pgenr/element/element.go

package element

import (
	"git.nspix.com/golang/pgenr/internal/pool"
	"golang.org/x/net/html/atom"
	"html"
	"strconv"
	"strings"
)

type (
	Option func(t *element)

	Element interface {
		Html() string
	}

	Attrs map[string]string

	element struct {
		Name    atom.Atom
		Attr    Attrs
		Content string
	}
)

func renderTag(tag string, attrs Attrs, content string) string {
	br := pool.Get()
	defer pool.Put(br)
	br.WriteString("<" + tag)
	if len(attrs) > 0 {
		for k, v := range attrs {
			if !strings.HasPrefix(k, "data-") {
				if atom.Lookup([]byte(k)) == 0 {
					continue
				}
			}
			br.WriteString(" " + k + "=" + strconv.Quote(v))
		}
	}
	br.WriteString(">")
	br.WriteString(content)
	br.WriteString("</" + tag + ">")
	return br.String()
}

func beginTag(tag string, attrs Attrs) string {
	br := pool.Get()
	defer pool.Put(br)
	br.WriteString("<" + tag)
	if len(attrs) > 0 {
		for k, v := range attrs {
			if atom.Lookup([]byte(k)) == 0 {
				continue
			}
			br.WriteString(" " + k + "=\"" + v + "\" ")
		}
	}
	br.WriteString(">")
	return br.String()
}

func endTag(tag string) string {
	br := pool.Get()
	defer pool.Put(br)
	br.WriteString("</" + tag + ">")
	return br.String()
}

func WithAttribute(label string, value string) Option {

	return func(t *element) {
		if t.Attr == nil {
			t.Attr = make(map[string]string)
		}
		t.Attr[label] = value
	}
}

func (element *element) Html() string {
	return element.String()
}

func (element *element) String() string {
	return renderTag(element.Name.String(), element.Attr, html.EscapeString(element.Content))
}

func NewElement(atom atom.Atom, content string, opts ...Option) *element {
	e := &element{Name: atom, Content: content}
	for _, cb := range opts {
		cb(e)
	}
	return e
}