TransactionPanel has no Stellar address format validation or balance check before submission

[k-deejah]

Problem

src/components/TransactionPanel.tsx canSubmit guard (line 24) only checks that dest is a non-empty string and amount is a positive number:

const canSubmit = isConnected && dest.trim() && amount.trim() && parseFloat(amount) > 0;

There is no Stellar address format validation. A Stellar public key must start with G, be exactly 56 characters, and pass a base32 checksum. Users can currently enter abc, 0x1234, or an Ethereum address and the form will submit it to the network, wasting fees and confusing users with an opaque network error.

Two more related problems: (1) there is no balance check — entering an amount that exceeds the user's XLM balance submits to the network and fails there, rather than showing a clear inline error before submission; (2) the amount field uses type="number" but has no max attribute, so there is no browser-level upper bound either.

Solution

1. Add a Stellar address validator. Use the regex /^G[A-Z2-7]{55}$/ for a lightweight check, or import StrKey.isValidEd25519PublicKey from @stellar/stellar-sdk for full checksum validation.
2. Show an inline error under the Destination Address Input when format is invalid.
3. Compare parseFloat(amount) against the XLM balance from useSorokit() context and show an "Insufficient balance" error when exceeded.
4. Keep canSubmit false while either validation fails.

Acceptance Criteria

• Entering a non-G string in Destination shows an inline validation error
• Entering a string shorter or longer than 56 characters shows an inline error
• The Send button is disabled until the destination passes validation
• Entering an amount above the XLM balance shows an "Insufficient balance" error
• Valid addresses and amounts do not trigger false errors
• Network submission is only attempted when all client-side checks pass

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[OLAMIGHTY010]

@OLAMIGHTY010 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I would like to work on this project

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[chiemezie1]

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[kaizercodes]

@kaizercodes has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi, I can fix this
kindly assign

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[DevSolex]

@DevSolex has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi Maintainer,

I’m a smart contract and full-stack developer and would love to contribute to this issue. I’m an experienced contributor with hands-on expertise in Rust, Soroban, Cairo, and TypeScript.

I’m passionate about building secure, scalable blockchain solutions, with a strong emphasis on writing clean and maintainable code. Based on the scope of this issue, I’m confident I can deliver a complete solution within 24 hours of assignment.

I’d greatly appreciate the opportunity to contribute and help move this forward.

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[Benedict315]

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Hello please assign me

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[Muyideen-js]

@Muyideen-js has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi, I can fix this

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[dollfins]

@dollfins has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello maintainer, i would love to fix this issue kindly assign it to me Thanks

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[anifast-123]

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Hello maintainer, i would like to work on this issue

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[payfoxX]

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I love to fix this issue, kindly assign it to me. Thanks

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[VeronicDev]

@VeronicDev has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi, I can fix this pls assign

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