package template

import (
	"embed"
	"errors"
	"fmt"
	"html/template"
	"io/fs"

	"code.capytal.cc/loreddev/x/xtemplate"
)

func New() (xtemplate.Template, error) {
	return xtemplate.New[template.Template]("template").
		Funcs(functions).
		ParseFS(embedded, patterns...)
}

//go:embed *.html layouts/*.html
var embedded embed.FS

func Dev(dir fs.FS) (xtemplate.Template, error) {
	return xtemplate.NewHot[template.Template]("template").
		Funcs(functions).
		ParseFS(dir, patterns...)
}

var (
	patterns  = []string{"*.html", "layouts/*.html"}
	functions = template.FuncMap{
		"args": func(pairs ...any) (map[string]any, error) {
			if len(pairs)%2 != 0 {
				return nil, errors.New("misaligned map in template arguments")
			}

			m := make(map[string]any, len(pairs)/2)

			for i := 0; i < len(pairs); i += 2 {
				key, ok := pairs[i].(string)
				if !ok {
					return nil, fmt.Errorf("cannot use type %T as map key", pairs[i])
				}

				m[key] = pairs[i+1]
			}

			return m, nil
		},
	}
)