {
      id: 'kangproxy-https',
      url: 'https://raw.githubusercontent.com/officialputuid/KangProxy/refs/heads/KangProxy/https/https.txt',
      protocol: 'https',
    },
    {
      id: 'zloi-user-https',
      url: 'https://raw.githubusercontent.com/zloi-user/hideip.me/refs/heads/master/https.txt',
      protocol: 'https',
    },
    {
      id: 'gfpcom-https',
      url: 'https://raw.githubusercontent.com/gfpcom/free-proxy-list/refs/heads/main/list/https.txt',
      protocol: 'https',
    },
  ],
};

// Shared instances (module-scoped, not global)
let logger: ReturnType<typeof getLogger>;
let cache: CacheProvider;
let httpClient: HttpClient;
let concurrencyLimit: ReturnType<typeof pLimit>;
let proxyStats: ProxySource[] = PROXY_CONFIG.PROXY_SOURCES.map(source => ({
  id: source.id,
  total: 0,
  working: 0,
  lastChecked: new Date(),
  protocol: source.protocol,
  url: source.url,
}));

// make a function that takes in source id and a boolean success and updates the proxyStats array
async function updateProxyStats(sourceId: string, success: boolean) {
  const source = proxyStats.find(s => s.id === sourceId);
  if (source !== undefined) {
    if (typeof source.working !== 'number') source.working = 0;
    if (typeof source.total !== 'number') source.total = 0;
    source.total += 1;
    if (success) {
      source.working += 1;
    }
    source.percentWorking = (source.working / source.total) * 100;
    source.lastChecked = new Date();
    await cache.set(`${PROXY_CONFIG.CACHE_STATS_KEY}:${source.id}`, source, PROXY_CONFIG.CACHE_TTL);
    return source;
  } else {
    logger.warn(`Unknown proxy source: ${sourceId}`);
  }
}

// make a function that resets proxyStats
async function resetProxyStats(): Promise<void> {
  proxyStats = PROXY_CONFIG.PROXY_SOURCES.map(source => ({
    id: source.id,
    total: 0,
    working: 0,
    lastChecked: new Date(),
    protocol: source.protocol,
    url: source.url,
  }));
  for (const source of proxyStats) {
    await cache.set(`${PROXY_CONFIG.CACHE_STATS_KEY}:${source.id}`, source, PROXY_CONFIG.CACHE_TTL);
  }
  return Promise.resolve();
}

/**
 * Update proxy data in cache with working/total stats and average response time
 * @param proxy - The proxy to update
 * @param isWorking - Whether the proxy is currently working
 */
async function updateProxyInCache(proxy: ProxyInfo, isWorking: boolean): Promise<void> {
  const cacheKey = `${PROXY_CONFIG.CACHE_KEY}:${proxy.protocol}://${proxy.host}:${proxy.port}`;

  try {
    const existing: any = await cache.get(cacheKey);

    // For failed proxies, only update if they already exist
    if (!isWorking && !existing) {
      logger.debug('Proxy not in cache, skipping failed update', {
        proxy: `${proxy.host}:${proxy.port}`,
      });
      return;
    }

    // Calculate new average response time if we have a response time
    let newAverageResponseTime = existing?.averageResponseTime;
    if (proxy.responseTime !== undefined) {
      const existingAvg = existing?.averageResponseTime || 0;
      const existingTotal = existing?.total || 0;

      // Calculate weighted average: (existing_avg * existing_count + new_response) / (existing_count + 1)
      newAverageResponseTime =
        existingTotal > 0
          ? (existingAvg * existingTotal + proxy.responseTime) / (existingTotal + 1)
          : proxy.responseTime;
    }

    // Build updated proxy data
    const updated = {
      ...existing,
      ...proxy, // Keep latest proxy info
      total: (existing?.total || 0) + 1,
      working: isWorking ? (existing?.working || 0) + 1 : existing?.working || 0,
      isWorking,
      lastChecked: new Date(),
      // Add firstSeen only for new entries
      ...(existing ? {} : { firstSeen: new Date() }),
      // Update average response time if we calculated a new one
      ...(newAverageResponseTime !== undefined
        ? { averageResponseTime: newAverageResponseTime }
        : {}),
    };

