package index

import (
	"fmt"
	"time"
)

// MailDocument is the indexed representation of a stored email.
type MailDocument struct {
	ID            string
	From          string
	To            string
	Subject       string
	Body          string
	AttachNames   string
	HasAttachment bool
	Date          time.Time
	Size          int64
	TenantID      *int64 // nil = global / superadmin context
}

// SearchRequest specifies search parameters.
type SearchRequest struct {
	Query         string
	From          string
	To            string
	OwnEmail      string
	DateFrom      *time.Time
	DateTo        *time.Time
	HasAttachment *bool  // nil=no filter, true=only with, false=only without
	LabelID       *int64 `json:"label_id,omitempty"` // PROJ-9: post-filter by label
	Sort          string // "relevance", "date_asc", "date_desc" (default: date_desc)
	PageSize      int
	Page          int
}

// Hit is a single search result.
type Hit struct {
	ID    string  `json:"id"`
	Score float64 `json:"score"`
}

// SearchResult holds paginated search results.
type SearchResult struct {
	Total int
	Hits  []Hit
}

// Indexer is the interface for full-text email indexing.
type Indexer interface {
	IndexSync(doc MailDocument) error
	Search(req SearchRequest) (*SearchResult, error)
	Delete(id string) error
	Close() error
}

// TenantIndexer manages per-tenant Indexer instances.
// Implemented by ManticoreTenantManager (primary) and TenantIndexManager (legacy Xapian).
type TenantIndexer interface {
	ForTenant(tenantID *int64) Indexer
	Global() Indexer
	Close() error
}

// New creates an Indexer for the specified backend.
// Deprecated: use NewManticoreTenantManager instead.
func New(dir string, batchSize int, backend string) (Indexer, error) {
	switch backend {
	case "xapian":
		return newXapian(dir)
	default:
		return nil, fmt.Errorf("unknown index backend: %q (use manticore via NewManticoreTenantManager)", backend)
	}
}