html2gmi/html2gmi.go
2020-08-13 12:38:23 +01:00

108 lines
2.2 KiB
Go

package main
import (
"bufio"
"errors"
"fmt"
"github.com/LukeEmmet/html2gemini"
flag "github.com/spf13/pflag"
"io"
"io/ioutil"
"os"
)
var version = "0.2.1"
var (
output = flag.StringP("output", "o", "", "Output path. Otherwise uses stdout\n")
input = flag.StringP("input", "i", "", "Input path. Otherwise uses stdin\n")
citationStart = flag.IntP("citationStart", "c", 1, "Start citations from this index")
linkEmitFrequency = flag.IntP("linkEmitFrequency", "l", 2, "Emit gathered links through the document after this number of paragraphs")
verFlag = flag.BoolP("version", "v", false, "Find out what version of html2gmi you're running")
)
func check(e error) {
if e != nil {
panic(e)
}
}
func saveFile(contents []byte, path string) {
d1 := contents
err := ioutil.WriteFile(path, d1, 0644)
check(err)
}
func readStdin() string {
// based on https://flaviocopes.com/go-shell-pipes/
reader := bufio.NewReader(os.Stdin) //default size is 4096 apparently
var output []rune
for {
input, _, err := reader.ReadRune()
if err != nil && err == io.EOF {
break
}
output = append(output, input)
}
return string(output)
}
func getInput() (string, error) {
var inputHtml string
info, err := os.Stdin.Stat()
check(err)
if info.Mode()&os.ModeNamedPipe != 0 {
// we have a pipe input
inputHtml = readStdin()
} else if *input != "" {
//get the input file from the command line
dat, err := ioutil.ReadFile(*input)
check(err)
inputHtml = string(dat)
} else {
//we shouldn't get here
return "", errors.New("invalid option for input - use -i <path> or pipe to stdin")
}
return inputHtml, nil
}
func main() {
var inputHtml string
flag.Parse()
if *verFlag {
fmt.Println("html2gmi " + version)
return
}
//get the input from commandline or stdin
inputHtml, err := getInput()
check(err)
//convert html to gmi
options := html2gemini.NewOptions()
options.PrettyTables = true
options.CitationStart = *citationStart
options.LinkEmitFrequency = *linkEmitFrequency
text, err := html2gemini.FromString(inputHtml, *options)
check(err)
//process the output
if *output == "" {
fmt.Print(text)
} else {
//save to the specified output
gmiBytes := []byte(text)
saveFile(gmiBytes, *output)
}
}