How to decode transaction inputs from raw data using bitcoinjs-lib?

I need to calculate fees for each transaction in block.

I retrieve raw block data and use bitcoinjs-lib library to decode it to Block object:

const block = Bitcoin.Block.fromHex(data.rawblock);

It has an array of Transaction objects. However, while these transactions' outs have values, ins have only hash and script.

How should I process this data so I can get total in and out amounts and calculate transaction fee?

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Cryptocurrency expert here!