/*
 * Micro Service
 * Package: gitlab.hexacode.org/go-libs/microservice
 * Maintainer: Azzis Arswendo <azzis@hexacode.org>
 *
 * Copyright (C) 2023 Hexacode Teknologi Indonesia
 * All Rights Reserved
 */

// Example from string:
// tmpl, err := config.NewTemplate("Hello {{ name }}")
//
// Example from file:
// tmpl, err := config.NewTemplateFromFile("template.html")
//
// Example Render:
// render, err := tmpl.Render(hctypes.Dict{"name": "John Doe"})
// Please see https://github.com/noirbizarre/gonja for more details template

package config

import (
	"encoding/json"
	"os"

	"github.com/noirbizarre/gonja"
	"github.com/noirbizarre/gonja/exec"
	"gitlab.hexacode.org/go-libs/hctypes"
)

// Template represents a mail template
type Template struct {
	template *exec.Template // The template instance
}

// NewTemplate creates a new Template
//
// template: The template
// Returns: *Template
func NewTemplate(template string) (*Template, error) {
	tmpl, err := gonja.FromString(template)
	return &Template{
		template: tmpl,
	}, err
}

// NewTeplateFromFile creates a new Template
//
// template_file: The template file
// Returns: *Template
func NewTemplateFromFile(template_file string) (*Template, error) {
	data, err := os.ReadFile(template_file)
	if err != nil {
		return nil, err
	}

	tmpl, err := gonja.FromBytes(data)
	return &Template{
		template: tmpl,
	}, err
}

// Render renders the template
//
// data: The data
// Returns: string
func (t *Template) Render(data hctypes.Dict) (string, error) {
	raw := map[string]interface{}{}
	err := json.Unmarshal([]byte(data.ToJson()), &raw)
	if err != nil {
		return "", err
	}
	return t.template.Execute(raw)
}