-CHAIN_ID="test"
-KEY_NAME="validator"
-KEYRING_BACKEND="test"
-FEES="500utia"
+CHAIN_ID="${CHAIN_ID:-test}"
+KEY_NAME="${KEY_NAME:-validator}"
+KEYRING_BACKEND="${KEYRING_BACKEND:-test}"
+FEES="${FEES:-500utia}"

 echo "Querying for pending upgrade..."
-celestia-appd query signal upgrade
+UPGRADE_STATUS=$(celestia-appd query signal upgrade -o json)
+if echo "$UPGRADE_STATUS" | jq -e '.upgrade.plan.height' > /dev/null; then
+    echo "Success: Upgrade to v3 is pending at height $(echo "$UPGRADE_STATUS" | jq -r '.upgrade.plan.height')"
+else
+    echo "Error: No pending upgrade found"
+    exit 1
+fi

+# Verify current block height
+CURRENT_HEIGHT=$(celestia-appd query block | jq -r '.block.header.height')
+if [ "$CURRENT_HEIGHT" -lt "3" ]; then
+    echo "Error: Current block height ($CURRENT_HEIGHT) is less than required height (3)"
+    exit 1
+fi

 echo "Submitting signal for v3..."
 celestia-appd tx signal signal 3 \
     --keyring-backend=${KEYRING_BACKEND} \
     --home ${CELESTIA_APP_HOME} \
     --from ${KEY_NAME} \
     --fees ${FEES} \
     --chain-id ${CHAIN_ID} \
     --broadcast-mode ${BROADCAST_MODE} \
     --yes
+
+# Verify signal submission success
+sleep 5  # Wait for transaction to be processed
+SIGNAL_COUNT=$(celestia-appd query signal tally 3 -o json | jq '.count')
+if [ "$SIGNAL_COUNT" -eq "0" ]; then
+    echo "Error: Signal submission failed"
+    exit 1
+fi

 deleteCelestiaAppHome() {
+    if [ -z "${APP_HOME}" ] || [ "${APP_HOME}" = "/" ]; then
+        echo "Error: Invalid APP_HOME path"
+        return 1
+    fi
+
+    if [ ! -d "${APP_HOME}" ]; then
+        echo "Nothing to delete: ${APP_HOME} does not exist"
+        return 0
+    fi
+
     echo "Deleting $APP_HOME..."
     rm -r "$APP_HOME"
 }

+modify_config() {
+    local file="$1"
+    local search="$2"
+    local replace="$3"
+    local backup="${file}.bak"
+    
+    if ! sed -i.bak "s#${search}#${replace}#g" "${file}"; then
+        echo "Error: Failed to modify ${file}"
+        return 1
+    fi
+    rm -f "${backup}"
+}

-sed -i'.bak' 's#"tcp://127.0.0.1:26657"#"tcp://0.0.0.0:26657"#g' "${APP_HOME}"/config/config.toml
+modify_config "${APP_HOME}/config/config.toml" \
+    '"tcp://127.0.0.1:26657"' \
+    '"tcp://0.0.0.0:26657"'

+cleanup() {
+    local pids=$(jobs -p)
+    if [ -n "${pids}" ]; then
+        kill ${pids} 2>/dev/null
+    fi
+}
+
+trap cleanup EXIT
+
 if [ -f $GENESIS_FILE ]; then
   echo "Do you want to delete existing ${APP_HOME} and start a new local testnet? [y/n]"
   read -r response
   if [ "$response" = "y" ]; then
     deleteCelestiaAppHome
     createGenesis
   fi
 else
   createGenesis
 fi

-upgradeToV3 & # Start the upgrade process from v2 -> v3 in the background.
-startCelestiaApp # Start celestia-app in the foreground.
+upgradeToV3 & 
+UPGRADE_PID=$!
+
+startCelestiaApp &
+APP_PID=$!
+
+wait $APP_PID || {
+    echo "Error: celestia-app process failed"
+    exit 1
+}

 upgradeToV3() {
-    sleep 45
+    local max_attempts=30
+    local attempt=1
+    local sleep_duration=10
+
+    echo "Waiting for chain to reach v2 upgrade height..."
+    while [ $attempt -le $max_attempts ]; do
+        if celestia-appd query block 2>/dev/null | grep -q '"version": "2"'; then
+            echo "Chain successfully upgraded to v2"
+            break
+        fi
+        echo "Attempt $attempt/$max_attempts: Chain not yet at v2..."
+        sleep $sleep_duration
+        attempt=$((attempt + 1))
+    done
+
+    if [ $attempt -gt $max_attempts ]; then
+        echo "Error: Timeout waiting for v2 upgrade"
+        return 1
+    fi

     echo "Submitting signal for v3..."
-    celestia-appd tx signal signal 3 \
+    if ! celestia-appd tx signal signal 3 \
         --keyring-backend=${KEYRING_BACKEND} \
         --home ${APP_HOME} \
         --from ${KEY_NAME} \
         --fees ${FEES} \
         --chain-id ${CHAIN_ID} \
         --broadcast-mode ${BROADCAST_MODE} \
-        --yes \
-        > /dev/null 2>&1
+        --yes > /dev/null 2>&1; then
+        echo "Error: Failed to submit v3 upgrade signal"
+        return 1
+    fi