import { readFile } from 'node:fs/promises';
import { parseLine } from './parsing.mjs';
import { buildIntervalsCrossDay } from './intervals.mjs';
import { exportCSV } from './csv.mjs';
import { NamesServiceProxy } from './namesProxy.mjs';

class GenericDriver {
  constructor(){
    if (GenericDriver._instance) return GenericDriver._instance;
    /** @type {Array<Object>} */ this.parsedRows = [];
    /** @type {Array<Object>} */ this.payloadDB  = [];
    /** @type {Array<Object>} */ this.pairs      = [];
    GenericDriver._instance = this;
  }

  // Orquesta el proceso a partir de texto plano
  async processText(text, { fetchNamesForDocs } = {}){
    const lines = String(text||'').split(/\n/);
    const rows = [];
    for (const line of lines) {
      const r = parseLine(line);
      if (r) rows.push(r);
    }
    this.parsedRows = rows;

    const uniqueDocs = [...new Set(this.parsedRows.map(r => r.doc))];

    const namesProxy = new NamesServiceProxy(fetchNamesForDocs);
    const map = await namesProxy.get(uniqueDocs);

    const missingDocs = uniqueDocs.filter(d => {
      const hit = map?.[d];
      if (!hit) return true;
      if (typeof hit.found === 'boolean') return !hit.found;
      return !(hit?.nombre||'').trim() && !(hit?.apellido||'').trim();
    });

    // sobreescribir nombre cuando DB provee
    this.parsedRows.forEach(r => {
      const hit = map?.[r.doc];
      if (hit && (hit.nombre || hit.apellido)) {
        r.name = `${hit.nombre || ''} ${hit.apellido || ''}`.trim();
      }
    });

    // Pairs (permitiendo cruce de medianoche)
    this.pairs = buildIntervalsCrossDay(this.parsedRows);

    // Payload crudo para insertar
    this.payloadDB = this.parsedRows.map(r => ({
      doc: r.doc,
      isoDate: r.isoDate,
      time: r.time,
      mode: r.mode || null
    }));

    return { parsedRows: this.parsedRows, pairs: this.pairs, payloadDB: this.payloadDB, missingDocs };
  }

  // Conveniencia: leer desde ruta en disco
  async processFileFromPath(filePath, opts = {}){
    const txt = await readFile(filePath, 'utf8');
    return await this.processText(txt, opts);
  }

  // CSV server-side (devuelve string)
  exportCSV(pairs = this.pairs){
    return exportCSV(pairs);
  }
}

const instance = new GenericDriver();
export default instance;
export { GenericDriver };