module TexHeaderHelper

open System.IO

let addLine (wr: StreamWriter, line:string) =
  wr.WriteLine(line)

let mainHeader (wr:StreamWriter) =
  addLine(wr ,"\documentclass[a4paper,12pt]{article}")
  addLine(wr, "\usepackage[T2A]{fontenc}")
  addLine(wr, "\usepackage[utf8]{inputenc}")
  addLine(wr, "\usepackage[russian,english]{babel}")
  addLine(wr, "\usepackage[pdftex,unicode]{hyperref}")
  addLine(wr, "\usepackage{indentfirst}")

let author(wr:StreamWriter, title:string, author:string, date:string) =
  addLine(wr, "\title{" + title + "}")
  addLine(wr, "\author{" + author + "}")
  addLine(wr, "\date{" + date + "}")

let startDocument(wr:StreamWriter) =
   addLine(wr, "begin{document}")