    // Calculate success rate
    updated.successRate = updated.total > 0 ? (updated.working / updated.total) * 100 : 0;

    // Save to cache: reset TTL for working proxies, keep existing TTL for failed ones
    const cacheOptions = isWorking ? PROXY_CONFIG.CACHE_TTL : undefined;
    await cache.set(cacheKey, updated, cacheOptions);

    logger.debug(`Updated ${isWorking ? 'working' : 'failed'} proxy in cache`, {
      proxy: `${proxy.host}:${proxy.port}`,
      working: updated.working,
      total: updated.total,
      successRate: updated.successRate.toFixed(1) + '%',
      avgResponseTime: updated.averageResponseTime
        ? `${updated.averageResponseTime.toFixed(0)}ms`
        : 'N/A',
    });
  } catch (error) {
    logger.error('Failed to update proxy in cache', {
      proxy: `${proxy.host}:${proxy.port}`,
      error: error instanceof Error ? error.message : String(error),
    });
  }
}

/**
 * Initialize proxy cache for use during application startup
 * This should be called before any proxy operations
 */
export async function initializeProxyCache(): Promise<void> {
  logger = getLogger('proxy-tasks');
  cache = createCache({
    keyPrefix: 'proxy:',
    ttl: PROXY_CONFIG.CACHE_TTL,
    enableMetrics: true,
  });

  logger.info('Initializing proxy cache...');
  await cache.waitForReady(10000);
  logger.info('Proxy cache initialized successfully');

  // Initialize other shared resources that don't require cache
  httpClient = new HttpClient({ timeout: 10000 }, logger);
  concurrencyLimit = pLimit(PROXY_CONFIG.CONCURRENCY_LIMIT);

  logger.info('Proxy tasks initialized');
}

async function initializeSharedResources() {
  if (!logger) {
    // If not initialized at startup, initialize with fallback mode
    logger = getLogger('proxy-tasks');
    cache = createCache({
      keyPrefix: 'proxy:',
      ttl: PROXY_CONFIG.CACHE_TTL,
      enableMetrics: true,
    });

    httpClient = new HttpClient({ timeout: 10000 }, logger);
    concurrencyLimit = pLimit(PROXY_CONFIG.CONCURRENCY_LIMIT);

    logger.info('Proxy tasks initialized (fallback mode)');
  }
}

// Individual task functions
export async function queueProxyFetch(): Promise<string> {
  await initializeSharedResources();

  const { queueManager } = await import('../services/queue.service');
  const job = await queueManager.addJob({
    type: 'proxy-fetch',
    provider: 'proxy-service',
    operation: 'fetch-and-check',
    payload: {},
    priority: 5,
  });

  const jobId = job.id || 'unknown';
  logger.info('Proxy fetch job queued', { jobId });
  return jobId;
}

export async function queueProxyCheck(proxies: ProxyInfo[]): Promise<string> {
  await initializeSharedResources();

  const { queueManager } = await import('../services/queue.service');
  const job = await queueManager.addJob({
    type: 'proxy-check',
    provider: 'proxy-service',
    operation: 'check-specific',
    payload: { proxies },
    priority: 3,
  });

  const jobId = job.id || 'unknown';
  logger.info('Proxy check job queued', { jobId, count: proxies.length });
  return jobId;
}

export async function fetchProxiesFromSources(): Promise<ProxyInfo[]> {
  await initializeSharedResources();
  await resetProxyStats();

  // Ensure concurrencyLimit is available before using it
  if (!concurrencyLimit) {
    logger.error('concurrencyLimit not initialized, using sequential processing');
    const result = [];
    for (const source of PROXY_CONFIG.PROXY_SOURCES) {
      const proxies = await fetchProxiesFromSource(source);
      result.push(...proxies);
    }
    let allProxies: ProxyInfo[] = result;
    allProxies = removeDuplicateProxies(allProxies);
    return allProxies;
  }

  const sources = PROXY_CONFIG.PROXY_SOURCES.map(source =>
    concurrencyLimit(() => fetchProxiesFromSource(source))
  );
  const result = await Promise.all(sources);
  let allProxies: ProxyInfo[] = result.flat();
  allProxies = removeDuplicateProxies(allProxies);
  // await checkProxies(allProxies);
  return allProxies;
}

