/* Any copyright is dedicated to the Public Domain.
 * http://creativecommons.org/publicdomain/zero/1.0/ */

//
// Basic node example that prints document metadata and text content.
// Requires single file built version of PDF.js -- please run
// `gulp singlefile` before running the example.
//

var fs = require('fs');

// Run `gulp dist-install` to generate 'pdfjs-dist' npm package files.
var pdfjsLib = require('pdfjs-dist');

// Loading file from file system into typed array
var pdfPath = process.argv[2] || '../../web/compressed.tracemonkey-pldi-09.pdf';

// Will be using promises to load document, pages and misc data instead of
// callback.
pdfjsLib.getDocument(pdfPath).then(function (doc) {
  var numPages = doc.numPages;
  console.log('# Document Loaded');
  console.log('Number of Pages: ' + numPages);
  console.log();

  var lastPromise; // will be used to chain promises
  lastPromise = doc.getMetadata().then(function (data) {
    console.log('# Metadata Is Loaded');
    console.log('## Info');
    console.log(JSON.stringify(data.info, null, 2));
    console.log();
    if (data.metadata) {
      console.log('## Metadata');
      console.log(JSON.stringify(data.metadata.getAll(), null, 2));
      console.log();
    }
  });

  var loadPage = function (pageNum) {
    return doc.getPage(pageNum).then(function (page) {
      console.log('# Page ' + pageNum);
      var viewport = page.getViewport(1.0 /* scale */);
      console.log('Size: ' + viewport.width + 'x' + viewport.height);
      console.log();
      return page.getTextContent().then(function (content) {
        // Content contains lots of information about the text layout and
        // styles, but we need only strings at the moment
        var strings = content.items.map(function (item) {
          return item.str;
        });
        console.log('## Text Content');
        console.log(strings.join(' '));
      }).then(function () {
        console.log();
      });
    })
  };
  // Loading of the first page will wait on metadata and subsequent loadings
  // will wait on the previous pages.
  for (var i = 1; i <= numPages; i++) {
    lastPromise = lastPromise.then(loadPage.bind(null, i));
  }
  return lastPromise;
}).then(function () {
  console.log('# End of Document');
}, function (err) {
  console.error('Error: ' + err);
});