Gacha pool overhaul and DB backup wizard

server/cmd/wizard/backup.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	"database/sql"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+
+	"charm.land/huh/v2/spinner"
+
+	_ "modernc.org/sqlite"
+)
+
+const (
+	gameDBPath    = "db/game.db"
+	backupDir     = "db/backups"
+	backupSuffix  = ".bak"
+	backupRetainN = 10
+)
+
+func backupGameDB() {
+	if _, err := os.Stat(gameDBPath); errors.Is(err, os.ErrNotExist) {
+		return
+	}
+
+	_ = spinner.New().Title("  Backing up db/game.db...").Action(func() {
+		if err := os.MkdirAll(backupDir, 0o755); err != nil {
+			fmt.Fprintf(os.Stderr, "  failed to create %s: %v\n", backupDir, err)
+			return
+		}
+
+		ts := time.Now().UTC().Format("20060102T150405Z")
+		dest := filepath.Join(backupDir, fmt.Sprintf("game.db.%s%s", ts, backupSuffix))
+
+		db, err := sql.Open("sqlite", gameDBPath+"?_pragma=busy_timeout(5000)")
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "  failed to open %s: %v\n", gameDBPath, err)
+			return
+		}
+		defer db.Close()
+
+		escaped := strings.ReplaceAll(dest, "'", "''")
+		if _, err := db.Exec(fmt.Sprintf("VACUUM INTO '%s'", escaped)); err != nil {
+			fmt.Fprintf(os.Stderr, "  VACUUM INTO failed: %v\n", err)
+			_ = os.Remove(dest)
+			return
+		}
+
+		pruneOldBackups()
+	}).Run()
+}
+
+func pruneOldBackups() {
+	entries, err := os.ReadDir(backupDir)
+	if err != nil {
+		return
+	}
+	var backups []os.DirEntry
+	for _, e := range entries {
+		if !e.IsDir() && strings.HasPrefix(e.Name(), "game.db.") && strings.HasSuffix(e.Name(), backupSuffix) {
+			backups = append(backups, e)
+		}
+	}
+	if len(backups) <= backupRetainN {
+		return
+	}
+	sort.Slice(backups, func(i, j int) bool { return backups[i].Name() < backups[j].Name() })
+	for _, old := range backups[:len(backups)-backupRetainN] {
+		_ = os.Remove(filepath.Join(backupDir, old.Name()))
+	}
+}

server/cmd/wizard/main.go

@@ -79,6 +79,7 @@ func main() {
 		validateTools()
 		validateProtocIncludes()
 		runProtoc()
+		backupGameDB()
 		runMigrate()
 		downloadDeps()
 	}