From be973266c630cb70c47a037fe7d8d36c49e6e200 Mon Sep 17 00:00:00 2001
From: partisan <none@noone.no>
Date: Tue, 10 Jun 2025 21:28:40 +0200
Subject: [PATCH] Cache preferred Piped instance to furde reduce start delay

---
 music-youtube.go | 50 +++++++++++++++++++++-------
 video.go         | 86 +++++++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 120 insertions(+), 16 deletions(-)

diff --git a/music-youtube.go b/music-youtube.go
index 698dc71..d262428 100644
--- a/music-youtube.go
+++ b/music-youtube.go
@@ -19,14 +19,13 @@ type MusicAPIResponse struct {
 
 func SearchMusicViaPiped(query string, page int) ([]MusicResult, error) {
 	var lastError error
+
+	// We will try to use preferred instance
 	mu.Lock()
-	defer mu.Unlock()
-
-	for _, instance := range pipedInstances {
-		if disabledInstances[instance] {
-			continue
-		}
+	instance := preferredInstance
+	mu.Unlock()
 
+	if instance != "" && !disabledInstances[instance] {
 		url := fmt.Sprintf(
 			"https://%s/search?q=%s&filter=music_songs&page=%d",
 			instance,
@@ -34,22 +33,51 @@ func SearchMusicViaPiped(query string, page int) ([]MusicResult, error) {
 			page,
 		)
 
+		resp, err := http.Get(url)
+		if err == nil && resp.StatusCode == http.StatusOK {
+			defer resp.Body.Close()
+			var apiResp MusicAPIResponse
+			if err := json.NewDecoder(resp.Body).Decode(&apiResp); err == nil {
+				return convertPipedToMusicResults(instance, apiResp), nil
+			}
+		}
+
+		printWarn("Preferred instance %s failed for music, falling back", instance)
+		disableInstance(instance)
+	}
+
+	// 2. Fallback using others
+	mu.Lock()
+	defer mu.Unlock()
+	for _, inst := range pipedInstances {
+		if disabledInstances[inst] {
+			continue
+		}
+
+		url := fmt.Sprintf(
+			"https://%s/search?q=%s&filter=music_songs&page=%d",
+			inst,
+			url.QueryEscape(query),
+			page,
+		)
+
 		resp, err := http.Get(url)
 		if err != nil || resp.StatusCode != http.StatusOK {
-			printInfo("Disabling instance %s due to error: %v", instance, err)
-			disabledInstances[instance] = true
-			lastError = fmt.Errorf("request to %s failed: %w", instance, err)
+			printInfo("Disabling instance %s due to error: %v", inst, err)
+			disabledInstances[inst] = true
+			lastError = fmt.Errorf("request to %s failed: %w", inst, err)
 			continue
 		}
 
 		defer resp.Body.Close()
 		var apiResp MusicAPIResponse
 		if err := json.NewDecoder(resp.Body).Decode(&apiResp); err != nil {
-			lastError = fmt.Errorf("failed to decode response from %s: %w", instance, err)
+			lastError = fmt.Errorf("failed to decode response from %s: %w", inst, err)
 			continue
 		}
 
-		return convertPipedToMusicResults(instance, apiResp), nil
+		preferredInstance = inst
+		return convertPipedToMusicResults(inst, apiResp), nil
 	}
 
 	return nil, fmt.Errorf("all Piped instances failed, last error: %v", lastError)
diff --git a/video.go b/video.go
index 2c8abe4..8e3ebd0 100644
--- a/video.go
+++ b/video.go
@@ -5,6 +5,9 @@ import (
 	"fmt"
 	"net/http"
 	"net/url"
+	"os"
+	"path/filepath"
+	"strings"
 	"sync"
 	"time"
 )
@@ -12,18 +15,90 @@ import (
 const retryDuration = 12 * time.Hour // Retry duration for unresponding piped instances
 
 var (
-	preferredInstance string
-	pipedInstances    = []string{}
-	disabledInstances = make(map[string]bool)
-	mu                sync.Mutex
+	preferredInstance      string
+	pipedInstanceCacheFile string
+	pipedInstances         = []string{}
+	disabledInstances      = make(map[string]bool)
+	mu                     sync.Mutex
 )
 
 func initPipedInstances() {
-	pipedInstances = config.MetaSearch.Video
+	if config.DriveCacheEnabled {
+		pipedInstanceCacheFile = filepath.Join(config.DriveCache.Path, "piped_instances.txt")
+
+		cached := loadCachedPipedInstances()
+		if len(cached) > 0 {
+			pipedInstances = cached
+			printInfo("Loaded %d cached Piped instances from disk.", len(cached))
+		} else {
+			pipedInstances = config.MetaSearch.Video
+			savePipedInstances(pipedInstances)
+		}
+
+		// load preferred
+		if pref := loadPreferredInstance(); pref != "" {
+			preferredInstance = pref
+			printInfo("Using cached preferred Piped instance: %s", pref)
+		}
+	} else {
+		pipedInstances = config.MetaSearch.Video
+	}
+
 	go checkDisabledInstancesPeriodically()
 	go selectInitialPipedInstance()
 }
 
+func savePreferredInstance(instance string) {
+	if pipedInstanceCacheFile == "" {
+		return
+	}
+	path := filepath.Join(filepath.Dir(pipedInstanceCacheFile), "piped_preferred.txt")
+	if err := os.WriteFile(path, []byte(instance), 0644); err != nil {
+		printWarn("Failed to write preferred Piped instance: %v", err)
+	}
+}
+
+func loadPreferredInstance() string {
+	if pipedInstanceCacheFile == "" {
+		return ""
+	}
+	path := filepath.Join(filepath.Dir(pipedInstanceCacheFile), "piped_preferred.txt")
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return ""
+	}
+	return strings.TrimSpace(string(data))
+}
+
+func loadCachedPipedInstances() []string {
+	if pipedInstanceCacheFile == "" {
+		return nil
+	}
+	data, err := os.ReadFile(pipedInstanceCacheFile)
+	if err != nil {
+		return nil
+	}
+	lines := strings.Split(string(data), "\n")
+	var out []string
+	for _, l := range lines {
+		trimmed := strings.TrimSpace(l)
+		if trimmed != "" {
+			out = append(out, trimmed)
+		}
+	}
+	return out
+}
+
+func savePipedInstances(instances []string) {
+	if pipedInstanceCacheFile == "" {
+		return
+	}
+	content := strings.Join(instances, "\n")
+	if err := os.WriteFile(pipedInstanceCacheFile, []byte(content), 0644); err != nil {
+		printWarn("Failed to write piped instance list to cache: %v", err)
+	}
+}
+
 // VideoAPIResponse matches the structure of the JSON response from the Piped API
 type VideoAPIResponse struct {
 	Items []struct {
@@ -174,6 +249,7 @@ func makeHTMLRequest(query, safe, lang string, page int) (*VideoAPIResponse, err
 
 		// Store new preferred instance
 		preferredInstance = inst
+		savePreferredInstance(inst)
 		return &apiResp, nil
 	}