package util

import (
	"path"
	"text/template"
	"time"
)

func NewTemplate(filenames ...string) *template.Template {
	return template.Must(template.New(path.Base(filenames[0])).
		Funcs(template.FuncMap{
			// Form input helpers
			"value": func(v interface{}) string {
				if v == nil {
					return ""
				}
				return "value=\"" + template.HTMLEscapeString(v.(string)) + "\""
			},
			"checked": func(v1 interface{}, v2 interface{}) string {
				if v1 == nil || v2 == nil {
					return ""
				}
				if v1 == v2 {
					return "checked"
				}
				return ""
			},
			"selected": func(v1 interface{}, v2 interface{}) string {
				if v1 == nil || v2 == nil {
					return ""
				}
				if v1 == v2 {
					return "selected"
				}
				return ""
			},
			// Form result helpers
			"q": func(v interface{}) string {
				if v == nil || v.(string) == "" {
					return "<output class=none>none</output>"
				}
				return "<output><q>" + template.HTMLEscapeString(v.(string)) + "</q></output>"
			},
			"have": func(v interface{}) bool {
				return v != nil && v.(string) == "on"
			},
			"date": func(v string) string {
				t, err := time.Parse("2006-01-02", v)
				if err != nil {
					panic(err)
				}
				return t.Format("January 2, 2006")
			},
		}).
		ParseFiles(filenames...))
}