package build

import (
	"fmt"
	"os"
	"path/filepath"
)

type Fetcher interface {
	Fetch(tempDir string) error
}

type BlankFetcher struct{}

func (BlankFetcher) Fetch(tempDir string) error {
	return fmt.Errorf("no sources were configured")
}

var _ Fetcher = (*GitFetcher)(nil)

type GitFetcher struct {
	Repository, Ref string
}

func (g GitFetcher) Fetch(tempDir string) error {

	repoDir := filepath.Join(tempDir, "repo")
	exitCode, out := execCommand("git", "clone", "--depth=1", g.Repository, repoDir)
	if exitCode != 0 {
		return fmt.Errorf("git clone returned %d, output: %v", exitCode, string(out))
	}

	err := os.Chdir(repoDir)
	if err != nil {
		return fmt.Errorf("changing to repository directory: %w", err)
	}

	if g.Ref != "" {
		exitCode, out = execCommand("git", "fetch", "--depth=1", "origin", g.Ref)
		if exitCode != 0 {
			return fmt.Errorf("fetch clone returned %d, output: %v", exitCode, string(out))
		}

		exitCode, out = execCommand("git", "checkout", g.Ref)
		if exitCode != 0 {
			return fmt.Errorf("git checkout returned %d, output: %v", exitCode, string(out))
		}
	}

	return nil
}