threading

type Config struct {
	// MaxParentAge is the maximum age difference for subject-based matching.
	// Default: 7 days.
	MaxParentAge time.Duration

	// RequireParticipantOverlap requires messages to share at least one
	// participant for subject-based matching. Default: true.
	RequireParticipantOverlap bool

	// SubjectNormalizer is a custom function to normalize subjects.
	// If nil, uses DefaultSubjectNormalizer.
	SubjectNormalizer func(string) string
}

type EmbeddedHint struct {
	// SenderPattern is a pattern to match against participant addresses
	// (e.g., "john.smith" or "john.smith@enron.com").
	SenderPattern string

	// Date is the date of the embedded message (if parseable).
	Date time.Time

	// Subject is the subject of the embedded message (if available).
	Subject string

	// Type indicates the type of embedding: "reply", "forward", "quoted".
	Type string
}

type Reconstructor struct {
	// contains filtered or unexported fields
}

type Stats struct {
	TotalMessages        int `json:"total_messages"`
	TotalThreads         int `json:"total_threads"`
	UniqueSubjects       int `json:"unique_subjects"`
	MessagesWithParent   int `json:"messages_with_parent"`
	MessagesWithRefs     int `json:"messages_with_refs"`
	SingleMessageThreads int `json:"single_message_threads"`
	SmallThreads         int `json:"small_threads"`  // 2-5 messages
	MediumThreads        int `json:"medium_threads"` // 6-20 messages
	LargeThreads         int `json:"large_threads"`  // 21+ messages
}

type Thread struct {
	// ID is a unique identifier for the thread.
	ID string `json:"id"`

	// Subject is the normalized subject of the thread.
	Subject string `json:"subject"`

	// RootMessageID is the MessageID of the first message in the thread.
	RootMessageID string `json:"root_message_id"`

	// MessageIDs contains all message IDs in the thread, sorted by date.
	MessageIDs []string `json:"message_ids"`

	// Participants contains all unique email addresses in the thread.
	Participants []string `json:"participants"`

	// StartDate is the date of the first message.
	StartDate time.Time `json:"start_date"`

	// EndDate is the date of the last message.
	EndDate time.Time `json:"end_date"`

	// Size is the number of messages in the thread.
	Size int `json:"size"`
}

type ThreadableMessage interface {
	// GetMessageID returns the unique message identifier.
	GetMessageID() string

	// GetDate returns the message date.
	GetDate() time.Time

	// GetSubject returns the message subject.
	GetSubject() string

	// GetInReplyTo returns the In-Reply-To header value (may be empty).
	GetInReplyTo() string

	// GetReferences returns the References header values (may be empty).
	GetReferences() []string

	// GetParticipants returns all email addresses involved in the message
	// (From, To, Cc, Bcc).
	GetParticipants() []string

	// GetEmbeddedMessageHints returns hints about embedded/quoted messages
	// that can be used for threading when headers are missing.
	GetEmbeddedMessageHints() []EmbeddedHint

	// SetThreadingInfo is called after reconstruction to provide
	// the computed threading information back to the message.
	SetThreadingInfo(info ThreadingInfo)
}

type ThreadingInfo struct {
	// ThreadID is a unique identifier for the thread this message belongs to.
	ThreadID string

	// ParentID is the MessageID of the parent message in the thread.
	// Empty if this is a root message.
	ParentID string

	// References is the reconstructed chain of message IDs leading to this message.
	References []string

	// Depth is the nesting depth in the thread (0 for root messages).
	Depth int
}