// Compile all section-1 slides into a single PPTX
// Output: section1.pptx (27 slides, 16:9, dark theme, code-heavy)

const path = require('path');
const fs = require('fs');
const pptxgen = require('pptxgenjs');

const ds = require('./design-system');
const { theme } = ds;

const pres = new pptxgen();
pres.layout = 'LAYOUT_16x9';
pres.title = 'LangChain 1.0: chains, LCEL, agents, retrievers';
pres.author = 'lc-evo-deck';
pres.subject = 'Section 1 of the LangChain Evolution deck';

const SLIDE_COUNT = 27;

for (let i = 1; i <= SLIDE_COUNT; i++) {
  const num = String(i).padStart(2, '0');
  const file = path.join(__dirname, `slide-${num}.js`);
  if (!fs.existsSync(file)) {
    throw new Error('Missing slide module: ' + file);
  }
  const mod = require(file);
  if (typeof mod.createSlide !== 'function') {
    throw new Error('Module does not export createSlide: ' + file);
  }
  mod.createSlide(pres, theme);
}

const outFile = path.join(__dirname, 'section1.pptx');
pres.writeFile({ fileName: outFile })
  .then((fileName) => {
    console.log('OK ->', fileName);
    console.log('Slides:', SLIDE_COUNT);
  })
  .catch((err) => {
    console.error('ERR:', err);
    process.exit(1);
  });