Created

htmlx/html.go

@@ -0,0 +1,186 @@
+package htmlx
+
+import (
+	"regexp"
+	"sort"
+	"strings"
+	"unicode/utf8"
+
+	"git.cloudyne.io/go/hiscaler-gox/stringx"
+)
+
+var (
+	// Strip regexp
+	rxStrip = regexp.MustCompile(`(?s)<sty(.*)/style>|<scr(.*)/script>|<link(.*)/>|<meta(.*)/>|<!--(.*)-->| style=['"]+(.*)['"]+`)
+
+	// Spaceless regexp
+	rxSpaceless = regexp.MustCompile(`/>\s+</`)
+
+	// Clean regexp
+	rxCleanCSS        = regexp.MustCompile(`(?s)<sty(.*)/style>|<link(.*)/>| style=['"]+(.*)['"]+`)
+	rxCleanJavascript = regexp.MustCompile(`(?s)<script(.*)/script>`)
+	rxCleanComment    = regexp.MustCompile(`(?s)<!--(.*)-->`)
+	rxCleanMeta       = regexp.MustCompile(`(?s)<meta(.*)/>`)
+)
+
+type CleanMode uint32
+
+const (
+	CleanModeCSS CleanMode = 1 << (10 - iota) // 包括元素内嵌样式
+	CleanModeJavascript
+	CleanModeComment
+	CleanModeMeta
+	CleanModeSpace
+	CleanModeAll = CleanModeCSS | CleanModeJavascript | CleanModeComment | CleanModeMeta | CleanModeSpace
+)
+
+// Strip Clean html tags
+// https://stackoverflow.com/questions/55036156/how-to-replace-all-html-tag-with-empty-string-in-golang
+func Strip(html string) string {
+	html = strings.TrimSpace(html)
+	if html != "" {
+		html = rxStrip.ReplaceAllString(html, "")
+	}
+	if html == "" {
+		return ""
+	}
+
+	const (
+		htmlTagStart = 60 // Unicode `<`
+		htmlTagEnd   = 62 // Unicode `>`
+	)
+	// Setup a string builder and allocate enough memory for the new string.
+	var builder strings.Builder
+	builder.Grow(len(html) + utf8.UTFMax)
+
+	in := false // True if we are inside an HTML tag.
+	start := 0  // The index of the previous start tag character `<`
+	end := 0    // The index of the previous end tag character `>`
+
+	for i, c := range html {
+		// If this is the last character and we are not in an HTML tag, save it.
+		if (i+1) == len(html) && end >= start && c != htmlTagStart && c != htmlTagEnd {
+			builder.WriteString(html[end:])
+		}
+
+		// Keep going if the character is not `<` or `>`
+		if c != htmlTagStart && c != htmlTagEnd {
+			continue
+		}
+
+		if c == htmlTagStart {
+			// Only update the start if we are not in a tag.
+			// This make sure we strip out `<<br>` not just `<br>`
+			if !in {
+				start = i
+			}
+			in = true
+
+			// Write the valid string between the close and start of the two tags.
+			builder.WriteString(html[end:start])
+			continue
+		}
+		// else c == htmlTagEnd
+		in = false
+		end = i + 1
+	}
+	s := builder.String()
+	if s != "" {
+		s = strings.TrimSpace(Spaceless(s))
+	}
+	return s
+}
+
+// Spaceless 移除多余的空格
+func Spaceless(html string) string {
+	html = stringx.RemoveExtraSpace(html)
+	if html == "" {
+		return ""
+	}
+
+	return rxSpaceless.ReplaceAllString(html, "><")
+}
+
+func Clean(html string, cleanMode CleanMode) string {
+	if html == "" {
+		return html
+	}
+	const n = 5
+	modes := [n]bool{} // css, javascript, comment, meta, space, all
+	for i := 0; i < n; i++ {
+		if cleanMode&(1<<uint(10-i)) != 0 {
+			modes[i] = true
+		}
+	}
+	if modes[n-1] {
+		html = Spaceless(rxStrip.ReplaceAllString(html, ""))
+	} else {
+		for i := 0; i < n-2; i++ {
+			if modes[i] {
+				switch i {
+				case 0:
+					html = rxCleanCSS.ReplaceAllString(html, "")
+				case 1:
+					html = rxCleanJavascript.ReplaceAllString(html, "")
+				case 2:
+					html = rxCleanComment.ReplaceAllString(html, "")
+				case 3:
+					html = rxCleanMeta.ReplaceAllString(html, "")
+				case 4:
+					html = Spaceless(html)
+				}
+			}
+		}
+	}
+	return html
+}
+
+func Tag(tag, content string, attributes, styles map[string]string) string {
+	var sb strings.Builder
+	sb.Grow(len(tag)*2 + len(content) + 5)
+	sb.WriteString("<")
+	sb.WriteString(tag)
+	fnSortedKeys := func(d map[string]string) []string {
+		n := len(d)
+		if n == 0 {
+			return nil
+		}
+
+		keys := make([]string, n)
+		i := 0
+		for k := range d {
+			keys[i] = k
+			i++
+		}
+		if i > 1 {
+			sort.Strings(keys)
+		}
+		return keys
+	}
+
+	for _, k := range fnSortedKeys(attributes) {
+		sb.WriteString(" ")
+		sb.WriteString(k)
+		sb.WriteString(`="`)
+		sb.WriteString(attributes[k])
+		sb.WriteString(`"`)
+	}
+
+	keys := fnSortedKeys(styles)
+	if len(keys) > 0 {
+		sb.WriteString(` style="`)
+		for _, k := range keys {
+			sb.WriteString(k)
+			sb.WriteString(":")
+			sb.WriteString(styles[k])
+			sb.WriteString(`;`)
+		}
+		sb.WriteString(`"`)
+	}
+	sb.WriteString(">")
+	sb.WriteString(content)
+	sb.WriteString("</")
+	sb.WriteString(tag)
+	sb.WriteString(">")
+	return sb.String()
+}