filters

type ContentFilterConfig struct {
	// Profanity filtering
	EnableProfanity bool
	ProfanityList   []string
	ProfanityAction string // "block", "replace", "flag"
	ReplaceWith     string

	// URL filtering
	EnableURLFilter bool
	AllowedDomains  []string
	BlockedDomains  []string

	// Spam detection
	EnableSpamDetection bool
	MaxURLs             int
	MaxMentions         int
	MaxEmojis           int
	MaxRepeatedChars    int
}

type FilterChain interface {
	// Add registers a filter
	Add(filter MessageFilter)

	// Remove unregisters a filter
	Remove(filterName string)

	// Apply runs all filters in priority order
	Apply(ctx context.Context, msg *streaming.Message, recipient streaming.EnhancedConnection) (*streaming.Message, error)

	// List returns all registered filters
	List() []MessageFilter
}

type FilterCondition func(ctx context.Context, msg *streaming.Message, recipient streaming.EnhancedConnection) bool

type FilterFunc func(ctx context.Context, msg *streaming.Message, recipient streaming.EnhancedConnection) (*streaming.Message, error)

type MessageFilter interface {
	// Name returns unique filter identifier
	Name() string

	// Filter processes message and returns filtered result
	// Returns nil to block message
	Filter(ctx context.Context, msg *streaming.Message, recipient streaming.EnhancedConnection) (*streaming.Message, error)

	// Priority returns filter execution order (lower = earlier)
	Priority() int
}

type MetadataFilterConfig struct {
	// Filter by room/channel
	FilterByRoom    bool
	FilterByChannel bool

	// Filter by message type
	FilterByType bool
	AllowedTypes []string
	BlockedTypes []string

	// Custom conditions
	CustomConditions map[string]FilterCondition
}

type PermissionChecker interface {
	// HasPermission checks if recipient can receive message
	HasPermission(ctx context.Context, recipient streaming.EnhancedConnection, msg *streaming.Message) (bool, error)
}

type SizeFilterConfig struct {
	// Max message size in bytes
	MaxMessageSize int

	// Truncation
	EnableTruncation bool
	TruncateLength   int

	// Compression
	EnableCompression     bool
	CompressionThreshold  int     // Compress if larger than this
	CompressionMinSavings float64 // Only use compression if saves this % (0.0-1.0)
}