Mostly finish docs

Actually start to parse things

internal/darkstorm_backend/darkstorm.go

@@ -1,7 +1,90 @@
 package darkstorm
 
-import "net/http"
+import (
+	"crypto/ed25519"
+	"errors"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/golang-jwt/jwt/v5"
+)
+
+var (
+	ErrApiKeyUnauthorized = errors.New("api key invalid")
+	ErrTokenUnauthorized  = errors.New("token invalid")
+)
 
 type Backend struct {
-	http.ServeMux
+	userTable Table[User]
+	keyTable  Table[Key]
+	m         *http.ServeMux
+	jwtPriv   ed25519.PrivateKey
+	jwtPub    ed25519.PublicKey
+	apps      []App
+}
+
+func NewBackend(keyTable Table[Key], apps ...App) (*Backend, error) {
+	b := &Backend{
+		keyTable: keyTable,
+		m:        &http.ServeMux{},
+		apps:     apps,
+	}
+	//TODO: register paths to the mux
+	b.startCleanupLoop()
+	return b, nil
+}
+
+func (b *Backend) AddUserAuth(userTable Table[User], privKey, pubKey []byte) {
+	b.userTable = userTable
+	b.jwtPriv = privKey
+	b.jwtPub = pubKey
+}
+
+func (b *Backend) HandleFunc(pattern string, h http.HandlerFunc) {
+	b.m.HandleFunc(pattern, h)
+}
+
+func (b *Backend) startCleanupLoop() {
+	go func() {
+		for range time.Tick(6 * time.Hour) {
+			//TODO
+		}
+	}()
+}
+
+type ParsedHeader struct {
+	u *ReqUser
+	k *Key
+}
+
+func (b *Backend) ParseHeader(r *http.Request) (ParsedHeader, error) {
+	out := ParsedHeader{}
+	key := r.Header.Get("X-API-Key")
+	token := strings.TrimPrefix(r.Header.Get("Authorization"), "Bearer ")
+	if key != "" {
+		apiKey, err := b.keyTable.Get(key)
+		if err != nil {
+			return out, errors.Join(ErrApiKeyUnauthorized, err)
+		}
+		out.k = &apiKey
+	}
+	if token != "" && b.userTable != nil {
+		t, err := jwt.Parse(token, func(t *jwt.Token) (interface{}, error) {
+			return b.jwtPub, nil
+		}, jwt.WithIssuer("darkstorm.tech"), jwt.WithExpirationRequired())
+		if err != nil {
+			return out, errors.Join(ErrTokenUnauthorized, err)
+		}
+		sub, err := t.Claims.GetSubject()
+		if err != nil {
+			return out, errors.Join(ErrTokenUnauthorized, err)
+		}
+		usr, err := b.userTable.Get(sub)
+		if err != nil{
+			return out, errors.Join(ErrTokenUnauthorized, err)
+		}
+		
+	}
+	return out, nil
 }