caching icons automatically

internal/rendering/config.go

@@ -136,3 +136,12 @@ func (rc *Config) LoadConfigFile(file string) error {
 
 	return toml.Unmarshal(content, rc)
 }
+
+func (c *Config) Init() error {
+	for i, w := range c.Template.Websites {
+		c.Template.Websites[i].Cache()
+		fmt.Println(w.ImageUrl)
+	}
+
+	return nil
+}

internal/rendering/website_cards.go

@@ -1,7 +1,76 @@
 package rendering
 
+import (
+	"crypto/sha1"
+	"encoding/hex"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"os"
+	"path/filepath"
+)
+
 type Website struct {
-	Url      string
-	Name     string
-	ImageUrl string
+	Url       string
+	Name      string
+	ImageUrl  string
+	IsFetched bool
+}
+
+const CacheUrl = "cache"
+
+func GetCacheDir() (string, error) {
+	baseDir, err := os.UserCacheDir()
+	if err != nil {
+		return "", err
+	}
+	cacheDir := filepath.Join(baseDir, "startpage")
+	err = os.MkdirAll(cacheDir, 0o755)
+	if err != nil {
+		return "", err
+	}
+	return cacheDir, nil
+}
+
+func hashUrl(url string) string {
+	h := sha1.New()
+	io.WriteString(h, url)
+	return hex.EncodeToString(h.Sum(nil))
+}
+
+func (w *Website) Cache() error {
+	if w.IsFetched {
+		return nil
+	}
+
+	cacheDir, err := GetCacheDir()
+	if err != nil {
+		return err
+	}
+
+	filename := hashUrl(w.ImageUrl)
+	fmt.Println(w.ImageUrl + " => " + filename)
+	targetPath := filepath.Join(cacheDir, filename)
+	resp, err := http.Get(w.ImageUrl)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	file, err := os.Create(targetPath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	_, err = io.Copy(file, resp.Body)
+
+	if err != nil {
+		return err
+	}
+
+	w.ImageUrl, _ = url.JoinPath(CacheUrl, filename)
+	w.IsFetched = true
+	return nil
 }