package handlers

import (
	"html/template"
	"path/filepath"
)

// NewTemplateCache parses every page template once, each paired with the
// shared layout, and returns them keyed by page filename (e.g. "index.tmpl").
// Handlers look up the pre-parsed template instead of re-parsing files on
// every request.
func NewTemplateCache() (map[string]*template.Template, error) {
	cache := map[string]*template.Template{}

	pages, err := filepath.Glob("./ui/html/pages/*.tmpl")
	if err != nil {
		return nil, err
	}

	for _, page := range pages {
		name := filepath.Base(page)

		files := []string{
			"./ui/html/base.tmpl",
			"./ui/html/navbar.tmpl",
			page,
		}

		ts, err := template.ParseFiles(files...)
		if err != nil {
			return nil, err
		}

		cache[name] = ts
	}

	return cache, nil
}