// Package git utilizes the git CLI to retrieve and set information
// from the current repository
package git

import (
	"bufio"
	"bytes"
	"fmt"
	"os"
	"os/exec"
	"regexp"
	"strings"
)

var (
	// ErrRemoteNotFound signalizes there was no remote found
	ErrRemoteNotFound = fmt.Errorf("no push remote found")

	pushRemoteRegex = regexp.MustCompile(`origin.*\(push\)`)
)

// GetPushRemote gets the remote configured as push-remote and returns
// ErrRemoteNotFound in case none is found
func GetPushRemote() (remote string, err error) {
	data, err := runGitCLI([]string{"remote", "-v"})
	if err != nil {
		return "", fmt.Errorf("getting remotes")
	}

	scanner := bufio.NewScanner(bytes.NewReader(data))
	for scanner.Scan() {
		if err = scanner.Err(); err != nil {
			return "", fmt.Errorf("scanning output: %w", err)
		}

		if !pushRemoteRegex.Match(scanner.Bytes()) {
			continue
		}

		tokens := strings.Fields(scanner.Text())
		if len(tokens) < 2 { //nolint:mnd
			continue
		}

		return tokens[1], nil
	}

	return "", ErrRemoteNotFound
}

// SetLocalConfig applies the param with its value on the local git repo
func SetLocalConfig(param, value string) (err error) {
	if _, err = runGitCLI([]string{"config", "--local", param, value}); err != nil {
		return fmt.Errorf("setting config: %w", err)
	}

	return nil
}

func runGitCLI(args []string) (output []byte, err error) {
	cmd := exec.Command("git", args...)
	cmd.Env = os.Environ()
	if cmd.Dir, err = os.Getwd(); err != nil {
		return nil, fmt.Errorf("getting cwd: %w", err)
	}

	data, err := cmd.Output()
	if err != nil {
		return nil, fmt.Errorf("running command: %w", err)
	}

	return data, nil
}