- the spec says response to getBlockHashes(from, max) should return all hashes starting from PARENT of from. This required major changes and results in much hackier code.
- Introduced a first round block request after peer introduces with current head, so that hashes can be linked to the head
- peerInfo records currentBlockHash, currentBlock, parentHash and headSection
- AddBlockHashes checks header section and creates the top node from the peerInfo of the best peer
- AddBlock checks peerInfo and updates the block there rather than in a node
- request further hashes once a section is created but then no more until the root block is found (so that we know when to stop asking)
- in processSection, when root node is checked and receives a block, we need to check if the section has a parent known to blockchain or blockPool
- when peers are switched, new peer launches a new requestHeadSection loop or activates its actual head section, i.e., the section for it currentBlockHash
- all tests pass
