vtab

type Constraint struct {
	Column int
	Op     ConstraintOp
	Usable bool
	// ArgIndex selects which position in argv[] (0-based) should contain the
	// RHS value for this constraint when Filter is called. Set to -1 to ignore.
	ArgIndex int
	// Omit requests SQLite to omit the corresponding constraint from the
	// parent query if the virtual table fully handles it.
	Omit bool
}

type ConstraintOp int

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

type Cursor interface {
	// Filter corresponds to xFilter. idxNum and idxStr are the chosen index
	// number and string; vals are the constraint arguments.
	Filter(idxNum int, idxStr string, vals []Value) error

	// Next advances the cursor to the next row (xNext).
	Next() error

	// Eof reports whether the cursor is past the last row (xEof != 0).
	Eof() bool

	// Column returns the value of the specified column in the current row
	// (xColumn).
	Column(col int) (Value, error)

	// Rowid returns the current rowid (xRowid).
	Rowid() (int64, error)

	// Close closes the cursor (xClose).
	Close() error
}

type IndexInfo struct {
	Constraints []Constraint
	OrderBy     []OrderBy

	// IdxNum selects the query plan chosen in BestIndex. This value is passed
	// back to Cursor.Filter. Note: SQLite stores this as a 32-bit signed
	// integer (int32). Implementations must ensure IdxNum fits within the
	// int32 range; values outside of int32 will cause an error in the driver
	// to avoid silent truncation.
	IdxNum int64
	IdxStr string
	// IdxFlags provides extra information about the chosen plan.
	// Set to IndexScanUnique to indicate the plan visits at most one row.
	IdxFlags        int
	OrderByConsumed bool
	EstimatedCost   float64
	EstimatedRows   int64
	// ColUsed is a bitmask indicating which columns are used by the query.
	// Bit N is set if column N is referenced.
	ColUsed uint64
}

type Module interface {
	// Create is called to create a new virtual table. args corresponds to the
	// argv array passed to xCreate in the SQLite C API: it contains the module
	// name, the database name, the table name, and module arguments.
	Create(ctx Context, args []string) (Table, error)

	// Connect is called to connect to an existing virtual table. Its
	// semantics mirror xConnect in the SQLite C API.
	Connect(ctx Context, args []string) (Table, error)
}

type OrderBy struct {
	Column int
	Desc   bool
}

type Renamer interface {
	Rename(newName string) error
}

type Table interface {
	// BestIndex allows the virtual table to inform SQLite about which
	// constraints and orderings it can efficiently support. The IndexInfo
	// structure mirrors sqlite3_index_info.
	BestIndex(info *IndexInfo) error

	// Open creates a new cursor for scanning the table.
	Open() (Cursor, error)

	// Disconnect is called to disconnect from a table instance (xDisconnect).
	Disconnect() error

	// Destroy is called when a table is dropped (xDestroy).
	Destroy() error
}

type Transactional interface {
	Begin() error
	Sync() error
	Commit() error
	Rollback() error
	Savepoint(i int) error
	Release(i int) error
	RollbackTo(i int) error
}

type Updater interface {
	Insert(cols []Value, rowid *int64) error
	Update(oldRowid int64, cols []Value, newRowid *int64) error
	Delete(oldRowid int64) error
}

type Value = driver.Value