package swampfile

import (
	"caj-larsson/bog/dataswamp/swampfile"
	"github.com/spf13/afero"
	"io/fs"
	"os"
	"path"
	"time"
)

type SwampFile struct {
	filename string
	file     afero.File
}

func (f SwampFile) Path() string {
	return f.filename
}

func (f SwampFile) Size() int64 {
	stat, _ := f.file.Stat()
	return int64(stat.Size())
}

func (f SwampFile) Read(p []byte) (int, error) {
	return f.file.Read(p)
}

func (f SwampFile) Write(p []byte) (int, error) {
	return f.file.Write(p)
}

func (f SwampFile) Close() error {
	return f.file.Close()
}

func (f SwampFile) Seek(offset int64, whence int) (int64, error) {
	return f.file.Seek(offset, whence)
}

func (f SwampFile) Modified() time.Time {
	stat, _ := f.file.Stat()
	return stat.ModTime()
}

func (f SwampFile) Truncate() {
	err := f.file.Truncate(0)
	if err != nil {
		panic(err)
	}
}

// The actual repository
type Repository struct {
	Fs afero.Fs
}

func NewRepository() swampfile.Repository {
	return Repository{afero.NewMemMapFs()}
}

func (r Repository) Create(filename string, namespace_stub string) (swampfile.SwampInFile, error) {
	abs_path := path.Join(namespace_stub, filename)
	dir := path.Dir(abs_path)
	r.Fs.MkdirAll(dir, 0750)
	file, err := r.Fs.OpenFile(abs_path, os.O_RDWR|os.O_CREATE, 0644)

	if err != nil {
		panic(err)
	}

	bf := SwampFile{filename, file}

	return bf, nil
}

func (r Repository) Open(filename string, namespace_stub string) (swampfile.SwampOutFile, error) {
	abs_path := path.Join(namespace_stub, filename)

	dir := path.Dir(abs_path)
	r.Fs.MkdirAll(dir, 0750)
	file, err := r.Fs.OpenFile(abs_path, os.O_RDONLY, 0644)

	if err != nil {
		return nil, swampfile.ErrNotExists
	}

	bf := SwampFile{filename, file}
	return bf, nil
}

func (r Repository) Delete(filename string, namespace_stub string) {
	abs_path := path.Join(namespace_stub, filename)
	r.Fs.Remove(abs_path)
}

func (r Repository) DeleteOlderThan(namespace_stub string, ts time.Time) ([]swampfile.DeletedSwampFile, error) {
	df := []swampfile.DeletedSwampFile{}

	err := afero.Walk(r.Fs, namespace_stub, func(path string, info fs.FileInfo, err error) error {
		if err != nil {
			return err
		}

		if info.Mode().IsRegular() {
			if info.ModTime().Before(ts) {
				df = append(df, swampfile.DeletedSwampFile{path, info.Size()})
				r.Fs.Remove(path)
			}
			return nil
		}

		if !info.Mode().IsDir() {
			return swampfile.ErrCorrupted
		}
		return nil
	})
	return df, err
}