package linux

import (
	"errors"
	"fmt"
	"os"
	"os/exec"
)

func NewCommand(options CommandOptions) (*LinuxCommand, error) {

	if len(options.Shell) == 0 {
		options.Shell = "/bin/bash"
	}

	if len(options.Cwd) == 0 {
		cwd, err := os.Getwd()
		if err != nil {
			return nil, ErrFetchingCwd
		}
		options.Cwd = cwd
	}

	return &LinuxCommand{
		Options: options,
	}, nil

}

func (cmd *LinuxCommand) Run() error {

	var sourceCommand string
	for _, value := range cmd.Options.Sources {
		sourceCommand += fmt.Sprintf("source %s && ", value)
	}

	command := exec.Command(cmd.Options.Shell, "-c", sourceCommand+cmd.Options.Command)
	command.Dir = cmd.Options.Cwd
	command.Args = append(command.Args, cmd.Options.Args...)

	// Loop through env to format and add them to the command.
	for key, value := range cmd.Options.Env {
		command.Env = append(command.Env, fmt.Sprintf("%s=%s", key, value))
	}

	isCommandExecutable, err := cmd.isCommandExecutable(cmd.Options.Command)
	if err != nil {
		return err
	}

	if !isCommandExecutable {
		return ErrCommandNotExecutable
	}

	if err := command.Start(); err != nil {
		var exitErr *exec.ExitError
		if errors.As(err, &exitErr) {
			fmt.Println(exitErr.ExitCode())
			if exitErr.ExitCode() == 127 {
				return ErrCommandNotFound
			} else {
				return fmt.Errorf("%s: %w", ErrRunningCmd.Error(), err)
			}
		}
	}

	if err := command.Wait(); err != nil {
		var exitErr *exec.ExitError
		if errors.As(err, &exitErr) {
			fmt.Println(exitErr.ExitCode())
			if exitErr.ExitCode() == 127 {
				return ErrCommandNotFound
			} else {
				return fmt.Errorf("%s: %w", ErrRunningCmd.Error(), err)
			}
		}
	}

	return nil

}