1+ import " EVM"
2+ import " FungibleToken"
3+ import " FlowEVMBridgeUtils"
4+ import " FlowEVMBridgeConfig"
5+ import " FungibleTokenMetadataViews"
6+
7+ /// Returns the balance of the owner of a given Fungible Token
8+ /// from their Cadence account and their COA
9+ /// Accepts multiple optional arguments, so the caller can query
10+ /// the token by its EVM ERC20 address or by its Cadence contract address and name
11+ ///
12+ /// @param owner: The Flow address of the owner
13+ /// @param contractAddressArg: The optional address of the FT contract in Cadence
14+ /// @param contractNameArg: The optional name of the FT contract in Cadence
15+ /// @param erc20AddressHex: The optional ERC20 address of the FT to query
16+ ///
17+ /// @return An array that contains the balance information for the user's accounts
18+ /// in this order:
19+ /// decimals (UInt256), cadence Balance (UFix64), EVM Balance (UInt256), Total Balance (UInt256)
20+ ///
21+
22+ access (all) fun main (
23+ owner Address ,
24+ vaultIdentifier String ?,
25+ erc20AddressHexArg String ?
26+ ): [AnyStruct ] {
27+ pre {
28+ vaultIdentifier == nil ? erc20AddressHexArg ! = nil : true :
29+ " If the Cadence contract information is not provided, the ERC20 contract address must be provided."
30+ }
31+
32+ var typeIdentifier : String = " "
33+ var compType : Type ? = nil
34+ var contractAddress : Address ? = nil
35+ var contractName : String ? = nil
36+ var tokenEVMAddress : String ? = nil
37+ var cadenceBalance : UFix64 = 0 .0
38+ var cadenceBalanceUInt256 : UInt256 = 0
39+ var coaBalance : UInt256 = 0
40+ var decimals : UInt8 = 0
41+
42+ // If the caller provided the Cadence information,
43+ // Construct the composite type
44+ if vaultIdentifier ! = nil {
45+ typeIdentifier = vaultIdentifier!
46+ compType = CompositeType (typeIdentifier)
47+ ?? panic (" Could not construct Cadence type with \(typeIdentifier)"
48+
49+ // Get the EVM address of the bridged version of the Cadence FT contract
50+ if let evmAddress = FlowEVMBridgeConfig.getEVMAddressAssociated (with : compType! ) {
51+ tokenEVMAddress = evmAddress.toString ()
52+ }
53+ } else {
54+ // If the caller provided the EVM information,
55+ // get the Cadence type from the bridge
56+ // If getting the Cadence type doesn't work, then we'll just return the EVM balance
57+ = erc20AddressHexArg!
58+ let address = EVM.addressFromString (tokenEVMAddress! )
59+ compType = FlowEVMBridgeConfig.getTypeAssociated (with : address)
60+ }
61+
62+ // Parse the FT identifier into its components if necessary
63+ if compType ! = nil {
64+ contractAddress = FlowEVMBridgeUtils.getContractAddress (fromType : compType! )
65+ contractName = FlowEVMBridgeUtils.getContractName (fromType : compType! )
66+ }
67+
68+ if let address = contractAddress {
69+ // Borrow a reference to the FT contract
70+ let resolverRef = getAccount (address)
71+ .contracts.borrow< &{FungibleToken}> (name: contractName! )
72+ ?? panic (" Could not borrow FungibleToken reference to the contract. Make sure the provided contract name ("
73+ .concat (contractName! ).concat (" ) and address (" concat (address.toString ()).concat (" ) are correct!"
74+
75+ // Use that reference to retrieve the FTView
76+ let vaultData = resolverRef.resolveContractView (resourceType : nil , viewType : Type< FungibleTokenMetadataViews.FTVaultData> ()) as! FungibleTokenMetadataViews.FTVaultData?
77+ ?? panic (" Could not resolve FTVaultData view. The " concat (contractName! )
78+ .concat (" contract needs to implement the FTVaultData Metadata view in order to execute this transaction."
79+
80+ // Get the Cadence balance of the token
81+ = getAccount (owner).capabilities.borrow< &{FungibleToken.Balance}> (
82+ vaultData.metadataPath
83+ )? .balance
84+ ?? 0 .0
85+ }
86+
87+ // Get the COA from the owner's account
88+ if let coa = getAuthAccount< auth (BorrowValue) &Account> (owner)
89+ .storage.borrow< auth (EVM.Call) &EVM.CadenceOwnedAccount> (
90+ from : / storage/ evm
91+ )
92+ {
93+ if let erc20Address = tokenEVMAddress {
94+ // Get the COA address
95+ let coaAddress = coa.address ().toString ()
96+
97+ // Get the ERC20 balance of the COA
98+ = FlowEVMBridgeUtils.balanceOf (
99+ owner : EVM.addressFromString (coaAddress),
100+ evmContractAddress : EVM.addressFromString (erc20Address)
101+ )
102+
103+ if cadenceBalance ! = 0 .0 {
104+ // Convert the Cadence balance to UInt256
105+ = FlowEVMBridgeUtils.convertCadenceAmountToERC20Amount (
106+ cadenceBalance,
107+ erc20Address : EVM.addressFromString (erc20Address)
108+ )
109+ }
110+
111+ // Get the token decimals of the ERC20 contract
112+ = FlowEVMBridgeUtils.getTokenDecimals (
113+ evmContractAddress : EVM.addressFromString (erc20Address)
114+ )
115+ }
116+ }
117+
118+ let balances = [decimals, cadenceBalance, coaBalance, cadenceBalanceUInt256+ coaBalance]
119+
120+ return balances
121+ }
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