package koushin import ( "fmt" "html/template" "io" "io/ioutil" "net/url" "os" "github.com/labstack/echo/v4" ) const themesDir = "public/themes" // GlobalRenderData contains data available in all templates. type GlobalRenderData struct { LoggedIn bool // if logged in Username string // TODO: list of mailboxes Extra map[string]interface{} } // RenderData is the base type for templates. It should be extended with new // template-specific fields. type RenderData struct { Global GlobalRenderData Extra map[string]interface{} } func NewRenderData(ctx *context) *RenderData { global := GlobalRenderData{Extra: make(map[string]interface{})} if ctx.session != nil { global.LoggedIn = true global.Username = ctx.session.username } return &RenderData{ Global: global, Extra: make(map[string]interface{}), } } type renderer struct { base *template.Template themes map[string]*template.Template defaultTheme string } func (r *renderer) Render(w io.Writer, name string, data interface{}, ectx echo.Context) error { // ectx is the raw *echo.context, not our own *context ctx := ectx.Get("context").(*context) for _, plugin := range ctx.server.plugins { if err := plugin.Inject(name, data); err != nil { return fmt.Errorf("failed to run plugin '%v': %v", plugin.Name(), err) } } // TODO: per-user theme selection t := r.base if r.defaultTheme != "" { t = r.themes[r.defaultTheme] } return t.ExecuteTemplate(w, name, data) } func loadTheme(name string, base *template.Template) (*template.Template, error) { theme, err := base.Clone() if err != nil { return nil, err } theme, err = theme.ParseGlob("public/themes/" + name + "/*.html") if err != nil { return nil, err } return theme, nil } func loadTemplates(logger echo.Logger, defaultTheme string, plugins []Plugin) (*renderer, error) { base := template.New("").Funcs(template.FuncMap{ "tuple": func(values ...interface{}) []interface{} { return values }, "pathescape": func(s string) string { return url.PathEscape(s) }, }) for _, p := range plugins { base = base.Funcs(p.Filters()) } base, err := base.ParseGlob("public/*.html") if err != nil { return nil, err } themes := make(map[string]*template.Template) files, err := ioutil.ReadDir(themesDir) if err != nil && !os.IsNotExist(err) { return nil, err } for _, fi := range files { if !fi.IsDir() { continue } logger.Printf("Loading theme '%v'", fi.Name()) var err error if themes[fi.Name()], err = loadTheme(fi.Name(), base); err != nil { return nil, fmt.Errorf("failed to load theme '%v': %v", fi.Name(), err) } } if defaultTheme != "" { if _, ok := themes[defaultTheme]; !ok { return nil, fmt.Errorf("failed to find default theme '%v'", defaultTheme) } } return &renderer{ base: base, themes: themes, defaultTheme: defaultTheme, }, nil }