From 6f7ff6fe47a39f00dbac3717cde91cbdebf6d9ea Mon Sep 17 00:00:00 2001
From: perennial <mail@perennialte.ch>
Date: Sun, 22 Sep 2024 19:24:05 +1000
Subject: [PATCH] Improve error handling and add fallbacks for config

This commit improves the error handling in the configuration loading
process, specifically for URL validations.

It replaces panic calls with proper error returns and adds
fallback mechanisms for invalid proxy server and repo URLs.

Warning logs are now used for these configuration issues.
---
 config/config.go | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/config/config.go b/config/config.go
index c680e3e..ca377cd 100644
--- a/config/config.go
+++ b/config/config.go
@@ -84,10 +84,10 @@ func validateURL(urlString string, urlType string) (*url.URL, error) {
 		return nil, err
 	}
 	if (parsedURL.Scheme == "") != (parsedURL.Host == "") {
-		log.Panicf("%s URL is weird: %s\nPlease specify e.g. https://example.com", urlType, urlString)
+		return nil, fmt.Errorf("%s URL is invalid: %s. Please specify e.g. https://example.com", urlType, urlString)
 	}
 	if strings.HasSuffix(parsedURL.Path, "/") {
-		log.Panicf("%s URL path (%s) cannot end in /: %s\nPixivFE does not support this now, sorry", urlType, parsedURL.Path, urlString)
+		return nil, fmt.Errorf("%s URL path (%s) cannot end in /: %s. PixivFE does not support this now", urlType, parsedURL.Path, urlString)
 	}
 	return parsedURL, nil
 }
@@ -145,7 +145,10 @@ func (s *ServerConfig) LoadConfig() error {
 	// Validate proxy server URL
 	proxyURL, err := validateURL(s.ProxyServer_staging, "Proxy server")
 	if err != nil {
-		return fmt.Errorf("Invalid proxy server URL: %v", err)
+		log.Printf("[WARNING] Invalid proxy server URL: %v. Falling back to built-in proxy URL.", err)
+		proxyURL, _ = url.Parse(BuiltinProxyUrl) // We know this is valid
+	} else {
+		log.Printf("Proxy server set to: %s\n", proxyURL.String())
 	}
 	s.ProxyServer = *proxyURL
 	log.Printf("Proxy server set to: %s\n", s.ProxyServer.String())
@@ -154,17 +157,19 @@ func (s *ServerConfig) LoadConfig() error {
 	// Validate repo URL
 	repoURL, err := validateURL(s.RepoURL, "Repo")
 	if err != nil {
-		return fmt.Errorf("Invalid repo URL: %v", err)
+		log.Printf("[WARNING] Invalid repo URL: %v. Using default repo URL.", err)
+		s.RepoURL = "https://codeberg.org/VnPower/PixivFE" // Use a default value
+	} else {
+		s.RepoURL = repoURL.String()
+		log.Printf("Repo URL set to: %s\n", s.RepoURL)
 	}
-	s.RepoURL = repoURL.String()
-	log.Printf("Repo URL set to: %s\n", s.RepoURL)
 
 	// Validate TokenLoadBalancing
 	switch s.TokenLoadBalancing {
 	case "round-robin", "random", "least-recently-used":
 		// Valid options
 	default:
-		log.Printf("Invalid PIXIVFE_TOKEN_LOAD_BALANCING value: %s. Defaulting to 'round-robin'.\n", s.TokenLoadBalancing)
+		log.Printf("[WARNING] Invalid PIXIVFE_TOKEN_LOAD_BALANCING value: %s. Defaulting to 'round-robin'.\n", s.TokenLoadBalancing)
 		s.TokenLoadBalancing = "round-robin"
 	}