import pg from 'pg';
import { logger } from '../observability/logger.js';

const { Pool } = pg;

// TIP database on Erik (IONOS VPS)
const TIP_DB_CONFIG = {
  host: process.env['TIP_DB_HOST'] ?? '82.165.222.127',
  port: parseInt(process.env['TIP_DB_PORT'] ?? '5433', 10),
  database: process.env['TIP_DB_NAME'] ?? 'transceiver_db',
  user: process.env['TIP_DB_USER'] ?? 'tip',
  password: process.env['TIP_DB_PASSWORD']!,
  max: 5,
  idleTimeoutMillis: 60_000,
  connectionTimeoutMillis: 10_000,
  ssl: process.env['TIP_DB_SSL'] === 'true' ? { rejectUnauthorized: false } : false,
};

let tipPool: pg.Pool | null = null;

function getTipPool(): pg.Pool {
  if (!tipPool) {
    tipPool = new Pool(TIP_DB_CONFIG);
    tipPool.on('error', (err) => {
      logger.error({ err }, 'TIP database pool error');
    });
    tipPool.on('connect', () => {
      logger.debug('TIP database connection established');
    });
  }
  return tipPool;
}

export interface TransceiverRecord {
  id: string;
  part_number: string;
  vendor: string;
  form_factor: string;
  data_rate_gbps: number;
  wavelength_nm: number | null;
  fiber_type: string;
  connector: string;
  reach_m: number | null;
  temperature_class: string;
  price_usd: number | null;
  compatible_with: string[];
  sff8024_identifier: string | null;
  created_at: string;
  updated_at: string;
}

export interface PriceRecord {
  vendor: string;
  part_number: string;
  price_usd: number;
  currency: string;
  source_url: string;
  scraped_at: string;
}

export async function lookupTransceiver(partNumber: string): Promise<TransceiverRecord | null> {
  const pool = getTipPool();
  try {
    const result = await pool.query<TransceiverRecord>(
      `SELECT * FROM transceivers WHERE UPPER(part_number) = UPPER($1) LIMIT 1`,
      [partNumber],
    );
    return result.rows[0] ?? null;
  } catch (err) {
    logger.warn({ err, partNumber }, 'TIP DB transceiver lookup failed');
    return null;
  }
}

export async function lookupByFormFactor(
  formFactor: string,
  dataRateGbps?: number,
): Promise<TransceiverRecord[]> {
  const pool = getTipPool();
  try {
    const params: unknown[] = [formFactor];
    let sql = `SELECT * FROM transceivers WHERE UPPER(form_factor) = UPPER($1)`;
    if (dataRateGbps !== undefined) {
      params.push(dataRateGbps);
      sql += ` AND data_rate_gbps = $2`;
    }
    sql += ` ORDER BY price_usd ASC NULLS LAST LIMIT 20`;
    const result = await pool.query<TransceiverRecord>(sql, params);
    return result.rows;
  } catch (err) {
    logger.warn({ err, formFactor }, 'TIP DB form factor lookup failed');
    return [];
  }
}

export async function getPriceHistory(
  partNumber: string,
  vendor?: string,
  daysBack = 30,
): Promise<PriceRecord[]> {
  const pool = getTipPool();
  try {
    const params: unknown[] = [partNumber, daysBack];
    let sql = `
      SELECT vendor, part_number, price_usd, currency, source_url, scraped_at
      FROM price_history
      WHERE UPPER(part_number) = UPPER($1)
        AND scraped_at > NOW() - INTERVAL '$2 days'
    `;
    if (vendor) {
      params.push(vendor);
      sql += ` AND UPPER(vendor) = UPPER($${params.length})`;
    }
    sql += ` ORDER BY scraped_at DESC LIMIT 100`;
    const result = await pool.query<PriceRecord>(sql, params);
    return result.rows;
  } catch (err) {
    logger.warn({ err, partNumber }, 'TIP DB price history lookup failed');
    return [];
  }
}

export async function getVendorList(): Promise<string[]> {
  const pool = getTipPool();
  try {
    const result = await pool.query<{ vendor: string }>(
      `SELECT DISTINCT vendor FROM transceivers WHERE vendor IS NOT NULL ORDER BY vendor`,
    );
    return result.rows.map((r) => r.vendor);
  } catch (err) {
    logger.warn({ err }, 'TIP DB vendor list lookup failed');
    return [];
  }
}

export async function closeTipPool(): Promise<void> {
  if (tipPool) {
    await tipPool.end();
    tipPool = null;
  }
}

export async function testTipConnection(): Promise<boolean> {
  const pool = getTipPool();
  try {
    await pool.query('SELECT 1');
    return true;
  } catch (err) {
    logger.warn({ err }, 'TIP DB connection test failed');
    return false;
  }
}