package store

import "axolotl/models"

// GraphStore is a primitive graph persistence interface. It provides basic
// operations for nodes and directed rels. No business logic lives here.
// "Tag" rels are rels with an empty toID (e.g. "_type::issue" or "backend").
type GraphStore interface {
	// Nodes
	AddNode(id, title, content, dueDate, createdAt, updatedAt string) error
	GetNode(id string) (*models.Node, error) // returns node with tags and rels populated
	UpdateNode(id, title, content, dueDate, updatedAt string) error // empty dueDate stores NULL
	DeleteNode(id string) error
	NodeExists(id string) (bool, error)
	GenerateID() (string, error) // returns a random 5-char ID guaranteed unique in the store

	// Rels: relName is the relation name; toID is empty for "tag" rels (properties/labels).
	AddRel(nodeID, relName, toID string) error
	RemoveRel(nodeID, relName, toID string) error

	// FindNodes returns fully-populated nodes matching all given filters.
	// Filters with empty Target match nodes by rel_name prefix with empty toID (tag/property).
	// Filters with non-empty Target match nodes by exact rel_name and toID (edge).
	FindNodes(filters []*models.Rel) ([]*models.Node, error)

	// Transaction runs fn inside an atomic transaction. If fn returns an error
	// the transaction is rolled back; otherwise it is committed.
	// Calls to Transaction inside fn reuse the same transaction (no nesting).
	Transaction(fn func(GraphStore) error) error
}