package templates
import (
"html/template"
"io"
"path"
"strings"
"github.com/phc-dm/phc-server/config"
"github.com/phc-dm/phc-server/util"
)
type LoadTemplate interface {
Load(t *template.Template) (*template.Template, error)
}
type File string
func (file File) Load(t *template.Template) (*template.Template, error) {
return t.ParseFiles(string(file))
}
type Pattern string
func (pattern Pattern) Load(t *template.Template) (*template.Template, error) {
return t.ParseGlob(string(pattern))
}
type CachedTemplate struct {
Loaders []LoadTemplate
template *template.Template
}
func NewCacheTemplate(loaders ...LoadTemplate) *CachedTemplate {
cachedTemplate := &CachedTemplate{
Loaders: loaders,
template: nil,
}
template.Must(cachedTemplate.Load(template.New("")))
return cachedTemplate
}
func (ct *CachedTemplate) Load(t *template.Template) (*template.Template, error) {
if ct.template != nil {
return ct.template, nil
}
ct.template = t
for _, loader := range ct.Loaders {
var err error
ct.template, err = loader.Load(ct.template)
if err != nil {
return nil, err
}
}
return ct.template, nil
}
func (ct *CachedTemplate) Reload() {
ct.template = nil
template.Must(ct.Load(nil))
}
func (ct *CachedTemplate) Template() *template.Template {
return ct.template
}
// Renderer holds cached templates for rendering
type Renderer struct {
rootPath string
baseLoaders []LoadTemplate
routes map[string]*CachedTemplate
}
// NewRenderer constructs a template renderer with a base file
func NewRenderer(rootPath string, loaders ...LoadTemplate) *Renderer {
return &Renderer{
rootPath,
loaders,
map[string]*CachedTemplate{},
}
}
func (r *Renderer) Load(name string) *CachedTemplate {
cachedTemplate, present := r.routes[name]
if !present {
loaders := []LoadTemplate{}
loaders = append(loaders, r.baseLoaders...)
loaders = append(loaders, File(path.Join(r.rootPath, name)))
cachedTemplate = NewCacheTemplate(loaders...)
r.routes[name] = cachedTemplate
}
return cachedTemplate
}
// Render the template, also injects "Page" and "Config" values in the template
func (r *Renderer) Render(w io.Writer, name string, data util.H) error {
cachedTemplate := r.Load(name)
if config.Mode == "development" {
cachedTemplate.Reload()
}
newData := util.H{}
newData.Apply(data)
newData["Page"] = util.H{
// Used to inject a page specific class on
"Name": strings.TrimSuffix(path.Base(name), ".html"),
}
newData["Config"] = config.Object()
return cachedTemplate.Template().ExecuteTemplate(w, "base", newData)
}