package packr

import (
	"os"
	"path/filepath"
	"runtime"
	"strings"

	"github.com/gobuffalo/packr/v2/plog"
)

func construct(name string, path string) *Box {
	return &Box{
		Path:          path,
		Name:          name,
		ResolutionDir: resolutionDir(path),
		resolvers:     resolversMap{},
		dirs:          dirsMap{},
	}
}

func resolutionDirTestFilename(filename, og string) (string, bool) {
	ng := filepath.Join(filepath.Dir(filename), og)

	// // this little hack courtesy of the `-cover` flag!!
	cov := filepath.Join("_test", "_obj_test")
	ng = strings.Replace(ng, string(filepath.Separator)+cov, "", 1)

	if resolutionDirExists(ng, og) {
		return ng, true
	}

	ng = filepath.Join(os.Getenv("GOPATH"), "src", ng)
	if resolutionDirExists(ng, og) {
		return ng, true
	}

	return og, false
}

func resolutionDirExists(s, og string) bool {
	_, err := os.Stat(s)
	if err != nil {
		return false
	}
	plog.Debug("packr", "resolutionDir", "original", og, "resolved", s)
	return true
}

func resolutionDir(og string) string {
	ng, _ := filepath.Abs(og)

	if resolutionDirExists(ng, og) {
		return ng
	}

	// packr.New
	_, filename, _, _ := runtime.Caller(3)
	ng, ok := resolutionDirTestFilename(filename, og)
	if ok {
		return ng
	}

	// packr.NewBox (deprecated)
	_, filename, _, _ = runtime.Caller(4)
	ng, ok = resolutionDirTestFilename(filename, og)
	if ok {
		return ng
	}

	return og
}