trantor/lib/template.go

package trantor

import (
	html_tmpl "html/template"
	txt_tmpl "text/template"

	log "github.com/cihub/seelog"

	"encoding/json"
	"errors"
	"net/http"
	"path"
	"time"

	"gitlab.com/trantor/trantor/lib/database"
)

type Status struct {
	BaseURL  string
	FullURL  string
	Title    string
	Search   string
	User     string
	IsAdmin  bool
	Notif    []Notification
	Updated  string
	Home     bool
	About    bool
	News     bool
	Upload   bool
	Stats    bool
	Help     bool
	Dasboard bool
}

func GetStatus(h handler) Status {
	var s Status
	s.BaseURL = "http://" + h.hostname
	s.FullURL = s.BaseURL + h.r.RequestURI
	s.Title = "Imperial Library of Trantor"
	s.User = h.sess.User
	s.IsAdmin = h.sess.IsAdmin()
	s.Notif = h.sess.GetNotif()
	s.Updated = time.Now().UTC().Format("2006-01-02T15:04:05Z")
	h.sess.Save(h.w, h.r)
	return s
}

type Template struct {
	tmpl_html *html_tmpl.Template
	tmpl_rss  *txt_tmpl.Template
	tmpl_opds *txt_tmpl.Template
}

func InitTemplate(assetsPath string) *Template {
	var t Template
	templatePath := path.Join(assetsPath, "templates")

	t.tmpl_html = html_tmpl.Must(html_tmpl.ParseFiles(
		path.Join(templatePath, "header.html"),
		path.Join(templatePath, "footer.html"),
		path.Join(templatePath, "404.html"),
		path.Join(templatePath, "index.html"),
		path.Join(templatePath, "about.html"),
		path.Join(templatePath, "news.html"),
		path.Join(templatePath, "edit_news.html"),
		path.Join(templatePath, "book.html"),
		path.Join(templatePath, "search.html"),
		path.Join(templatePath, "upload.html"),
		path.Join(templatePath, "login.html"),
		path.Join(templatePath, "new.html"),
		path.Join(templatePath, "read.html"),
		path.Join(templatePath, "edit.html"),
		path.Join(templatePath, "dashboard.html"),
		path.Join(templatePath, "settings.html"),
		path.Join(templatePath, "stats.html"),
		path.Join(templatePath, "help.html"),
	))

	t.tmpl_rss = txt_tmpl.Must(txt_tmpl.ParseFiles(
		path.Join(templatePath, "search.rss"),
		path.Join(templatePath, "news.rss"),
	))

	t.tmpl_opds = txt_tmpl.Must(txt_tmpl.ParseFiles(
		path.Join(templatePath, "index.opds"),
		path.Join(templatePath, "search.opds"),
	))

	return &t
}

func (t Template) load(h handler, tmpl string, data interface{}) {
	var err error
	fmt := h.r.FormValue("fmt")
	switch fmt {
	case "rss":
		err = t.tmpl_rss.ExecuteTemplate(h.w, tmpl+".rss", data)
	case "opds":
		err = t.tmpl_opds.ExecuteTemplate(h.w, tmpl+".opds", data)
	case "json":
		err = loadJson(h.w, tmpl, data)
	default:
		err = t.tmpl_html.ExecuteTemplate(h.w, tmpl+".html", data)
	}
	if err != nil {
		t.tmpl_html.ExecuteTemplate(h.w, "404.html", data)
		log.Warn("An error ocurred loading the template ", tmpl, ".", fmt, ": ", err)
	}
}

func loadJson(w http.ResponseWriter, tmpl string, data interface{}) error {
	var res []byte
	var err error
	switch tmpl {
	case "index":
		res, err = indexJson(data)
	case "book":
		res, err = bookJson(data)
	case "news":
		res, err = newsJson(data)
	case "search":
		res, err = searchJson(data)
	}
	if err != nil {
		return err
	}
	_, err = w.Write(res)
	return err
}

func indexJson(data interface{}) ([]byte, error) {
	index, ok := data.(indexData)
	if !ok {
		return nil, errors.New("Data is not valid")
	}

	books := make([]map[string]interface{}, len(index.Books))
	for i, book := range index.Books {
		books[i] = bookJsonRaw(book)
	}
	news := newsJsonRaw(index.News)

	return json.Marshal(map[string]interface{}{
		"title":      index.S.Title,
		"url":        index.S.BaseURL,
		"count":      index.Count,
		"news":       news,
		"tags":       index.Tags,
		"last_added": books,
	})
}

func bookJson(data interface{}) ([]byte, error) {
	book, ok := data.(bookData)
	if !ok {
		return nil, errors.New("Data is not valid")
	}

	return json.Marshal(bookJsonRaw(book.Book))
}

func newsJson(data interface{}) ([]byte, error) {
	news, ok := data.(newsData)
	if !ok {
		return nil, errors.New("Data is not valid")
	}

	return json.Marshal(newsJsonRaw(news.News))
}

func newsJsonRaw(news []newsEntry) []map[string]string {
	list := make([]map[string]string, len(news))
	for i, n := range news {
		list[i] = map[string]string{
			"date": n.Date,
			"text": n.Text,
		}
	}
	return list
}

func searchJson(data interface{}) ([]byte, error) {
	search, ok := data.(searchData)
	if !ok {
		return nil, errors.New("Data is not valid")
	}

	books := make([]map[string]interface{}, len(search.Books))
	for i, book := range search.Books {
		books[i] = bookJsonRaw(book)
	}
	return json.Marshal(map[string]interface{}{
		"found": search.Found,
		"page":  search.Page - 1,
		"items": search.ItemsPage,
		"books": books,
	})
}

func bookJsonRaw(book database.Book) map[string]interface{} {
	cover := ""
	coverSmall := ""
	if book.Cover {
		cover = "/cover/" + book.Id + "/big/" + book.Title + ".jpg"
		coverSmall = "/cover/" + book.Id + "/small/" + book.Title + ".jpg"
	}
	return map[string]interface{}{
		"id":          book.Id,
		"title":       book.Title,
		"author":      book.Author,
		"contributor": book.Contributor,
		"publisher":   book.Publisher,
		"description": book.Description,
		"subject":     book.Subject,
		"date":        book.Date,
		"lang":        book.Lang,
		"isbn":        book.Isbn,
		"size":        book.FileSize,
		"cover":       cover,
		"cover_small": coverSmall,
		"download":    "/download/" + book.Id + "/" + book.Title + ".epub",
		"read":        "/read/" + book.Id,
	}
}