examples/html: Read from stdin and write to stdout

examples/html.go

@@ -7,76 +7,77 @@ package main
 import (
 	"fmt"
 	"html"
-	"strings"
+	"io"
+	"os"
 
 	"git.sr.ht/~adnano/go-gemini"
 )
 
 func main() {
-	text := gemini.Text{
+	hw := HTMLWriter{
-		gemini.LineHeading1("Hello, world!"),
+		out: os.Stdout,
-		gemini.LineText("This is a gemini text document."),
 	}
-
+	gemini.ParseLines(os.Stdin, hw.Handle)
-	html := textToHTML(text)
+	hw.Finish()
-	fmt.Print(html)
 }
 
-// textToHTML returns the Gemini text response as HTML.
+type HTMLWriter struct {
-func textToHTML(text gemini.Text) string {
+	out  io.Writer
-	var b strings.Builder
+	pre  bool
-	var pre bool
+	list bool
-	var list bool
+}
-	for _, l := range text {
+
-		if _, ok := l.(gemini.LineListItem); ok {
+func (h *HTMLWriter) Handle(line gemini.Line) {
-			if !list {
+	if _, ok := line.(gemini.LineListItem); ok {
-				list = true
+		if !h.list {
-				fmt.Fprint(&b, "<ul>\n")
+			h.list = true
-			}
+			fmt.Fprint(h.out, "<ul>\n")
-		} else if list {
-			list = false
-			fmt.Fprint(&b, "</ul>\n")
 		}
-		switch l := l.(type) {
+	} else if h.list {
-		case gemini.LineLink:
+		h.list = false
-			url := html.EscapeString(l.URL)
+		fmt.Fprint(h.out, "</ul>\n")
-			name := html.EscapeString(l.Name)
+	}
-			if name == "" {
+	switch line := line.(type) {
-				name = url
+	case gemini.LineLink:
-			}
+		url := html.EscapeString(line.URL)
-			fmt.Fprintf(&b, "<p><a href='%s'>%s</a></p>\n", url, name)
+		name := html.EscapeString(line.Name)
-		case gemini.LinePreformattingToggle:
+		if name == "" {
-			pre = !pre
+			name = url
-			if pre {
+		}
-				fmt.Fprint(&b, "<pre>\n")
+		fmt.Fprintf(h.out, "<p><a href='%s'>%s</a></p>\n", url, name)
-			} else {
+	case gemini.LinePreformattingToggle:
-				fmt.Fprint(&b, "</pre>\n")
+		h.pre = !h.pre
-			}
+		if h.pre {
-		case gemini.LinePreformattedText:
+			fmt.Fprint(h.out, "<pre>\n")
-			fmt.Fprintf(&b, "%s\n", html.EscapeString(string(l)))
+		} else {
-		case gemini.LineHeading1:
+			fmt.Fprint(h.out, "</pre>\n")
-			fmt.Fprintf(&b, "<h1>%s</h1>\n", html.EscapeString(string(l)))
+		}
-		case gemini.LineHeading2:
+	case gemini.LinePreformattedText:
-			fmt.Fprintf(&b, "<h2>%s</h2>\n", html.EscapeString(string(l)))
+		fmt.Fprintf(h.out, "%s\n", html.EscapeString(string(line)))
-		case gemini.LineHeading3:
+	case gemini.LineHeading1:
-			fmt.Fprintf(&b, "<h3>%s</h3>\n", html.EscapeString(string(l)))
+		fmt.Fprintf(h.out, "<h1>%s</h1>\n", html.EscapeString(string(line)))
-		case gemini.LineListItem:
+	case gemini.LineHeading2:
-			fmt.Fprintf(&b, "<li>%s</li>\n", html.EscapeString(string(l)))
+		fmt.Fprintf(h.out, "<h2>%s</h2>\n", html.EscapeString(string(line)))
-		case gemini.LineQuote:
+	case gemini.LineHeading3:
-			fmt.Fprintf(&b, "<blockquote>%s</blockquote>\n", html.EscapeString(string(l)))
+		fmt.Fprintf(h.out, "<h3>%s</h3>\n", html.EscapeString(string(line)))
-		case gemini.LineText:
+	case gemini.LineListItem:
-			if l == "" {
+		fmt.Fprintf(h.out, "<li>%s</li>\n", html.EscapeString(string(line)))
-				fmt.Fprint(&b, "<br>\n")
+	case gemini.LineQuote:
-			} else {
+		fmt.Fprintf(h.out, "<blockquote>%s</blockquote>\n", html.EscapeString(string(line)))
-				fmt.Fprintf(&b, "<p>%s</p>\n", html.EscapeString(string(l)))
+	case gemini.LineText:
-			}
+		if line == "" {
+			fmt.Fprint(h.out, "<br>\n")
+		} else {
+			fmt.Fprintf(h.out, "<p>%s</p>\n", html.EscapeString(string(line)))
 		}
 	}
-	if pre {
+}
-		fmt.Fprint(&b, "</pre>\n")
+
+func (h *HTMLWriter) Finish() {
+	if h.pre {
+		fmt.Fprint(h.out, "</pre>\n")
 	}
-	if list {
+	if h.list {
-		fmt.Fprint(&b, "</ul>\n")
+		fmt.Fprint(h.out, "</ul>\n")
 	}
-	return b.String()
 }