relational

type Baseline struct {
	// SQL is the output of pg_dump --schema-only of a database that has run
	// every migration up to and including Floor. Empty when the app has no baseline yet.
	SQL string
	// Floor is the highest name among the deleted migration files, as bun stores
	// it in the name column (the digits before the first underscore, not the
	// file name); SQL holds it and everything below it. Every migration named
	// at or below it must have its file deleted.
	Floor string
}

type DB struct {
	*bun.DB
	// MigrationDB is a second pool for migrations and the schema baseline load,
	// with no statement or read timeout and its own lock timeout. It is nil
	// when the driver does not provide one, then migrations run on DB.
	MigrationDB *bun.DB
}

type DBModel interface {
	// Validate checks the model for logical and business-rule correctness.
	Validate() error

	// Insert validates and inserts the model into the DB.
	Insert(ctx context.Context, db bun.IDB) error

	// Update validates and updates the model in the DB.
	Update(ctx context.Context, db bun.IDB) error

	// Delete removes the model from the DB.
	Delete(ctx context.Context, db bun.IDB) error
}

type Option func(db *DB) error

type PaginableModel interface {
	// GetCursor returns a stable, opaque value representing the record’s
	// position in the sorted result set.
	GetCursor() string

	// GetSortField returns the DB column used for ordering in pagination queries.
	GetSortField() string

	// GetSortValue returns the value of the sort field for this record.
	GetSortValue() interface{}

	// GetUniqueField returns the DB column that uniquely identifies this record.
	GetUniqueField() string

	// GetUniqueValue returns the value of the unique field for this record.
	GetUniqueValue() interface{}
}