package cmd

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

	"github.com/spf13/cobra"
)

func newCbc2cCmd() *cobra.Command {
	cmd := &cobra.Command{
		Use:   "cbc2c [file]",
		Short: "dump path the converted C file of CbC.",
		Args:  cobra.ExactArgs(1),
		RunE:  cbc2c,
	}
	cmd.AddCommand(newCbc2cEditorCmd())
	return cmd
}

func cbc2c(cmd *cobra.Command, args []string) error {
	cfile, err := cbcfile2cfilepath(args[0])
	if err != nil {
		return fmt.Errorf("failed cbc2c command %v", err)
	}
	fmt.Fprintln(cmd.OutOrStdout(), cfile)
	return nil
}

func cbcfile2cfilepath(arg string) (string, error) {
	cbcfilePath := arg

	if !fileExists(cbcfilePath) {
		return "", errors.New("failed nout found files")
	}
	var idx int
	if idx = strings.LastIndex(cbcfilePath, ".cbc"); idx == -1 {
		return "", errors.New("failed nout found cbc files")
	}

	var b strings.Builder
	b.Grow(32)
	b.WriteString("c/")
	b.WriteString(cbcfilePath[0:idx])
	b.WriteString(".c")
	return b.String(), nil
}

func newCbc2cEditorCmd() *cobra.Command {
	cmd := &cobra.Command{
		Use:   "editor [file]",
		Short: "open editor the converted C file of CbC",
		Args:  cobra.ExactArgs(1),
		RunE:  cbc2cEditor,
	}
	return cmd
}

func cbc2cEditor(cmd *cobra.Command, args []string) error {
	cfile, err := cbcfile2cfilepath(args[0])
	if err != nil {
		return fmt.Errorf("failed cbc2c command %v", err)
	}
	if editor, ok := os.LookupEnv("EDITOR"); ok {
		editoCMD := exec.Command(editor, cfile)
		editoCMD.Stdin = cmd.InOrStdin()
		editoCMD.Stdout = cmd.OutOrStdout()
		editoCMD.Stderr = cmd.ErrOrStderr()
		return editoCMD.Run()
	}
	return errors.New("failed lookup $EDITOR")
}

func fileExists(filename string) bool {
	info, err := os.Stat(filename)
	if os.IsNotExist(err) {
		return false
	}
	return !info.IsDir()
}