add gemini

1 files changed, 132 insertions, 0 deletions

diff --git a/bin/gemini b/bin/gemini
new file mode 100755
index 0000000..1bc3d57
--- /dev/null
+++ b/bin/gemini
@@ -0,0 +1,132 @@
+#!/usr/bin/env yaegi
+package main
+
+import (
+	"bufio"
+	"crypto/tls"
+	"fmt"
+	"io/ioutil"
+	"net/url"
+	"os"
+	"strconv"
+	"strings"
+)
+
+func main() {
+	stdinReader := bufio.NewReader(os.Stdin)
+	var u string // URL
+	links := make([]string, 0, 100)
+	history := make([]string, 0, 100)
+	for {
+		fmt.Print("> ")
+		cmd, _ := stdinReader.ReadString('\n')
+		cmd = strings.TrimSpace(cmd)
+		// Command dispatch
+		switch strings.ToLower(cmd) {
+		case "": // Nothing
+			continue
+		case "q": // Quit
+			fmt.Println("Bye!")
+			os.Exit(0)
+		case "b": // Back
+			if len(history) < 2 {
+				fmt.Println("No history yet!")
+				continue
+			}
+			u = history[len(history)-2]
+			history = history[0 : len(history)-2]
+		default:
+			index, err := strconv.Atoi(cmd)
+			if err != nil {
+				// Treat this as a URL
+				u = cmd
+				if !strings.HasPrefix(u, "gemini://") {
+					u = "gemini://" + u
+				}
+			} else {
+				// Treat this as a menu lookup
+				u = links[index-1]
+			}
+		}
+		// Parse URL
+		parsed, err := url.Parse(u)
+		if err != nil {
+			fmt.Println("Error parsing URL!")
+			continue
+		}
+		// Connect to server
+		conn, err := tls.Dial("tcp", parsed.Host+":1965", &tls.Config{InsecureSkipVerify: true})
+		if err != nil {
+			fmt.Println("Failed to connect: " + err.Error())
+			continue
+		}
+		defer conn.Close()
+		// Send request
+		conn.Write([]byte(u + "\r\n"))
+		// Receive and parse response header
+		reader := bufio.NewReader(conn)
+		responseHeader, err := reader.ReadString('\n')
+		parts := strings.Fields(responseHeader)
+		status, err := strconv.Atoi(parts[0][0:1])
+		meta := parts[1]
+		// Switch on status code
+		switch status {
+		case 1, 3, 6:
+			// No input, redirects or client certs
+			fmt.Println("Unsupported feature!")
+		case 2:
+			// Successful transaction
+			// text/* content only
+			if !strings.HasPrefix(meta, "text/") {
+				fmt.Println("Unsupported type " + meta)
+				continue
+			}
+			// Read everything
+			bodyBytes, err := ioutil.ReadAll(reader)
+			if err != nil {
+				fmt.Println("Error reading body")
+				continue
+			}
+			body := string(bodyBytes)
+			if meta == "text/gemini" {
+				// Handle Gemini map
+				links = make([]string, 0, 100)
+				preformatted := false
+				for _, line := range strings.Split(body, "\n") {
+					if strings.HasPrefix(line, "```") {
+						preformatted = !preformatted
+					} else if preformatted {
+						fmt.Println(line)
+					} else if strings.HasPrefix(line, "=>") {
+						line = line[2:]
+						bits := strings.Fields(line)
+						parsedLink, err := url.Parse(bits[0])
+						if err != nil {
+							continue
+						}
+						link := parsed.ResolveReference(parsedLink).String()
+						var label string
+						if len(bits) == 1 {
+							label = link
+						} else {
+							label = strings.Join(bits[1:], " ")
+						}
+						links = append(links, link)
+						fmt.Printf("[%d] %s\n", len(links), label)
+					} else {
+						// This should really be wrapped, but there's
+						// no easy support for this in Go's standard
+						// library
+						fmt.Println(line)
+					}
+				}
+			} else {
+				// Just print any other kind of text
+				fmt.Print(body)
+			}
+			history = append(history, u)
+		case 4, 5:
+			fmt.Println("ERROR: " + meta)
+		}
+	}
+}