export async function fetchProxiesFromSource(source: ProxySource): Promise<ProxyInfo[]> {
  await initializeSharedResources();

  const allProxies: ProxyInfo[] = [];

  try {
    logger.info(`Fetching proxies from ${source.url}`);

    const response = await httpClient.get(source.url, {
      timeout: 10000,
    });

    if (response.status !== 200) {
      logger.warn(`Failed to fetch from ${source.url}: ${response.status}`);
      return [];
    }

    const text = response.data;
    const lines = text.split('\n').filter((line: string) => line.trim());

    for (const line of lines) {
      let trimmed = line.trim();
      trimmed = cleanProxyUrl(trimmed);
      if (!trimmed || trimmed.startsWith('#')) continue;

      // Parse formats like "host:port" or "host:port:user:pass"
      const parts = trimmed.split(':');
      if (parts.length >= 2) {
        const proxy: ProxyInfo = {
          source: source.id,
          protocol: source.protocol as 'http' | 'https' | 'socks4' | 'socks5',
          host: parts[0],
          port: parseInt(parts[1]),
        };

        if (!isNaN(proxy.port) && proxy.host) {
          allProxies.push(proxy);
        }
      }
    }

    logger.info(`Parsed ${allProxies.length} proxies from ${source.url}`);
  } catch (error) {
    logger.error(`Error fetching proxies from ${source.url}`, error);
    return [];
  }

  return allProxies;
}

/**
 * Check if a proxy is working
 */
export async function checkProxy(proxy: ProxyInfo): Promise<ProxyInfo> {
  await initializeSharedResources();

  let success = false;
  logger.debug(`Checking Proxy:`, {
    protocol: proxy.protocol,
    host: proxy.host,
    port: proxy.port,
  });

  try {
    // Test the proxy
    const response = await httpClient.get(PROXY_CONFIG.CHECK_URL, {
      proxy,
      timeout: PROXY_CONFIG.CHECK_TIMEOUT,
    });

    const isWorking = response.status >= 200 && response.status < 300;
    const result: ProxyInfo = {
      ...proxy,
      isWorking,
      lastChecked: new Date(),
      responseTime: response.responseTime,
    };

    if (isWorking && !JSON.stringify(response.data).includes(PROXY_CONFIG.CHECK_IP)) {
      success = true;
      await updateProxyInCache(result, true);
    } else {
      await updateProxyInCache(result, false);
    }

    if (proxy.source) {
      await updateProxyStats(proxy.source, success);
    }

    logger.debug('Proxy check completed', {
      host: proxy.host,
      port: proxy.port,
      isWorking,
    });

    return result;
  } catch (error) {
    const errorMessage = error instanceof Error ? error.message : String(error);
    const result: ProxyInfo = {
      ...proxy,
      isWorking: false,
      error: errorMessage,
      lastChecked: new Date(),
    };

    // Update cache for failed proxy (increment total, don't update TTL)
    await updateProxyInCache(result, false);

    if (proxy.source) {
      await updateProxyStats(proxy.source, success);
    }

    logger.debug('Proxy check failed', {
      host: proxy.host,
      port: proxy.port,
      error: errorMessage,
    });

    return result;
  }
}

// Utility functions
function cleanProxyUrl(url: string): string {
  return url
    .replace(/^https?:\/\//, '')
    .replace(/^0+/, '')
    .replace(/:0+(\d)/g, ':$1');
}

function removeDuplicateProxies(proxies: ProxyInfo[]): ProxyInfo[] {
  const seen = new Set<string>();
  const unique: ProxyInfo[] = [];

  for (const proxy of proxies) {
    const key = `${proxy.protocol}://${proxy.host}:${proxy.port}`;
    if (!seen.has(key)) {
      seen.add(key);
      unique.push(proxy);
    }
  }

  return unique;
}

// Optional: Export a convenience object that groups related tasks
export const proxyTasks = {
  queueProxyFetch,
  queueProxyCheck,
  fetchProxiesFromSources,
  fetchProxiesFromSource,
  checkProxy,
};

// Export singleton instance for backward compatibility (optional)
// Remove this if you want to fully move to the task-based approach
export const proxyService = proxyTasks;