templates.go

// Copyright (C) 2024 The Dagu Authors
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.

package server

import (
	"bytes"
	"io"
	"net/http"
	"path/filepath"
	"text/template"

	"github.com/dagu-org/dagu/internal/constants"
)

var (
	// templatePath is the path to the templates directory.
	templatePath = "templates/"
)

func (srv *Server) useTemplate(
	layout string, name string,
) func(http.ResponseWriter, any) {
	files := append(baseTemplates(), filepath.Join(templatePath, layout))
	tmpl, err := template.New(name).Funcs(
		defaultFunctions(srv.funcsConfig)).ParseFS(srv.assets, files...,
	)
	if err != nil {
		panic(err)
	}

	return func(w http.ResponseWriter, data any) {
		var buf bytes.Buffer
		if err := tmpl.ExecuteTemplate(&buf, "base", data); err != nil {
			srv.logger.Error("Template execution failed", "error", err)
			http.Error(w, err.Error(), http.StatusInternalServerError)
			return
		}
		w.WriteHeader(http.StatusOK)
		_, _ = io.Copy(w, &buf)
	}
}

type funcsConfig struct {
	NavbarColor string
	NavbarTitle string
	APIBaseURL  string
}

func defaultFunctions(cfg funcsConfig) template.FuncMap {
	return template.FuncMap{
		"defTitle": func(ip any) string {
			v, ok := ip.(string)
			if !ok || (ok && v == "") {
				return ""
			}
			return v
		},
		"version": func() string {
			return constants.Version
		},
		"navbarColor": func() string {
			return cfg.NavbarColor
		},
		"navbarTitle": func() string {
			return cfg.NavbarTitle
		},
		"apiURL": func() string {
			return cfg.APIBaseURL
		},
	}
}

func baseTemplates() []string {
	var templateFiles = []string{"base.gohtml"}
	ret := make([]string, 0, len(templateFiles))
	for _, t := range templateFiles {
		ret = append(ret, filepath.Join(templatePath, t))
	}
	return ret
}