package webfs

import (
	"embed"
	"fmt"
	"io/fs"
	"path"
)

//go:embed assets scripts styles templates
var webFS embed.FS

var Root fs.FS

func init() {
	Root = prefixFS{root: "web", fs: webFS}
}

type prefixFS struct {
	root string
	fs   fs.FS
}

func (p prefixFS) Open(name string) (fs.File, error) {
	clean := path.Clean(name)

	if clean == p.root {
		return p.fs.Open(".")
	}

	return p.fs.Open(clean[len(p.root + "/"):])
}

func (p prefixFS) ReadDir(name string) ([]fs.DirEntry, error) {
	clean := path.Clean(name)

	if clean == p.root {
		return fs.ReadDir(p.fs, ".")
	}

	return fs.ReadDir(p.fs, clean[len(p.root + "/"):])
}

func Sub(dir string) fs.FS {
	sub, err := fs.Sub(Root, dir)
	if err != nil {
		panic(fmt.Errorf("failed to create subfs: %w", err))
	}

	return sub
}