wallet-prefill-provider.ts

import type { InstructionData } from '@entities/idl';
import { PublicKey } from '@solana/web3.js';
import type { MutableRefObject } from 'react';
import type { FieldPath, UseFormReturn } from 'react-hook-form';

import type { FormValue, InstructionFormData, InstructionFormFieldNames } from '../../use-instruction-form';
import { isPrefilledAccount, WALLET_ACCOUNT_PATTERNS } from '../const';
import { traverseInstructionAccounts } from './traverse-accounts';

/**
 * Creates a wallet prefill dependency that automatically fills signer accounts
 * with the wallet's public key when the wallet connects or changes.
 */
export function createWalletPrefillDependency(
    instruction: InstructionData,
    fieldNames: Pick<InstructionFormFieldNames, 'account'>,
    lastPrefillAddressRef: MutableRefObject<string | undefined>,
): { onValueChange: (value: unknown, form: UseFormReturn<InstructionFormData>) => void } {
    const signerPaths: FieldPath<InstructionFormData>[] = [];

    traverseInstructionAccounts(instruction, (account, parentGroup) => {
        // Skip accounts that have known addresses (e.g., system program, token program)
        if (isPrefilledAccount(account.name)) {
            return;
        }

        const normalizedName = account.name.toLowerCase().trim();
        const isWalletAccount = WALLET_ACCOUNT_PATTERNS.some(p => normalizedName === p.toLowerCase());

        // Prefill wallet address for:
        // - signer accounts (user needs to sign)
        // - accounts matching wallet patterns (e.g., authority)
        // - writable accounts that are not PDAs (likely owned/controlled by the user)
        const shouldPrefill = account.signer || isWalletAccount || (account.writable && !account.pda);

        if (shouldPrefill) {
            if (parentGroup) {
                signerPaths.push(fieldNames.account(parentGroup, account));
            } else {
                signerPaths.push(fieldNames.account(account));
            }
        }
    });

    return {
        onValueChange: (value: unknown, form: UseFormReturn<InstructionFormData>) => {
            if (!value || !(value instanceof PublicKey)) return;

            const walletAddress = value.toBase58();
            const lastPrefillAddress = lastPrefillAddressRef.current;

            for (const path of signerPaths) {
                const currentValue = String(form.getValues(path) ?? '').trim();
                const isEmpty = currentValue === '';
                const hasPreviousWallet = lastPrefillAddress !== undefined && currentValue === lastPrefillAddress;

                if (isEmpty || hasPreviousWallet) {
                    form.setValue(path, walletAddress as unknown as FormValue, {
                        shouldDirty: false,
                        shouldValidate: false,
                    });
                }
            }

            lastPrefillAddressRef.current = walletAddress;
        },
    };
}