Files
liberama/server/core/BookConverter/ConvertPdf.js

128 lines
3.9 KiB
JavaScript

const fs = require('fs-extra');
const sax = require('./sax');
const utils = require('../utils');
const ConvertHtml = require('./ConvertHtml');
class ConvertPdf extends ConvertHtml {
check(data, opts) {
const {inputFiles} = opts;
return this.config.useExternalBookConverter &&
inputFiles.sourceFileType && inputFiles.sourceFileType.ext == 'pdf';
}
async run(notUsed, opts) {
if (!this.check(notUsed, opts))
return false;
await this.checkExternalConverterPresent();
const {inputFiles, callback} = opts;
const outFile = `${inputFiles.fileListDir}/${utils.randomHexString(10)}.xml`;
//конвертируем в xml
await this.execConverter(this.pdfToHtmlPath, ['-c', '-s', '-xml', inputFiles.sourceFile, outFile]);
callback(50);
const data = await fs.readFile(outFile);
callback(60);
//парсим xml
let lines = [];
let inText = false;
let title = '';
let i = -1;
const onTextNode = (text, cutCounter, cutTag) => {// eslint-disable-line no-unused-vars
if (!cutCounter && inText) {
lines[i].text += text + ' ';
if (i < 2)
title += text + ' ';
}
};
const onStartNode = (tag, tail, singleTag, cutCounter, cutTag) => {// eslint-disable-line no-unused-vars
if (!cutCounter) {
if (tag == 'text' && !inText) {
let attrs = sax.getAttrsSync(tail);
const line = {
text: '',
top: (attrs.top && attrs.top.value ? attrs.top.value : null),
left: (attrs.left && attrs.left.value ? attrs.left.value : null),
width: (attrs.width && attrs.width.value ? attrs.width.value : null),
height: (attrs.height && attrs.height.value ? attrs.height.value : null),
};
if (line.width !== '0' || line.height !== '0') {
inText = true;
i++;
lines[i] = line;
}
}
}
};
const onEndNode = (tag, tail, singleTag, cutCounter, cutTag) => {// eslint-disable-line no-unused-vars
if (tag == 'text')
inText = false;
};
let buf = this.decode(data).toString();
sax.parseSync(buf, {
onStartNode, onEndNode, onTextNode
});
//найдем параграфы и отступы
const indents = [];
for (const line of lines) {
const top = parseInt(line.top);
const left = parseInt(line.left);
if (!isNaN(top)) {
line.top = top;
}
if (!isNaN(left)) {
indents[left] = 1;
line.left = left;
}
}
let j = 0;
for (let i = 0; i < indents.length; i++) {
if (indents[i]) {
j++;
indents[i] = j;
}
}
indents[0] = 0;
//формируем текст
let text = `<title>${title}</title>`;
let concat = '';
let sp = '';
for (const line of lines) {
if (concat == '') {
const left = line.left || 0;
sp = ' '.repeat(indents[left]);
}
let t = line.text.trim();
if (t.substr(-1) == '-') {
t = t.substr(0, t.length - 1);
concat += t;
} else {
text += sp + concat + t + "\n";
concat = '';
}
}
if (concat)
text += sp + concat + "\n";
return await super.run(Buffer.from(text), {skipCheck: true, isText: true, cutTitle: true});
}
}
module.exports = ConvertPdf;