import axios from 'axios';
import { classifySector } from './classify-sector.js';
import pg from 'pg';
import dotenv from 'dotenv';

dotenv.config();

const pool = new pg.Pool({
  connectionString: process.env.DATABASE_URL || 'postgresql://tenderpilot:tenderpilot123@localhost:5432/tenderpilot'
});

async function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
}

async function scrapeTenders() {
  try {
    console.log(`[${new Date().toISOString()}] Starting tender scrape...`);
    
    // Get date from 90 days ago
    const fromDate = new Date();
    fromDate.setDate(fromDate.getDate() - 90);
    const dateStr = fromDate.toISOString().split('T')[0];
    
    const baseUrl = `https://www.contractsfinder.service.gov.uk/Published/Notices/OCDS/Search?stage=tender&output=json&publishedFrom=${dateStr}`;
    
    console.log(`Base URL: ${baseUrl}`);
    
    let insertedCount = 0;
    let totalProcessed = 0;
    let pageNum = 1;
    let hasNextPage = true;
    let nextPageUrl = baseUrl;
    
    while (hasNextPage) {
      try {
        console.log(`\nFetching page ${pageNum}...`);
        const response = await axios.get(nextPageUrl, { timeout: 30000 });
        
        const data = response.data;
        const releases = data.releases || [];
        
        for (const release of releases) {
          try {
            const tender = release.tender || {};
            const planning = release.planning || {};
            const parties = release.parties || [];
            
            // Find procuring entity
            const procurer = parties.find(p => p.roles && (p.roles.includes('buyer') || p.roles.includes('procuringEntity') || p.roles.includes('procurer'))) || (release.buyer ? release.buyer : null);
            
            const sourceId = release.ocid || release.id;
            const title = tender.title || 'Untitled';
            const description = tender.description || '';
            const publishedDate = release.date;
            const deadline = tender.tenderPeriod?.endDate;
        
        // Skip expired tenders
        if (deadline && new Date(deadline) < new Date()) continue;
            const authority = procurer?.name || 'Unknown';
            const location = planning?.budget?.description || tender.procurementMethod || '';
            const noticeUrl = release.url || 'https://www.contractsfinder.service.gov.uk/Search';
            const documentsUrl = tender.documents?.length > 0 ? tender.documents[0].url : '';
            
            // Extract value
            let valueLow = null, valueHigh = null;
            if (planning?.budget?.amount?.amount) {
              valueLow = planning.budget.amount.amount;
              valueHigh = planning.budget.amount.amount;
            } else if (tender.value?.amount) {
              valueLow = tender.value.amount;
              valueHigh = tender.value.amount;
            }
            
            const cpvCodes = tender.classification ? [tender.classification.scheme] : [];
            
            const result = await pool.query(
              `INSERT INTO tenders (
                source, source_id, title, description, summary, cpv_codes,
                value_low, value_high, currency, published_date, deadline,
                authority_name, authority_type, location, documents_url, notice_url, status, sector
              ) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15, $16, $17, $18)
               ON CONFLICT (source_id) DO NOTHING`,
              [
                'contracts_finder',
                sourceId,
                title.substring(0, 500),
                description,
                description.substring(0, 500),
                cpvCodes,
                valueLow,
                valueHigh,
                'GBP',
                publishedDate,
                deadline,
                authority,
                'government',
                location.substring(0, 255),
                documentsUrl,
                noticeUrl,
                'open',
                classifySector(title, description, authority)
              ]
            );
            if (result.rowCount > 0) {
              insertedCount++;
            }
            totalProcessed++;
          } catch (e) {
            console.error('Error inserting tender:', e.message);
          }
        }
        
        console.log(`Page ${pageNum}: fetched ${releases.length} tenders (total: ${totalProcessed})`);
        
        // Check for next page
        if (data.links && data.links.next) {
          nextPageUrl = data.links.next;
          hasNextPage = true;
          pageNum++;
          // Add 1 second delay between pages to avoid rate limiting
          await sleep(1000);
        } else {
          hasNextPage = false;
        }
      } catch (error) {
        console.error(`Error fetching page ${pageNum}:`, error.message);
        hasNextPage = false;
      }
    }
    
    console.log(`\n[${new Date().toISOString()}] Scrape complete. Inserted ${insertedCount} new tenders (total processed: ${totalProcessed})`);
  } catch (error) {
    console.error('Error scraping tenders:', error.message);
  } finally {
    await pool.end();
  }
}

scrapeTenders();