import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';
import crypto from 'crypto';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

const CSV_PATHS = [
  '/Users/marcmintel/Downloads/pages.csv',
  '/Users/marcmintel/Downloads/pages(1).csv',
  '/Users/marcmintel/Downloads/pages(2).csv',
];
const JSON_OUTPUT_PATH = path.join(__dirname, '../data/umami-import-merged.json');
const SQL_OUTPUT_PATH = path.join(__dirname, '../data/umami-import-new.sql');
const WEBSITE_ID = '59a7db94-0100-4c7e-98ef-99f45b17f9c3';
const HOSTNAME = 'klz-cables.com';

function parseCSV(content: string) {
  const lines = content.split('\n');
  if (lines.length === 0) return [];
  const headers = lines[0].split(',').map((h) => h.trim().replace(/^"|"$/g, ''));
  const data = [];

  for (let i = 1; i < lines.length; i++) {
    if (!lines[i].trim()) continue;

    // Simple CSV parser that handles quotes
    const values: string[] = [];
    let current = '';
    let inQuotes = false;
    for (let j = 0; j < lines[i].length; j++) {
      const char = lines[i][j];
      if (char === '"') inQuotes = !inQuotes;
      else if (char === ',' && !inQuotes) {
        values.push(current.trim());
        current = '';
      } else {
        current += char;
      }
    }
    values.push(current.trim());

    const row: any = {};
    headers.forEach((header, index) => {
      row[header] = values[index]?.replace(/^"|"$/g, '');
    });
    data.push(row);
  }
  return data;
}

function normalizeURL(url: string) {
  if (!url) return '/';
  if (url.startsWith('http')) {
    try {
      return new URL(url).pathname;
    } catch {
      return url;
    }
  }
  return url.startsWith('/') ? url : `/${url}`;
}

async function mergeData() {
  console.log('Reading CSVs...');
  const aggregatedData: Record<string, { views: number; visitors: number; title: string }> = {};

  for (const csvPath of CSV_PATHS) {
    if (!fs.existsSync(csvPath)) {
      console.warn(`File not found: ${csvPath}`);
      continue;
    }
    const csvContent = fs.readFileSync(csvPath, 'utf-8');
    const csvData = parseCSV(csvContent);

    for (const row of csvData) {
      const url = normalizeURL(row.URL);
      const views = parseInt(row.Views) || 0;
      const visitors = parseInt(row.Visitors) || 0;
      const title = row.Title || '';

      if (!aggregatedData[url]) {
        aggregatedData[url] = { views, visitors, title };
      } else {
        aggregatedData[url].views = Math.max(aggregatedData[url].views, views);
        aggregatedData[url].visitors = Math.max(aggregatedData[url].visitors, visitors);
        if (!aggregatedData[url].title && title) {
          aggregatedData[url].title = title;
        }
      }
    }
  }

  const jsonEvents = [];
  const sqlStatements = [];

  // Spread data across the whole period since early 2025 launch
  const START_DATE = new Date('2025-01-01T08:00:00Z');
  const END_DATE = new Date('2026-02-13T20:00:00Z');
  const startTs = START_DATE.getTime();
  const endTs = END_DATE.getTime();
  const totalDays = Math.ceil((endTs - startTs) / (1000 * 60 * 60 * 24));

  // Cleanup for the target period
  sqlStatements.push(`-- Cleanup previous artificial imports (Full Year 2025 and 2026 until now)
DELETE FROM website_event WHERE website_id = '${WEBSITE_ID}' AND created_at >= '2025-01-01 00:00:00' AND created_at <= '2026-02-13 23:59:59' AND hostname = '${HOSTNAME}';
DELETE FROM session WHERE website_id = '${WEBSITE_ID}' AND created_at >= '2025-01-01 00:00:00' AND created_at <= '2026-02-13 23:59:59';
`);

