From 797e115191e7df4d16d9bec2def0c3cc7a4d9155 Mon Sep 17 00:00:00 2001
From: Hazel Noack <hazel@webcontact.de>
Date: Wed, 16 Jul 2025 14:24:42 +0200
Subject: [PATCH] rewrote cache to work better

---
 internal/cache/cache.go      | 97 ++++++++++++++++++++++++++++++++++++
 internal/rendering/config.go |  9 ----
 internal/server/server.go    | 24 +++++----
 3 files changed, 111 insertions(+), 19 deletions(-)
 create mode 100644 internal/cache/cache.go

diff --git a/internal/cache/cache.go b/internal/cache/cache.go
new file mode 100644
index 0000000..950ed43
--- /dev/null
+++ b/internal/cache/cache.go
@@ -0,0 +1,97 @@
+package cache
+
+import (
+	"crypto/sha1"
+	"encoding/hex"
+	"errors"
+	"io"
+	"net/http"
+	"net/url"
+	"os"
+	"path/filepath"
+
+	"github.com/labstack/echo/v4"
+)
+
+type Cache struct {
+	CacheDir string
+	Disabled bool
+}
+
+func getCacheDir() (string, error) {
+	baseDir, err := os.UserCacheDir()
+	if err != nil {
+		baseDir = "/tmp"
+	}
+	cacheDir := filepath.Join(baseDir, "startpage")
+	err = os.MkdirAll(cacheDir, 0o755)
+	if err != nil {
+		return "", err
+	}
+	return cacheDir, nil
+}
+
+func getProfileCacheDir(profile string) (string, error) {
+	var profileCacheDir string
+
+	cacheDir, err := getCacheDir()
+	if err != nil {
+		return profileCacheDir, err
+	}
+
+	profileCacheDir = filepath.Join(cacheDir, profile)
+	err = os.MkdirAll(cacheDir, 0o755)
+	return profileCacheDir, err
+}
+
+func NewCache(profile string) Cache {
+	cacheDir, err := getProfileCacheDir(profile)
+
+	return Cache{
+		CacheDir: cacheDir,
+		Disabled: err != nil,
+	}
+}
+
+const baseCacheUrl = "cache"
+
+func (c Cache) StartStaticServer(e *echo.Echo) error {
+	e.Static("/"+baseCacheUrl, c.CacheDir)
+	return nil
+}
+
+func hashUrl(url string) string {
+	h := sha1.New()
+	io.WriteString(h, url)
+	return hex.EncodeToString(h.Sum(nil))
+}
+
+func (c Cache) CacheUrl(urlString string) (string, error) {
+	filename := hashUrl(urlString) + filepath.Ext(urlString)
+	targetPath := filepath.Join(c.CacheDir, filename)
+
+	// if the file was already downloaded it doesn't need to be downloaded again
+	if _, err := os.Stat(targetPath); errors.Is(err, os.ErrNotExist) {
+		resp, err := http.Get(urlString)
+		if !errors.Is(err, os.ErrNotExist) {
+			return urlString, err
+		}
+		defer resp.Body.Close()
+
+		file, err := os.Create(targetPath)
+		if err != nil {
+			return urlString, err
+		}
+		defer file.Close()
+
+		_, err = io.Copy(file, resp.Body)
+
+		if err != nil {
+			return urlString, err
+		}
+	} else {
+		return url.JoinPath(baseCacheUrl, filename)
+	}
+
+	return url.JoinPath(baseCacheUrl, filename)
+}
diff --git a/internal/rendering/config.go b/internal/rendering/config.go
index bd9f6f2..8348582 100644
--- a/internal/rendering/config.go
+++ b/internal/rendering/config.go
@@ -138,12 +138,3 @@ func (rc *Config) LoadConfigFile(file string) error {
 
 	return toml.Unmarshal(content, rc)
 }
-
-func (c *Config) Init() error {
-	log.Println("downloading website icons...")
-	for i := range c.Template.Websites {
-		c.Template.Websites[i].Cache()
-	}
-
-	return nil
-}
diff --git a/internal/server/server.go b/internal/server/server.go
index f5b333e..a14fa28 100644
--- a/internal/server/server.go
+++ b/internal/server/server.go
@@ -5,6 +5,7 @@ import (
 	"net/http"
 	"strconv"
 
+	"gitea.elara.ws/Hazel/transfem-startpage/internal/cache"
 	"gitea.elara.ws/Hazel/transfem-startpage/internal/rendering"
 	"github.com/labstack/echo/v4"
 )
@@ -17,11 +18,6 @@ func Start(profile string) error {
 		return err
 	}
 
-	err = Config.Init()
-	if err != nil {
-		return err
-	}
-
 	err = Config.FetchDiyHrt()
 	if err != nil {
 		log.Println(err)
@@ -30,11 +26,19 @@ func Start(profile string) error {
 	e := echo.New()
 
 	// statically serve the file
-	cacheDir, err := rendering.GetCacheDir()
-	if err == nil {
-		e.Static("/cache", cacheDir)
-	} else {
-		log.Println("didn't enable cache dir", err)
+	cache := cache.NewCache(profile)
+	if !cache.Disabled {
+		cache.StartStaticServer(e)
+
+		log.Println("downloading website icons...")
+		for i, w := range Config.Template.Websites {
+			u, err := cache.CacheUrl(w.ImageUrl)
+			if err != nil {
+				log.Println(err)
+			}
+			Config.Template.Websites[i].ImageUrl = u
+			Config.Template.Websites[i].IsFetched = true
+		}
 	}
 
 	// https://echo.labstack.com/docs/cookbook/embed-resources