import scala.io.Codec
import collection.mutable.{HashMap, MultiMap, Set}
import scala.xml.{NodeSeq, PrettyPrinter}
import java.util.Calendar
import java.text.SimpleDateFormat
import java.io.FileOutputStream
import java.nio.channels.Channels

import TermwikiParser._

object TermwikiExporter extends App {
  val usage = """
    Usage: <classname> dumpfile
  """
  type OptionMap = Map[Symbol, String]

  override def main(args: Array[String]) {
    if (args.length == 0) println(usage)
    val arglist = args.toList


    def nextOption(map : OptionMap, list: List[String]): OptionMap = {
      def isSwitch(s : String) = (s(0) == '-')
      list match {
        case Nil => map

        case string :: opt2 :: tail if isSwitch(opt2) =>
                               nextOption(map ++ Map('infile -> string), list.tail)
        case string :: Nil =>  nextOption(map ++ Map('infile -> string), list.tail)
        case option :: tail => println("Unknown option "+option)
                               sys.exit(1)
      }
    }
    val options = nextOption(Map(),arglist)
    process(options)
  }

  private def process(map: OptionMap) = {
    implicit val codec = Codec.UTF8
    val timeFormat = new SimpleDateFormat("yyyy-MM-dd")
    val timestamp = timeFormat.format(Calendar.getInstance().getTime())

    val file = Option(map).get('infile)
    val iterator = TermwikiParser.iterator(file)
    var termcenter: Set[NodeSeq] = Set()
    val termsLang = new HashMap[String, Set[NodeSeq]] with MultiMap[String, NodeSeq]

    iterator.foreach { term =>
      termcenter += term.toXml

      term.entries foreach {e => termsLang.addBinding(e.language, e.toXmlInLang(term.title))}
    }
    iterator.close()

    save(termcenter, "terms/termcenter.xml", "null", timestamp)
    termsLang foreach {l => save(l._2, "terms/terms-" + l._1 + ".xml", l._1, timestamp)}
  }

  private def save(nodes: Set[NodeSeq], fileName: String, lang: String, timestamp: String) = {
    val pp = new PrettyPrinter(80, 2)
    val fos = new FileOutputStream(fileName)
    val writer = Channels.newWriter(fos.getChannel(), "UTF-8")

    try {
      writer.write("<r xmlns:xi=\"http://www.w3.org/2001/XInclude\" id=\"termwiki\" xml:lang=\"" + lang + "\" timestamp=\"" + timestamp + "\">\n")
      nodes foreach { x => writer.write(pp.formatNodes(x)) }
      writer.write("</r>")
    } finally {
      writer.close()
    }
  }
}