um/next/next.go

115 lines
3 KiB
Go

package next
import (
"errors"
"fmt"
"log"
"os/exec"
"regexp"
"strconv"
"github.com/brtholomy/um/go/cmd"
"github.com/brtholomy/um/go/flags"
"github.com/brtholomy/um/go/last"
)
const (
CMD = cmd.Next
SUMMARY = "create the next um file and open with emacsclient"
)
const FILE_REGEXP = `(?m)^([0-9]+)\.[[:alpha:]]*\.*md$`
var fileRegexp *regexp.Regexp = regexp.MustCompile(FILE_REGEXP)
type options struct {
Descriptor flags.Arg
Tags flags.Arg
Help flags.Bool
}
func initOpts() options {
return options{
flags.Arg{"", "midfix file descriptor"},
flags.Arg{"", "tags to add to new file"},
flags.Bool{"--help", "-h", false, "show help"},
}
}
// takes the complete last file string
// returns the number as string
func NumFromLast(l string) (string, error) {
res := fileRegexp.FindStringSubmatch(l)
num := ""
if len(res) < 2 {
return num, errors.New(last.NOT_FOUND_MSG)
}
num = res[1]
return num, nil
}
// takes the complete last file string and new descriptor
// returns the complete next file string
func next(last string, desc string) (string, error) {
num, err := NumFromLast(last)
if err != nil {
return "", err
}
i, err := strconv.Atoi(num)
if err != nil {
return "", err
}
if desc != "" {
desc = desc + "."
}
width := len(num)
// whaddya doin bro wahh
fmtstr := fmt.Sprintf("%%0%dd.%%smd", width)
n := fmt.Sprintf(fmtstr, i+1, desc)
return n, nil
}
// calls (um-next) inside a running emacs server. which has the advantage of fetching the loaded
// value of um-date-format, and respecting any other loaded configuration we might add.
//
// other options would be to forego respecting Elisp config values, or loading from a common config
// file and forcing emacs to load from there - which would be very un-Emacs. But as the file loading
// assumes a running server anyway, might as well get the current values.
//
// this is the point at which this design becomes weird. But I don't want to let Elisp suck this CLI
// into its nasty grip. Go is far superior in this application and there's no way I'm writing the
// `um tag` logic in Elisp.
//
// So I've got Go and and an ancient beloved Lisp machine trying to live together.
func emacsNext(f string, tags string) error {
quotedargs := fmt.Sprintf(`"%s"`, f)
if tags != "" {
quotedargs = fmt.Sprintf(`%s "%s"`, quotedargs, tags)
}
fn := fmt.Sprintf(`(um-next %s)`, quotedargs)
out, err := exec.Command("emacsclient", "--eval", fn).CombinedOutput()
if err != nil {
return err
}
// NOTE: sends to stderr : is this what we want?
// if we decide to pipe the filename out, yes.
log.Print(string(out))
return nil
}
func Next(args []string) {
opts := initOpts()
flags.ParseArgs(CMD, SUMMARY, args, &opts)
l, err := last.GlobLast(last.GLOB)
if err != nil {
log.Fatalf("um %s: %v", CMD, err)
}
filename, err := next(l, opts.Descriptor.Val)
if err != nil {
log.Fatalf("um %s: %v", CMD, err)
}
if err := emacsNext(filename, opts.Tags.Val); err != nil {
log.Fatalf("um %s: %v", CMD, err)
}
}