package cmds

import (
	"errors"
	"fmt"
	"os"
	"strings"

	"gosh/global"
)

// printEnv: prints all environment variables with shell options.
func PrintEnv() {
	vars := os.Environ()
	for i := range vars {
		fmt.Println(vars[i])
	}
	if len(global.Options) > 0 {
		fmt.Printf("SH_OPTS=%v\n", global.Options)
	}
}

// set: sets the shell options
func Set(args []string) {
	for i := 1; i < len(args); i++ {
		if i-1 >= len(global.Options) {
			global.Options = append(global.Options, args[i])
			continue
		}
		global.Options[i-1] = args[i]
	}

	if len(args)-1 < len(global.Options) {
		global.Options = global.Options[:len(args)-1]
	}
}

// unset: unsets an environment variable
func Unset(args []string) error {
	if len(args) == 1 || len(args) >= 3 {
		return errors.New("usage: unset [name]")
	}
	os.Unsetenv(args[1])
	return nil
}

// export: exports a key-value pair to the environment
// in the form of `name=value`
func Export(args []string) error {
	if len(args) == 1 || len(args) >= 3 {
		return errors.New("usage: export [name=value]")
	}
	tmp := strings.Split(args[1], "=")
	if len(tmp) != 2 {
		return errors.New("usage: export [name=value]")
	}
	return os.Setenv(tmp[0], tmp[1])
}