[mdcontentgen] generate content list for markdown

mdcontentgen.js

#!/usr/local/bin/node

var fs = require('fs');

var file = process.argv[2];
if (!file) throw 'no input file';

var seq = false;
if (file == '-s') {
    if (!process.argv[3]) throw 'no input file';
    seq = true;
    file = process.argv[3];
}

fs.readFile(file, 'utf8', function(err, buffer) {
    if (err) throw err;
    var lines = buffer.split('\n');
    var content = ['# Content'];
    var lv1No = 0;
    var lv2No = 0;
    var lv3No = 0;

    for (i in lines) {
        var title = /^(#+)\s+(<span id=".+">\s+)?([\d\.]+\s+)?(.+)/.exec(lines[i]);
        if (title) {
            var lv = title[1].length;
            var words = title[4].trim().split(' ');
            var id = words.join('-');
            var seqno = '';
            if (seq) {
                if (lv == 1) {
                    ++lv1No;
                    seqno = lv1No.toString();
                    lv2No = 0;
                    lv3No = 0;
                } else if (lv == 2) {
                    ++lv2No;
                    seqno = lv1No.toString() + '.' + lv2No.toString();
                    lv3No = 0;
                } else if (lv == 3) {
                    ++lv3No;
                    seqno = lv1No.toString() + '.' + lv2No.toString() + '.' + lv3No.toString();
                }
                seqno += ' ';
            }
            if (!title[2] || seq) { // not has archor or need add seq
                lines[i] = title[1] + ' <span id="' + id + '"> ' + seqno + title[4];
            }
            var indent = '';
            while (--lv) {
                indent += '\t';
            }
            content.push(indent + '* [' + seqno + title[4] + '](#' + id + ')');
        }
    }
    content.push('\n');

    var all = content.concat(lines).join('\n');
    fs.writeFile('New.'+file, all, function (err) {
        if (err) throw err;
        console.log('done!');
    });

});