#!/bin/bash

set -e

echo "=========================================="
echo "  iSCSI Target Configuration Script"
echo "=========================================="
echo ""

if [ "$EUID" -ne 0 ]; then
    echo "Error: This script must be run as root"
    exit 1
fi

TGT_CONFIG_DIR="/etc/tgt/conf.d"
ISCSI_IQN_BASE="iqn.2024-01.com.vtl-linux"

echo "[1/4] Installing iSCSI target software..."
apt-get update
apt-get install -y tgt

echo "[2/4] Configuring iSCSI targets..."
mkdir -p "$TGT_CONFIG_DIR"

cat > "$TGT_CONFIG_DIR/vtl-targets.conf" << 'EOF'
<target iqn.2024-01.com.vtl-linux:vtl.lun0>
    backing-store /dev/sg1
    initiator-address ALL
    incominguser vtl-user vtl-password
    write-cache on
</target>

<target iqn.2024-01.com.vtl-linux:vtl.lun1>
    backing-store /dev/sg2
    initiator-address ALL
    incominguser vtl-user vtl-password
    write-cache on
</target>

<target iqn.2024-01.com.vtl-linux:vtl.lun2>
    backing-store /dev/sg3
    initiator-address ALL
    incominguser vtl-user vtl-password
    write-cache on
</target>

<target iqn.2024-01.com.vtl-linux:vtl.lun3>
    backing-store /dev/sg4
    initiator-address ALL
    incominguser vtl-user vtl-password
    write-cache on
</target>

<target iqn.2024-01.com.vtl-linux:vtl.changer>
    backing-store /dev/sg0
    initiator-address ALL
    incominguser vtl-user vtl-password
    device-type changer
</target>
EOF

echo "[3/4] Configuring firewall..."
if command -v ufw &> /dev/null; then
    ufw allow 3260/tcp
    ufw reload
elif command -v firewall-cmd &> /dev/null; then
    firewall-cmd --permanent --add-port=3260/tcp
    firewall-cmd --reload
else
    iptables -A INPUT -p tcp --dport 3260 -j ACCEPT
    iptables-save > /etc/iptables/rules.v4
fi

echo "[4/4] Starting iSCSI target service..."
systemctl enable tgt
systemctl restart tgt

sleep 2

echo ""
echo "=========================================="
echo "  iSCSI Target Configuration Complete!"
echo "=========================================="
echo ""
echo "Available targets:"
tgt-admin --show
echo ""
echo "Connection information:"
echo "  - Port: 3260"
echo "  - IQN Base: $ISCSI_IQN_BASE"
echo "  - Username: vtl-user"
echo "  - Password: vtl-password"
echo ""
echo "Client connection examples:"
echo ""
echo "Linux:"
echo "  iscsiadm -m discovery -t st -p <SERVER_IP>:3260"
echo "  iscsiadm -m node --login"
echo ""
echo "Windows:"
echo "  iscsicli QAddTargetPortal <SERVER_IP>"
echo "  iscsicli ListTargets"
echo "  iscsicli LoginTarget <target_name> T * * * * * * * * * * * * * * * <username> <password>"
echo ""