  // Helper for weighted random date selection
  function getRandomWeightedDate() {
    while (true) {
      const randomDays = Math.random() * totalDays;
      const date = new Date(startTs + randomDays * 24 * 60 * 60 * 1000);

      // 1. Growth Factor (0.2 at start to 1.0 at end)
      const growthWeight = 0.2 + (randomDays / totalDays) * 0.8;

      // 2. Weekend Factor (30% traffic on weekends)
      const dayOfWeek = date.getDay();
      const weekendWeight = dayOfWeek === 0 || dayOfWeek === 6 ? 0.3 : 1.0;

      // 3. Seasonality (simple sine wave)
      const month = date.getMonth();
      const seasonWeight = 0.8 + Math.sin((month / 12) * Math.PI * 2) * 0.2;

      // Combined weight
      const combinedWeight = growthWeight * weekendWeight * seasonWeight;

      // Pick based on weight
      if (Math.random() < combinedWeight) {
        // Return timestamp with random hour/minute
        date.setHours(Math.floor(Math.random() * 12) + 8); // Business hours mostly
        date.setMinutes(Math.floor(Math.random() * 60));
        return date;
      }
    }
  }

  const urls = Object.keys(aggregatedData);
  console.log(`Processing ${urls.length} aggregated URLs...`);

  for (const url of urls) {
    const { views, visitors, title } = aggregatedData[url];
    if (views === 0) continue;

    // We distribute views across visitors
    const sessionData = [];
    for (let v = 0; v < (visitors || 1); v++) {
      const sessionId = crypto.randomUUID();
      const visitId = crypto.randomUUID();

      const sessionDate = getRandomWeightedDate();
      const dateStr = sessionDate.toISOString().replace('T', ' ').split('.')[0];

      sessionData.push({ sessionId, visitId, date: sessionDate });

      sqlStatements.push(`INSERT INTO session (session_id, website_id, browser, os, device, screen, language, country, created_at)
        VALUES ('${sessionId}', '${WEBSITE_ID}', 'Chrome', 'Windows', 'desktop', '1920x1080', 'en', 'DE', '${dateStr}')
        ON CONFLICT (session_id) DO NOTHING;`);
    }

    // Distribute views across these sessions
    for (let i = 0; i < views; i++) {
      const sIdx = i % sessionData.length;
      const session = sessionData[sIdx];
      const sessionId = session.sessionId;
      const visitId = session.visitId;
      const eventId = crypto.randomUUID();

      // Event date should be close to session date
      const eventDate = new Date(session.date.getTime() + Math.random() * 1000 * 60 * 30); // within 30 mins
      const timestamp = eventDate.toISOString();
      const dateStr = timestamp.replace('T', ' ').split('.')[0];

      // JSON Format
      jsonEvents.push({
        website_id: WEBSITE_ID,
        hostname: HOSTNAME,
        path: url,
        referrer: '',
        event_name: null,
        pageview: true,
        session: true,
        duration: Math.floor(Math.random() * 120) + 10,
        created_at: timestamp,
      });

      // SQL Format
      sqlStatements.push(`INSERT INTO website_event (event_id, website_id, session_id, created_at, url_path, url_query, referrer_path, referrer_query, referrer_domain, page_title, event_type, event_name, visit_id, hostname)
        VALUES ('${eventId}', '${WEBSITE_ID}', '${sessionId}', '${dateStr}', '${url}', '', '', '', '', '${title.replace(/'/g, "''")}', 1, NULL, '${visitId}', '${HOSTNAME}');`);
    }
  }

  console.log(`Writing ${jsonEvents.length} events to ${JSON_OUTPUT_PATH}...`);
  fs.writeFileSync(JSON_OUTPUT_PATH, JSON.stringify(jsonEvents, null, 2));

  console.log(`Writing SQL statements to ${SQL_OUTPUT_PATH}...`);
  fs.writeFileSync(SQL_OUTPUT_PATH, sqlStatements.join('\n'));

  console.log('✅ Refined Restoration Script complete!');
}

mergeData().catch(console.error);