// Package badgerstore is the Badger-backed implementation of
// libsignal.Store: one bridged chat's OMEMO identity, prekeys, and its
// remote peers' sessions/trust state.
//
// This is a dedicated database, separate from telegabber's existing
// id-mapping Badger DB (badger.IdsDB) - it holds private key material, so
// it gets its own lifecycle (optionally encrypted at rest) rather than
// sharing a file with the purely-operational id-mapping store.
package badgerstore

import (
	badger "github.com/dgraph-io/badger/v4"

	"dev.narayana.im/narayana/telegabber/e2ee/omemo/libsignal"
)

// DB is the OMEMO secrets database, shared across every bridged chat's
// identity (each gets its own key namespace within it - see Store).
type DB struct {
	db *badger.DB
}

// Open opens (creating if necessary) the OMEMO secrets database at path.
// If encryptionKey is non-empty, the database is encrypted at rest
// (badger.Options.WithEncryptionKey); its default BlockCacheSize (256MB)
// is left as-is, which badger requires to be non-zero whenever encryption
// is enabled.
func Open(path string, encryptionKey []byte) (*DB, error) {
	opts := badger.DefaultOptions(path)
	if len(encryptionKey) > 0 {
		opts = opts.WithEncryptionKey(encryptionKey)
	}
	bdb, err := badger.Open(opts)
	if err != nil {
		return nil, err
	}
	return &DB{db: bdb}, nil
}

// Store returns the libsignal.Store view of one bridged chat's OMEMO
// identity, scoped by (login, ownerPeerJID). ctx is used to split a stored
// combined identity key pair record into the separate public/private
// buffers libsignal.IdentityStore.GetIdentityKeyPair must return.
func (db *DB) Store(ctx *libsignal.Context, login, ownerPeerJID string) *Store {
	return &Store{db: db.db, ctx: ctx, login: login, owner: ownerPeerJID}
}

// Gc compacts the value log.
func (db *DB) Gc() {
	db.db.RunValueLogGC(0.7)
}

// Close closes the database.
func (db *DB) Close() error {
	return db.db.Close()
}