package common

import (
	"errors"
)

// Error returned if a Producer has run to its end.
var ErrNoMoreBlocks = errors.New("No more blocks.")

type (
	// Block data from Minetest database.
	Block struct {
		Coord Coord
		Data  []byte
	}
	// BlockProducer is used to over a existing Minetest database
	// and return its content block by block.
	BlockProducer interface {
		// error is ErrNoMoreBlocks if it run out of blocks.
		Next(*Block) error
		// Closes the open database connections.
		Close() error
	}

	// BlockConsumer is used to store blocks in a new Minetest database.
	BlockConsumer interface {
		Consume(*Block) error
		// Closes the open database connections.
		Close() error
	}
)