web authn private key to keystore format

web_authn_pem_to_keystore.sh

#!usr/bin/env bash
# !ACHTUNG: Use at your own risk, AI slop generated
# You can export web authn private key using devtools web authn thingy
# Play stupid games, win retarded prizes
# Avoid contact with eyes, apply directly to forehead
# 

PEM_FILE="private_key.pem"
KEYSTORE_NAME="my_eth_wallet"

echo "Extracting private key from PEM file..."

if openssl ec -in "$PEM_FILE" -noout 2>/dev/null; then
    # Extract private key as hex
    PRIVATE_KEY=$(openssl ec -in "$PEM_FILE" -noout -text 2>/dev/null | \
                  sed -n '/priv:/,/pub:/p' | \
                  grep -v pub: | \
                  tr -d ' \n:' | \
                  sed 's/priv://')
    
    # Ensure it starts with 0x
    if [[ ! $PRIVATE_KEY == 0x* ]]; then
        PRIVATE_KEY="0x$PRIVATE_KEY"
    fi
    
    # There should probably be a bytes size check too but hey chatgpt free plan you know
    
    # Man this is sketchy
    echo "Private key extracted: ${PRIVATE_KEY:0:10}..."
    # 
    
    # Import into cast keystore
    echo "Importing into cast keystore..."
    cast wallet import "$KEYSTORE_NAME" --private-key "$PRIVATE_KEY"
    
    echo "Wallet imported successfully! Use with:"
    echo "cast send --account $KEYSTORE_NAME --rpc-url \$RPC_URL ..."
    
else
    echo "Error: PEM file doesn't contain an EC private key suitable for Ethereum"
    exit 1
fi