// Copyright 2024 Matthew Rich <matthewrich.conf@gmail.com>. All rights reserved.

package tempdir

import (
	"os"
	"path/filepath"
	"strings"
	"fmt"
	"io/fs"
	"log/slog"
	"io"
)

type Path string

func (t *Path) ValidPath() bool {
	if filepath.IsAbs(string(*t)) && strings.HasPrefix(string(*t), os.TempDir()) && len(*t) > 1 {
		return true
	}
	return false
}

func (t *Path) Create() (err error) {
	if t.ValidPath() && t.Exists() {
		return
	}
	slog.Info("tempdir.Create()", "path", string(*t))
	var TempDir string
	TempDir, err = os.MkdirTemp("", string(*t))
	if err != nil || TempDir == "" {
		err = fmt.Errorf("%w: Failed creating temp dir %s", err, TempDir)
	}
	*t = Path(TempDir)
	return
}

func (t *Path) Remove() {
	slog.Info("tempdir.Remove()", "path", *t)
	if t.ValidPath() {
		os.RemoveAll(string(*t))
	}
}

func (t *Path) Open(name string) (r io.ReadCloser, err error) {
	path := t.FilePath(name)
	r, err = os.Open(path)
	return
}

func (t *Path) CreateFileFromReader(name string, r io.Reader) (path string, err error) {
	path = filepath.Join(string(*t), name)
	_, statErr := os.Stat(path)
	if os.IsNotExist(statErr) {
		if file, createErr := os.Create(path); createErr == nil {
			defer file.Close()
			buf := make([]byte, 32*1024)
			_, err = io.CopyBuffer(file, r, buf)
		} else {
			err = createErr
		}
	}
	return
}

func (t *Path) CreateFile(name string, content string) (err error) {
	path := filepath.Join(string(*t), name)
	_, statErr := os.Stat(path)
	if os.IsNotExist(statErr) {
		if file, createErr := os.Create(path); createErr == nil {
			defer file.Close()
			_, err = file.Write([]byte(content))
		} else {
			err = createErr
		}
	}
	return
}

func (t *Path) FileExists(name string) bool {
	path := t.FilePath(name)
	_, statErr := os.Stat(path)
	return ! os.IsNotExist(statErr)
}

func (t *Path) Exists() (bool) {
	_, statErr := os.Stat(string(*t))
	return ! os.IsNotExist(statErr)
}

func (t *Path) FilePath(name string) string {
	return filepath.Join(string(*t), name)
}

func (t *Path) URIPath(name string) string {
	return fmt.Sprintf("file://%s", t.FilePath(name))
}

func (t *Path) Mkdir(name string, mode os.FileMode) (err error) {
	var path string
	if path, err = filepath.Abs(filepath.Join(string(*t), name)); err == nil {
		if ! (*Path)(&path).ValidPath() {
			return fmt.Errorf("Invalid path %s of %s", path, *t)
		}
		_, statErr := os.Stat(path)
		if os.IsNotExist(statErr) {
			err = os.Mkdir(path, mode)
		}
	}
	return
}

func (t *Path) DirFS() fs.FS {
	if t.ValidPath() {
		return os.DirFS(string(*t))
	}
	return nil
}