package bundle

import (
	"archive/zip"
	"context"
	"io"
	"os"
	"path/filepath"
	"strings"

	"github.com/pkg/errors"
	"gitlab.com/wpetit/goweb/logger"
)

type ZipBundle struct {
	archivePath string
}

func (b *ZipBundle) File(filename string) (io.ReadCloser, os.FileInfo, error) {
	reader, err := b.openArchive()
	if err != nil {
		return nil, nil, err
	}

	ctx := logger.With(
		context.Background(),
		logger.F("filename", filename),
	)

	logger.Debug(ctx, "opening file")

	f, err := reader.Open(filename)
	if err != nil {
		return nil, nil, errors.WithStack(err)
	}

	stat, err := f.Stat()
	if err != nil {
		return nil, nil, errors.WithStack(err)
	}

	return f, stat, nil
}

func (b *ZipBundle) Dir(dirname string) ([]os.FileInfo, error) {
	reader, err := b.openArchive()
	if err != nil {
		return nil, err
	}

	defer func() {
		if err := reader.Close(); err != nil {
			panic(errors.WithStack(err))
		}
	}()

	files := make([]os.FileInfo, 0)
	ctx := context.Background()

	for _, f := range reader.File {
		if !strings.HasPrefix(f.Name, dirname) {
			continue
		}

		relPath, err := filepath.Rel(dirname, f.Name)
		if err != nil {
			return nil, errors.Wrap(err, "could not get relative path")
		}

		logger.Debug(
			ctx, "checking file prefix",
			logger.F("dirname", dirname),
			logger.F("filename", f.Name),
			logger.F("relpath", relPath),
		)

		if relPath == filepath.Base(f.Name) {
			files = append(files, f.FileInfo())
		}
	}

	return files, nil
}

func (b *ZipBundle) openArchive() (*zip.ReadCloser, error) {
	zr, err := zip.OpenReader(b.archivePath)
	if err != nil {
		return nil, errors.Wrapf(err, "could not decompress '%v'", b.archivePath)
	}

	return zr, nil
}

func NewZipBundle(archivePath string) *ZipBundle {
	return &ZipBundle{
		archivePath: archivePath,
	}
}