package main

import (
	"errors"
	"fmt"
	"io"
	"io/fs"
	"log"
	"net"
	"os"
	"path/filepath"
)

func main() {
	var cmd string
	switch len(os.Args) {
	case 2:
		cmd = os.Args[1]
	case 3:
		cmd = os.Args[2]
	default:
		fmt.Println("send a raw message to bndd.")
		fmt.Println("usage: [instance-path] <command>.")
		fmt.Println("note: quotes must be escaped.")
		fmt.Println("note: this program should not be executed from the shell. Use a CLI wrapper instead.")
		os.Exit(1)
	}
	instance_path, err := get_instance_path()
	if err != nil {
		log.Fatal(err)
	}
	ln, err := net.Dial("unix", instance_path+"/boundaries.sock")
	if err != nil {
		log.Fatal(err)
	}
	ln.Write([]byte(cmd))
	go func() {
		for {
			buffer := make([]byte, 1024)
			n, err := os.Stdin.Read(buffer)
			if err == io.EOF {
				break
			} else if err != nil {
				log.Fatal(err)
			}
			ln.Write(buffer[:n])
		}
	}()
	func() {
		for {
			buffer := make([]byte, 1024)
			n, err := ln.Read(buffer)
			if err == io.EOF {
				break
			} else if err != nil {
				log.Fatal(err)
			}
			os.Stdout.Write(buffer[:n])
		}
	}()
}

func path_exists(path string) (bool, error) {
	_, err := os.Stat(path)
	if err == nil {
		return true, nil
	}
	if errors.Is(err, fs.ErrNotExist) {
		return false, nil
	}
	return false, err
}

func get_instance_path() (string, error) {
	if len(os.Args) == 3 {
		return filepath.Abs(os.Args[1])
	}

	// When send-command has been started by boundaries, this can be used to get the instance it used
	app_dir, has := os.LookupEnv("APP_DIR")
	if has {
		return filepath.Abs(filepath.Join(app_dir, "..", ".."))
	}

	// Fallback to the user-path
	home, err := os.UserHomeDir()
	if err != nil {
		return "", err
	}
	home_instance_path, err := filepath.Abs(filepath.Join(home, "boundaries"))
	if exists, err := path_exists(home_instance_path); exists && err == nil {
		return home_instance_path, nil
	}

	return "", errors.New("no suitable instance path found")
}