refactor: modularize chat backend, update docs for .m4s segments

backend/chat/src/config/config.go

@@ -0,0 +1,118 @@
+package config
+
+import (
+	"os"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// Defaults and constants
+const (
+	AdminSessionCookieName = "linearvoid_admin_session"
+	MaxAdminUploadBytes    int64 = 2 * 1024 * 1024 * 1024
+	DefaultAdminChunkSize  int64 = 8 * 1024 * 1024
+	MaxAdminChunkSize      int64 = 32 * 1024 * 1024
+	DefaultRateLimitMax          = 10
+	DefaultRateLimitWindow       = 10 * time.Second
+	DefaultAdminSessionTTL       = 12 * time.Hour
+	DefaultChatPort              = "3000"
+)
+
+// PlaylistPath returns the playlist file path from env or default.
+func PlaylistPath() string {
+	p := strings.TrimSpace(os.Getenv("PLAYLIST_PATH"))
+	if p == "" {
+		return "/app/playlist/playlist.txt"
+	}
+	return p
+}
+
+// MediaDir returns the media directory from env or default.
+func MediaDir() string {
+	d := strings.TrimSpace(os.Getenv("MEDIA_DIR"))
+	if d == "" {
+		return "/app/media"
+	}
+	return d
+}
+
+// AdminUsername returns the admin username from env or default.
+func AdminUsername() string {
+	u := strings.TrimSpace(os.Getenv("ADMIN_USERNAME"))
+	if u == "" {
+		return "admin"
+	}
+	return u
+}
+
+// AdminPassword returns the admin password from env or default.
+func AdminPassword() string {
+	p := strings.TrimSpace(os.Getenv("ADMIN_PASSWORD"))
+	if p == "" {
+		return "admin"
+	}
+	return p
+}
+
+// AdminSessionTTL returns the admin session TTL from env or default.
+func AdminSessionTTL() time.Duration {
+	raw := strings.TrimSpace(os.Getenv("ADMIN_SESSION_TTL_HOURS"))
+	if raw == "" {
+		return DefaultAdminSessionTTL
+	}
+	hours, err := strconv.Atoi(raw)
+	if err != nil || hours <= 0 {
+		return DefaultAdminSessionTTL
+	}
+	return time.Duration(hours) * time.Hour
+}
+
+// RateLimitMax returns the chat rate limit max messages per window.
+func RateLimitMax() int {
+	raw := strings.TrimSpace(os.Getenv("CHAT_RATE_LIMIT_MAX"))
+	if raw == "" {
+		return DefaultRateLimitMax
+	}
+	v, err := strconv.Atoi(raw)
+	if err != nil || v <= 0 {
+		return DefaultRateLimitMax
+	}
+	return v
+}
+
+// RateLimitWindow returns the chat rate limit window duration.
+func RateLimitWindow() time.Duration {
+	raw := strings.TrimSpace(os.Getenv("CHAT_RATE_LIMIT_WINDOW_S"))
+	if raw == "" {
+		return DefaultRateLimitWindow
+	}
+	v, err := strconv.Atoi(raw)
+	if err != nil || v <= 0 {
+		return DefaultRateLimitWindow
+	}
+	return time.Duration(v) * time.Second
+}
+
+// ChatPort returns the chat service port from env or default.
+func ChatPort() string {
+	p := strings.TrimSpace(os.Getenv("CHAT_PORT"))
+	if p == "" {
+		return DefaultChatPort
+	}
+	return p
+}
+
+// RedisAddress returns the Redis address from env or default.
+func RedisAddress() string {
+	a := strings.TrimSpace(os.Getenv("REDIS_URL"))
+	if a == "" {
+		return "redis:6379"
+	}
+	return a
+}
+
+// DatabaseURL returns the database URL from env (empty = SQLite default).
+func DatabaseURL() string {
+	return strings.TrimSpace(os.Getenv("DATABASE_URL"))
+}