package cli

import (
	"flag"
	"fmt"
	"io"
	"os"
	"strings"

	"gitea.pglikers.com/tools/slacksend/internal/version"
)

type Options struct {
	ShowVersion bool
}

func Run(args []string) int {
	return run(args, os.Stdin, os.Stdout, os.Stderr)
}

func run(args []string, stdin io.Reader, stdout, stderr io.Writer) int {
	fs := flag.NewFlagSet("slacksend", flag.ContinueOnError)
	fs.SetOutput(stderr)
	fs.Usage = func() { Usage(stdout) }

	var opt Options
	fs.BoolVar(&opt.ShowVersion, "version", false, "show version")
	fs.BoolVar(&opt.ShowVersion, "V", false, "show version (short)")

	if err := fs.Parse(args[1:]); err != nil {
		if err == flag.ErrHelp {
			Usage(stdout)
			return 0
		}
		fmt.Fprintln(stderr, err)
		Usage(stderr)
		return 2
	}

	if opt.ShowVersion {
		fmt.Fprintln(stdout, version.String())
		return 0
	}

	msg, err := message(fs.Args(), stdin)
	if err != nil {
		fmt.Fprintln(stderr, "read message error:", err)
		return 1
	}
	if msg == "" {
		Usage(stderr)
		return 2
	}

	// TODO: Slack送信（ここはあとで internal/slack に逃がす）
	fmt.Fprintln(stdout, msg)
	return 0
}

func message(args []string, stdin io.Reader) (string, error) {
	if len(args) > 0 {
		return strings.Join(args, " "), nil
	}
	b, err := io.ReadAll(stdin)
	if err != nil {
		return "", err
	}
	return strings.TrimSpace(string(b)), nil
}