package http

import (
	"io/fs"
	"net/http"
	"time"
)

type (
	FS struct {
		fs      http.FileSystem
		modtime time.Time
	}

	File struct {
		fp      http.File
		modtime time.Time
	}

	FileInfo struct {
		name    string
		size    int64
		mode    fs.FileMode
		isDir   bool
		modtime time.Time
	}
)

func (fi *FileInfo) Name() string {
	return fi.name
}

func (fi *FileInfo) Size() int64 {
	return fi.size
}

func (fi *FileInfo) Mode() fs.FileMode {
	return fi.mode
}

func (fi *FileInfo) ModTime() time.Time {
	return fi.modtime
}

func (fi *FileInfo) IsDir() bool {
	return fi.isDir
}

func (fi *FileInfo) Sys() any {
	return nil
}

func (file *File) Close() error {
	return file.fp.Close()
}

func (file *File) Read(p []byte) (n int, err error) {
	return file.fp.Read(p)
}

func (file *File) Seek(offset int64, whence int) (int64, error) {
	return file.fp.Seek(offset, whence)
}

func (file *File) Readdir(count int) ([]fs.FileInfo, error) {
	return file.fp.Readdir(count)
}

func (file *File) Stat() (fs.FileInfo, error) {
	fi, err := file.fp.Stat()
	if err != nil {
		return nil, err
	}
	return newFileInfo(fi, file.modtime), nil
}

func (fs *FS) Open(name string) (http.File, error) {
	fp, err := fs.fs.Open(name)
	if err != nil {
		return nil, err
	}
	return &File{fp: fp, modtime: fs.modtime}, nil
}

func newFS(modtime time.Time, fs http.FileSystem) *FS {
	return &FS{
		fs:      fs,
		modtime: modtime,
	}
}

func newFileInfo(fi fs.FileInfo, modtime time.Time) *FileInfo {
	return &FileInfo{
		name:    fi.Name(),
		size:    fi.Size(),
		mode:    fi.Mode(),
		isDir:   fi.IsDir(),
		modtime: modtime,
	}
}