package wikipediadl

import (
	"compress/bzip2"
	"encoding/xml"
	"errors"
	"io"
	"log"
	"net/http"
)

type WikiArticle struct {
	Title    string   `xml:"title"`
	Revision Revision `xml:"revision"`
}

type Revision struct {
	Text string `xml:"text"`
}

func ExtractArticles(bundle string) ([]WikiArticle, error) {
	url := WikipediaDumpUrl + bundle

	resp, err := http.Get(url)
	if err != nil {
		log.Println(err.Error())
		return nil, errors.New("wikipediadl: failed load articles")
	}

	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		return nil, errors.New("wikipediadl: bad response status")
	}

	bz2Reader := bzip2.NewReader(resp.Body)
	xmlDec := xml.NewDecoder(bz2Reader)

	count := 0

	articles := []WikiArticle{}
Loop:
	for {
		tok, err := xmlDec.Token()
		if err != nil {
			if err == io.EOF {
				break
			}

			return nil, errors.New("XML token error")
		}

		switch se := tok.(type) {
		case xml.StartElement:
			if count == 2 { // XXX: remove later
				break Loop
			}

			if se.Name.Local != "page" {
				continue
			}

			var p WikiArticle
			if err := xmlDec.DecodeElement(&p, &se); err != nil {
				log.Println(err.Error())
				continue
			}

			articles = append(articles, p)
			count++ // XXX: remove later
		}
	}

	return articles, nil
}