From 3296649caeb200dbbb640359a783d1fa997f7d09 Mon Sep 17 00:00:00 2001
From: Maxim Lebedev <git@toby3d.me>
Date: Sat, 11 Nov 2023 23:53:58 +0600
Subject: [PATCH] :building_construction: Use subfolders for translations

---
 internal/common/common.go |  9 ++++----
 main.go                   | 48 +++++++++++++++++++++++++++++++++++----
 2 files changed, 49 insertions(+), 8 deletions(-)

diff --git a/internal/common/common.go b/internal/common/common.go
index dc060a3..e818105 100644
--- a/internal/common/common.go
+++ b/internal/common/common.go
@@ -1,13 +1,14 @@
 package common
 
 const (
-	HeaderAcceptLanguage string = "Accept-Language"
-	HeaderContentType    string = "Content-Type"
+	HeaderAcceptLanguage  string = "Accept-Language"
+	HeaderContentLanguage string = "Content-Language"
+	HeaderContentType     string = "Content-Type"
 )
 
 const (
-	MIMETextHTML                           string = "text/html"
-	MIMETextHTMLCharsetUTF8                string = MIMETextHTML + "; " + charsetUTF8
+	MIMETextHTML            string = "text/html"
+	MIMETextHTMLCharsetUTF8 string = MIMETextHTML + "; " + charsetUTF8
 )
 
 const charsetUTF8 string = "charset=UTF-8"
diff --git a/main.go b/main.go
index 6259c66..9b2333c 100644
--- a/main.go
+++ b/main.go
@@ -18,6 +18,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"runtime/pprof"
+	"strings"
 	"syscall"
 	"time"
 	_ "time/tzdata"
@@ -38,6 +39,7 @@ import (
 	"source.toby3d.me/toby3d/home/internal/templateutil"
 	themefsrepo "source.toby3d.me/toby3d/home/internal/theme/repository/fs"
 	themeucase "source.toby3d.me/toby3d/home/internal/theme/usecase"
+	"source.toby3d.me/toby3d/home/internal/urlutil"
 )
 
 type (
@@ -81,12 +83,42 @@ func NewApp(ctx context.Context, config *domain.Config) (*App, error) {
 	server := &http.Server{
 		Addr: config.AddrPort().String(),
 		Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			tags, _, err := language.ParseAcceptLanguage(r.Header.Get(common.HeaderAcceptLanguage))
-			if err != nil || len(tags) == 0 {
-				tags = append(tags, language.English)
+			head, tail := urlutil.ShiftPath(r.URL.Path)
+
+			if head == "" {
+				tags, _, err := language.ParseAcceptLanguage(r.Header.Get(common.HeaderAcceptLanguage))
+				if err != nil || len(tags) == 0 {
+					tags = append(tags, language.English)
+				}
+
+				lang, _, _ := matcher.Match(tags...)
+
+				http.Redirect(w, r, "/"+lang.String()+"/", http.StatusSeeOther)
+
+				return
 			}
 
-			lang, _, _ := matcher.Match(tags...)
+			lang, err := language.Parse(head)
+			if err != nil || lang == language.Und {
+				res, err := staticer.Do(r.Context(), r.URL.Path)
+				if err != nil {
+					if errors.Is(err, fs.ErrNotExist) {
+						http.Error(w, err.Error(), http.StatusNotFound)
+
+						return
+					}
+
+					http.Error(w, err.Error(), http.StatusInternalServerError)
+
+					return
+				}
+
+				http.ServeContent(w, r, res.Name(), domain.ResourceModTime(res), res)
+
+				return
+			}
+
+			r.URL.Path = tail
 
 			s, err := siter.Do(r.Context(), lang)
 			if err != nil {
@@ -121,6 +153,14 @@ func NewApp(ctx context.Context, config *domain.Config) (*App, error) {
 				return
 			}
 
+			contentLanguage := make([]string, len(p.Translations))
+			for i := range p.Translations {
+				base, _ := p.Translations[i].Language.Base()
+				contentLanguage[i] = base.String()
+			}
+
+			w.Header().Set(common.HeaderContentLanguage, strings.Join(contentLanguage, ", "))
+
 			tpl, err := themer.Do(r.Context())
 			if err != nil {
 				http.Error(w, err.Error(), http.StatusInternalServerError)