konbata/perrors.go

package main

import (
	"os"
	"bufio"
	"strconv"
	"strings"
	"net/url"
	"path/filepath"

	"git.sr.ht/~adnano/go-gemini"
)

var perrors map[string]PError

type PError struct {
	Code    gemini.Status
	Message string
}

func populatePErrors() error {
	file, err := os.OpenFile(filepath.Join(xdgDataHome(), "konbata", "perrors"), os.O_RDONLY|os.O_CREATE, 0600)
	if err != nil {
		return err
	}
	defer file.Close()
	scanner := bufio.NewScanner(file)
	perrors = make(map[string]PError)
	unescaper := strings.NewReplacer("\\n", "\n", "\\\\", "\\")
	for scanner.Scan() {
		values := strings.SplitN(scanner.Text(), " ", 3)
		if len(values) != 3 {
			continue
		}
		url, err := url.Parse(values[0])
		if err != nil {
			continue
		}
		if url.Scheme != "gemini" {
			continue
		}
		code, err := strconv.Atoi(values[1])
		if err != nil {
			continue
		}
		perrors[url.String()] = PError{
			Code: gemini.Status(code),
			Message: unescaper.Replace(values[2]),
		}
	}
	return nil
}

func savePErrors() error {
	file, err := os.OpenFile(filepath.Join(xdgDataHome(), "konbata", "perrors"), os.O_WRONLY|os.O_CREATE, 0600)
	if err != nil {
		return err
	}
	defer file.Close()
	err = file.Truncate(0)
	if err != nil {
		return err
	}
	writer := bufio.NewWriter(file)
	escaper := strings.NewReplacer("\\", "\\\\", "\n", "\\n")
	for url, perror := range perrors {
		_, err = writer.WriteString(url)
		if err != nil {
			return err
		}
		_, err = writer.WriteRune(' ')
		if err != nil {
			return err
		}
		_, err = writer.WriteString(strconv.Itoa(int(perror.Code)))
		if err != nil {
			return err
		}
		_, err = writer.WriteRune(' ')
		if err != nil {
			return err
		}
		_, err = escaper.WriteString(writer, perror.Message)
		if err != nil {
			return err
		}
		_, err = writer.WriteRune('\n')
		if err != nil {
			return err
		}
	}
	return writer.Flush()
}