Uniswap like SC

[ozsefw]

Implement a uniswap like LP in qubic

In the SC, users can create pools with two kind of asset, native qu and asset (like erc20)
users is able to add liqudity and remove liqudity from the pool,
the apis can be used in the contracts are following:

CreatePool

create a liqudity pool which can hold both native qu and asset

AddLiqudity, RemoveLiqudity

users can add/remove liqudity to/from the pool

SwapExactQuForAsset, SwapQuForExactAsset, SwapExactAssetForQu, SwapAssetForExactQu

users can swap in the pool by AMM with differnt requirement

SwapFee

query the protocol swap fee

GetPoolBasicState

get the pool state, such as totoal liqudity and reserve amount of native qu and asset

GetLiqudityOf (Not avaialbe currently)

QuoteExactQuInput, QuoteExactQuOutput, QuoteExactAssetInput, QuoteExactAssetOutput

get the amountIn/amountOut before swap

[Franziska-Mueller]

First of all, thank you for your contribution!
Please make sure to follow our guidelines for smart contract development: https://github.com/qubic/core/blob/main/doc/contracts.md
Currently, your PR does not conform with them (e.g. no changes to other files in src allowed)

[krypdkat]

Will add more comments later

[philippwerner]

Thanks for your contribution. I have some comments now and will continue reviewing later.

[krypdkat]

I have some comments about coding style and syntax, the rest look good to me. We can proceed proposal->ipo->going live after you addressing all comments.

Disclaimer: Ensuring correctness of the code and security of the funds in the contract is the responsibility of the team developing this contract. I (as a core dev) don’t have enough time for understanding all details and pentesting the SC. It's not the core devs responsibility to make sure this SC 100% bug-free but we do our best to give you the advices to avoid bugs based on our experience.
And my last advice is triple-checking everything before going live.

[philippwerner]

Some comments. The ones about compliance with licenses are very important IMO. I recommend to talk with @J0ET0M , because they may require some high-level decisions to be made.

[philippwerner]

Please don't rebase and force push, but merge the current develop of the official repo into your branch in the future.

[ozsefw]

Please don't rebase and force push, but merge the current develop of the official repo into your branch in the future.

Thanks for your feedback on the code review, I've just update the code, mainly the following items:

1. Add the information about the license for uin128, I'm wondering if my solution is ok
2. Remove the dependence in uint128.h
3. Merge current develop into this branch

[krypdkat]

@J0ET0M can you take a look at license thing for uint128

[philippwerner]

Thanks for addressing the comments. I have two minor requests additional. After addressing them, you can proceed with the proposal.

Please note the disclaimer written by dkat above. We recommend triple-checking everything before going live, because ensuring correctness of the code and security of the funds in the contract is the responsibility of the team developing this contract (NOT of the core devs reviewing and providing feedback).

[philippwerner]

Please note that the syntax of how contract procedures and functions are defined will change with the next release. See #361 for details.